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2024 (136)

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This study evaluated 22 spring-type faba bean cultivars in the main areas for cultivation of faba bean in Norway to assess the variation of 14 faba bean traits due to cultivar (G), environment (E), and their interaction (G × E), and to assess their stability across environments by using the additive main effects and multiplicative interaction (AMMI) analysis and coefficient of variation (CV). Significant G, E, and G × E effects were found for most traits, with environment accounting for much of the variance in yield and the growing degree days (GDD) to different developmental stages. Yield was highly correlated with thousand kernel weight (TKW) and GDD to BBCH 89 (maturation). The stability of the cultivars was studied for yield, TKW, and GDD to BBCH 89. Stability analysis using the AMMI stability value, yield stability index, CV, and the average sum of ranks identified Birgit, Stella, Bobas, and Macho as the most stable high-yielding cultivars across environments, achieving a mean yield of 6–6.4 tons ha−1. Bobas, Macho, Stella, and Yukon had the most stable TKW (612–699 g) and Bobas, Capri, Trumpet, and Vertigo were the most stable regarding GDD to BBCH 89 (1257°C days, with a base temperature of 5°C). These stable cultivars can be utilized in breeding programs to achieve high and stable faba bean yield in the main growing areas of Norway and other Nordic-Baltic countries.

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Despite the high density of brown bears (Ursus arctos piscator) on the Kamchatka peninsula their genetic variation has not been studied by STR analysis. Our aim was, therefore, to provide population data from the Kamchatka brown bear population applying a validated DNA profiling system. Twelve dinucleotide STRs commonly used in Western-European (WE) populations and four additional ones (G10C, G10J, G10O, G10X), were included. Template input ≥ 0.2 ng was successfully amplified. Measurements of precision, stutter and heterozygous balance showed that markers could be reliably genotyped applying the thresholds used for genotyping WE brown bears. However, locus G10X revealed an ancient allele-specific polymorphism that led to suboptimal amplification of all 174 bp alleles (Kamchatka and WE). Allele frequency estimates and forensic genetic parameters were obtained from 115 individuals successfully identified by genotyping 434 hair samples. All markers met the Hardy-Weinberg and linkage equilibrium expectations, and the power of discrimination ranged from 0.667 to 0.962. The total average probability of identity from the 15 STRs was 1.4 ×10−14 (FST = 0.05) while the total average probability of sibling identity was 6.0 ×10−6. Relationship tests revealed several parent-cub and full sibling pairs demonstrating that the marker set would be valuable for the study of family structures. The population data is the first of its kind from the Kamchatka brown bear population. Population pairwise FST`s revealed moderate genetic differentiation that mirrored the geographic distances to WE populations. The DNA profiling system, providing individual-specific profiles from non-invasive samples, will be useful for future monitoring and conservation purposes

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Conservation biological control (CBC) is a sustainable measure for ecological intensification in agriculture to establish and maintain robust natural enemy populations. CBC is contributing to integrated pest management with reduced use of pesticides and support of native biodiversity in agroecosystems. Despite rapidly expanding research on CBC during the last decades, its application in pest management at the farm level is very limited. Here, we tested a CBC strategy in a 5-year on-farm study at three locations in East Norway. This CBC strategy combined two tools to increase biological control of aphids in spring barley; 1-ATTRACT, the application of a volatile organic compound (VOC) attractant that increases lacewing egg laying, and 2-HABITAT, the maintenance of natural border vegetation. We found that the VOC attractants recruited natural enemies and guided them to the right place at the right time from the border vegetation into the cropping area to control the aphid population efficiently and reliably. The results also showed that the VOC attractants combined with periodical maintained natural border vegetation provided a higher lacewing activity and aphid suppression than with annual sown floral buffer strips. We found that maintained natural border vegetation supported by VOC attractants provided lacewing populations that controlled aphids up to 100 m into the cropping area. Without VOC attractants we recorded lacewing activity up to 50 m from the border into the cropping area if natural border vegetation was available, and up to 25 m if no border vegetation existed. The overall results demonstrated the feasibility of this CBC approach under Norwegian farming conditions leading to the successful adoption of this CBC-strategy by the farming community.

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Invasive pests and plant pathogens pose a significant threat to ecosystems and economies worldwide, prompting the need of anticipatory strategies. Preventing their introduction by detection at the ports of entry has been proven extremely difficult. This review explores the potential of biogenic volatile detection as a reliable preventive solution. It underscores the importance of early detection and rapid response as integral components of effective invasive pest management, and it discusses the limitations of current control measures and the increasing globalization that facilitates the spread of pests and pathogens. Through a synthesis of existing literature, this review analyzes the Volatile Organic Compound (VOC) emissions in five invasive model species: three insects, Halyomorpha halys, Spodoptera frugiperda, Helicoverpa armigera, a nematode, Bursaphelenchus xylophilus, and an oomycete, Phytophthora ramorum. The review focuses on the specific volatiles, released by both the invasive organisms and the infested host plants. If available, the volatiles emitted from similar species were considered for comparison. Ultimately, this review highlights specific pest volatile and shared Herbivore Induced Plant Volatiles (HIPVs) as a reliable and innovative solution in pest detection. If possible, candidate compounds are provided, whilst the lack of some emphasizes the urge of expanding the information available.

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Entomophagy, the consumption of insects, may reduce the negative health and environmental impacts of meat. As one of the novel protein alternatives expected to replace conventional meat consumption, its success will depend on consumer acceptance. To investigate the consumer acceptance of entomophagy, three rounds of a Norwegian survey with 8633 useable responses conducted in 2019/2020, 2021/2022, and 2023/2024 were used. Generalized structural equation modelling was used to test the developed hypotheses. The direct effects of trust, food choice motives, and OCEAN personality traits were investigated. The mediating effects of food safety concerns on the relationship between trust and willingness to try (WTT) food made from insects were also investigated. Social trust and trust in food authorities were positively associated with WTT. No association was found for trust in retailers. Negative associations were found between the effects of social trust and trust in food authorities on food safety concerns, and food safety concern was also a significant mediator. Respondents who emphasized environmental friendliness, health, and novelty were more willing to try, and those who emphasized natural ingredients and familiarity were less willing. Openness was positively associated with WTT, while conscientiousness, extraversion, and agreeableness had a negative association. Gender, education, age and urban living were also found as significant moderators in some paths. The findings of the study imply the need to foster trust among consumers and to emphasize the environmental and health benefits of entomophagy while focusing on increasing consumer familiarity and use of natural ingredients. Personality-focused marketing strategies may also be implored to target consumers high in openness and low in conscientiousness, extraversion, and agreeableness.

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A sustainable dietary transition requires knowledge of the drivers and barriers of dietary choices. We investigate the role of preferences for domestic food, as well as environmental and health concerns, as drivers for the consumption of red and white meat, fish, ready-made plant-based food products and self-identification as some type of meat reducer (flexitarian, vegetarian, or vegan). A survey of 1102 consumers was conducted in Norway with questions about food attitudes, beliefs and preferences regarding health, the environment and domestic food as well as dietary habits and demographics. The results from interval and logistic regression analyses show that stronger preferences for domestic food are associated with higher consumption of red meat and a lower likelihood of eating plant-based food and identifying as a meat reducer. Health concerns are associated with higher consumption of white meat and fish, and environmental concern is associated with lower consumption of white meat and a higher likelihood of eating plant-based food. The results also confirm previous research results that disbelief regarding the negative health and environmental impacts of meat correlate with higher meat consumption and a lower likelihood of eating plant-based food. In addition, we find that people who believe that Norway is a country primarily suited for livestock production have higher consumption of meat and a lower likelihood of eating plant-based food. We conclude that to make certain consumers transition away from meat, it is important to provide domestically produced, plant-based alternatives and to implement policy measures that will generate positive storylines of improved farmer livelihoods.

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Cultured meat (CM) is likely to reduce environmental footprints and health problems and improve animal welfare, but its success in the market will rely on consumer acceptance. A survey was used to investigate consumer acceptance of CM in Norway. The survey was conducted pre the COVID-19 pandemic and during the pandemic with a total of 4,683 usable responses. A partial proportional odds model was estimated, and identical coefficients were not rejected for the two periods. Social trust, trust in food authorities, and support to green parties were positively associated with the willingness to try CM but there was no association with trust in food retailers. Respondents who emphasized natural components and food safety were less willing, and respondents who emphasized health, novelty, environment, and price were more willing. Young, male, highly educated, urban, non-religious, non-vegetarian supporters of green parties were also more willing to try CM, and marketing activities should target these groups.

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Tree species composition is essential information for forest management and remotely sensed (RS) data have proven to be useful for its prediction. In forest management inventories, tree species are commonly interpreted manually from aerial images for each stand, which is time and resource consuming and entails substantial uncertainty. The objective of this study was to evaluate a range of RS data sources comprising airborne laser scanning (ALS) and airborne and satellite-borne multispectral data for model-based prediction of tree species composition. Total volume was predicted using non-linear regression and volume proportions of species were predicted using parametric Dirichlet models. Predicted dominant species was defined as the species with the greatest predicted volume proportion and predicted species-specific volumes were calculated as the product of predicted total volume multiplied by predicted volume proportions. Ground reference data obtained from 1184 sample plots of 250 m2 in eight districts in Norway were used. Combinations of ALS and two multispectral data sources, i.e. aerial images and Sentinel-2 satellite images from different seasons, were compared. The most accurate predictions of tree species composition were obtained by combining ALS and multi-season Sentinel-2 imagery, specifically from summer and fall. Independent validation of predicted species proportions yielded average root mean square differences (RMSD) of 0.15, 0.15 and 0.07 (relative RMSD of 30%, 68% and 128%) and squared Pearson's correlation coefficient (r2) of 0.74, 0.79 and 0.51 for Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and deciduous species, respectively. The dominant species was predicted with median values of overall accuracy, quantity disagreement and allocation disagreement of 0.90, 0.07 and 0.00, respectively. Predicted species-specific volumes yielded average values of RMSD of 63, 48 and 23 m3/ha (relative RMSD of 39%, 94% and 158%) and r2 of 0.84, 0.60 and 0.53 for spruce, pine and deciduous species, respectively. In one of the districts with independent validation plots of mean size 3700 m2, predictions of the dominant species were compared to results obtained through manual photo-interpretation. The model predictions gave greater accuracy than manual photo-interpretation. This study highlights the utility of RS data for prediction of tree species composition in operational forest inventories, particularly indicating the utility of ALS and multi-season Sentinel-2 imagery.

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It is widely acknowledged that welfare states are important determinants of health in Europe through their mediation of the extent, and impact, of socio-economic positions on health. Arguably, immunisation from market dependencies in healthcare has been associated with core public values of the traditional welfare state and has thus been perceived important for achieving public goods such as social cohesion, equity, and people’s well-being. In recent years, we have seen a change in change in welfare states, where policies aimed at decommodifying the citizens by sheltering them from market dependency, have been supplemented and even replaced by the reverse trend of healthcare recommodification, where the role of markets has been strengthened and access to services through citizenship has been reduced. There is consequently a need for studies that investigate the specific welfare regime features that best contribute to the protection and promotion of the well-being of its citizens. Concentrating on the healthcare part of the welfare state, we analyse differences of subjective perceptions of well-being (self-rated health and happiness) between European countries, by examining how such perceptions are associated with selected indicators related to expenditure, financing, provision, institutional features, primary care orientation, and health decommodification. The paper utilises ten rounds of the European Social Survey (ESS), spanning 20 years and including more than 130,000 individuals from 21 countries. Using multilevel modelling and controlling for individual-level demographic and socio-economic variables, the results suggest that several of the system characteristics are relevant for subjective perceptions of well-being. Public healthcare coverage shows the strongest positive association, while indicators of public–private mix in financing and private provision of healthcare showed less significant results.

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Background Neck pain remains a persistent challenge in modern society and is frequently encountered across a wide range of occupations, particularly those involving repetitive and monotonous tasks. It might be expected that patterns of trapezius muscle activity at work, characterized by few breaks and prolonged periods of sustained muscle activity, are linked to neck pain. However, previous cross-sectional studies have generally failed to establish a definitive association. While some longitudinal studies have suggested that extended periods of heightened muscle activity could be a risk factor for neck pain, these findings often relied on limited participant numbers or specific professional groups. This study aimed to investigate the relationship between trapezius muscle activity and neck pain by pooling data from seven Scandinavian research institutes encompassing a diverse range of occupational backgrounds. Methods Electromyographic (EMG) data for the upper trapezius muscle, collected during working hours, were coupled with questionnaire responses pertaining to neck pain, individual characteristics, and potential confounding variables for a total of 731 subjects. Additionally, longitudinal data from 258 subjects were available. The various EMG datasets were consolidated into a standardized format, and efforts were made to harmonize inquiries about neck pain. Regression analyses, adjusting for sex and height, were conducted to explore the associations between muscle activity variables and neck pain. An exposure index was devised to quantify the cumulative neck load experienced during working hours and to differentiate between various occupational categories. Results The cross-sectional data displayed a distinct pattern characterized by positive associations for brief periods of sustained muscle activity (SUMA) and negative associations for prolonged SUMA-periods and neck pain. The longitudinal data exhibited a contrasting trend, although it was not as pronounced as the cross-sectional findings. When employing the exposure index, notable differences in cumulative muscle load emerged among occupational groups, and positive associations with longitudinal neck pain were identified. Discussion The results suggest that individuals with neck pain experience higher cumulative workloads and extended periods of muscle activity over the long term. In the short term, they appear to compensate by taking frequent short breaks, resulting in a lower cumulative workload. Regardless of their occupation, it is crucial to distribute work breaks throughout the workday to ensure that the cumulative load remains manageable.

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Ongoing Arctic greening can increase productivity and reindeer pasture quality in the tundra. However, greening may also entail proliferation of unpalatable species, with consequences for pastoral social-ecological systems. Here we show extensive greening across 20 reindeer districts in Norway between 2003 and 2020, which has reduced pasture diversity. The allelopathic, evergreen dwarf-shrub crowberry increased its biomass by 60%, with smaller increases of deciduous shrubs and no increase in forbs and graminoids, the most species rich growth forms. There was no evidence for higher reindeer densities promoting crowberry. The current management decision-making process aims at sustainable pasture management but does not explicitly account for pasture changes and reduced diversity. Large-scale shifts towards evergreening and increased allelopathy may thus undermine the resource base for this key Arctic herbivore and the pastoral social-ecological system. Management that is sensitive to changes in pasture diversity could avoid mismanagement of a social-ecological system in transition.

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Global environmental change may lead to changes in community structure and in species interactions, ultimately changing ecosystem functioning. Focusing on spatial variation in fungus–plant interactions across the rapidly changing Arctic, we quantified variation in the identity of interaction partners. We then related interaction turnover to variation in the bioclimatic environment by combining network analyses with general dissimilarity modelling. Overall, we found species associations to be highly plastic, with major rewiring among interaction partners across variable environmental conditions. Of this turnover, a major part was attributed to specific environmental properties which are likely to change with progressing climate change. Our findings suggest that the current structure of plant-root associated interactions may be severely altered by rapidly advancing global warming. Nonetheless, flexibility in partner choice may contribute to the resilience of the system.

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Aquaculture constitutes an important source of protein, essential omega-3 fatty acids and bioavailable micronutrients for humans. The increasing demand for aquatic food products has resulted in more intensive farming practices leading to negative impacts on aquaculture organisms and marine ecosystems. Disease outbreaks cause more than 6 billion USD loss worldwide annually and possess high risks of spreading to the wild fauna especially by viral infections. Vaccination has been proved to be effective to mitigate these problems and widely used as prophylaxis in aquaculture, but available vaccines against viral nervous necrosis (VNN) are limited currently. Plant platforms have several advantages and have been proposed as an alternative biomanufacturing method for vaccine antigens. In the present study, we report: (1) selection and design of recombinant plasmids encoding the capsid proteins (CPs) of two genotypes of NNV, red-spotted grouper nervous necrosis virus (RGNNV) and striped jack nervous necrosis virus (SJNNV); (2) design and optimization of plasmids for transient expression of NNV vaccine antigens in wild type Nicotiana benthamiana, CRISPR/Cas9 genome edited Nicotiana benthamiana and Lactuca sativa; (3) test of different Agrobacterium strains (LBA4404 and AGL1) for effective production of NNVCPs; (4) the expression patterns of NNVCPs over time post infiltration for different plants and cultivars; (5) successful production of NNV antigens in N. benthamiana lines and lettuce cultivars, indicating the potential of the plants as antigen producers in the development of a plant-based vaccine against VNN.

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In many species, polymorphic genomic inversions underlie complex phenotypic polymorphisms and facilitate local adaptation in the face of gene flow. Multiple polymorphic inversions can co-occur in a genome, but the prevalence, evolutionary significance, and limits to complexity of genomic inversion landscapes remain poorly understood. Here, we examine genome-wide genetic variation in one of Europe's most destructive forest pests, the spruce bark beetle Ips typographus, scan for polymorphic inversions, and test whether inversions are associated with key traits in this species. We analyzed 240 individuals from 18 populations across the species' European range and, using a whole-genome resequencing approach, identified 27 polymorphic inversions covering ∼28% of the genome. The inversions vary in size and in levels of intra-inversion recombination, are highly polymorphic across the species range, and often overlap, forming a complex genomic architecture. We found no support for mechanisms such as directional selection, overdominance, and associative overdominance that are often invoked to explain the presence of large inversion polymorphisms in the genome. This suggests that inversions are either neutral or maintained by the combined action of multiple evolutionary forces. We also found that inversions are enriched in odorant receptor genes encoding elements of recognition pathways for host plants, mates, and symbiotic fungi. Our results indicate that the genome of this major forest pest of growing social, political, and economic importance harbors one of the most complex inversion landscapes described to date and raise questions about the limits of intraspecific genomic architecture complexity.

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This study investigated the effects of substrates composed of various ratios of wood fiber and peat (0, 25, 50, 75, and 100% peat (v/v)) mixed with different amounts of lime (0, 2, 4, 6, and 8 g L−1) and start fertilizer (0, 2, and 4 g L−1 Multimix) on the growth and biomass accumulation of petunia (Petunia x hybrida Vilm ‘Finity F1 Purple’) and basil (Ocimum basilicum L. ‘Marian’) in an ebb-and-flow greenhouse system. Growth parameters included plant height, weight, canopy diameter, and chlorosis symptoms for petunia, along with substrate pH and EC measurements. Petunia showed optimal growth in substrates with higher peat content, while basil produced satisfactory biomass across a pH range of 5–7 regardless of substrate type. Optimal petunia cultivation in 100% wood fiber required a significant dose of start fertilizer without lime. Monitoring pH and EC using pour-through and press methods revealed a pH decrease in substrates with added start fertilizer, while substrates with higher wood fiber content were less acidic. Substrates with over 50% (v/v) wood fiber without lime showed a rapid pH increase over five weeks. The pour-through method generally underestimated EC values compared to the press method. These findings contribute to optimizing the wood fiber/peat blends for sustainable horticulture.

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Growth and flower bud initiation (FBI) were studied in single-stem plants of four biennial-fruiting cultivars in a controlled environment and under field conditions at 60°40′ N. Shoot growth varied widely among the cultivars but was significantly enhanced by high temperature (20 °C) in all cultivars, whereas photoperiod had a subordinate growth effect. FBI data from bud dissection after 6 weeks of cultivation in the phytotron were used to calculate FBI indices for the various cultivars and environment conditions. The indices also varied much among the cultivars but were enhanced by elevated temperature, being highest in ‘Natchez’ and ‘Sweet Royalla’, while ‘Natchez’ was the only cultivar in which FBI was significantly enhanced by short days. The non-vigorous and erect growing ‘Ouachita’ remained vegetative at both temperatures but flowered in spring after overwintering at 0.5 °C. The field experiment confirmed the superior growth vigor of ‘Loch Ness’ and ‘Sweet Royalla’ as well as the photoperiodic sensitivity of ‘Natchez’. The results also confirmed that floral initiation starts in lateral buds located 10–20 nodes below the apex, and from there it progresses in both acropetal and basipetal direction. We conclude that temperature is at least as important as the photoperiod for the control of FBI in biennial-fruiting blackberries.

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This paper presents some features of apple production in Norway, the northernmost apple-growing country in the world. Acceptable growing conditions prevail along the fjords in western Norway and around the lakes in eastern Norway at 60° north. These specific mesic climate conditions are associated with very long summer days (18 h daylight mid-summer) and short winter days (6 h daylight), with frost rarely occurring in the spring along the fjord areas. The present apple-growing technique in Norway is similar to that of other developed apple-growing countries, taking into account that all local growing phases involve a considerable delay in progress (1.5–2 months). Therefore, high-density planting systems based on the use of dwarf rootstocks (mainly M.9) with imported early maturing international apple cultivars are used in most orchards. The most common soil type has high organic matter content (2–18%), which persists due to the cool climate and low mineralization, and a clay content of <15%, which results from the formation of the soil from bedrock. The increase in average temperatures caused by current climatic changes leads to a complex combination of different physiological effects on apples, which can have positive or negative effects on the phenology of the trees. The main advantage of Norwegian apple production is that the quality and aroma of the fruit meet the current demands of the local market.

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Apples are a healthy and environmentally friendly snack, but the consumption of apples in many countries, including Norway, has decreased in the last fifteen years. This trend has a potential negative impact on public health and the environment. In this paper, we use a consumer survey and a random effect ordered logistic regression model to find out what is most important for people when they buy apples. Ten different values are considered and ranked according to individual’s importance. We find that taste and safety are the most important values for the average individual’s choice of apples, while the appearance and type of apple rank third. The least important values are wrapping size and regional origin. Everyday apple eaters are more concerned about pesticide use and less concerned about price than the average consumers. Furthermore, compared to the average consumer, those with low levels of trust in apple producers and authorities care more about pesticides and environmentally friendly production methods, while consumers with a high level of trust care less about these aspects. Our results indicate that to increase the consumption of Norwegian apples, it is important to maintain or improve their reputation as being tasty and safe to eat.

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The feed legislation allows the use of fish protein hydrolysates in feed for the same species in which it came from, since enzymatic hydrolysis degrades the proteins and eliminates potential prions, which have caused disease in mammals, but not in fish. In this trial, we investigated the effects of partially replacing dietary fishmeal (FM) with salmon protein hydrolysate (FPH) on the intestinal gene expression and microbiota. Atlantic salmon post smolts were either fed a control diet containing 30% fishmeal (FM), a 20% FM diet with 9% salmon hydrolysate (FPH-09) or a 10% FM diet with 18% salmon hydrolysate (FPH-18), until doubling of weight. Gene expression analysis by RNA sequencing of pyloric caeca (PC), midgut (MG) and hindgut (HG) revealed a downregulation of immunological genes involved in inflammation in the intestine of FPH-18 fed salmon compared to salmon fed the FM control. The gene expression of paralogous peptide transporters (PepT) was analyzed by real time quantitative PCR in PC, anterior midgut (AMG), posterior midgut (PMG) and HG of salmon fed all the three diets. The PepT1b paralog had highest relative expression levels in PC and AMG, suggesting that PepT1b is most important for peptide uptake in the anterior intestine. PepT1a was also mainly expressed in the PC and AMG, but at lower levels than PepT1b and PepT2b in the AMG. The PepT2b paralog had high levels of expression in AMG, PMG and HG indicating that it contributed significantly to peptide uptake in the posterior part of the gastrointestinal tract. The gut microbiota in the mucosa and digesta of the MG and HG, were dominated by the phyla Cyanobacteria and Proteobacteria, but also Firmicutes were present. The only dietary effect on the microbiota was the higher prevalence of the phyla Spirochaetes in the mucosa of FPH-18 fed salmon compared to the FM fed salmon. In conclusion, replacing FM with salmon hydrolysate reduced the expression of inflammatory markers in the Atlantic salmon intestine suggesting improved health benefits. The reduced inflammation may be related to the reduced FM content, potentially bioactive peptides in the hydrolysate and/or the altered gut microbial composition.

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Amphiboreal taxa are often composed of vicariant phylogroups and species complexes whose divergence and phylogeographic affinities reflect a shared history of chronic isolation and episodic trans-Arctic dispersal. Ecological filters and shifting selective pressures may also promote selective sweeps, niche shifts and ecological speciation during colonization, but these are seldom considered at biogeographical scales. Here we integrate genetic data and Ecologic Niche Models (ENMs) to investigate the historical biogeography and cohesion of the polymorphic rockweed Fucus distichus throughout its immense amphiboreal range, focusing on trans-Arctic asymmetries, glacial/interglacial dynamics, and integrity of sympatric eco-morphotypes. Populations were sampled throughout the Pacific and the Atlantic, from southern rear-edges to the high-Arctic. They were genotyped for seven microsatellites and an mtDNA spacer, and genetic diversity and structure were assessed from global to local scales. ENMs were used to compare niche divergence and magnitude of post-glacial range shifts in Pacific versus Atlantic sub-ranges. Haplotypic and genotypic data revealed distinct and seemingly isolated Pacific vs Arctic/Atlantic gene-pools, with finer-scale regional sub-structuring pervasive in the Pacific. MtDNA diversity was highly structured and overwhelmingly concentrated in the Pacific. Regionally, Alaska showed the highest intra-population diversity but the lowest levels of endemism. Some sympatric/parapatric ecotypes exhibited distinct genotypic/haplotypic compositions. Strikingly, niche models revealed higher Pacific tolerance to maximum temperatures and predicted a much more consolidated presence in the NE Atlantic. Glacial and modern ranges overlapped extensively in the Pacific, whereas the modern Atlantic range was largely glaciated or emerged during the Last Glacial Maximum. Higher genetic and ecogeographic diversity supports a primary Pacific diversification and secondary Atlantic colonization, also likely reflecting the much larger and more stable climatic refugia in the Pacific. The relic distribution and reduced ecological/morphological plasticity in the NE Atlantic are hypothesized to reflect functional trans-Arctic bottlenecks, recent colonization or competition with congeners. Within the Pacific, Alaska showed signatures of a post-glacial melting pot of eastern and southern populations. Genetic/ecotypic variation was generally not sufficiently discontinuous or consistent to justify recognizing multiple taxonomic entities, but support a separate species in the eastern Pacific, at the southern rear-edge. We predict that layered patterns of phylogeographic structure, incipient speciation and niche differences might be common among widespread low-dispersal amphiboreal taxa.

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Parasitic nematodes are ubiquitous and can negatively impact their host by reducing fecundity or increasing mortality, yet the driver of variation in the parasite community across a wildlife host's geographic distribution remains elusive for most species. Based on an extensive collection of fecal samples (n = 264) from GPS marked moose (Alces alces), we used DNA metabarcoding to characterize the individual (sex, age class) and seasonal parasitic nematode community in relation to habitat use and migration behavior in five populations distributed across a wide latitudinal gradient (59.6°N to 70.5°N) in Norway. We detected 21 distinct nematode taxa with the six most common being Ostertagia spp., Nematodirella spp., Trichostongylus spp., T. axei, Elaphostrongylus alces, and an unclassified Strongylida. There was higher prevalence of livestock parasites in areas with larger sheep populations indicating a higher risk of spillover events. The individual level nematode richness was mostly consistent across study areas, while the number and type of nematode taxa detected at each study area varied considerably but did not follow a latitudinal gradient. While migration distance affected nematode beta-diversity across all sites, it had a positive effect on richness at only two of the five study areas suggesting population specific effects. Unexpectedly, nematode richness was higher in winter than summer when very few nematodes were detected. Here we provide the first extensive description of the parasitic nematode community of moose across a wide latitudinal range. Overall, the population-specific impact of migration on parasitism across the distribution range and variation in sympatry with other ruminants suggest local characteristics affect host-parasite relationships.

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Background: Recycling nutrients and organic matter available as waste in urban areas may close nutrient gaps and improve soil quality, but the concentrations of potentially toxic elements (PTEs) are commonly higher than in mineral fertilisers. How quickly may the limits for soil quality be exceeded, and for which elements, if such materials are applied intensively? For a rough answer to this question, we used soil data from ten case farms near Oslo and Bergen (Norway) to estimate how PTE concentrations increased when the demand for nitrogen (N), phosphorus (P) and potassium (K) in a theoretical carrot crop produced every year was covered by compost or digestate from source‑separated food waste, or composted garden waste, compared with manure from horses and poultry which are often kept in peri‑urban areas. Results: With the intensive fertilisation assumed here, the Norwegian soil quality limits for PTEs were reached within 20–85 years, and faster for soil with more organic matter since regulatory limits set by weight discriminate soils with low bulk density. The limits were reached first for Cu and Zn, which are both essential micronutrients for crop plants. The concentrations of macronutrients in the urban waste‑based fertilisers were not well balanced. Rates covering the K demand would lead to high surpluses of P and N. In peri‑urban vegetable growing, high applications of compost are not unusual, but more balanced fertilisation is required. Conclusions: The Norwegian regulations for PTEs in organic soil amendments and agricultural soil are stricter than in the EU, and do not support recycling of organic matter and nutrients from urban waste. Many materials which can only be applied with restricted amounts to Norwegian agricultural soil, may be applied according to crop demand in the EU. Growers utilising urban waste‑based fertilisers intensively should monitor the soil regularly, including PTE analyses. Soil sampling should occur on fixed sampling points to reveal changes in concentrations over time. Norwegian authorities should consider a revision of the organic fertiliser regulation to support recycling of valuable organic materials. There is a need for more data on the PTE concentrations in agricultural soil and organic fertiliser materials. Keywords Cadmium, Copper, Zinc, Smallscale vegetable growing, Food wastes, Urban agriculture, Compost, Digestate

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Soybean pod count is a crucial aspect of soybean plant phenotyping, offering valuable reference information for breeding and planting management. Traditional manual counting methods are not only costly but also prone to errors. Existing detection-based soybean pod counting methods face challenges due to the crowded and uneven distribution of soybean pods on the plants. To tackle this issue, we propose a Soybean Pod Counting Network (SPCN) for accurate soybean pod counting. SPCN is a density map-based architecture based on Hybrid Dilated Convolution (HDC) strategy and attention mechanism for feature extraction, using the Unbalanced Optimal Transport (UOT) loss function for supervising density map generation. Additionally, we introduce a new diverse dataset, BeanCount-1500, comprising of 24,684 images of 316 soybean varieties with various backgrounds and lighting conditions. Extensive experiments on BeanCount-1500 demonstrate the advantages of SPCN in soybean pod counting with an Mean Absolute Error(MAE) and an Mean Squared Error(MSE) of 4.37 and 6.45, respectively, significantly outperforming the current competing method by a substantial margin. Its excellent performance on the Renshou2021 dataset further confirms its outstanding generalization potential. Overall, the proposed method can provide technical support for intelligent breeding and planting management of soybean, promoting the digital and precise management of agriculture in general.

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Agricultural soil has great potential to address climate change issues, particularly the rise in atmospheric CO2 levels. It offers effective remedies, such as increasing soil carbon content while lowering atmospheric carbon levels. The growing interest in inoculating soil with live microorganisms aims to enhance agricultural land carbon storage and sequestration capacity, modify degraded soil ecosystems, and sustain yields with fewer synthetic inputs. Agriculture has the potential to use soil microalgae as inoculants. However, the significance of these microorganisms in soil carbon sequestration and soil carbon stabilization under field conditions has yet to be fully understood. Large-scale commercial agriculture has focused on the development and use of inoculation products that promote plant growth, with a particular emphasis on enhancing yield attributes. Gaining more profound insights into soil microalgae’s role in soil carbon cycling is necessary to develop products that effectively support soil carbon sequestration and retention. This review comprehensively explores the direct and indirect mechanisms through which soil microalgae contribute to soil carbon sequestration, highlighting their potential as microbial inoculants in agricultural settings. This study underlines the need for more research to be conducted on microalgae inoculation into agricultural soil systems aimed at mitigating carbon emissions in the near future.

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Sweet potato (Ipomoea batatas L. Lam.) is a major source of food in many parts of Ethiopia. In recent years, viral diseases have become the main threat to sweet potato production in Ethiopia. Previous virus survey studies carried out from 1986 to 2020 reported eight viruses infecting sweet potato in Ethiopia. Consequently, obtaining and multiplying virus-free planting materials have been difficult for farmers and commercial multipliers. This study was conducted to detect viruses infecting the five sweet potato varieties used as source plants and compare the virus elimination efficiency between meristem cultures from untreated and heat-treated mother plants and production of virus-free sweet-potato-planting materials. Seven common viruses were tested for, using grafting to Ipomoea setosa, enzyme-linked immunosorbent assay (ELISA) and reverse-transcription polymerase chain reaction (RT–PCR) before and after elimination procedures as screening and confirmatory methods. The sweet potato feathery mottle virus (SPFMV) elimination efficiencies of meristem cultures from untreated (grown at 25 ± 1 °C) and heat-treated (grown at 39 ± 1 °C) potted plants of sweet potato varieties were evaluated and compared. Sweet potato feathery mottle virus (SPFMV) was detected in 12 of the 15 source plants tested. Triple infections of SPFMV, sweet potato chlorotic stunt virus (SPCSV), and sweet potato virus C (SPVC) were detected in one of the fifteen plants. This study reports the detection of SPVC for the first time in sweet potato plants from Ethiopia. The cutting of meristems from heat-treated plants further increased the percentage of virus-free plantlets by ca 10% to ca 16%, depending on the plant variety. Elimination efficiency also seemed to vary among varieties: the greatest difference was observed for ‘Tola’, and the least difference was observed for ‘Guntute’. The present study provided protocols for detecting viruses and generating virus-free sweet-potato-planting materials in Ethiopia.

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The birth process in animals, much like in humans, can encounter complications that pose significant risks to both offspring and mothers. Monitoring these events can provide essential nursing support, but human monitoring is expensive. Although there are commercial monitoring systems for large ruminants, there are no effective solutions for small ruminants, despite various attempts documented in the literature. Inertial sensors are very convenient given their low cost, low impact on animal life, and their flexibility for monitoring animal behavior. This study offers a systematic review of the literature on detecting parturition in small ruminants using inertial sensors. The review analyzed the specifics of published research, including data management and monitoring processes, behaviors indicative of parturition, processing techniques, detection algorithms, and the main results achieved in each study. The results indicated that some methods for detecting birth concentrate on classifying unique animal behaviors, employing diverse processing techniques, and developing detection algorithms. Furthermore, this study emphasized that employing techniques that include analyzing animal activity peaks, specifically recurrent lying down and getting up occurrences, could result in improved detection precision. Although none of the studies provided a completely valid detection algorithm, most results were promising, showing significant behavioral changes in the hours preceding delivery.

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The growth of the aquaculture industry requires more sustainable and circular economy-driven aquafeed formulas. Thus, the goal of the present study was to assess in farmed gilthead sea bream (Sparus aurata L.) how different combinations of novel and conventional fish feed ingredients supported proper animal performance in terms of growth and physiological biomarkers of blood/liver/head kidney. A 77-day feeding trial was conducted with three experimental diets (PAP, with terrestrial processed animal protein from animal by-products; NOPAP, without processed animal protein from terrestrial animal by-products; MIX, a combination of alternative ingredients of PAP and NOPAP diets) and a commercial-type formulation (CTRL), and their effects on growth performance and markers of endocrine growth regulation, lipid metabolism, antioxidant defense and inflammatory condition were assessed at circulatory and tissue level (liver, head kidney). Growth performance was similar among all dietary treatments. However, fish fed the PAP diet displayed a lower feed conversion and protein efficiency, with intermediate values in MIX-fed fish. Such gradual variation in growth performance was supported by different biomarker signatures that delineated a lower risk of oxidation and inflammatory condition in NOPAP fish, in concurrence with an enhanced hepatic lipogenesis that did not represent a risk of lipoid liver degeneration.

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The abundance and diversity of antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) in agricultural landscapes may be important for the spread of antimicrobial resistance (AMR) in the environment. The aim of this study was to apply screening methods for ARB and ARGs to investigate the impact of farming on the prevalence of AMR in a country with low antibiotic usage. We have analyzed samples (n = 644) from soil and wild terrestrial animals and plants (slugs, snails, mice, shrews, earthworms, and red clover) collected over two years in agricultural fields accompanied by nearby control areas with low human activity. All samples were investigated for the occurrence of 35 different ARGs using high-throughput quantitative PCR (HT-qPCR) on a newly developed DNA array. In addition, samples from the first year (n = 415) were investigated with a culture-based approach combined with whole-genome sequencing (WGS) to identify antimicrobial-resistant E. coli (AREC). ARGs were detected in 59.5% of all samples (2019 + 2020). AREC, which was only investigated in the 2019 samples, was identified in 1.9% of these. Samples collected in the autumn showed more ARGs and AREC than spring samples, and this was more pronounced for organic fields than for conventional fields. Control areas with low human activity showed lower levels of ARGs and a lack of AREC. The use of livestock manure was correlated with a higher level of ARG load than other farming practices. None of the soil samples contained antibiotics, and no association was found between AMR and the levels of metals or pesticides. High qualitative similarity between HT-qPCR and WGS, together with the positive controls to the validation of our 35 ARG assays, show that the microfluid DNA array may be an efficient screening tool on environmental samples. In conclusion, even in a country with a very low consumption of antimicrobials by production animals, our results support the hypothesis of these animals being a source of AREC and ARGs in agricultural environments, primarily through the use of manure.

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Mapping and quantification of forest biomass change are key for forest management and for forests’ contribution to the global carbon budget. We explored the potential of covering this with repeated acquisitions with TanDEM-X. We used an eight-year period in a Tanzanian miombo woodland as a test case, having repeated TanDEM-X elevation data for this period and repeated field inventory data. We also investigated the use of GEDI space–LiDAR footprint AGB estimates as an alternative to field inventory. The map of TanDEM-X elevation change appeared to be an accurate representation of the geography of forest biomass change. The relationship between TanDEM-X phase height and above-ground biomass (AGB) could be represented as a straight line passing through the origin, and this relationship was the same at both the beginning and end of the period. We obtained a similar relationship when we replaced field plot data with the GEDI data. In conclusion, temporal change in miombo woodland biomass is closely related to change in InSAR elevation, and this enabled both an accurate mapping and quantification wall to wall within 5–10% error margins. The combination of TanDEM-X and GEDI may have a near-global potential for estimation of temporal change in forest biomass.

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Gaining the ability to fly actively was a ground-breaking moment in insect evolution, providing an unprecedented advantage over other arthropods. Nevertheless, active flight was a costly innovation, requiring the development of wings and flight muscles, the provision of sufficient energetic resources, and a complex flight control system. Although wings, flight muscles, and the energetic budget of insects have been intensively studied in the last decades, almost nothing is known regarding the flight-control devices of many crucial insect groups, especially beetles (Coleoptera). Here, we conducted a phylogenetic-informed analysis of flight-related mechanosensors in 28 species of bark beetles (Curculionidae: Scolytinae, Platypodinae), an economically and ecologically important group of insects characterized by striking differences in dispersal abilities. The results indicated that beetle flight apparatus is equipped with different functional types of mechanosensors, including strain- and flow-encoding sensilla. We found a strong effect of allometry on the number of mechanosensors, while no effect of relative wing size (a proxy of flight investment) was identified. Our study constitutes the first step to understanding the drivers and constraints of the evolution of flight-control devices in Coleoptera, including bark beetles. More research, including a quantitative neuroanatomical analysis of beetle wings, should be conducted in the future.>

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Common scab (CS) is a major bacterial disease causing lesions on potato tubers, degrading their appearance and reducing their market value. To accurately grade scab-infected potato tubers, this study introduces “ScabyNet”, an image processing approach combining color-morphology analysis with deep learning techniques. ScabyNet estimates tuber quality traits and accurately detects and quantifies CS severity levels from color images. It is presented as a standalone application with a graphical user interface comprising two main modules. One module identifies and separates tubers on images and estimates quality-related morphological features. In addition, it enables the extraction of tubers as standard tiles for the deep-learning module. The deep-learning module detects and quantifies the scab infection into five severity classes related to the relative infected area. The analysis was performed on a dataset of 7154 images of individual tiles collected from field and glasshouse experiments. Combining the two modules yields essential parameters for quality and disease inspection. The first module simplifies imaging by replacing the region proposal step of instance segmentation networks. Furthermore, the approach is an operational tool for an affordable phenotyping system that selects scab-resistant genotypes while maintaining their market standards.

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Northern European heathlands and moorlands dominated by Calluna vulgaris are internationally recognized for their conservation importance while also supporting traditional, low-intensity agriculture and game hunting. Managed burning plays an important role in maintaining these ecosystems but climate and land-use changes, including planned or unplanned transitions to forest and woodland, are now resulting in concerns about increasing wildfire frequency, intensity and severity. In combination with rapidly-changing regulations surrounding managed burning, this has highlighted the need to understand current and potential future fuel structures to effectively model fire behaviour and develop evidence-based regulations surrounding managed burning. We developed standardized heathland fuel descriptions and modeled associated fire behaviour for heathlands in the UK (England, Scotland) and Norway. Utilizing existing fuel and biomass data, we used cluster analysis to identify five distinct fuel models and assessed how they were represented across C. vulgaris life-stages, geographic locations and EUNIS habitat-types. We validated their independence by examining predicted fire rates of spread based across three representative fire weather scenarios. Fire rates of spread differed between C. vulgaris life stages, regardless of EUNIS community or country. Mature stage and taller building stage fuels produced the highest fire rates of spread and early, shorter building and pioneer stage fuels produced the lowest. Moss and litter fuel loads proved to be important determinants of fire rate of spread in a high-risk fire weather scenario. An understanding of links between fuel types and potential fire behaviour can be used to inform management and policy decisions. To aid in this, we used classification tree analysis to link fuel types to easily-observable characteristics. This will facilitate pairing the fuel models with fire behaviour prediction software to make evidence-based assessments of management fire safety and wildfire risk.

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Interest in dairy cow-calf contact (CCC) systems is growing, yet limited research had been focused on CCC in a pasture setting. Our study aimed to evaluate the performance of pastured dairy cows and calves with or without CCC through machine milk yield and composition, cow body condition score (BCS) and body weight (BW) decrease, and calf body weight gain (BWG). We also examined calf intake of concentrates, artificially reared calves’ milk intake, and the health of both cows and calves. Conducted on a commercial dairy freestall farm and summer farm in Norway from May to August 2021, the study included twenty cow-calf pairs: 17 Norwegian Red (NRF) and three NRF × Holstein crossbreeds. They were divided into two treatments: cow-calf contact (CC, n = 10) or early separation (ES, n = 10), each with two groups of five cow-calf pairs. CC pairs had full CCC on pasture until 6 weeks postpartum and part-time contact in weeks 7 and 8 (weaning). ES pairs were separated 1–3 h after birth, kept on separate pastures with no contact between ES cows and calves. ES calves’ received daily milk allowances of 12–14 L (weeks 0–6), reduced to 8 L (week 7) and further to 4 L (week 8). From week 9, all calves were denied access to any milk (ES) or cows (CC). During weeks 0–6, CC cows had a daily machine milk yield 23.7 kg lower/cow than ES cows. The difference was likely affected by nursing and other factors (parity and inhibited milk ejection), and persisted during weaning, with CC cows delivering 8.3 kg less/cow/day in weeks 10 and 11 postpartum. Fat and protein content in machine milk showed no significant difference, while lactose content was lower in milk from CC cows than ES cows (week 5 postpartum). CC cows had a lower BW decrease compared to ES cows (CC: 913 g/day, ES: 1415 g/day from pasture day one through week 9). ES calves had an average milk intake of 10.7 L/calf/day (weeks 0–6), and consumed more concentrates than CC calves. Calves’ daily BWG did not differ between treatments in weeks 0–6 (CC: 1340 and ES: 1250 g/day) and decreased for both treatments during weaning (CC: 1050 g/day, ES: 920 g/day in weeks 6–9). Inhibited milk ejection during machine milking was a challenge in CC cows, prompting oxytocin injections to prevent mastitis. Allowing calves full CCC or providing whole milk near ad libitum can result in similar BWG and health in calves. Further research should explore strategies to enhance milk ejection in pastured CCC cows.

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Studies have shown that extended wilting of grass before ensiling can improve the metabolizable protein (MP) value of the grass silage, both from increased rumen microbial crude protein (MCP) yield and ruminally undegraded crude protein (RUP). We hypothesised that extending the wilting of grass before ensiling can increase milk and milk protein production in dairy cows. Consequently, increased silage MP can reduce the need for MP in concentrate, estimated as amino acids absorbed in the small intestine (AAT20). To test this, a continuous feeding experiment was conducted, with 48 early- to mid-lactation Norwegian Red dairy cows. Treatments were 2 wilting levels of grass silages: 260 vs. 417 g dry matter (DM) per kg, and 2 qualities of concentrates differing in MP, in a 2 × 2 factorial arrangement (n = 12). The concentrates were low MP (LMP); 104 g AAT20/kg DM, and high MP (HMP); 123 g AAT20/kg DM, supplied at 8.75 kg DM/cow per day. The cows had ad libitum access to the grass silages. The experiment lasted for 11 weeks. The first 2 weeks, where cows received identical diets, were used as the covariate period. Those data together with data collected the last 4 weeks were used for statistical evaluation of treatments. Increasing DM concentration in silage reduced lactic acid, ammonia nitrogen and proportion of methionine in the grass silage, while it increased residual water-soluble carbohydrates, pH, proportion of aspartic acid and rumen degradability of NDF. There was no difference between treatments in daily silage DM intake (13.1 kg), milk yield (30.2 kg) or milk composition. However, feeding HMP increased urea and uric acid in urine, and urea in blood plasma, thereby reduced N efficiency. No major differences were found for rumen pH, or purine derivatives to creatinine index in urine, as indication for MCP. There was significantly more histidine in blood plasma when cows were fed HMP concentrate. In conclusion, increased DM concentration in silage and HMP concentrate did not increase milk production or milk protein yield in this study.

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Biochar is a recalcitrant carbon-rich solid produced by pyrolysis of organic residues, and its application to soil is considered a promising approach to mitigate climate change, as biochar resists decomposition to readily contributes to soil carbon (C) sequestration. The IPCC provides a basis for future national-scale accounting of the changes in soil C stocks following biochar application to cropland soils. The IPCC Tier 1 approach for biochar is based on fixed emission factors to estimate biochar C sequestration. In contrast, the Tier 2 approach allows countries to use local emission factors and climate data to calculate the contribution of biochar to soil C sequestration. Accurate accounting of biochar C sequestration is essential for ensuring the credibility of C offsetting projects, as well as providing incentives for implementing biochar in C credit schemes, calling for comparative analyses of the different biochar Tier approaches. Here we retrieved biochar samples from local producers and measured their H/Corg to estimate the persistence of biochar in Norwegian croplands post application. Various feedstocks were considered, including forest residues, woody wastes, manure, sludge, and straw. For all biochar samples, the 100-year stable C fraction was calculated at ≥ 0.945, thus exceeding the default Tier 1 value (0.8). Biochar sourced from woody- and forestry residues had a Corg content above the default Tier 1 value (0.77). Based on this and data about national feedstock supplies, we compared the theoretical potential of biochar soil C sequestration to mitigate climate change in Norway, using the IPCC Tier 1 and Tier 2 approaches. Biochar C sequestration in soil was calculated at 0.79 Tg CO2-eq yr−1 and 0.92 to 0.96 Tg CO2-eq yr−1, respectively for the Tier 1 and Tier 2 approaches, thus, underlining that the choice of IPCC Tier approach can have a large impact on the estimated mitigation potential of biochar.

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The ability to identify locations that have a high risk of fungal decay is important for service life planning and analysing changes in risk can help inform scenarios where climate change may shift some areas into states that are more suitable for decay. The ERA5-Land database was used to obtain soil moisture and temperature data, which was applied in a dose–response model for in-ground wood decay. Dose was used as an indicator of decay risk and to produce hazard maps over Germany for the past two climate normals (1963–1992 and 1993–2022). There was an increase of 3.16 dose days over Germany. Brandenburg and Mecklenburg-Vorpommern, had the highest decay risk in both climate normals and southern states experienced the lowest decay risk. In Germany, larger dose increases were seen in central to southern latitude regions and mid to high altitudes. With further climate change, conditions that are most suitable for in-ground wood decay may shift to locations that previously did not experience such risk. It is important to be informed of the durability requirements of wood products in areas where increased resistance may be required.

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This study investigated the potential of wood particles from Ciol®-treated wood in particleboard production. Ciol® is a renewable formulation from water, citric acid, and sorbitol, which has been commercially developed as a promising alternative for wood modification. Radiata pine wood was impregnated with 60% and 85% concentrations of the Ciol® solution for 150 mins. The impregnated boards were cured and subsequently planned. Particleboards were thereafter produced from the wood shavings using urea formaldehyde (UF) and melamine urea formaldehyde resin (MUF). The boards were produced with or without the use of ammonium nitrate as a hardener. The wood particles and produced boards were characterized via analytical techniques and standard test methods. The effect of Ciol® treatment and its concentration on the properties of the shavings and the particleboards was investigated as well as the effect of the resin type on the panel properties. The use of MUF without the hardener gave the best bending strength of 13 N/mm² and modulus of elasticity of 3187 N/mm². However, there was no significant difference in the results obtained when the hardener was added to MUF resins. Recycling Ciol®-treated wood shavings in particleboard production proved to be a promising approach with MUF resins.

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Plant reproduction in alpine environments is affected by climate both directly through climate impacts on growth and phenology, and indirectly through impacts on the biotic interactions affecting pollination success. These effects can be highly variable in time and space. In this study we investigated how different abiotic and biotic factors influence reproductive investment and success in populations of Ranunculus acris across an alpine landscape over a two-year period. In an alpine area at Finse, southern Norway, we measured reproductive investment (total seed mass) and reproductive success (seed-set rate) in 38 sites differing in temperature (related to elevation) and length of the growing season (related to time of snowmelt). To assess biotic interactions, we measured floral density and pollinator visits and conducted a supplemental pollen experiment. Reproductive investment and success increased with temperature, but only when floral density and/or number of pollinator visits was high, and only in the warmer year (2016). Reproduction in R. acris was pollen-limited in both years, especially at warmer temperature and in sites with early snowmelt. Pollinator visits increased with temperature and with higher floral density, suggesting a shift in relative importance of the biotic factors (from plants to pollinators) in limiting reproduction with increasing temperature. Our study shows that reproductive investment and success in R. acris is affected by climate through the interactive effects of abiotic and biotic processes. These effects vary between years and across the landscape, suggesting a potential for larger-scale buffering of climate change effects in heterogeneous landscapes.

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With the intensification of global climate change and environmental stress, research on abiotic and biotic stress resistance in maize is particularly important. High temperatures and drought, low temperatures, heavy metals, salinization, and diseases are widespread stress factors that can reduce maize yields and are a focus of maize-breeding research. Molecular biology provides new opportunities for the study of maize and other plants. This article reviews the physiological and biochemical responses of maize to high temperatures and drought, low temperatures, heavy metals, salinization, and diseases, as well as the molecular mechanisms associated with them. Special attention is given to key transcription factors in signal transduction pathways and their roles in regulating maize stress adaptability. In addition, the application of transcriptomics, genome-wide association studies (GWAS), and QTL technology provides new strategies for the identification of molecular markers and genes for maize-stress-resistance traits. Crop genetic improvements through gene editing technologies such as the CRISPR/Cas system provide a new avenue for the development of new stress-resistant varieties. These studies not only help to understand the molecular basis of maize stress responses but also provide important scientific evidence for improving crop tolerance through molecular biological methods.

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Floral initiation in biennial-fruiting red raspberry is controlled by the interaction of temperature and photoperiod. To determine the threshold temperatures for short day (SD) floral initiation in early- and late-flowering cultivars, we exposed plants of ‘Glen Ample’, ‘Glen Mor’ and ‘Duo’ to 12°, 16° and 20°C in a daylight phytotron under naturally decreasing autumn daylength at Ås, Norway (59°40’N). While none of the cultivars ceased growing or initiated floral primordia at 20°C, ‘Glen Ample’ and ‘Glen Mor’ initiated buds at 12° and 16°C, whereas ‘Duo’ formed flower buds at 12°C only. Surprisingly, however, all plants flowered abundantly in spring after winter chilling in the dark at −1.5 ± 0.5°C for 7 months. We discuss two possible explanations for this unusual and novel flowering response. Fractional induction is well known in raspberry, and we visualise that in SD at 20°C, the SD requirement is fulfilled, while floral induction is still blocked by inappropriate temperature. A vernalisation-like response is alternatively suggested as this can take place at near-freezing temperatures in the dark. A combination of the two mechanisms is also possible and likely. We conclude, however, that the two floral induction processes are fundamentally different and controlled by different physiological mechanisms.

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Background Vegetated infiltration systems such as raingardens and bioswales are challenging for plant growth and survival due to fluctuating hydrological conditions and further subsequent stresses. Aim Here, we investigated the effect of fluctuation hydrology on growth and flowering and subsequent winter frost hardiness or spring salt tolerance for two common raingarden plant species, Filipendula ulmaria, and Calamagrostis ×acutiflora ‘Karl Foerster’, under controlled conditions. Methods During summer, plants were exposed to four hydrological regimes, each with a different combination of repeating dry and wet cycles. Then, after natural winter acclimation and storage, plants went through standardized freezing tests to determine LT50 and regrowth potential or were exposed to four levels of salt treatments (Control, 28 mM, 56 mM, and 84 mM NaCl) in the following spring. Results We found that fluctuating hydrology reduced the growth of Filipendula ulmaria, experiencing cycles of 72 hours of flooding and 264 hours of drained conditions, followed by a reduction of growth and flowering after salt exposure. Calamagrostis xacutiflora was less responsive to both fluctuating hydrology and salinity. Cycles with the longest dry conditions (Wet-dry cycles) showed the strongest negative effect on the performance of tested species. The hydrological regimes did not influence freezing tolerance in either species. Conclusion Moderate hydrological fluctuations did not cause damage to vegetation in vegetated infiltration systems, at least under shaded conditions. At the same time, drought tolerance is an important trait for species and cultivars in raingardens during hydrological fluctuations. Our prediction that hydrological conditions that negatively affected plant growth would reduce subsequent frost and salinity tolerance was only partially supported.

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In Europe, over a third of the agricultural area is grass meadows used for livestock grazing and fodder production. Grass meadows provide a food source for wild ungulates causing human-wildlife conflicts due to forage removal. Few experimental studies have quantified biomass loss with enough replicates to determine how surrounding environments influences level of biomass removal. Using an exclosure experiment on 57 grassland meadows over five years at the northwest coast of Norway covering 10 650 km2, we quantified biomass removal by red deer (Cervus elaphus L.) and how environmental factors impacted biomass loss (Study 1). Furthermore, we examined development of biomass loss and crude protein concentration in five fields throughout the growing season (Study 2). The average predicted biomass loss to red deer grazing was 16% for the first harvest, and 7.3% for the second harvest (Study 1). Biomass loss increased with red deer density from 0% at the lowest density (0.6 red deer harvested/km2) to 31% at the highest density (4 red deer harvested/km2). Biomass loss increased from 12% to 32.8% as terrain ruggedness index (TRI) rose from 2.1 to 7.1. Absolute biomass loss increased towards time of grass harvest (Study 2). Crude protein concentration was higher in unfenced plots during the period before first harvest, but not between first and second harvest (Study 2). The quantification of biomass removal at a large spatial scale over several years in this study provides a better understanding of factors causing variation in losses.

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Cultivation of microalgae has gained significant interest as an alternative protein source, potentially becoming a target commodity recovered from microalgae-based wastewater treatment. This study examined a semi-continuous cultivation strategy to optimize protein accumulation of the indigenous freshwater chlorophytes, Lobochlamys segnis and Klebsormidium flaccidum, and simultaneously remove nutrients from wastewater efficiently. A strain-specific regime was made based on a fixed biomass concentration at the start of 24-h cultivation cycle, i.e., a constant initial cell density, which regulated harvesting and fresh medium supply volume according to the dilution rate. Six cultivation cycles were conducted in lab-scale 1L reactors with a synthetic municipal wastewater. Lobochlamys segnis and K. flaccidum grew exponentially in all cycles. The biomass productivity was 573 and 580 mg L–1 day–1, in which the total protein consisted of 62 and 45% of dry cell weight (dw), respectively. When a culture medium deficient in nitrogen and phosphorus was used, protein level was significantly reduced. L. segnis consumed all NH4+ and PO43– supplied by the medium replacement, giving the removal rate of 9.2 and 5.2 mg L–1 day–1. Whereas K. flaccidum removed 13.8 mg L–1 day–1 NH4+ without completing PO43– removal. The amino acid profile of both strains was characterized by glutamic acids content (4–5% dw). We concluded that the designed cultivation regime would support a constant biomass production with stable and high protein content, along with an efficient removal of nutrient from the wastewater.

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The brown marine macroalga Alaria esculenta contains phlorotannins as polyphenolic compounds in its cell walls. This study aimed to understand their antioxidant effects on preserving the lipids in fillets of freshly-slaughtered farmed Atlantic salmon (Salmo salar). First, soluble phlorotannins were extracted from wild-grown population of A. esculenta in North Norway (Bodø) using solid/liquid extraction. A small-scale solid/liquid extraction (15 mg mL−1) with 70% acetone showed that 84% of total soluble phlorotannins (25.10 mg g−1 dry weight) were extracted after the first out of four extraction steps. In a large-scale extraction (3 mg 400 mL−1), the contents of soluble phlorotannins and the DPPH-based antioxidant capacities (measured as IC50) in 70% acetone- and water-based crude extracts were similar. Water is preferred extraction solvent for the following experiment because it complies with food safety standards, may minimise work procedures and is in accordance with the principles of Green Chemistry. Secondly, the antioxidant properties of the soluble phlorotannins were tested through incubating salmon fillets (Norwegian Quality Cuts) in water-based extracts. After six days of storage on ice, the peroxide value of Alaria-treated fillets was lower compared to the control (without Alaria-extract), while the p-anisidine and free fatty acid values remained unchanged. This indicates the phlorotannins’ inhibitory effect on the formation of primary rather than secondary lipid oxidation products. This study demonstrated that the antioxidant properties of the soluble phlorotannins extracted from A. esculenta using water can preserve the nutritional value of salmon fillets to extend the seafood’s shelf-life.

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Background Potato virus Y (PVY) is among the economically most damaging viral pathogen in production of potato (Solanum tuberosum) worldwide. The gene Rysto derived from the wild potato relative Solanum stoloniferum confers extreme resistance to PVY. Results The presence and diversity of Rysto were investigated in wild relatives of potato (298 genotypes representing 29 accessions of 26 tuber-bearing Solanum species) using PacBio amplicon sequencing. A total of 55 unique Rysto-like sequences were identified in 72 genotypes representing 12 accessions of 10 Solanum species and six resistant controls (potato cultivars Alicja, Bzura, Hinga, Nimfy, White Lady and breeding line PW363). The 55 Rysto-like sequences showed 89.87 to 99.98% nucleotide identity to the Rysto reference gene, and these encoded in total 45 unique protein sequences. While Rysto-like26 identified in Alicja, Bzura, White Lady and Rysto-like16 in PW363 encode a protein identical to the Rysto reference, the remaining 44 predicted Rysto-like proteins were 65.93 to 99.92% identical to the reference. Higher levels of diversity of the Rysto-like sequences were found in the wild relatives of potato than in the resistant control cultivars. The TIR and NB-ARC domains were the most conserved within the Rysto-like proteins, while the LRR and C-JID domains were more variable. Several Solanum species, including S. antipoviczii and S. hougasii, showed resistance to PVY. This study demonstrated Hyoscyamus niger, a Solanaceae species distantly related to Solanum, as a host of PVY. Conclusions The new Rysto-like variants and the identified PVY resistant potato genotypes are potential resistance sources against PVY in potato breeding. Identification of H. niger as a host for PVY is important for cultivation of this plant, studies on the PVY management, its ecology, and migrations. The amplicon sequencing based on PacBio SMRT and the following data analysis pipeline described in our work may be applied to obtain the nucleotide sequences and analyze any full-length genes from any, even polyploid, organisms. Keywords Amplicon sequencing, AmpSeq, Extreme resistance, Hyoscyamus niger, PacBio, Physalis peruviana, PVY, Solanum

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Forest age structure is one of the most important ecological indicators of forest sustainability in terms of biodiversity, forest history, harvesting potentials, carbon storage, and recreational values. The available information on the forest age is most often stand age from forest management plans or national forest inventories. Depending on the definition, stand age is often not a good indicator for the biological age of the dominant trees in a stand. Here, we used 6,998 increment cores from dominant Norway spruce (Picea abies L.) and Scots pine (Pinus sylvestris L.) sampled on National Forest Inventory (NFI) plots throughout Norway to gain a better understanding of the age structure of Norway spruce and Scots pine stands in Norway, and on the relationship between the recorded stand age and the biological age of dominant trees on the NFI plots. In forest with stand ages indicating that the stand was established after the abandonment of selective harvesting in favor of even-aged management dominated by clear-cutting methods (ca.1940 C.E.), we found no systematic difference between the biological age of the sampled trees and the stand age assessed by the NFI. In older stands, there was a large difference between the stand age and the age of the overstory trees with the sampled age trees occasionally being hundreds of years older than the stand age. Our study also reveals that the area of forest with old Norway spruce and Scots pine trees ≥ 160 years old is considerably higher than the corresponding area estimate based on information derived from the stand age only. These results are important as the stand age is often used to characterize status with respect to forest naturalness, biodiversity, guide protection efforts, and describe the appropriate and allowed management activities.

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Over the past four decades, an increase in Dissolved Natural Organic Matter (DNOM) and colour, commonly referred to as browning, has been noted in numerous watercourses in the northern hemisphere. Understanding the fluctuations in DNOM quality is a prerequisite for gaining insights into the biogeochemical processes governing DNOM fluxes. Such knowledge is also pivotal for water treatment plants to effectively tailor their strategies for removing DNOM from raw water. The specific ultraviolet absorbance (sUVa) index has been a widely applied measurement for assessing DNOM quality. The sUVa index is the UV absorbance (OD254) of water normalized for DNOM concentration. We have used a long-term dataset spanning from 2007 to 2022, taken from the Malše River in South Bohemia, to model DNOM and the sUVa index. We have applied regression models with a process-oriented perspective and have also considered the influence of climate change. Both DNOM and the sUVa index is positively related to temperature, runoff and pH, and negatively related to ionic strength over the studied period. Two distinct model approaches were employed, both explaining about 40% of the variation in sUVa over the studied period. Based on a moderate IPCC monthly climate scenario, simulations indicate that both DNOM and the sUVa index averages remain fairly stable, with a slight increase in winter season minima projected towards the year 2099. A slight decline in summer season maxima is simulated for DNOM, while the sUVa summer maximum remain stable. These findings suggest a robust resilience in both DNOM and the sUVa index against anticipated changes in temperature and runoff for the Malše River in South Bohemia.

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In this study, 200 Norwegian dairy farms were analyzed over three years to compare greenhouse gas emissions, nitrogen (N) intensity, gross margin, and land use occupation between organically and conventionally managed farms. Conventionally managed farm groups were constructed based on propensity matching, selecting the closest counterparts to organically managed farms (n=15). These groups, each containing 15 farms, were differentiated by an increasing number of matching variables. The first group was matched based on geographical location, milk quota, and milking cow units. In the second match, the proportion of milking cows in the total cattle herd was added, and in the third, the ratio of milk delivered to milk produced and concentrate usage per dairy cow were included. The analysis showed that the conventionally managed farms (n=185) had higher greenhouse gas emissions (1.42 vs 0.98 kg CO2 per 2.78 MJ of edible energy from milk and meat, calculated as GWP100-AR4) and higher N intensity (6.9 vs 5.0 kg N input per kg N output) compared to the organic farms (N=15). When comparing emissions per kg of energy-corrected milk (ECM) delivered, conventional farms also emitted more CO2 (1.07 vs 0.8 kg CO2 per kg ECM). Furthermore, conventionally managed farms showed lower gross margins both in terms of NOK per 2.78 MJ edible energy delivered (5.8 vs 6.5 NOK) and per milking cow unit (30 100 vs 34 400 NOK), and they used less land (2.9 vs 3.6 m² per 2.78 MJ edible energy delivered) compared to organic farms. No differences were observed among the three conventionally managed groups in terms of emissions, N intensity, land use occupation, and gross margin.

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Soil management strategies involving the application of organic matter (OM) inputs (crop residues, green and livestock manure, slurry, digestate, compost and biochar) can increase soil carbon storage but simultaneously lead to an increase in non-CO2 greenhouse gas (GHG) emissions such as N2O. Although multiple meta-analyses have been conducted on the topic of OM input impacts on GHG, none has focused specifically on European arable soils. This study plugs this gap and can assist policymakers in steering European agriculture in a more sustainable direction. The objective of this meta-analysis was to quantify how OM inputs of different nature and quality, but also the application strategy, can mitigate soil N2O emissions in different pedoclimatic conditions in Europe. We quantitatively synthesised the results of over 50 field experiments conducted in 15 European countries. Diverse arable crops, mainly cereals, were cultivated in monoculture or in crop rotations on mineral soils. Cumulative N2O emissions were monitored during periods of 30–1070 days in treatments, which received OM inputs, alone or in combination with mineral N fertiliser; and in controls fertilised with mineral N. The overall effect of OM inputs had a slight tendency to reduce N2O emissions by 10% (n = 53). With the increasing carbon-to-nitrogen ratio of the OM inputs, this mitigation effect became more pronounced. In particular, compost and biochar significantly reduced N2O emissions by 25% (n = 6) and 33% (n = 8) respectively. However, their effect strongly depended on pedoclimatic characteristics. Regarding the other types of OM inputs studied, a slight N2O emission reduction can be achieved by their application alone, without mineral N fertiliser (by 16%, n = 17). In contrast, their co-application with mineral N fertiliser elevated emissions to some extent compared to the control (by 14%, n = 22). We conclude that amongst the seven OM inputs studied, the application of compost and biochar are the most promising soil management practices, clearly demonstrating N2O emission reduction compared to mineral N fertiliser. In contrast, other OM inputs had a small tendency to mitigate N2O emissions only when applied without mineral N fertiliser.

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Soil organic carbon (SOC) sequestration in agricultural soils is an important tool for climate change mitigation within the EU soil strategy for 2030 and can be achieved via the adoption of soil management strategies (SMS). These strategies may induce synergistic effects by simultaneously reducing greenhouse gas (GHG) emissions and/or nitrogen (N) leaching. In contrast, other SMS may stimulate emissions of GHG such as nitrous oxide (N2O) or methane (CH4), offsetting the climate change mitigation gained via SOC sequestration. Despite the importance of understanding trade-offs and synergies for selecting sustainable SMS for European agriculture, knowledge on these effects remains limited. This review synthesizes existing knowledge, identifies knowledge gaps and provides research recommendations on trade-offs and synergies between SOC sequestration or SOC accrual, non-CO2 GHG emissions and N leaching related to selected SMS. We investigated 87 peer-reviewed articles that address SMS and categorized them under tillage management, cropping systems, water management and fertilization and organic matter (OM) inputs. SMS, such as conservation tillage, adapted crop rotations, adapted water management, OM inputs by cover crops (CC), organic amendments (OA) and biochar, contribute to increase SOC stocks and reduce N leaching. Adoption of leguminous CC or specific cropping systems and adapted water management tend to create trade-offs by stimulating N2O emissions, while specific cropping systems or application of biochar can mitigate N2O emissions. The effect of crop residues on N2O emissions depends strongly on their C/N ratio. Organic agriculture and agroforestry clearly mitigate CH4 emissions but the impact of other SMS requires additional study. More experimental research is needed to study the impact of both the pedoclimatic conditions and the long-term dynamics of trade-offs and synergies. Researchers should simultaneously assess the impact of (multiple) agricultural SMS on SOC stocks, GHG emissions and N leaching. This review provides guidance to policymakers as well as a framework to design field experiments and model simulations, which can address knowledge gaps and non-intentional effects of applying agricultural SMS meant to increase SOC sequestration.

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Carbon content is a key property of soils with importance for all ecosystem functions. Measures to increase soil carbon storage are suggested with the aim to compensate for agricultural emissions. In Norway, where soils have relatively high carbon content because of the cold climate, adapting management practices that prevent the loss of carbon to the atmosphere in response to climate change is also important. This work presents an overview of the potential for carbon sequestration in Norway from a wide range of agricultural management practices and provides recommendations based on certainty in the reported potential, availability of the technology, and likelihood for implementation by farmers. In light of the high priority assigned to increased food production and degree of self-sufficiency in Norway, the following measures were considered: (1) utilization of organic resources, (2) use of biochar, (3) crop diversification and the use of cover crops, (4) use of plants with larger and deeper root systems, (5) improved management of meadows, (6) adaptive grazing of productive grasslands (7) managing grazing in extensive grasslands, (8) altered tillage practices, and (9) inversion of cultivated peat with mineral soil. From the options assessed, the use of cover crops scored well on all criteria evaluated, with a higher sequestration potential than previously estimated (0.2 Mt CO2-equivalents annually). Biochar has the largest potential in Norway (0.9 Mt CO2-equivalents annually, corresponding to 20% of Norwegian agricultural emissions and 2% of total national emissions), but its readiness level is not yet achieved despite interest from industry to apply this technology at large scale. Extensive grazing and the use of deep-rooted plants also have the potential for increasing carbon storage, but there is uncertainty regarding their implementation and the quantification of effects from adapting these measures. Based on the complexities of implementation and the expected impacts within a Norwegian context, promising options with substantial payoff are few. This work sheds light on the knowledge gaps remaining before the presented measures can be implemented.

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This paper asks whether, and if so how, it is possible to design a system characterised by coordination across sectors and levels of governance aimed at governing AMR. The ambition is, firstly, to analyse how coordination problems materialise in the governing of the AMR problem, and secondly, with an emphasis on the structure of decision-making and communication processes, to probe into how coordination of AMR governance is achieved. The paper’s focus is on Norway, which stands out as one of the better performing countries for AMR governance. Drawing on literature on coordination and governance, the paper argues that effective coordination of AMR governance is more likely to follow a ‘bottom-up’ sequencing pattern. It thus provides a study of the systems for governing AMR in a multi-level setting. Through public documents, literature and interviews with key officials involved in AMR management, the paper illustrates the importance of – and organisational barriers to – inter-sectoral cooperation and coordinated strategies and actions at different levels of governance.

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Erwinia amylovora, the causative agent of fire blight of pome fruits and other rosaceous plants belongs to the group of regulated quarantine pests. The aim of this work was to characterize the populations of E. amylovora in Norway and their geographical distribution. A total of 238 E. amylovora isolates recovered from symptomatic host plants in Norway between 1986 and 2004 were genotyped by means of a short sequence repeat (SSR) marker (ATTACAGA) on plasmid pEa29. The SSR region was amplified and amplicon size determined using fluorescent labelling and rapid, automated capillary gel electrophoresis. All isolates contained the pEa29 plasmid harbouring the investigated marker. In total, ten genotypes were identified, of which two were detected only once. The number of repeats varied from 3 to 13, with 43% of the isolates containing five repeats. Of 17 isolates collected between 1986 and 1991, all but one contained five repeats, whereas more variation was observed in isolates from the period 2000 to 2004. Most of the isolates (80%) originated from Cotoneaster bullatus, hence no relationship between genotype of the isolate and host species that it was isolated from could be detected. This historic data suggests multiple introductions of E. amylovora to Norway.

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Aim Seedling recruitment is a vital process for forest regeneration and is influenced by various factors such as stand composition, climate, and soil disturbance. We conducted a long-term field experiment (18 years) to study the effects of these factors and their interactions on seedling recruitment. Location Our study focused on five main species in boreal mixed woods of eastern Canada: trembling aspen (Populus tremuloides), paper birch (Betula papyrifera), white spruce (Picea glauca), balsam fir (Abies balsamea), and white cedar (Thuja occidentalis). Methods Sixteen 1-m2 seedling monitoring subplots were set up in each of seven stands originating from different wildfires (fire years ranging from 1760 to 1944), with a soil scarification treatment applied to every other subplot. Annual new seedling counts were related to growing-season climate (mean temperature, growing degree days and drought code), scarification, and stand effects via a Bayesian generalized linear mixed model. Results Soil scarification had a large positive effect on seedling recruitment for three species (aspen, birch and spruce). As expected, high mean temperatures during the seed production period (two years prior to seedling emergence) increased seedling recruitment for all species but aspen. Contrary to other studies, we did not find a positive effect of dry conditions during the seed production period. Furthermore, high values of growing degree days suppressed conifer seedling recruitment. Except for white cedar, basal area was weakly correlated with seedling abundance, suggesting a small number of reproductive individuals is sufficient to saturate seedling recruitment. Conclusion Our findings underscore the importance of considering multiple factors, such as soil disturbance, climate, and stand composition, as well as their effects on different life stages when developing effective forest management strategies to promote regeneration in boreal mixed-wood ecosystems.

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Hydro-pedotransfer functions (PTFs) relate easy-to-measure and readily available soil information to soil hydraulic properties (SHPs) for applications in a wide range of process-based and empirical models, thereby enabling the assessment of soil hydraulic effects on hydrological, biogeochemical, and ecological processes. At least more than 4 decades of research have been invested to derive such relationships. However, while models, methods, data storage capacity, and computational efficiency have advanced, there are fundamental concerns related to the scope and adequacy of current PTFs, particularly when applied to parameterise models used at the field scale and beyond. Most of the PTF development process has focused on refining and advancing the regression methods, while fundamental aspects have remained largely unconsidered. Most soil systems are not represented in PTFs, which have been built mostly for agricultural soils in temperate climates. Thus, existing PTFs largely ignore how parent material, vegetation, land use, and climate affect processes that shape SHPs. The PTFs used to parameterise the Richards–Richardson equation are mostly limited to predicting parameters of the van Genuchten–Mualem soil hydraulic functions, despite sufficient evidence demonstrating their shortcomings. Another fundamental issue relates to the diverging scales of derivation and application, whereby PTFs are derived based on laboratory measurements while often being applied at the field to regional scales. Scaling, modulation, and constraining strategies exist to alleviate some of these shortcomings in the mismatch between scales. These aspects are addressed here in a joint effort by the members of the International Soil Modelling Consortium (ISMC) Pedotransfer Functions Working Group with the aim of systematising PTF research and providing a roadmap guiding both PTF development and use. We close with a 10-point catalogue for funders and researchers to guide review processes and research.

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Reindeer in the Arctic seasonally suppress daily circadian patterns of behavior present in most animals. In humans and mice, even when all daily behavioral and environmental influences are artificially suppressed, robust endogenous rhythms of metabolism governed by the circadian clock persist and are essential to health. Disrupted rhythms foster metabolic disorders and weight gain. To understand circadian metabolic organization in reindeer, we performed behavioral measurements and untargeted metabolomics from blood plasma samples taken from Eurasian tundra reindeer (Rangifer tarandus tarandus) across 24 h at 2-h intervals in four seasons. Our study confirmed the absence of circadian rhythms of behavior under constant darkness in the Arctic winter and constant daylight in the Arctic summer, as reported by others.1 We detected and measured the intensity of 893 metabolic features in all plasma samples using untargeted ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS). A core group of metabolites (66/893 metabolic features) consistently displayed 24-h rhythmicity. Most metabolites displayed a robust 24-h rhythm in winter and spring but were arrhythmic in summer and fall. Half of all measured metabolites displayed ultradian sleep-wake dependence in summer. Irrespective of the arrhythmic behavior, metabolism is rhythmic (24 h) in seasons of low food availability, potentially favoring energy efficiency. In seasons of food abundance, 24-h rhythmicity in metabolism is drastically reduced, again irrespective of behavioral rhythms, potentially fostering weight gain.

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Biomethanation represents a promising approach for biomethane production, with biofilm-based processes like trickle bed reactors (TBRs) being among the most efficient solutions. However, maintaining stable performance can be challenging, and both pure and mixed culture approaches have been applied to address this. In this study, inocula enriched with hydrogenotrophic methanogens were introduced to to TBRs as bioaugmentation strategy to assess their impacts on the process performance and microbial community dynamics. Metagenomic analysis revealed a metagenome-assembled genome belonging to the hydrogenotrophic genus Methanobacterium, which became dominant during enrichment and successfully colonized the TBR biofilm after bioaugmentation. The TBRs achieved a biogas production with > 96 % methane. The bioaugmented reactor consumed additional H2. This may be due to microbial species utilizing CO2 and H2 via various CO2 reduction pathways. Overall, implementing bioaugmentation in TBRs showed potential for establishing targeted species, although challenges remain in managing H2 consumption and optimizing microbial interactions.

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Six cattle breeds native to Norway, have for almost half a century been at risk of extinction. Due to their small population sizes, they have hardly been improved by breeding for many decades. Still, the endangered breeds represent a source of genetic diversity with special milk qualities compared to the modern breed, Norwegian red (NRF). This study reports for the first time a detailed overview of their milk composition. Milk from seven native breeds, in total 200 individuals, were included in the study. Rare genetic variants of αs1-and αs2-casein, and β-casein A1 and κ-casein B were more prevalent in milk form the endangered breeds compared to NRF. Moreover, milk from these six breeds showed better renneting properties and lower incidences of non-coagulating milk, compared to the NRF milk, which showed better acid coagulation properties. This study shows the potential for native breeds in small-scale production of high-quality rennet cheeses.

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Black Soldier Fly (Hermetia illucens [L.], Diptera: Stratiomyidae) larvae (BSFL) production from food waste is gaining interest. Food waste, a heterogeneous mix of agro-food and catering leftovers serves as a challenging feedstock for BSF growth due to its varying nutrient composition. BSF, are classified as polyphagous insects with a digestive system featuring midgut for digestion and nutrient absorption. The conversion of food waste by BSFL is heavily influenced by Enterococcus, Klebsiella, Morganella, Providencia, and Scrofimicrobium, which play a vital role in substrate utilization. These microbes determine growth patterns, longevity, oviposition, and egg hatchability, which are intricately tied to the sugar and protein content of their dietary substrates. Pre-treatment techniques including hydrothermal treatment, ionization, pulse electric field discharge, and microbial treatment showed better efficiency in improving the wet waste biomass surface area and waste recovery ratio. In terms of environmental sustainability, a life cycle assessment (LCA) of food waste to BSF conversion facility yields a low global warming potential (GWP) score of 17.36 kg CO2 per ton of functional unit with a significant environmental impact during pre-treatment of food waste at a mass-rearing of BSFL. Therefore, this review emphasizes the digestive system, and gut microbiota of BSFL, with food waste-nutrient utilization by the BSFL. Environmentally promising steps involved in the valorization of food waste resources were evaluated in detail. This review also covers the international regulations involved in food waste fed BSFL, and techno-economic assessment to optimize its valuable nutrients for the new economy in waste management with less environmental footprint.

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Grazing by wildlife on agricultural land is widespread across geographical regions, and can cause human–wildlife conflicts due to reduced crop yield when the grazing pressure is high. Growing red deer (Cervus elaphus) populations in Europe call for an increased understanding of their grazing patterns to mitigate damages. We quantified how red deer grazing pressure (grazing presence and grazing level) on agricultural grass meadows (n = 60) in Norway varied across multiple spatial scales. We used a nested, hierarchical study design transcending from a broad scale (meadows across the landscape) to intermediate (between nearby meadows) and local (within-meadow) scales, allowing us to identify at which scale the variation in grazing pressure was strongest. We estimated how grazing was determined by broad-scale factors influencing forage availability and quality through population density, distance to coastline, and differences between the first versus second harvest, by intermediate-scale factors in terms of meadow management causing differences in botanical composition and quality, and by local-scale factors in terms of perceived predation risk and disturbance. At a broad scale, higher population densities were associated with higher grazing pressure, and more grazing occurred before the first compared to the second harvest. Intermediate-scale factors explained the most variation of grazing pressure from red deer, with higher grazing pressure on newly renewed meadows compared to other nearby meadows. On a local scale, more grazing occurred closer to the forest edge, providing cover, and further away from infrastructure, with increased risk and disturbance. Overall, our study highlights how drivers of grazing pressure on agricultural land vary across spatial scales. Population reductions on a broader scale may have some effect in reducing the grazing pressure, but renewed meadows will nevertheless attract red deer, causing higher grazing pressure compared to neighbouring meadows. This insight is crucial for determining effective mitigation strategies facing rising red deer populations across Europe.

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Seasonal pollen allergy is a major public health concern, with many different pollen aeroallergens being present in the atmosphere at varying levels during the season. In Norway, information about spatiotemporal variation of pollen aeroallergens is currently lacking, leading to reduced ability to manage and treat seasonal allergies. Seven pollen aeroallergens (alder, hazel, willow, birch, pine, grass and mugwort) were monitored daily for 16 years from 12 regions and coalesced to create regional pollen calendars. Seasonal statistics, such as seasonal pollen integral (SPIn), onset, duration and periods of high and very high concentrations, were calculated for all pollen types and regions. High days were further modelled with SPIn in a linear regression framework to investigate the connection between the strength of the season and number of days above high pollen thresholds. The tree pollen season occurred between January and mid-July, with the pollen aeroallergens birch and pine being the most prominent in all regions. The herb pollen season was observed to occur between June and mid-August, although mugwort was almost completely absent. The grass pollen season was mostly mild on average but more severe in some regions, primarily Kristiansand. South-east regions of Oslo, Kristiansand and Lillehammer had the overall highest pollen load, while northern regions of Bodø, Tromsø and Kirkenes had the overall lowest pollen loads. SPIn and days above high pollen thresholds had positive highly significant relationships (R2 > 0.85) for all pollen types, bar mugwort. Regional pollen calendars and seasonal statistics contribute to reliable information that can be used by medical professionals to effectively and timely manage and treat seasonal pollen allergies in Norway. Further research is needed to determine sensitization profiles of pine and willow.

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Context In high-latitude regions, variable weather conditions during the growing season and in winter cause considerable variation in forage grass productivity. Tools for predicting grassland status and yield, such as field measurements, satellite image analysis and process-based simulation models, can be combined in decision support for grassland management. Here, we calibrated and validated the BASic GRAssland (BASGRA) model against dry matter and Leaf area index data from temporary grasslands in northern Norway. Objective The objective of this study was to compare the performance of model versions calibrated against i) only region-specific ground data, ii) both region-specific ground and Sentinel-2 satellite data and, iii) field trial data from other regions. Methods Ground and satellite sensed data including biomass dry matter, leaf area index, and autumn and spring ground cover from 2020 to 2022 were acquired from 13 non-permanent grassland fields at four locations. These data were input to BASGRA calibrations together with soil and daily weather data, and information about cutting and nitrogen fertilizer application regimes. The effect of the winter season was taken into account in simulations by initiating the simulations either in autumn or in early spring. Results Within datasets, initiating the model in spring resulted in higher dry matter prediction accuracy (normalised RMSE 22.3–54.0 %) than initiating the model in autumn (normalised RMSE 41.1–93.4 %). Regional specific calibrations resulted in more accurate biomass predictions than calibrations from other regions while using satellite sensing data in addition to ground data resulted in only minor changes in biomass prediction accuracy. Conclusion All regional calibrations against data from northern Norway changed model parameter values and improved dry matter prediction accuracy compared with the reference calibration parameter values. Including satellite-sensed data in addition to ground data in calibrations did not further increase prediction accuracy compared with using only ground data. Implications Our findings show that regional data from farmers’ fields can substantially improve the performance of the BASGRA model compared to using controlled field trial data from other regions. This emphasises the need to account for regional diversity in non-permanent grassland when estimating grassland production potential and stress impact across geographic regions. Further use of satellite data in grassland model calibrations would probably benefit from more detailed assessments of the effect of grass growth characteristics and light and cloud conditions on estimates of grassland leaf area index and biomass from remote sensing.

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Context Traditional critical nitrogen (N) dilution curve (CNDC) construction for N nutrition index (NNI) determination has limitations for in-season crop N diagnosis and recommendation under diverse on-farm conditions. Objectives This study was conducted to (i) develop a new rice (Oryza sativa L.) critical N concentration (Nc) determination approach using vegetation index-based CNDCs; and (ii) develop an N recommendation strategy with this new Nc determination approach and evaluate its reliability and practicality. Methods Five years of plot and on-farm experiments involving three japonica rice varieties were conducted at fourteen sites in Qixing Farm, Northeast China. Two machine learning (ML) methods, random forest (RF) and extended gradient boosting (XGBoost) regression, were used to fuse multi-source data including genotype, environment, management, growth stage, normalized difference vegetation index (NDVI) and normalized difference red edge (NDRE) from portable active canopy sensor RapidSCAN. The CNDC was established using NDVI and NDRE instead of aboveground biomass (AGB) measured by destructive sampling. A new in-season N diagnosis and recommendation strategy was further developed using direct and indirect NNI prediction using multi-source data fusion and ML models. Results The new CNDC based on NDVI or NDRE explained 94−96 % of Nc variability in the evaluation dataset when it was coupled with environmental and agronomic factors using ML models. The ML-based PNC and NNI prediction models explained 85 % and 21–36 % more variability over simple regression models using NDVI or NDRE in the evaluation dataset, respectively. The new in-season N diagnosis strategy using the NDVI and NDRE-based CNDCs and plant N concentration (PNC) predicted with RF model and multi-source data fusion performed slightly better than direct NNI prediction, explaining 7 % more of NNI variability and achieving 89 % of the areal agreement for N diagnosis across all evaluation experiments. Integrating this new N management strategy into the precision rice management system (as ML_PRM) increased yield, N use efficiency (NUE) and economic benefits over farmer’s practice (FP) by 7–15 %, 11–71 % and 4–16 % (161–596 $ ha−1), respectively, and increased NUE by 11–26 % and economic benefits by 8–97 $ ha−1 than regional optimum rice management (RORM) under rice N surplus status under on-farm conditions. Conclusions In-season rice N status diagnosis can be improved using NDVI- and NDRE-based CNDC and PNC predicted by ML modeling with multi-source data fusion. Implications The active canopy sensor- and ML-based in-season N diagnosis and management strategy is more practical for applications under diverse on-farm conditions and has the potential to improve rice yield and ecological and economic benefits.

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Livestock summer grazing in mountains and forests in Norway is generally considered beneficial to biodiversity. In this study we investigated if this is the case for cattle in boreal production forest. We collected biodiversity data on field layer vegetation, floral resources and flower-visiting insects in young spruce plantations that were planted 2–10 years ago. We picked young spruce plantations inside and outside well-established cattle grazing areas. On each plantation, we sampled fenced and unfenced plots (20 * 20 m each). This study design allowed us to investigate long-term effects of cattle grazing as well as short-term effects of excluding cervids only and short-term effects of excluding cervids and cattle. Long-term cattle grazing reduced the abundance of woody plants and reduced the abundance of flowers. Excluding cervids for two summers led to reduced height of woody plants (shrubs and heather) and to increased flower abundance. In contrast, excluding cervids and cattle for two summers led to increased height of graminoids, herbs and woody plants, to higher abundance of graminoids, higher flower abundance and higher abundance of flower-visiting insects. In conclusion, cattle affected the studied system in different ways and to a larger extent than native cervids. Our study shows that we must be careful when inferring results from cattle grazing studies on grasslands to forest ecosystems. As this study documents a negative effect of cattle on floral resources and flower-visiting insects, and we currently are facing a global pollination crisis, a careful consideration of the current practice of cattle grazing in boreal forest might be needed.

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Climate change and human activities have accelerated the spread of non-native species, including forest pests and pathogens, significantly contributing to global biodiversity loss. Pathogens pose a significant threat to forest ecosystems due to a lack of coevolution with native hosts, resulting in ineffective defence mechanisms and severe consequences for the affected tree species. Ash dieback, caused by the fungus Hymenoscyphus fraxineus, is a relatively new invasive forest pathogen threatening ash (Fraxinus excelsior) with mortality rates in northern Europe reaching up to 80 %. The loss of ash due to dieback has severe ecological implications, potentially leading to an extinction cascade as ash provides crucial habitats and resources for many organisms. Despite this, the consequences of ash dieback on associated communities are largely unknown. To address this, we analysed changes in species richness, vegetation structure, and composition in 82 permanent vegetation plots across 23 Norwegian woodlands. We compared data collected before and 10–14 years after the emergence of ash dieback. In these woodlands, ash significantly declined in cover, leading to changes in tree species composition and facilitating the establishment of other woody tree species like hazel (Corylus avellana) and the invasive species sycamore (Acer pseudoplatanus). Despite these changes in the tree species composition, no significant alterations were observed in the understory plant community, indicating a degree of ecosystem resilience or a lagging community response. At this point, and with our focus on the vascular plants, we do not find support for cascading effects due to ash dieback. However, our findings demonstrate that one invasive species is facilitating the expansion of another, raising concerns about potential ecological imbalance and cascading effects in the future.

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Soils are the third largest carbon pool on Earth and play a crucial role in mitigating climate change. Therefore, understanding and predicting soil carbon sequestration is of major interest to mitigate climate change globally, especially in countries with strong agricultural backgrounds. In this study, we used a new database composed of 5029 samples collected up to 1-meter depth in three biomes that are most representative of agriculture, Pampas (Prairie), Cerrados (Savanna), and Atlantic Forest (Forest), to explore soil organic carbon (SOC) stocks and its environmental drivers. The Cerrado (Savanna) biome was the only one where croplands presented higher SOC stocks than native vegetation (Native vegetation 121.23 Mg/ha and croplands 127.85 Mg/ha or 5 % higher). From the tested models, the Random Forest outperformed the others, achieving an R2 of 0.64 for croplands and 0.56 for native vegetation. The accuracy of the models varied with soil depth, showing better predictions in shallow layers for croplands and deeper layers for native vegetation. Our results highlight the importance of clay content, precipitation, net primary production (NPP), and temperature as key predictors for soil carbon stocks in the studied biomes. The findings emphasize the importance of protecting the surface layers, especially in the Cerrado biome, to enhance SOC stocks and promote sustainable land management practices. Moreover, the results provide valuable insights for the development of nature-based carbon markets and suggest potential strategies for climate change mitigation. Enhancing our understanding of SOC dynamics and adopting precise environmental predictors will contribute to the formulation of targeted soil management strategies and accelerate progress toward achieving climate goals.

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Mountain areas in Norway provide important resources for livestock grazing. These resources are crucial for agricultural production in a country with limited agricultural land and a climate and topography that restrict production of feed and food. A key contributor in the harvest of these resources has been mountain summer farming and outfield grazing in general. However, the use of mountainous grazing resources has been declining strongly for several decades with the regrowth of formerly open areas as a consequence. In contrast, recreational use, number of holiday cabins and associated infrastructure is rapidly increasing. Conflicts between recreational and agriculture use have received increasing attention in different media. We investigated the spatial patterns of cabin development and key grazing areas in Norwegian mountain areas, analysing data on livestock, cabins, and associated infrastructure. We found a large number of cabins and associated infrastructure within high-quality grazing areas indicating that the quality of grazing has not been adequately considered in the location of new cabins. Taking into consideration that cabin development seems not to decrease, the reduced availability of grazing resources may result in an increasing level of conflict and also impact food security in the long run.

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CONTEXT European dairy cattle production systems (DPS) are facing multiple challenges that threaten their social, economic, and environmental sustainability. In this context, it is crucial to implement options to promote the reconnection between crop and livestock systems as a way to reduce emissions and enhance nutrient circularity. However, given the sector's diversity, the successful implementation of these options lacks an evaluation framework that jointly considers the climatic conditions, farm characteristics, manure management and mineral fertilisation practices of DPS across Europe. OBJECTIVE This study aims to develop a modelling and statistical framework to assess the effect of climatic conditions, farm characteristics, manure management and mineral fertilisation practices on the on-farm sources of greenhouse gas (GHG) emissions and nitrogen (N) losses from ten contrasting case studies for dairy production across Europe, identifying options for emissions mitigation and nutrient circularity. METHODS Using the SIMSDAIRY deterministic whole-farm modelling approach, we estimated the GHG emissions and N losses from the ten case studies. SIMSDAIRY captures the effect of different farm management choices and site-specific conditions on nutrient cycling and emissions from different components of a dairy farm. In addition, we applied the Factor Analysis for Mixed Data multivariate statistical approach to quantitative and qualitative variables and identified relationships among emissions, nutrient losses, and the particular characteristics of the case studies assessed. RESULTS AND CONCLUSIONS The results showed how intensive case study farms in temperate climates were associated with lower enteric emissions but higher emissions from manure management (e.g. housing). In contrast, semi-extensive case study farms in cooler climates exhibited higher N losses and GHG emissions, directly linked to increased mineral fertilisation, excreta during grazing, and slurry application using broadcast. Furthermore, the results indicated opportunities to improve nutrient circularity and crop-livestock integration by including high-quality forages instead of concentrates and substituting mineral fertilisers with organic fertilisers. SIGNIFICANCE The presented framework provides valuable insights for designing, implementing, and monitoring context-specific emission mitigation options and nutrient circularity practices. By combining whole-farm modelling approaches and multivariate statistical methods, we enhance the understanding of the interactions between sources of N losses and GHG emissions. We expect our findings to inform the adoption of emissions reduction and circularity practices by fostering the recoupling between crop and livestock systems.

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CONTEXT Researchers have identified numerous strategies to improve economic performance and reduce greenhouse gas (GHG) emission intensity in combined milk and beef production on dairy farms. However, there remains a need to better understand how the effectiveness of these strategies varies under different operational conditions. OBJECTIVE This study aims to examine how the economic and GHG emission intensity mitigation effectiveness of increased milk yield, extended longevity of dairy cows, reduced age at first calving, and intensified beef production from bulls depend on operational conditions in dual purpose cattle systems. METHOD We present a quantitative framework to (1) economically optimize production at farm level under various constraints and (2) calculate corresponding GHG emissions. The framework is tailored for Norwegian dual-purpose cattle systems and used to assess the economic and GHG emission intensity mitigation effects of incremental adjustments in relevant decisions. RESULTS AND CONCLUSIONS The results show that increased milk yield, extended productive life of dairy cows, reduced age at first calving, and lower slaughter age of bulls can lead to economic and climatic win-wins in terms of higher gross margins and reduced emissions per kg of protein produced. However, they may also result in lose-win and win-lose outcomes depending on the operational conditions. All four measures free up roughage production capacity, which, if used to maintain/increase milk and/or beef production, typically results in economic gains. However, if e.g., the available milk quota or space prevent this, economic losses may occur. The climate impact also depends on how the freed-up capacity is used: if it boosts production, the effects vary based on the scale and type of increase and the farm's initial setup, while unused capacity leads to reduced emission intensity. Conflicts typically arise when: 1) the extra capacity increases less climate-friendly production, raising emission intensity despite economic gains, or 2) extra capacity cannot be used, causing economic losses despite climate benefits. Our results also show that what can be labeled a win in climate terms, and to what extent, depends on the selected target metric(s). SIGNIFICANCE Governments and societies strive to balance food production with environmental goals. In this context, it is essential to identify farm-level economic and climatic win-win and lose-win scenarios, not only for farmers but also for policymakers and the broader society. This study could inform decision-making and policy development, potentially enhancing economic and climatic performance in combined milk and meat production.

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CONTEXT An important question for farmers is whether to run their farm conventionally or organically. This choice can significantly affect the farm's financial performance and its impact on the environment. OBJECTIVE The primary objective of this study is to compare the profitability of conventional and organic cattle systems and investigate how it is associated with individual farm characteristics, like forage production capacity, forage quality, milk quota, animal housing capacity, and their relative presences. METHOD We employ a whole farm optimization model, customized for Norwegian cattle farming. The primary goal of this model is to maximize the gross margin by optimizing decisions related to land usage and animal inventory while adhering to a set of constraints. We systematically solve more than 200,000 model instances, with varying farm characteristics. RESULTS AND CONCLUSIONS The results can be distilled to the following key points: If forage of good quality is readily available, but the livestock operation cannot be expanded due to animal housing and milk quota restrictions, organic may outcompete conventional farming. Otherwise, gross margin is maximized with conventional farming. These findings emphasize the crucial role of forage production capacity and quality in relation to available milk quota and infrastructure when considering the transition from conventional to organic farming. Extensive sensitivity analyses affirm the robustness of these conclusions. Regional regulatory factors, such as government farm payments, also play a significant role, and influence the optimal farming approach. Additionally, we show that increases in organic price premiums can markedly impact the competitiveness of organic farming, even in a system where government payments make out a significant part of the farm revenue. SIGNIFICANCE The model can support farmers to make informed decisions about converting to organic or conventional farming. It can also be used by policymakers to determine the level of support required to make it worthwhile for different types of farms to convert. We also show that existing government payment schemes give rise to regional differences in the incentives for organic farming in Norway. To ensure equal incentives for organic farming across the country, the organic payments would have to be regionally adjusted, in line with the other already regionally dependent government payments. This insight may be of significant interest to policymakers and other stakeholders.

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We address the question of nature-culture synergies in protected mountain landscapes with a specific focus on the Norwegian National Park of Hardangervidda. Fragile and complex ecosystems developed from long-lasting socio-ecological grazing processes that started approximately 4000 years ago in Scandinavia are facing manifold environmental challenges and societal issues that endanger both natural and cultural heritages. Our goals are to clarify the nature-culture synergies and relationships and investigate holistic management and preservation of natural and cultural values. Our results highlight an urgent need to develop holistic conservation frameworks and methodologies for protected landscapes that integrate cultural and natural heritages and enhance the potential of local communities to protect threatened semi-natural environments and experienced-based knowledge for the future.

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The fall armyworm, Spodoptera frugiperda, situation in Africa remains a priority threat despite significant efforts made since the first outbreaks in 2016 to control the pest and thereby reduce yield losses. Field surveys in Benin and Mali reported that approximately one-week post-emergence of maize plants, the presence of fall armyworm (egg/neonates) could be observed in the field. Scouting for fall armyworm eggs and neonates is, however, difficult and time consuming. In this study, we therefore hypothesized that the optimum timeframe for the fall armyworm female arriving to lay eggs in sown maize fields could be predicted. We did this by back-calculating from interval censored data of egg and neonates collected in emerging maize seedlings at young leaf developmental stage. Early time of ovipositing fall armyworm after sowing was recorded in field experiments. By using temperature-based models to predict phenological development for maize and fall armyworm, combined with analytical approaches for time-to-event data with censored status, we estimated that about 210 accumulated Degree Days (DD) is needed for early detection of neonate larvae in the field. This work is meant to provide new insights on timely pest detection and to guide for precise timing of control measures.

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Botrytis blossom blight disease is one of the major challenges to wild blueberry production with annual losses frequently exceeding 20%. In this study, the effect of different fungicide treatments on Botrytis blight development and yield, as well as the mobility and persistence of these fungicides within flower tissues, and fruit of wild blueberries were evaluated under field conditions. This multi-year trial examined five different fungicides (Switch®, Luna Tranquility®, Merivon® Xenium, Propulse®, and Miravis® Prime) each one applied twice at 7-10-day interval. Fungicide quantification in the floral and berry tissues was conducted using a modification of the QuEChErs extraction method and analyzed with GC-MS and HPLC-MS. All the treatments except Switch® reduced disease incidence by over 78 % and severity by over 40 %, compared to the control plots. Switch® and Miravis® Prime reduced both incidence and severity by over 64 % compared to the control plots. Luna Tranquility®, Merivon® Xenium, and Propulse® reduced incidence by at least 47 % and severity by 51 % compared to the control plots. Berry yields were higher in Switch®, Luna Tranquility® and Miravis® Prime treated plots with at least a 19% increase in yield compared to the control plots. The mean concentration of all quantified fungicides was higher in the corolla compared to the gynoecium and the androecium sample areas. Fungicides were persistent and concentrations were sufficient to suppress Botrytis cinerea at fruit set (10 days post application) with no residue detected in harvested berries, except prothioconazole-desthio.

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Gray mold, caused by Botrytis spp., is a serious problem in Norway spruce seedling production in forest nurseries. From 2013 to 2019, 125 isolates of Botrytis were obtained from eight forest nurseries in Norway: 53 from Norway spruce seedlings, 16 from indoor air, 52 from indoor surfaces, and four from weeds growing close to seedlings. The majority of isolates were identified as B. cinerea, and over 60% of these were characterized as Botrytis group S. B. pseudocinerea isolates were obtained along with isolates with DNA sequence similarities to B. prunorum. Fungicide resistance was assessed with a mycelial growth assay, and resistance was found for the following: boscalid (8.8%), fenhexamid (33.6%), fludioxonil (17.6%), pyraclostrobin (36.0%), pyrimethanil (13.6%), and thiophanate-methyl (50.4%). Many isolates (38.4%) were resistant to two to six different fungicides. A selection of isolates was analyzed for the presence of known resistance-conferring mutations in the cytb, erg27, mrr1, sdhB, and tubA genes, and mutations leading to G143A, F412S, ΔL497, H272R, and E198A/F200Y were detected, respectively. Detection of fungicide resistance in Botrytis from Norway spruce and forest nursery facilities reinforces the necessity of employing resistance management strategies to improve control and delay development of fungicide resistance in the gray mold pathogens.

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Extended Multiplicative Signal Correction (EMSC) is a multivariate linear modelling technique for multi-channel measurements that can identify and correct for different types of systematic variation patterns, known or unknown. It is typically used for pre-processing to separate light absorbance spectra, obtained by diffuse reflectance of intact samples, into three main sources of variation: additive variations due to chemical composition (≈Beer's law), mixed multiplicative and additive variations due to physical light scattering (≈Lambert's law) and more or less random measurement noise. The present work evaluates the use of EMSC to pre-process near infrared spectra obtained by hyperspectral imaging of Scots pine sapwood, inoculated with two different basidiomycete fungi and at various degradation stages. The spectral changes due to fungal decay and resulting mass loss are assessed by interpretation of the EMSC parameters and the partial least squares regression (PLSR) results. Including a cellulose (analyte) or bound water (interferent) spectral profile in the EMSC pre-processing model generally improves the predictive performance of the PLS modelling, but it can also make it worse. The inclusion of the additional polynomial baselines does not necessarily lead to a better separation of the physical and chemical effects present in the spectra. The estimated EMSC parameters provide insight into the differences in decay mechanisms. A detailed analysis of the EMSC results highlights advantages and disadvantages of using a complex pre-processing model.

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Climate change is and will continue to alter plant responses to their environment. This is especially prominent concerning the adaptive tracking in reproductive phenology. For wind pollinated plants, this will substantially influence their pollen seasonality, yet there are gaps in knowledge about how environmental variation influences pollen seasonality. To investigate this, we monitored daily atmospheric pollen concentrations of seven pollen types from ecologically, economically and allergenically important plants (alder, hazel, willow, birch, pine, grass and mugwort) in twelve Norwegian locations spanning the entire country for up to 28 years. Six daily meteorological variables (maximum temperature, precipitation, wind speed, relative humidity, solar radiation and atmospheric pressure) was obtained from the MET Nordic dataset with full data cover. The pollen seasonality was then modelled using four spatial, three temporal and the six meteorological variables in a generalized linear model approach with a negative binomial distribution to investigate how each variable group thematically and individually contribute to variation in pollen seasonality. We found that the full models explained the most variation, ranging from R2 = 20.3 % to 59.5 %. The models were also highly accurate, being able to predict 54.5 % to 99.1 % of daily pollen concentrations to within 20.1 pollen grains/m3. Overall, the temporal variables were able to explain more variation than spatial and meteorological variables for most pollen types. Month, altitude and maximum temperature were the most important single variables for each category. The importance of each variable could be traced back to their individual effects of reproductive phenology, plant metabolism, species distributions and pollen release processes. We further emphasise the importance of source maps and atmospheric regional transport models in further model improvements. By understanding the relevance of environmental variation to pollen seasonality we can make better predictions regarding the consequences of climate change on plant populations.

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Monitoring surface albedo at a fine spatial resolution in forests can enrich process understanding and benefit ecosystem modeling and climate-oriented forest management. Direct estimation of surface albedo using 10 m reflectance imagery from Sentinel-2 is a promising research avenue to this extent, although questions remain regarding the representativeness of the underlying model of surface reflectance anisotropy originating from coarser-resolution imagery (e.g., MODIS). Here, using Fennoscandia (Norway, Sweden, Finland) as a case region, we test the hypothesis that systematic stratification of the forested landscape into similar species compositions and physical structures prior to the step of carrying out angular bin regressions can lead to improved albedo estimation accuracy of direct estimation algorithms. We find that such stratification does not lead to statistically meaningful improvement over stratification based on conventional land cover classification, suggesting that factors other than forest structure (e.g., soils, understory vegetation) may be equally important in explaining within-forest variations in surface reflectance anisotropy. Nevertheless, for Sentinel-2-based direct estimation based on conventional forest classification, we document total-sky surface albedo errors (RMSE) during snow-free and snow-covered conditions of 0.015 (15 %) and 0.037 (21 %), respectively, which align with those of the coarser spatial resolution products in current operation.

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The presence of viral diseases poses a significant challenge to the high-quality, efficient, and sustainable production of apples. Virus eradication and the use of virus-free plants are currently the most crucial method for preventing viral diseases. Among the viruses affecting apples, apple stem grooving virus (ASGV) and apple chlorotic leaf spot virus (ACLSV) present particular challenges in efficient eradication from apples. This study investigated the effects of exogenous salicylic acid (SA) treatment on the efficient eradication of ASGV and ACLSV from apple cultivar ‘Yanfu 8’. Shoots were excised from in vitro 4-week-old stock and cultured in shoot proliferation medium supplemented with 10 μM SA combining thermotherapy with shoot tip culture or cryotherapy for ASGV and ACLSV eradication. The results showed that including of 10 μM SA in thermotherapy significantly reduced the concentrations of ASGV and ACLSV by 33% and 14% in shoots compared to thermotherapy without SA. SA treatment also improved the shoot tips survival and regrowth after combining 2 or 4 weeks of thermotherapy followed by shoot tip culture or shoot tip cryotherapy, while maintaining the higher (75–100%) of virus eradication efficiencies. Therefore, the application of SA in combination with thermotherapy followed or not by cryotherapy proves to be a promising approach for enhancing the efficiency of virus eradication in apple.

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Potato is an important part of the traditional Norwegian diet, and the crop faces several challenges with respect to pests and diseases, as well as the increasingly challenging changes in climate. Genome editing may provide tools to improve the resilience of Norwegian potato cultivars to new climate challenges. We have altered the skin colour of two potato cultivars, ‘Desirée’ and ‘Nansen’ from red to yellow, as a proof-of-concept for the use of CRISPR/Cas9 in a Norwegian cultivar. Our method has involved the use of protoplasts and we have grown the regenerants for three successive clonal tuber generations to evaluate the stability of the edited plants over time and under varying temperature conditions in contained rooms in a greenhouse. We found that the protoplast method is well suited to achieving CRISPR/Cas9 applications. The results show that the yellow skin is consistent over the three generations of tuber propagation. We found some suspected somaclonal variation in the protoplast regenerants. Some of the variation which we observed under high temperatures (up to nearly 40ºC) during the second growth cycle, disappeared when cultivated under lower temperatures in the third cultivation cycle.

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Precompression stress, compression index, and swelling index are used for characterizing the compressive behavior of soils, and are essential soil properties for establishing decision support tools to reduce the risk of soil compaction. Because measurements are time-consuming, soil compressive properties are often derived through pedotransfer functions. This study aimed to develop a comprehensive database of soil compressive properties with additional information on basic soil properties, site characteristics, and methodological aspects sourced from peer-reviewed literature, and to develop random forest models for predicting precompression stress using various subsets of the database. Our analysis illustrates that soil compressive properties data primarily originate from a limited number of countries. There is a predominance of precompression stress data, while little data on compression index or recompression index are available. Most precompression stress data were derived from the topsoils of conventionally tilled arable fields, which is not compatible with knowledge that subsoil compaction is a serious problem. The data compilation unveiled considerable variations in soil compression test procedures and methods for calculating precompression stress across different studies, and a concentration of data at soil moisture conditions at or above field capacity. The random forest models exhibited unsatisfactory predictive performance although they performed better than previously developed models. Models showed slight improvement in predictive power when the underlying data were restricted to a specific precompression stress calculation method. Although our database offers broader coverage of precompression stress data than previous studies, the lack of standardization in methodological procedures complicates the development of predictive models based on combined datasets. Methodological standardization and/or functions to translate results between methodologies are needed to ensure consistency and enable data comparison, to develop robust models for precompression stress predictions. Moreover, data across a wider range of soil moisture conditions are needed to characterize soil mechanical properties as a function of soil moisture, similar to soil hydraulic functions, and to develop models to predict the parameters of such soil mechanical functions.

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Land management systems that comprise the principles of conservation agriculture (CA) can lead to soil organic carbon (SOC) gains over time. Nonetheless, how fertilization regimes interfere with their performance in highly weathered soils is still uncertain. This study presents results on SOC storage, crop yield, and soil resilience from a long-term experiment in southern Brazil (Ponta Grossa – Paraná State) 26 years after its establishment in 1989 combining a gradient of soil disturbance through diverse soil management strategies with contrasting fertilization regimes. We hypothesized that preserving soil structure rebuilt over time through no-till system plays a significant role in SOC persistence and the fertilization regime can impact land management performance on soil resilience and crop yield. The experimental design was laid out as a split plot through completely randomized blocks. The main plots comprised the treatments related to soil management systems: 1) conventional plow-based tillage – CT; 2) minimum tillage (Chiselling replacing plowing) – MT; 3) no-till with one chisel plowing every three years – NTch; and 4) continuous no-till system – NTS. The sub-plots comprised full crop fertilization (FCF) for all crops and low crop fertilization (LCF) by suppressing K and P fertilization and maintaining N in broadcast application. SOC stocks significantly improved as the soil disturbance diminished, resulting in higher soil resilience indexes for NTS and NTch. Differences in SOC stocks between the contrasting treatments NTS and CT were higher under low fertilization, resulting in C and N sequestration rates of 1.14 and 0.14 Mg ha−1 year−1 under LCF compared to 0.77 and 0.08 Mg ha−1 yr−1 in FCF at the 0–100 cm layer. Such higher differences were induced by overall higher SOC stocks of CT when under FCF and higher SOC stocks in subsoil depths promoted by NTS when under LCF. High fertilization treatments produced cumulative yields 1.5 times higher for soybeans and 2.5 times higher for corn throughout the 26 years of the experiment. Labile C fractions extracted by hot water (HWEOC) and K-permanganate (POXC) were systematically increased as the disturbance diminished. Gains in labile fractions were promoted in deeper layers in lower disturbance treatments (NTch and NTS). We conclude that combining conservation agriculture principles ultimately defined the potential for SOC sequestration. The high soil resilience under the NTS in this research indicates a considerable potential to reverse the soil degradation and decline of the SOC and labile fractions by conversion to intensive NTS (high and diversified annual C input) associated with absence of soil disturbance.

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Cellulose is a major renewable resource for a wide variety of sustainable industrial products. However, for its utilization, finding new efficient enzymes for plant cell wall depolymerization is crucial. In addition to microbial sources, cellulases also exist in plants, however, are less studied. Fleshy fruit ripening includes enzymatic cell wall hydrolysis, leading to tissue softening. Therefore, bilberry (Vaccinium myrtillus L.), which produces small fruits that undergo extensive and rapid softening, was selected to explore cellulases of plant origin. We identified 20 glycoside hydrolase family 9 (GH9) cellulases from a recently sequenced bilberry genome, including four of which showed fruit ripening-specific expression and could be associated with fruit softening based on phylogenetic, transcriptomic and gene expression analyses. These four cellulases were secreted enzymes: two B-types and two C-types with a carbohydrate binding module 49. For functional characterization, these four cellulases were expressed in Pichia pastoris. All recombinant enzymes demonstrated glucanase activity toward cellulose and hemicellulose substrates. Particularly, VmGH9C1 demonstrated high activity and ability to degrade cellulose, xyloglucan, and glucomannan. In addition, all the enzymes retained activity under wide pH (6–10) and temperature ranges (optimum 70 °C), revealing the potential applications of plant GH9 cellulases in the industrial bioprocessing of lignocellulose.

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Future agricultural practices necessitate green alternatives to replace hazardous insecticides while distinguishing between pests and beneficial insects. Chitosan, as a biological macromolecule derived from chitin, is biodegradable and exhibits low toxicity to non-target organisms, making it a sustainable alternative to synthetic pesticides. This review identifies chitosan-derivatives for insecticidal activity and highlights its efficacy including genotoxicity, defense mechanism, and disruption of insect's exoskeleton at different concentrations against several insect pests. Similarly, synergistic effects of chitosan in combination with natural extracts, essential oils, and plant-derived compounds, enhances insecticidal action against various pests was evaluated. The chitosan-based insecticide formulations (CHIF) in the form of emulsions, microcapsules, and nanoparticles showed efficient insecticide action on the targeted pests with less environmental impact. The current challenges associated with the field-trial application were also recognized, by optimizing potent CHIF-formulation parameters, scaling-up process, and regulatory hurdles addressed alongside potential solutions. These findings will provide insight into achieving the EU mission of reducing chemical pesticides by 50 %.

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Microalgae are promising production platforms for the cost-effective production of recombinant proteins. We have recently established that the red alga Porphyridium purpureum provides superior transgene expression properties, due to the episomal maintenance of transformation vectors as multicopy plasmids in the nucleus. Here, we have explored the potential of Porphyridium to synthesize complex pharmaceutical proteins to high levels. Testing expression constructs for a candidate subunit vaccine against the hepatitis C virus (HCV), we show that the soluble HCV E2 glycoprotein can be produced in transgenic algal cultures to high levels. The antigen undergoes faithful posttranslational modification by N-glycosylation and is recognized by conformationally selective antibodies, suggesting that it adopts a proper antigenic conformation in the endoplasmic reticulum of red algal cells. We also report the experimental determination of the structure of the N-glycan moiety that is attached to glycosylated proteins in Porphyridium. Finally, we demonstrate the immunogenicity of the HCV antigen produced in red algae when administered by injection as pure protein or by feeding of algal biomass.

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Biochar modification is an effective approach to enhance its ability to promote anaerobic digestion (AD). Focusing on the physical properties of biochar, the impact of different particle sizes of biochar on AD of food waste (FW) at high organic loading rate (OLR) was investigated. Four biochar with different sizes (40–200 mesh) were prepared and used in AD systems at OLR 30 g VS/L. The research results found that biochar with a volume particle size of 102 μm (RBC-P140) had top-performance in promoting cumulative methane production, increasing by 13.20% compared to the control group. The analysis results of the variety in volatile acids and alkalinity in the system did not show a correlation with the size of biochar, but small size has the potential to improve the environmental tolerance of the system to high acidity. Microbial community analysis showed that the abundance of aceticlastic methanogen and the composition of zoogloea were optimized through relatively small-sized biochar. Through revealing the effect of biochar particle size on AD system at high OLR, this work provided theoretical guidance for regulating fermentation systems using biochar.

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The uptake dynamics of two sulfonamide antibiotics, two fluoroquinolone antibiotics, and the anticonvulsant carbamazepine during the cultivation of two species of edible mushrooms (Agaricus subrufescens and A. bisporus) was investigated. None of the antibiotics were accumulated by the mushrooms, while carbamazepine and its transformation product carbamazepine-10,11-epoxide were taken up by A. bisporus fruiting body but only in small amounts (up to 0.76 and 1.85 μg kg−1 dry weight, respectively). The sulfonamides were quickly removed from the mushroom growth substrate, while the recalcitrant fluoroquinolones and carbamazepine were only partially removed. Dissipation half-lives were generally lower for A. subrufescens than A. bisporus, but A. subrufescens was also grown at a slightly higher culture temperature. A. subrufescens also showed a lower uptake of contaminants. Comparison of maximum dietary intake with other common exposure sources showed that these mushrooms can safely be eaten although produced on a polluted substrate, with respect to the investigated compounds.

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Fast regrowth from deep roots and rhizomes makes it difficult to mechanically control the perennials Cirsium arvense and Tussilago farfara respectively. It is, however, not clear whether new shoots originate mainly from fragments of roots/rhizomes in upper soil layers or from an intact system below depth of soil cultivation. Here we present results from three experiments with natural infestations of C. arvense, and two with both C. arvense and T. farfara. Plots of 1 m2 were excavated to different depths (13–25 cm), all below-ground plant parts in the topsoil were collected and thereafter fragments were either returned to or removed from the plots. Regrowth from disturbed plots with removed or returned fragments was compared. The origin of regrown shoots, that is, whether they originated from seeds, intact below-ground root/rhizome systems or returned fragments, was examined. More C. arvense shoots originated from the intact root system (48%–84%) than from root fragments (16%–52%). The final aboveground biomass was not affected by removal of the top-soil fragments. For T. farfara, a small proportion (3%) of new shoots originated from the intact rhizome system, and the rest from fragments. We conclude that the intact root system of C. arvense contributes at least as much as root fragments to regrowth after soil cultivation, which might imply that time of treatment and depth of cultivation are crucial for the effect of mechanical control. For T. farfara, the results suggest that tillage equipment with high capacity to fragment the rhizome system will contribute to efficient control.

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1. We propose that the ecological resilience of communities to permanent changes of the environment can be based on how variation in the overall abundance of individuals affects the number of species. Community sensitivity is defined as the ratio between the rate of change in the log expected number of species and the rate of change in the log expected number of individuals in the community. High community sensitivity means that small changes in the total abundance strongly impact the number of species. Community resistance is the proportional reduction in expected number of individuals that the community can sustain before expecting to lose one species. A small value of community resistance means that the community can only endure a small reduction in abundance before it is expected to lose one species. 2. Based on long-term studies of four bird communities in European deciduous forests at different latitudes large differences were found in the resilience to environmental perturbations. Estimating the variance components of the species abundance distribution revealed how different processes contributed to the community sensitivity and resistance. Species heterogeneity in the population dynamics was the largest component, but its proportion varied among communities. Species-specific response to environmental fluctuations was the second major component of the variation in abundance. 3. Estimates of community sensitivity and resistance based on data only from a single year were in general larger than those based on estimates from longer time series. Thus, our approach can provide rapid and conservative assessment of the resilience of communities to environmental changes also including only short-term data. 4. This study shows that a general ecological mechanism, caused by increased strength of density dependence due to reduction in resource availability, can provide an intuitive measure of community resilience to environmental variation. Our analyses also illustrate the importance of including specific assumptions about how different processes affect community dynamics. For example, if stochastic fluctuations in the environment affect all species in a similar way, the sensitivity and resistance of the community to environmental changes will be different from communities in which all species show independent responses.

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Forest grazing by free-roaming livestock is a common practice in many countries. The forestry sector sees the practice as unfortunate owing to several reasons, such as damages inflicted by grazing in young plantations. Concerning Norway spruce forests, a tree species known to develop wood decay with high frequency followed from stem bark damage, there is a strong perception among foresters that the trampling damage caused by livestock on the superficial root system of this tree leads to decay. Because of the very limited scientific documentation available on this topic, we pursued a clarification by investigating three 38- to 56-year-old Norway spruce forests used for silvopasture. Two types of injuries were observed on exposed roots: bark cracks characterized by resin exudation, and injuries involving localized bark peeling and exposure of the underlying wood. These injuries occurred up to 250 cm away from the root collar, with the sector 50–150 cm away from the root collar showing the highest incidence of injuries. In two of the forest stands, wood within the injured root areas was primarily colonized by the wound parasite Corinectria fuckeliana or species of the order Helotiales, fungi that do not cause wood decay. Wood colonization of injured roots by Heterobasidion species, the most frequent wood decay fungi of Norway spruce, was common in the third stand, but only in a few cases it was possible to deduce that the colonization had probably initiated via trampling injuries on roots. In a few cases, an injury was located at stem base at the root collar height along paths used by animals, and in such cases, it was obvious that stem colonization by Heterobasidion species had initiated via the wound. The relatively small amount of data warrants caution when drawing conclusions. Considering the high establishment frequency of decay via stem bark wounds of Norway spruce observed in previous studies, our data would suggest that roots are generally better equipped to defend themselves upon infliction of superficial wounds than stem of this tree species. The likelihood of trampling injuries leading to decay may vary considerably between different stands, this presumably depending on the level of local propagule pressure by pathogenic wood decay fungi and the frequency of damages close to root collar.

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Rising organic charge in northern freshwaters is attributed to increasing levels of dissolved natural organic matter (DNOM) and changes in water chemistry. Organic charge concentration may be determined through charge balance calculations (Org.−) or modelled (OAN−) using the Oliver and Hruška conceptual models, which are based on the density of weak acid functional sites (SD) present in DNOM. The charge density (CD) is governed by SD as well as protonation and complexation reactions on the functional groups. These models use SD as a key parameter to empirically fit the model to Org.−. Utilizing extensive water chemistry datasets, this study shows that spatial and temporal differences in SD and CD are influenced by variations in the humic-to-fulvic ratio of DNOM, organic aluminum (Al) complexation, and the mole fraction of CD to SD, which is governed by acidity. The median SD values obtained for 44 long-term monitored acid-sensitive lakes were 11.1 and 13.9 µEq/mg C for the Oliver and Hruška models, respectively. Over 34 years of monitoring, the CD increased by 70%, likely due to rising pH and declining Al complexation with DNOM. Present-day median SD values for the Oliver and Hruška models in 16 low-order streams are 13.8 and 15.8 µEq/mg C, respectively, and 10.8 and 12.5 µEq/mg C, respectively, in 10 high-order rivers.

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Currently used pesticides (CUPs) were introduced to have lower persistence and bioaccumulation, and lesser bioavailability towards non-target species. Nevertheless, CUPs still represent a concern for both human health and the environment. India is an important agricultural country experiencing a conversion from the use of obsolete organochlorine pesticides to a newer generation of phytosanitary products. As for other developing countries, very little is known about the transfer of CUPs to the human diet in India, where systematic monitoring is not in place. In this study, we analyzed ninety four CUPs and detected thirty CUPs in several food products belonging to five types: cereals and pulses, vegetables, fruits, animal-based foods, and water. Samples were taken from markets in Delhi (aggregating food produced all over India) and in the periurban area of Dehradun (northern India) (representing food produced locally and through more traditional practices). Overall, chlorpyrifos and chlorpropham were the most detected CUPs with a detection frequency of 33% and 25%, respectively. Except for vegetables and fruits, the levels of CUPs in all other food types were significantly higher in samples from Delhi (p < 0.05). Exposure dosage of CUPs through different food matrices was calculated, and chlorpropham detected in potatoes had the maximum exposure dosage to humans (2.46 × 10−6 mg/kg/day). Risk analysis based on the hazard quotient technique indicated that chlorpyrifos in rice (2.76 × 10−2) can be a concern.

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To better characterize properties governing the sorption of per- and polyfluoroalkyl substances (PFAS) to biochar, twenty-three diverse biochars were characterized and evaluated as sorbents for perfluorooctanoic acid (PFOA). Biochars were produced at various temperatures, using two different technologies, and made from sewage sludge, food waste reject, wood wastes, and one reference substrate (wood pellets). The biochars were characterized in terms of surface area, pore volume and pore size distributions, elemental composition, leachable elements, ash content, pH, zeta potential, condensed aromatic carbon (ConAC) content (determined by benzenepolycarboxylic acid (BPCA) markers), and their -OH functional group content (infrared spectroscopy). PFOA sorption isotherms were determined using Polanyi-Dubinin-Manes (PDM) and Freundlich models. The sludge-based biochars [Freundlich coefficients (log KF) between 2.56 ± 0.11 and 6.72 ± 0.22 (μg/kg)/(μg/L)nF; fitted free energy of adsorption (E) and pore volume (Vo) from the PDM model between 13.27 and 17.26 kJ/mol, and 0.50 and 523.51 cm3/kg] outperformed wood biochars [log KF between 1.02 and 4.56 ± 0.22 (μg/kg)/(μg/L)nF; E between 9.87 and 17.44 kJ/mol; Vo between 0.21 and 7.16 cm3/kg] as PFOA sorbents. Multivariate statistical analysis revealed that the sorption capacity was mainly controlled by pore volume within the pore diameter region that could accommodate the molecular size of PFOA (3–6 nm). Hydrophobic interactions between PFOA and aromatic carbon rich regions controlled sorption affinity, especially in the wood biochars.

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The use of bio-based composites to enhance the methane production in anaerobic digestion has attracted considerable attention. Nevertheless, the study of electron transfer mechanisms and the applications of biochar/MnO2 (MBC) in complex systems remains largely unexplored. Biochar composited with MnO2 at 10:1 mass ratio (MBC10) increased the content of volatile fatty acids by 9.09 % during acidogenic phase. During the methanogenic experiments using acetate, cumulative methane production (CMP) rose by 5.83 %, and in the methanogenic experiments using food waste, CMP increased by 24.32 %. Microbial community analysis indicated an enrichment of Syntrophomonas, Bacilli, and Methanosaetaceae in the MBC10 group. This enrichment occurred mainly due to the redox capability of MnO2 enhancing MBC capacitance, thereby facilitating microbial electron transfer processes. Additionally, under 2 g/L ammonia nitrogen concentration and 30 g/L organic load, the CMP of MBC10 increased by 12.74 % and 9.44 %, respectively, compared to the BC600 group. This study illuminates MBC's electron transfer mechanisms and applications, facilitating its wider practical adoption and fostering future innovations.

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To shift towards low-fossil carbon economies, making more out of residual biomass is increasingly promoted. Yet, it remains unclear if implementing advanced technologies to reuse these streams really achieves net environmental benefits compared to current management practices. By integrating spatially-explicit resource flow analysis, consequential life cycle assessment (LCA), and uncertainty analysis, we propose a single framework to quantify the residual biomass environmental baseline of a territory, and apply it to the case of France. The output is the environmental threshold that a future large-scale territorial bioeconomy strategy should overpass. For France, we estimate the residual biomass baseline to generate 18.4 ± 2.7 MtCO2-eq·y−1 (climate change), 255 ± 35 ktN-eq·y−1 (marine eutrophication), and 12,300 ± 800 disease incidences per year (particulate matter formation). The current use of crop residues and livestock effluents, being essentially a return to arable lands, was found to represent more than 90 % of total environmental impacts and uncertainties, uncovering a need for more certain data. At present, utilizing residual streams as organic fertilizers fulfills over half of France's total phosphorus (P) and potassium (K) demands. However, it only meets 6 % of the nitrogen demand, primarily because nitrogen is lost through air and water. This, coupled with the overall territorial diagnosis, led us to revisit the idea of using the current situation (based on 2018 data) as a baseline for future bioeconomy trajectories. We suggest that these should rather be compared to a projected baseline accounting for ongoing basic mitigation efforts, estimated for France at 8.5 MtCO2-eq·y−1.

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The use of glyphosate-based herbicides (GBHs) to control weeds has increased exponentially in recent decades, and their residues and degradation products have been found in soils across the globe. GBH residues in soil have been shown to affect plant physiology and specialised metabolite biosynthesis, which, in turn, may impact plant resistance to biotic stressors. In a greenhouse study, we investigated the interactive effects between soil GBH residues and herbivory on the performance, phytohormone concentrations, phenolic compound concentrations and volatile organic compound (VOC) emissions of two woodland strawberry (Fragaria vesca) genotypes, which were classified as herbivore resistant and herbivore susceptible. Plants were subjected to herbivory by strawberry leaf beetle (Galerucella tenella) larvae, and to GBH residues by growing in soil collected from a field site with GBH treatments twice a year over the past eight years. Soil GBH residues reduced the belowground biomass of the susceptible genotype and the aboveground biomass of both woodland strawberry genotypes. Herbivory increased the belowground biomass of the resistant genotype and the root–shoot ratio of both genotypes. At the metabolite level, herbivory induced the emission of several VOCs. Jasmonic acid, abscisic acid and auxin concentrations were induced by herbivory, in contrast to salicylic acid, which was only induced by herbivory in combination with soil GBH residues in the resistant genotype. The concentrations of phenolic compounds were higher in the resistant genotype compared to the susceptible genotype and were induced by soil GBH residues in the resistant genotype. Our results indicate that soil GBH residues can differentially affect plant performance, phytohormone concentrations and phenolic compound concentrations under herbivore attack, in a genotype-dependent manner. Soil GBH altered plant responses to herbivory, which may impact plant resistance traits and species interactions. With ongoing agrochemical pollution, we need to consider plant cultivars with better resistance to polluted soils while maintaining plant resilience under challenging environmental conditions.

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Reindeer (Rangifer tarandus) pastoralism utilizes vast boreo-arctic taiga and tundra as grazing land. Highly fluctuating population sizes pose major challenges to the economy and livelihood of indigenous herder communities. In this study we investigated the effect of population fluctuations on core provisioning and regulating ecosystem services in two Sámi reindeer herding districts with contrasting fluctuation trends. We compared 50-year long time series on herd size, meat production, forage productivity, carbon footprint, and CO2-equivalence metrics for surface albedo change based on the radiative forcing concept. Our results show, for both districts, that the economic benefits from the provisioning services were higher than the costs from the regulating services. Still, there were major contrasts; the district with moderate and stable reindeer density gained nearly the double on provisioning services per unit area. The costs from increasing heat absorption due to reduction in surface albedo caused by replacement of high-reflective lichens with low-reflective woody plants, was 10.5 times higher per unit area in the district with large fluctuations. Overall, the net economic benefits per unit area were 237 % higher in the district with stable reindeer density. These results demonstrate that it is possible to minimize trade-offs between economic benefits from reindeer herding locally and global economic costs in terms of climate-regulating services by minimizing fluctuations in herds that are managed at sustainable densities.

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Herbivores play a crucial role in shaping tundra ecosystems through their effects on vegetation, nutrient cycling, and soil abiotic factors. Understanding their habitat use, co-occurrence, and overlap is therefore essential for informing ecosystem-based management and conservation. In the High Arctic, only a marginal proportion of the land area is vegetated, and climate change is impacting herbivore population sizes and their habitats. In this study, we assessed the spatial habitat overlap of a vertebrate herbivore community based on: 1) regional predictive summer habitat suitability models for the resident Svalbard reindeer (Rangifer tarandus platyrhynchus), resident Svalbard rock ptarmigan (Lagopus muta hyperborea), and the migratory pink-footed goose (Anser brachyrhynchus), and 2) presence of fecal pellets, reflecting the annual habitat use of reindeer, ptarmigan, and geese, including the pink-footed goose and barnacle goose (Branta leucopsis). Our findings revealed that only small proportions of the available land cover (~ 12516 km2; all land area excluding glaciers and freshwater) are suitable for each of the species (habitat suitability [HS] > 0.5): reindeer (22%), ptarmigan (11%), and pink-footed goose (4%). Overlapping suitable habitat [HS > 0.5] for reindeer and goose accounted for only 3% of the total vegetated area (~ 8848 km2) and was primarily found in heath and moist habitats dominated by mosses, graminoids, and herbaceous plants. The overlapping suitable habitat for reindeer and ptarmigan covered 8% of the vegetated area, predominantly in higher elevation ridges with vegetation on drier substrates. The shared habitat for ptarmigan and goose, and all three species of herbivores, was less than 1% of the vegetated area. Additionally, an assessment of fecal pellets suggested that the highest overlap in habitat use among reindeer and goose occurred in bird cliff moss tundra, followed by moss tundra and heath habitats. The small proportion of the vegetated area suitable for all three herbivores indicates a high degree of habitat differentiation. Therefore, different habitats need to be considered for the management and conservation of resident and migratory herbivore species in this High Arctic Archipelago. Moreover, our results underscore the importance of the small but productive parts of the landscape that were used by all herbivores. Goose, habitat suitability, management, ptarmigan, reindeer

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Lingonberry (Vaccinium vitis-idaea L.) grows in a range of nature types in the boreal zone, and understanding factors affecting the abundance of the plant, as well as mapping its spatial distribution, is important. The abundance of the species can be an indicator of ecosystem changes, and lingonberry can also be a source for commercial utilisation of berry resources. Using country-wide data from 6404 field plots of the Norwegian national forest inventory (NFI), we modelled the relationship between lingonberry cover and airborne laser scanning (ALS) and satellite metrics and bioclimatic variables describing the forest structure, terrain, soil properties and climate using a generalised mixed-effects model with a quasipoisson distribution. The validation carried out with an independent set of 2124 NFI plots indicated no obvious bias in predictions. The most important predictors were found to be interactions between dominant tree species, stand basal area and latitude, as well as the reflectance in the near-infrared band from Sentinel-2 satellite imagery, the dominant height based on the ALS variable and the long-term mean summer (June–August) temperature. The results provide an indicator of the effects of global warming, as well as the possibility of giving forest management prescriptions that favour lingonberry and locating the most abundant lingonberry sites in Norwegian forests.

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Understanding the effects of variation in resource availability and habitat disturbance on the ecology of mammals is vital for successful conservation management. In this study, we examined how human disturbances, resource availability and elevation gradients influence mammal assemblages in both managed coffee forest and natural forest of the Belete-Gera National Forest Priority Area, southwestern Ethiopia. We surveyed mammals using motion-detecting infrared camera traps in 90 locations for a total of 4142 camera days. We measured distance from main roads and settlements as disturbance factors, and distance from water sources, key grazing sites, and forest edges and woody plant diversity as resource variables. We assessed the mammal assemblages in coffee forest and natural forests using generalized linear models. Further, we used linear modelling to compare the relationships of mammal detection rates by feeding guilds and body size to resource variables. In total, we recorded 8815 videos identifying 23 different mammal species. The mammal assemblages in coffee forests were negatively associated with increasing distances from key grazing sites, water sources, and elevation. In contrast, the association with increasing distance from the road and woody plant diversity was positive. In addition, herbivores and large (25–200 kg) and very large (≥200 kg) mammals, were all negatively associated with increasing distance from the natural forest edges. With the conversion of natural forest to coffee forest and the intensification of coffee forest management, sustainable management of key grazing sites, water sources, and diverse woody plant species will be essential to the conservation of mammals. In addition, to ensure mammal conservation, adjacent natural forests around coffee forests should also be protected.

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Understanding how the nutritional properties of food resources drive foraging choices is important for the management and conservation of wildlife populations. For moose (Alces alces), recent experimental and observational studies during the winter have shown macronutrient balancing between available protein (AP) and highly metabolizable macronutrients (total non-structural carbohydrates [TNC] and lipids). Here, we combined the use of continuous-recording camera collars with plant nutrient analyses and forage availability measurements to obtain a detailed insight into the food and nutritional choices of three wild moose in Norway over a 5-day period in summer. We found that moose derived their macronutrient energy primarily from carbohydrates (74.2%), followed by protein (13.1%), and lipids (12.7%). Diets were dominated by deciduous tree browse (71%). Willows (Salix spp.) were selected for and constituted 51% of the average diet. Moose consumed 25 different food items during the study period of which 9 comprised 95% of the diet. Moose tightly regulated their intake of protein to highly metabolizable macronutrients (AP:TNC + lipids) to a ratio of 1:2.7 (0.37 ± 0.002SD). They did this by feeding on foods that most closely matched the target macronutrient ratio such as Salix spp., or by combining nutritionally imbalanced foods (complementary feeding) in a non-random manner that minimized deviations from the intake target. The observed patterns of macronutrient balancing aligned well with the findings of winter studies. Differential feeding on nutritionally balanced downy birch (Betula pubescens) leaves versus imbalanced twigs+leaves across moose individuals indicated that macronutrient balancing may occur on as fine a scale as foraging bites on a single plant species. Utilized forages generally met the suggested requirement thresholds for the minerals calcium, phosphorus, copper, molybdenum, and magnesium but tended to be low in sodium. Our findings offer new insights into the foraging behavior of a model species in ungulate nutritional ecology and contribute to informed decision-making in wildlife and forest management.

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Geographical distribution and diversity patterns of bird species are influenced by climate change. The Rouget's rail (Rougetius rougetii) is a ground-dwelling endemic bird species distributed in Ethiopia and Eritrea. It is a near-threatened species menaced by habitat loss, one of the main causes of population declines for bird species. The increasing effects of climate change may further threaten the species’ survival. So far, the spatial distribution of this species is not fully documented. With this study, we develop current potential suitable habitat and predict the future habitat shift of R. rougetii based on environmental data such as bioclimatic variables, population density, vegetation cover, and elevation using 10 algorithms. We evaluated the importance of environmental factors in shaping the bird's distribution and how it shifts under climate change scenarios. We used 182 records of R. rougetii from Ethiopia and nine bioclimatic, population density, vegetation cover, and elevation variables to run the 10 model algorithms. Among 10 algorithms, eight were selected for ensembling models according to their predictive abilities. The current suitable habitats for R. rougetii were predicted to cover an area of about 82,000 km2 despite being highly fragmented. The model suggested that temperature seasonality (bio4), elevation, and mean daily air temperatures of the driest quarter (bio9) contributed the most to delimiting suitable areas for this species. R. rougetii is sensitive to climate change associated with elevation, which leads shrinking distribution of suitable areas. The projected spatial and temporal pattern of habitat loss of R. rougetii suggests the importance of climate change mitigation and implementing long-term conservation and management strategies for this threatened endemic bird species.

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Introduction: Production of strawberries in greenhouses and polytunnels is gaining popularity worldwide. This study investigated the effect of reuse of coir and peat, two substrates commonly adapted to soilless strawberry production, as well as stand-alone wood fiber from Norway spruce, a promising substrate candidate. Methods: The experiment was performed in a polytunnel at NIBIO Apelsvoll, Norway, and evaluated both virgin substrates, as well as spent materials that were used in one or two years. Yield, berry quality and plant architecture of the strawberry cultivar ‘Malling Centenary’ were registered. In addition, chemical and physical properties of virgin and reused substrates were investigated. Results: While plants grown in peat and wood fiber had highest yield in the first year of production, the berry yield was slightly reduced when these substrates were utilized for the second and third time. However, yield was comparable to the yield level attained in new and reused coir. Interestingly, berries grown in wood fiber had a tendency to a higher sugar accumulation. This substrate also produced the highest plants. Stand-alone wood fiber was the substrate with the highest accumulation of nitrogen during the three consecutive production cycles. All three investigated materials revealed a trend for decreased potassium accumulation. Wood fiber is characterized by the highest percentage of cellulose, however after three years of production the cellulose content was reducedto the same levels as for coir and peat. Discussion: Implementation of wood fiber as a growing medium, as well as general practice of substrate reuse can be therefore an achievable strategy for more sustainable berry production.

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Compared to fluctuating soil water (FW) conditions, stable soil water (SW) can increase plant water use efficiency (WUE) and improve crop growth and aboveground yield. It is unknown, however, how stable and fluctuating soil water affect root vegetables. Here, the effects of SW and FW were studied on cherry radish in a pot experiment, using negative pressure irrigation and conventional irrigation, respectively. The assessed effects included agronomic parameters, physiological indices, yield, quality and WUE of cherry radish. Results showed that under similarly average soil water contents, compared with FW, SW increased plant photosynthetic rate, stomatal conductance and transpiration rate, decreased leaf proline content by 13.7–73.3% and malondialdehyde content by 12.5–40.0%, and increased soluble sugars content by 6.3–22.1%. Cherry radish had greater biomass accumulation and nutrient uptake in SW than in FW. Indeed, SW increased radish output by 34.6–94.1% with no influence on root/shoot ratio or root quality. In conclusion, soil water stability affected directly the water physiological indicators of cherry radish and indirectly its agronomic attributes and nutrient uptake, which in turn influenced the crop biomass and yield, as well as WUE. This study provides a new perspective for improving agronomy of root crops and WUE through managing soil water stability.

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Root-knot nematodes (Meloidogyne spp.) are serious pests of most food crops, causing up to 100% yield loss. Nevertheless, commercial nematicides are costly and harmful to the environment. While the nematicidal potential of crustacean and synthetic chitin has been demonstrated globally, research on the potential of insect-derived chitin for nematode control has received limited attention. Here, seven chitin-fortified black soldier fly frass fertilizer extracts (chFE) were assessed for their suppressiveness of Meloidogyne incognita and impacts on spinach growth in comparison with a commercial nematicide using in vitro and in vivo bioassays. The performance of chFE and control treatments was assessed by determining their effects on nematode egg hatchability; infective juvenile (J2) mortality and paralysis; number of galls, egg masses, and J2s per plant; and spinach root and shoot biomass. In vitro results showed that chFE and commercial nematicide suppressed nematode egg hatchability by 42% and 52%, respectively, relative to the control (sterile distilled water). Up to 100% paralysis was achieved when M. incognita J2s were exposed to either chFE or commercial nematicide. Further, the J2 mortality achieved using chFE (95%) was comparable to the value achieved using commercial nematicide (96%); in all treatments, mortality increased with exposure time. Similarly, up to 85% suppression of gall development was achieved when spinach plants were grown in soil drenched with chFE; up to 79% reduction in egg mass formation and 68% suppression of J2 development in the root system were achieved using chFE. Also, chFE application significantly increased spinach root and shoot biomass by 54%–74% and 39%–58%, respectively, compared to commercial nematicide. Our findings demonstrate the nematicidal potential of chFE and its benefits on crop production. Thus, chFE could be considered as a promising multipurpose, regenerative, and cost-effective input for sustainable management of plant-parasitic nematodes and enhancement of crop yield.

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Phytophthora cactorum is a plant pathogenic oomycete that causes crown rot in strawberry leading to significant economic losses every year. To invade the host, P. cactorum secretes an arsenal of effectors that can manipulate host physiology and impair its defense system promoting infection. A transcriptome analysis was conducted on a susceptible wild strawberry genotype (Fragaria vesca) 48 hours post inoculation with P. cactorum to identify effectors expressed during the early infection stage. The analysis revealed 4,668 P. cactorum genes expressed during infection of F. vesca. A total of 539 secreted proteins encoded by transcripts were identified, including 120 carbohydrate-active enzymes, 40 RXLRs, 23 proteolytic enzymes, nine elicitins, seven cysteine rich proteins, seven necrosis inducing proteins and 216 hypothetical proteins with unknown function. Twenty of the 40 RXLR effector candidates were transiently expressed in Nicotiana benthamiana using agroinfiltration and five previously unreported RXLR effector genes (Pc741, Pc8318, Pc10890, Pc20813, and Pc22290) triggered cell death when transiently expressed. The identified cell death inducing RXLR effectors showed 31–66% identity to known RXLR effectors in different Phytophthora species having roles in pathogenicity including both activation and suppression of defense response in the host. Furthermore, homology analysis revealed that these cell death inducing RXLR effectors were highly conserved (82 - 100% identity) across 23 different strains of P. cactorum originating from apple or strawberry.

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Introduction: The first small scale cultivation of potatoes in the Nordic countries began roughly 300 years ago, and later became an important staple food in the region. Organized conservation efforts began in the 1980s, and today, potato landraces, improved varieties, and breeding lines are conserved in genebanks at the Nordic Genetic Resource Center (NordGen), Sweden, and the Norwegian Genetic Resource Centre (NGS), Norway, as well as at potato breeding companies across Nordic countries. All these collections house a diverse array of genotypes with local names and local growing histories from the whole region. However, the presence of duplicates, and inconsistent naming has led to confusion. Methods: In this study, 198 accessions of cultivated potato (Solanum tuberosum L.) have been genotyped with 62 microsatellite (SSR) markers. The analyzed accessions came from three collections: 43 accessions from the Danish Potato Breeding Foundation in Vandel (LKF-Vandel), 90 from NordGen and 65 from NGS. Results and discussion: The genetic analysis revealed 140 unique potato genotypes and 31 groups/clusters of duplicates, most of which contained duplicate pairs and the others three to ten accessions. Several accessions with distinct names were genetically identical or very similar, suggesting historical sharing, and regional distribution of seed potatoes, leading to the emergence of diverse local names. Moreover, many improved varieties from early potato breeding were revealed to have duplicates that have been considered Nordic landraces. Furthermore, potato accessions with identical names but originating from different collections were confirmed to be duplicates. These findings have already influenced management decisions and will further improve management practices for Nordic potato collections. Additionally, this new knowledge will benefit Nordic potato breeding efforts and allow for the dissemination of more accurate information to other users of potato diversity.

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Introduction: Plantations located outside the species distribution area represent natural experiments to assess tree tolerance to climate variability. Climate change amplifies warming-related drought stress but also leads to more climate extremes. Methods: We studied plantations of the European larch (Larix decidua), a conifer native to central and eastern Europe, in northern Spain. We used climate, drought and tree-ring data from four larch plantations including wet (Valgañón, site V; Santurde, site S), intermediate (Ribavellosa, site R) and dry (Santa Marina, site M) sites. We aimed to benchmark the larch tolerance to climate and drought stress by analysing the relationships between radial growth increment (hereafter growth), climate data (temperature, precipitation, radiation) and a drought index. Results: Basal area increment (BAI) was the lowest in the driest site M (5.2 cm2 yr-1; period 1988–2022), followed by site R (7.5 cm2 yr-1), with the youngest and oldest and trees being planted in M (35 years) and R (150 years) sites. BAI peaked in the wettest sites (V; 10.4 cm2 yr-1; S, 10.8 cm2 yr-1). We detected a sharp BAI reduction (30% of the regional mean) in 2001 when springto-summer conditions were very dry. In the wettest V and S sites, larch growth positively responded to current March and June-July radiation, but negatively to March precipitation. In the R site, high April precipitation enhanced growth. In the driest M site, warm conditions in the late prior winter and current spring improved growth, but warm-sunny conditions in July and dry-sunny conditions in August reduced it. Larch growth positively responded to spring-summer wet conditions considering short (1-6 months) and long (9-24 months) time scales in dry (site M) and wet-intermediate (sites S and R) sites, respectively. Discussion: Larch growth is vulnerable to drought stress in dry slow-growing plantations, but also to extreme spring wet-cloudy events followed by dry-hot conditions in wet fast-growing plantations.

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Potato production faces major challenges from inadequate soil fertility, and nematode infestation, yet synthetic fertilizers and nematicides are costly and harmful to the environment. This study explored the potential of chitin-fortified black soldier fly-composted organic fertilizer (BSFCOF) as a multipurpose organic fertilizer amendment for enhancing potato yield and suppressing potato cyst nematodes (PCN). The BSFCOF was applied at a rate equivalent to 150 kg N ha-1 and fortified with chitin from black soldier fly pupal exuviae at inclusion rates equivalent to 0.5, 1, 2, 3, 4 and 5% chitin. Data were collected on potato growth characteristics, PCN population densities, and soil chemical properties for two growing cycles. Results showed that chitin fortified BSFCOF significantly improved potato growth parameters, chlorophyll concentration, marketable tuber yield and number of marketable tubers. The marketable tuber yield achieved using chitin-fortified BSFCOF was 70 – 362%, and 69 – 238% higher than the values achieved using unfertilized soil during the first and second growing cycles, respectively. Soil amendment with chitin-fortified BSFCOF significantly reduced the number of cysts per 200 g soil-1, number of eggs and J2 per cyst-1, eggs g-1 soil and reproduction rate by 32 – 87%, 9 – 92%, 31– 98% and 31 – 98%, respectively. The PCN suppression increased with chitin inclusion rates. There were significantly higher values for soil pH, ammonium nitrogen, nitrate nitrogen, available phosphorus, calcium, magnesium, potassium, and cation exchange capacity in soil amended with BSFCOF compared to unamended soil. This study demonstrates that BSFCOF fortified with 5% chitin is an effective soil enhancer with multiple benefits, including improved soil fertility, potato performance, and effective management of potato cyst nematodes.

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Non-steady-state chambers are often used for greenhouse gas flux measurements, and while there are recommendations on how long to keep the chamber closed, it is less investigated to what extent the length of the chamber closure period affects the estimated flux rates and which closure periods may provide the most accurate linear and non-linear flux estimates. Previous studies have shown that the closure of non-steady-state chambers induces a non-linear concentration development inside the chamber, even across short chamber closure periods, and that both linear and non-linear flux estimates are impacted by the chamber closure period itself. Based on 3,159 individual soil CO2 and CH4 flux measurements, we analyzed how linear regression and Hutchinson and Mosier (1981) modeled flux estimates are affected by the length of the chamber closure period by increasing it in increments of 30 sec, with a minimum and maximum chamber closure period of 60 and 300 sec, respectively. Across all detected flux measurements, the effect of chamber closure period length varied between 1.4–8.0 % for linear regression estimates and between 0.4–17.8 % for Hutchinson–Mosier estimates, and the largest effect sizes were observed in high flux regions. While both linear regression and Hutchinson–Mosier based estimates decreased as the chamber closure period increased, we observed a clear convergence of flux estimates as shorter and longer chamber closure periods were used for linear regression and Hutchinson–Mosier based estimation, respectively. This suggests using closure periods as short as possible for linear regression flux estimation or ensuring long-enough closure periods to observe a stabilization of Hutchinson–Mosier flux estimates over time. This analysis was based on soil flux measurements, but because the perturbation of the concentration gradient is related to the non-steady-state chamber technique rather than the measured ecosystem component, our results have implications for all flux measurements conducted with non-steady-state chambers.

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Rearing of replacement heifers makes up a significant part of the total costs in dairy farming. Nevertheless, the average age at first calving for dairy heifers still stays well above 2 years in many countries. This study examined the economic and environmental impacts of increased heifer growth rates and reduced replacement rates on Norwegian dairy farms. The current average growth rate in Norway (baseline scenario) was compared to an accelerated growth rate scenario. Within each of the two growth rate scenarios, we compared three different cow replacement rates. A farm account survey dataset containing physical and economic data on 311 Norwegian farms was clustered into three farm groups: small, medium, and large. To model economic consequences, we used the whole-farm linear programming model ScotFarm. A life cycle analysis model was used to model the environmental impacts of the baseline scenario and an accelerated growth rate scenario on the three farm groups. Accelerated heifer growth rate had a positive effect (14–28%) on farm annual gross margin depending on farm size. While accelerated growth rate resulted in only minor reductions in total emissions at farm level compared to the baseline scenario, reduced replacement rate lowered total farm level emissions by up to 8%, and emissions per unit of output by up to 6%. We conclude that an accelerated heifer growth rate scenario could potentially increase farm gross margin by some 14–28% compared with a baseline growth rate scenario. Reducing the replacement rate would be more efficient to reduce farm−level greenhouse gas emissions.

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Small ruminant (sheep and goat) production of meat and milk is undertaken in diverse topographical and climatic environments and the systems range from extensive to intensive. This could lead to different types of welfare compromise, which need to be managed. Implementing Precision Livestock Farming (PLF) and other new or innovative technologies could help to manage or monitor animal welfare. This paper explores such opportunities, seeking to identify promising aspects of PLF that may allow improved management of welfare for small ruminants using literature search (two reviews), workshops in nine countries (France, Greece, Ireland, Israel, Italy, Norway, Romania, Spain, and the United Kingdom) with 254 stakeholders, and panels with 52 experts. An investigation of the main welfare challenges that may affect sheep and goats across the different management systems in Europe was undertaken, followed by a prioritisation of animal welfare issues obtained in the nine countries. This suggested that disease and health issues, feed access and undernutrition/malnutrition, maternal behaviour/offspring losses, environmental stressors and issues with agonistic behavioural interactions were important welfare concerns. These welfare issues and their indicators (37 for sheep, 25 for goats) were categorised into four broad welfare indicator categories: weight loss or change in body state (BWC), behavioural change (BC), milk yield and quality (MY), and environmental indicators (Evt). In parallel, 24 potential PLF and innovative technologies (8 for BWC; 10 for BC; 4 for MY; 6 for Evt) that could be relevant to monitor these broad welfare indicator categories and provide novel approaches to manage and monitor welfare have been identified. Some technologies had the capacity to monitor more than one broad indicator. Out of the 24 technologies, only 12 were animal-based sensors, or that could monitor the animal individually. One alternative could be to incorporate a risk management approach to welfare, using aspects of environmental stress. This could provide an early warning system for the potential risks of animal welfare compromise and alert farmers to the need to implement mitigation actions.

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Biochar, which is the product of biomass pyrolysis, has been suggested as a feed supplement to improve performance in livestock systems and reduce greenhouse gas emissions. The aim of the current study was to investigate in vitro and in vivo potential of biochar to favourably modify rumen fermentation (e.g., an increase in total Short Chained Fatty Acid (SCFA) concentration and a change in SCFA profile), reduce methane emission and increase sheep growth performance. Four concentrates were produced with biochar inclusion of 0, 10, 23 and 46 g/kg DM. The experimental diets for the in vitro experiments consisted of straw and concentrate in a 60:40 ratio and included measurements of total gas and methane (CH4) production, pH, ammonia nitrogen, SCFA, and microbial assays (total bacteria and methanogenic archaea). Two in vivo experiments were performed where the animals received ad libitum forage with 0.4 kg concentrate daily. Experiment 1 investigated the daily DM intake of sheep while experiment 2 investigated daily growth rate and CH4 emission of lambs. The inclusion of biochar had no impact on in vitro total gas production (ml/200 mg DM substrate) (P = 0.81) and CH4 production (ml/200 mg DM substrate) (P = 0.93). In vitro total SCFA concentration increased (P < 0.05) while acetate to propionate ratio (A:P) tended to decrease (P = 0.05) with both doses of biochar. Total bacteria decreased with the highest biochar inclusion in vitro (P < 0.05). Sheep’s DM intake (kg/d) increased when low and medium levels but not when a higher level of biochar was added to the diet (P < 0.001). The inclusion of biochar did not significantly impact the lamb’s daily growth rate (g/d) (P = 0.61) or enteric CH4 emissions (g/kg DM) (P = 0.43). We conclude that biochar supplementation had no favourable impacts on in vitro and in vivo CH4 production or on lamb’s growth rate. Further research with well-characterised biochar is needed to gain a better understanding of the potential of biochar as a feed additive for ruminant livestock.

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I en årrekke har det pågått politiske diskusjoner og rettslige prosesser om hvordan statsgrunn i Nordland og Troms skal forvaltes. I denne artikkelen tar vi utgangspunkt i spenningene som har oppstått som følge av at antatt like utmarksområder forvaltes ulikt i ulike deler av landet. Mens fjelloven og statsallmenningsloven finnes sør for Nordland, er det Finnmarksloven som regulerer utmarka lengre nord. På statsgrunn i Nordland og Troms er det Statskog SF som har forvaltningsansvaret. Gjennom en kombinasjon av kvalitative metoder undersøker vi hvordan et utvalg aktører erfarer og forholder seg til forvaltningen av statsgrunn i Salten-regionen i Nordland. Vi finner tre dominerende tema som både tilhengere av dagens forvaltningsmodell og de som ønsker å innføre fjelloven og lokale fjellstyrer vektlegger i sin argumentasjon; økonomi, kompetanse og rettigheter. Alle aktørene posisjonerer seg med hensyn til de alternative forvaltningsmodellene, men det er ulikt hvor tydelig de tar stilling. Mens kommunene og lokale aktører mener det er på overtid å få innført fjelloven, vektlegger andre at Statskog sikrer allmennheten tilgang til å bruke utmarka. Kryssende konfliktlinjer, både langs sentrum-periferiaksen og mellom lokale aktører bidrar til å opprettholde status quo. Uavklarte samiske rettighetsforhold kompliserer situasjonen ytterligere.

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«KAMPEN OM utmarka» var tittelen på den nasjonale temakonferansen som Norsk Bonde- og Småbrukarlag inviterte til på Gardermoen seinhausten 2022. Nett den tittelen var sjølvsagt ikkje tilfeldig, tvert om speglar den kjensla jamt fleire beitebrukarar i utmarka opplever om dagen, dei opplever at det går føre seg ein kamp om kva utmarka er og kva den skal vere. Denne artikkelen handlar nettopp om kva utmarka er. Den handlar om kva me grunnleggande sett snakkar om når me snakkar om utmark. Sagt på ein annan og litt meir filosofisk måte så handlar artikkelen om utmarkas sosiale ontologi og om korleis nett denne ontologien spelar seg ut i den daglege praksisen og forvaltinga av utmarka. Forfattarane argumenterer for at etter fleire tusen år med agrar dominans der jordbrukets interesser og behov har vore mesta einerådande, er det no forskjellige og konkurrerande ontologiar om kva utmarksområda eigentleg er. Med dette melder også spørsmålet seg om me i det heile teke kan og bør snakka om utmark lenger i forvaltning, forsking og politikk. For det kan skjula og tåkelegga, meir enn det klargjer for dei mange konfliktane som finn stad.

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Who interacts with whom is a key question in community and network ecology. The concept that these interactions may be driven by a match between the traits of consumer and resource species is known as trait-matching. If trait-matching would allow for general predictions of interaction structure based on sufficiently few and easily-measurable traits, then this approach could replace the laborious description of each individual pairwise interaction. To resolve imprints of trait-matching in a species-rich tri-trophic Salix–galler–parasitoid network, and to identify the most relevant traits, we applied five different methods, each approaching the same phenomenon from a different perspective. As traits, we used, body sizes, gall type (position on plant, structure of gall) and phenology, among others, as well as phylogenetic proxies. When jointly applied, the methods demonstrate distinctly different imprints of traits within the two bipartite network elements (Salix–galler versus galler–parasitoid interactions). Of the galler–parasitoid sub-network's interactions, approximately half were explainable by the species traits used; of the Salix–galler sub-network's interactions, traits explained at most two-fifths. Gall type appeared to be the most important structuring trait in both networks. Phylogeny explained as much, or more than did our tested traits, suggesting that traits may be conserved and phylogeny therefore an effective proxy. Overall, the more specialized structure of the Salix–galler network versus the more nested structure of the galler–parasitoid network meant that different methods were more effective at capturing interactions and interaction structure in the different sub-networks. Thus, our analysis reveals how structuring impacts may vary even between levels within the same multitrophic network, and calls for comparative analyses of trait matching across a wide set of systems and methods.

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The ecological niche is a fundamental concept in ecology that can be used in order better understand species relationships. The overlap in species niches provides a measure of the likelihood for species to co-occur. Most approaches that quantify niche overlap have been based on distance and similarity indices, for pairwise combinations of species. In this paper, we suggest that niche overlap can be calculated from the predictions of a model. Using a statistical model to predict niche overlap provides various benefits, includes the possibility to adjust the model to properties of the data. We demonstrate this using an example dataset of an ecological community of Foraminifera species, to which we fit a generalized linear latent variable model (GLLVM). GLLVMs are a flexible class of models that allow to estimate the distribution of species using both measured environmental predictors and residual covariation between species. We demonstrate how to calculate niche overlap from GLLVMs for any combination of species, and separately for different environments. Predicting niche overlap from a model further expands the toolset available to ecologists for the exploration of species co-occurrence patterns.

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There is an increasing need for ecosystem-level distribution models (EDMs) and a better understanding of which factors affect their quality. We investigated how the performance and transferability of EDMs are influenced by 1) the choice of predictors and 2) model complexity. We modelled the distribution of 15 pre-classified ecosystem types in Norway using 252 predictors gridded to 100 × 100 m resolution. The ecosystem types are major types in the ‘Nature in Norway' system mainly defined by rule-based criteria such as whether soil or specific functional groups (e.g. trees) are present. The predictors were categorised into four groups, of which three represented proxies for natural, anthropogenic, or terrain processes (‘ecological predictors') and one represented spectral and structural characteristics of the surface observable from above (‘surface predictors'). Models were generated for five levels of model complexity. Model performance and transferability were evaluated with data collected independently of the training data. We found that 1) models trained with surface predictors only performed considerably better and were more transferable than models trained with ecological predictors, and 2) model performance increased with model complexity, levelling off from approximately 10 parameters and reaching a peak at approximately 20 parameters, while model transferability decreased with model complexity. Our findings suggest that surface predictors enhance EDM performance and transferability, most likely because they represent discernible surface characteristics of the ecosystem types. A poor match between the rule-based criteria that define the ecosystem types and the ecological predictors, which represent ecological processes, is a plausible explanation for why surface predictors better predict the distribution of ecosystem types. Our results indicate that, in most cases, the same models are not well suited for contrasting purposes, such as predicting where ecosystems are and explaining why they are there.

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Norwegian apple ciders have recently gained attention at the levels of international competitiveness. Accordingly, a comparative study on the chemical composition of selected Norwegian and French apple ciders was conducted to gain knowledge on what ubiquitous chemical parameters make the Norwegian ciders different from ciders from well-established producing regions. A total of 43 ciders, 24 Norwegian and 19 French, in the category of acidic dominant ciders, were included in the study. Ethanol, individual sugars and organic acids, pH, total phenols, aroma compounds including esters, C6-alcohols, volatile phenols and terpenoids, were analysed. Norwegian ciders showed higher contents in ethanol, malic and citric acids, whereas total phenols, pH, glucose, and fructose were higher in French counterparts. Regarding the aromatic profile, no significant differences were observed for C6-alcohols. In contrast, differences were more expressed in the case of esters and volatile phenols. Norwegian ciders were characterised by higher average concentration for all the groups of esters, with the most important differences measured for higher alcohol acetates. Norwegian ciders also displayed higher contents of 4-vinylphenol and 4-vinylguaiacol while French ciders contained substantially higher levels of 4-ethylphenol and 4-ethylguaiacol. These results are in mutual correlation with the empirical observation reporting Norwegian apple ciders as more acidic, alcoholic and with lighter body but fruitier profile. Whereas French ciders are often perceived with more structure and animalistic profile.

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In the present work we have investigated the effects of abiotic and biotic factors on the growth and quality of carrots. The experiment tested how precipitation above field capacity (WATER) vs. no precipitation (DROUGHT) affect carrot growth and storability. Each treatment period lasted three weeks. We found no yield difference between the treatments at harvesting the carrots (6.6 vs. 6 t daa‑1) and the proportion of fresh roots was generally around 85%. High precipitation, especially in the latter part of the growth period, resulted in a higher proportion of cracked roots, number of roots with a lighter colour, rot in the upper part of the root and the occurrence of enlarged cork cells. After storage, we did not see any difference between the different treatments in the proportion of fresh roots. There was a slight tendency for tip rot to increase during drought at the end of the season. The soil content of phosphorous (P), potassium (K), magnesium (Mg), calcium (Ca) and sodium (Na) was reduced by high water supply, especially early in the season. The nutrient content in the roots was generally less affected by treatments than the soil mineral content. We found that the content of K and manganese (Mn) was higher at high water supply and the content of zinc (Zn) and ion (Fe) lower. The dry matter content was lowest in the treatments with a high-water supply. As the precipitation influences the soil content of some minerals, we looked at how low pH, low Ca content in the soil, would influence carrot growth. High soil pH (7.4 vs. 5.5) resulted in a higher proportion of roots with fingers when harvesting, but a lower proportion of roots with tip rot after storage (7.8 vs. 3.3%) as well as a higher proportion of healthy roots (83% vs. 67%). The conclusion is that the climatic changes where periods with high precipitation and with drought occur more often require attention to cultivation methods to reduce the negative effects.

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We studied the environmental control of shoot growth and floral initiation in annual shoot plants of four red currant cultivars under phytotron conditions. Under natural day length conditions at Ås, Norway (69°40’N), the cultivars ‘Junifer’, ‘Red Dutch’, and ‘Rosetta’ ceased growing and initiated irregular flower formation at 24 and 18°C in late August, indicating a critical photoperiod of approximately 15 h. At 12°C and under outdoor conditions, the processes were delayed by 3-6 weeks depending on the cultivar, indicating a critical photoperiod of approximately 14 h under Nordic field conditions. In 10-h short day (SD), the cultivars ‘Junifer’, ‘Red Dutch’ and ‘Rovada’ ceased growing within 2-3 weeks at 18 and 24°C and within 2-4 weeks at 12°C, followed by irregular floral initiation. However, in 20-h long day (LD), flower initiation was generally scarce, and with contrasting temperature responses among the cultivars, flower initiation was advanced by low temperature in ‘Red Dutch’ and by high temperature in ‘Rovada’ and ‘Junifer’. Flowering performance in the following spring confirmed these results, which demonstrate that red currants are quantitative SD plants with diverse temperature and photoperiod interactions.

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The chilling requirements of ‘Junifer’, ‘Rovada’ and ‘Red Dutch’ red currants and ‘Mucurines’ and ‘Pax’ gooseberries were studied under controlled environment conditions. Field grown single-stem potted plants were chilled at 0°C from October 15 for 0 to 20 weeks and forced in a lighted greenhouse at 20°C and 18 h photoperiod for 60 days for recording of budbreak and flowering. None of the red currant plants were able to break without chilling, while the number of breaking buds increased linearly with more than four weeks of chilling, and fastest so in ‘Junifer’. ‘Red Dutch’ proved to have a particularly deep and stable dormancy. Comparable but markedly lower chilling requirements were found in the two gooseberry cultivars. While more than 20 weeks of chilling were required for full dormancy release in the red currant cultivars, 16 to 20 weeks were adequate for the ‘Mucurines’ and ‘Pax’ gooseberries, respectively. This compares with a chilling need of 14 weeks at 0°C previously found for most commercial black currant cultivars under the same conditions. The results also confirm that, as previously demonstrated for black currants, flower development requires more chilling than bud break itself also in red currants and gooseberries. This highlights the need for extended chilling of the plants before the plants are set to forcing in modern tunnel production. We also conclude that the red currant cultivar ‘Rovada’ with its large berry trusses seems particularly well suited for tunnel production.

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Fruit yield in wild berry species can vary greatly from year to year. Despite the short growing season and low temperatures in the Arctic region, many small fruit species are thriving under such conditions. Cloudberry (Rubus chamaemorus L.) is a perennial dioecious plant dependent upon insects for pollination. Cloudberries are high-valued, but fruit set and yield can fluctuate substantially between years. Although most commercial harvesting of cloudberries is done from wild stands, a few commercial cultivars are available, and cultivation techniques for natural stands have been developed. There is limited knowledge of variations in cloudberry crops. Increased research on this topic can be crucial for enhancing our knowledge of cloudberry cultivation and having better predictions for increased commercial utilization.

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Mushroom (Agaricus bisporus) and oyster (Pleurotus ostreatus) cultivation generates a vast amount of by-product after the harvest of edible products in the form of used compost, so called spent mushroom composts (SMC) or spent oyster substrate (SOS). In Europe, more than three million tons of SMC are produced every year as a by-product from mushroom cultivation. The management of SMC and SOS has thus become an increasing challenge from an environmental point of view. This spent material has been utilized as growing media, bio-fertilizers, in bioremediation and as a tool to control plant diseases. They have, therefore, a great potential to be implemented in primary food production. The current study investigated the impact of SMC or SOS amendment to peat on plant and microbial growth. The achieved results indicated increased flower and yield potential after SMC amendment to peat compared with SOS. Assessment of microflora in the substrate highlighted higher amount of beneficial microbial groups such as Pseudomonas, in peat and SMC mixtures compared to the ones with peat and SOS.

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The aim of this study was to compare various types of peat-free or peat-reduced growing media on growth and flowering of ‘Purple piruette’ petunia hybrids. In experiment 1, 30 variants of growing media, including commercial peat-based growing media, different peat-reduced and peat-free mixtures based on garden/park waste compost and wood fiber were tested. All the peat-free variants failed in producing normal, healthy plants without chlorosis. A commercial peat-reduced growing medium with peat, garden/park waste-compost and crushed rock material (0-2 mm), base fertilized with chicken manure, and similar growing media mixtures with other types of base fertilizer gave larger plants with more flowers than the peat-based reference. The highest performing mixture with the smallest amount of peat (35% wood fiber, 30% garden park/park waste-compost, 30% peat and 5% sand) gave equal results as the commercial peat-reduced growing medium. In experiment 2, further studies of the effect of peat reduction by incorporation of wood fiber and four compost types were performed. The effect of start fertilizer incorporation to the substrates was also assessed. One of the peat-free variants with compost and wood fiber gave normal plants with rich flowering but didn’t reach the performance of pure peat on plant size. The pH (H2O) of the composts seems to be a key factor for successful substrate mixtures of compost and wood fiber. The composts with highest pH gave small plants and start fertilizer had no effects on the growth. The results show that there is a potential for development of peat-free substrates based on compost and wood fiber presuming that pH (H2O) of the composts is not too high.

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Polyploidy, or genome doubling, has occurred repeatedly through plant evolution. While polyploid plants are used extensively in agriculture and horticulture, they have so far found limited use in forestry. Here we review the potentials of polyploid trees under climate change, and investigate if there is support for increased use. We find that polyploid trees like other plants have consistent increases in cell sizes compared to diploids, and that leaf-area based rates of photosynthesis tend to increase with increasing levels of ploidy. While no particular trend could be discerned in terms of biomass between trees of different ploidy levels, physiology is affected by polyploidization and several studies point towards a high potential for polyploid trees to adapt to drought stress. The ploidy level of most tree species is unknown, and analysis of geographical patterns in frequencies of polyploid trees are inconclusive. Artificial polyploid trees are often created by colchicine and in a few cases these have been successfully applied in forestry, but the effects of induced polyploidization in many economically important tree species remains untested. Polyploids would also be increasingly useful in tree breeding programs, to create synthetic hybrids or sterile triploids that could control unwanted spreading of germplasm in nature. In conclusion, this review suggests that polyploid trees may be superior under climate change in some cases, but that the potential of polyploids is not yet fully known and should be evaluated on a case-to-case basis for different tree species.

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Stress on tree vitality is expected to increase due to climatic extremes in European forests. The decline in vitality of European beech (Fagus sylvatica L.) that has been reported recently, makes it necessary to rethink its future adaptive potential under ongoing climate change. Here we performed a pan European assessment of defoliation chronologies on 414 ICP Forests Level I beech plots, between 1995 and 2022. We investigated the temporal trends, spatial variation, tree-specific patterns as well as climate sensitivity of defoliation at plot level. Various trends emerged and we delineated the plots accordingly: 1) increasing defoliation trends indicating declining vitality (categorized as t1 plots); 2) no trends indicating stable crown condition (t2 plots); 3) decreasing defoliation trends indicating increase in vitality (t3 plots). Spatial variation was found among these plots but no regional grouping or clustering. Tree-specific patterns on 14 % plots were observed, characterized by an expressed population signal of < 0.85, indicating high inter-tree variability. Defoliation was found to be sensitive to climatic variables, mainly to temperature but also precipitation, albeit only for a small percentage of plots. Sensitivity was indicated by statistically significant (p<0.05) Pearson’s correlation coefficients. Moreover, this response depended on month of the year. Climate sensitivity of defoliation also varied across space and plots of different trend categories. It also differed along monthly water balance gradient, further indicating the role of site-specific water availability in mediating the responses to climatic variables. Our study provided basis for long-term defoliation studies, and is a crucial building block to assess beech vitality under potentially changing future climate. Furthermore, such studies will provide more insights into changes in sensitivity and adequate future sites for beech.

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Drought hardening is a nursery technique aimed to enhance early forest plantation establishment under dry conditions, which is a main limiting factors for plantation success. However, the quantitative effectiveness of drought hardening remains unclear. We conducted a meta-analysis to evaluate the influence of different factors in the effectiveness of drought hardening on seedling post-planting survival and growth. Overall, drought hardening did not significantly affect survival or growth, as several factors induced great heterogeneity, but analyses of those factors explained its effectiveness, especially on survival. A longer time between hardening and transplanting strongly reduced survival. Indoor-grown seedlings did not benefit more from hardening than outdoor-grown seedlings. Evaluations of drought hardening effectiveness in pots showed positive effects on survival but negative effects on growth, while no effects were found in large bed experiments. In field experiments, hardening significantly increased survival and growth with site aridity. Survival benefits were independent of species drought tolerance, measured by osmotic potential at the turgor loss point (πtlp), in moderate to high aridity sites. However, in low aridity sites, hardening increased survival in drought-tolerant species but decreased it in drought-intolerant species. Field results showed that hardening benefited shrubs more than trees in angiosperms. In conclusion, drought hardening at the end of nursery cultivation tend to increase post-planting seedling performance particularly in scenarios limiting post-planting root growth such as in arid climates and pot experiments. Our findings highlight the importance of future research on modelling the interaction between these technical features and species water use strategies..

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Forests, especially in the northern latitudes, are vulnerable ecosystems to climate change, and tree-ring data offer insights into growth-climate relationships as an important effect. Using the National Forest Inventory plot network, we analysed these correlations for the two dominant conifer species in Norway – Norway spruce and Scots pine – for the 1960–2020 period. For both species, the June climate was an important driver of radial growth during this period. Countrywide, the climate-growth correlations divided the Norwegian forests into spatial clusters following a broad shift from temperature- to water-sensitivity of growth with latitude and altitude. The clusters were delineated by a mean 1960–2020 June temperature of ca. 12°C for Norway spruce and Scots pine. The annual mean growing season and July temperatures – but not June temperature – has increased by 1.0 °C between the 1960–1990 and 1990–2020 periods, with a slight increase in precipitation. Despite this warming and wetting trend, the long-term growth-climate relationship has remained relatively stable between 1960 and 1990 and 1990–2020 for both species. The threshold between temperature and water-sensitive growth has not changed in the last two 31-year periods, following the stability of the June temperature compared with other months during the growing season. These findings highlight geographically coherent regions in Norway, segregating between temperature- and water-sensitive radial growth for the two major conifer species, temporally stable in the long-term for the 1960–2020 period studied.

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• For more than 20 years, methyl jasmonate (MeJA) has been used to study inducible defenses in conifers and to increase tree resistance to pests and pathogens. Despite the numerous studies on the subject, no attempts have been made to summarize or quantify how MeJA affects resistance and growth in conifers. Here we present a quantitative meta-analysis of the effects of MeJA treatment on the conifer genera Pinus and Picea, two of the most economically and ecologically important tree genera in boreal, temperate, and alpine forests. • A literature search yielded 120 relevant papers. We summarized the key experimental methods used in these papers and performed a meta-analysis of how MeJA affects tree growth and resistance to pests and pathogens. • The results show that MeJA negatively affects tree growth, with an overall effect size of −0.63. The overall effect size of MeJA for tree resistance was −0.76, indicating that MeJA treatment significantly reduces tree damage caused by biotic stressors. • Although our meta-analysis shows that MeJA is effective in enhancing conifer defenses, there are still gaps in our understanding of the durability and ecological consequences of MeJA treatment. We provide suggestions for how future research should be conducted to address these gaps.

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Multiple ecological drivers, along with forest age, determine the species composition of boreal forest ecosystems. However, the role of age in successional changes in forests cannot be understood without taking site conditions, the disturbance regime and forest structure into account. In this study, we ask two research questions: 1. What is the relationship between forest age and overall species composition in older near-natural spruce forests, i.e. forests of age beyond harvest maturity? 2. Do species associated with different forest habitats respond similarly to variation in forest age? Data were collected in 257 Norway spruce dominated 0.25 ha plots from three study areas in Southeastern and Central Norway. Species inventories were conducted for lichens and bryophytes on trees and rocks, vascular plants on the forest floor, and for deadwood-associated bryophytes and polypore fungi. Although NMDS ordination analyses of the total species composition identified a main axis related to the age of the oldest trees in two of the study areas, variation partitioning analyses showed that age explained a small fraction of variation of the species composition compared to site conditions, logging history, forest structure, and differences between the sites in all habitats. The unique variation explained by forest age species was, however, significant for all habitats. The fraction of variation in species composition explained by forest age was the largest for lichens and bryophytes on trees, and for deadwood-associated bryophytes and polypore fungi. Our results suggest that practical mapping of near-natural forests for management purposes inventories should include site conditions, forest structure and between site differences in addition to forest age.

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The cultivated garden strawberry (Fragaria × ananassa) has a rich history, originating from the hybridization of two wild octoploid strawberry species in the 18th century. Two-step reconstruction of Fragaria × ananassa through controlled crossings between pre-improved selections of its parental species is a promising approach for enriching the breeding germplasm of strawberry for wider adaptability. We created a population of reconstructed strawberry by hybridizing elite selections of F. virginiana and F. chiloensis. A replicated field experiment was conducted to evaluate the population's performance for eleven horticulturally important traits, over multiple years. Population structure analyses based on Fana-50 k SNP array data confirmed pedigree-based grouping of the progenies into four distinct groups. As complex traits are often influenced by environmental variables, and population structure can lead to spurious associations, we tested multiple genome-wide association study (GWAS) models. GWAS uncovered 39 quantitative trait loci (QTL) regions for eight traits distributed across twenty chromosomes, including 11 consistent and 28 putative QTLs. Candidate genes for traits including winter survival, flowering time, runnering vigor, and hermaphrodism were identified within the QTL regions. To our knowledge, this study marks the first comprehensive investigation of adaptive and horticultural traits in a large, multi-familial reconstructed strawberry population using SNP markers.

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The sustainable production of perennial grasses in Northern Norway is at risk due to the ongoing climate change. The predicted increase in temperatures and variable weather patterns are further expected to create challenges for winter survival of timothy (Phleum pratense L.). Knowledge about the molecular mechanisms underlying freezing tolerance is crucial for developing robust cultivars. The current study is aimed at identifying genes involved in freezing stress response of timothy and studying gene expression differentiation due to field selection in contrasting environments using RNAseq. Four timothy cultivars were field tested for three years in Tromsø and Vesterålen, in Northern Norway. The surviving material from the field tests, along with plants raised from the original seed lots, were subjected to freezing tests. LT50 values varied across cultivars and materials. Many genes coding for transcription factors and proteins known to play an important role in freezing tolerance, like dehydrins, c-repeat binding factors, and late embryogenesis abundant proteins were upregulated with decreasing temperatures. Moreover, genes associated with glycolysis/gluconeogenesis, TCA cycle, glutathione metabolism, proteasome pathways and genes encoding autophagy-related proteins, plasma membrane-associated proteins, sugar and amino acid transporters had elevated expression in field survivors compared to plants raised from the original material. The lower freezing stress tolerance of field survivors despite the elevated expression of several stress-responsive genes might be due to a combination of selection in the field and the age effect. Furthermore, differences in freezing stress response between northern and southern adapted cultivars and surviving material from two field trial locations are discussed.

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Bilberry (Vaccinium myrtillus L.) is a wild berry species that is prevalent in northern Europe. It is renowned and well-documented for its nutritional and bioactive properties, especially due to its anthocyanin content. However, an overview of biological systems governing changes in other crucial quality traits, such as size, firmness, and flavours, has received less attention. In the present study, we investigated detailed metabolomic and proteomic profiles at four different ripening stages of bilberry to provide a comprehensive understanding of overall quality during fruit ripening. By integrating omics datasets, we revealed a novel global regulatory network of plant hormones and physiological processes occurring during bilberry ripening. Key physiological processes, such as energy and primary metabolism, strongly correlate with elevated levels of gibberellic acids, jasmonic acid, and salicylic acid in unripe fruits. In contrast, as the fruit ripened, processes including flavour formation, cell wall modification, seed storage, and secondary metabolism became more prominent, and these were associated with increased abscisic acid levels. An indication of the increase in ethylene biosynthesis was detected during bilberry development, raising questions about the classification of non-climacteric and climacteric fruits. Our findings extend the current knowledge on the physiological and biochemical processes occurring during fruit ripening, which can serve as a baseline for studies on both wild and commercially grown berry species. Furthermore, our data may facilitate the optimization of storage conditions and breeding programs, as well as the future exploration of beneficial compounds in berries for new applications in food, cosmetics, and medicines.

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In agricultural areas dominated by subsurface drainage, leaching of phosphorus (P) from soils is a concern for downstream water quality. Still, the role of chemical processes in subsoils and organic soils in influencing dissolved P leaching needs to be clarified for better predicting the P leaching. In ten mineral and organic soils, we examined a wide range of chemical characteristics including various P pools and sorption–desorption properties at different soil depths and related those characteristics to leaching of dissolved P at the drain depth in an indoor lysimeter experiment. Results showed significant correlations between different P pools (R2-adj = 0.61 to 0.98, p < 0.001) and between sorption capacity measurements (R2-adj = 0.60 to 0.95, p < 0.001). Some organic soils followed the same patterns in P sorption capacity and P lability as sandy soils but some did not, suggesting organic soils differ among themselves possibly due to differences in origin and/or management. Flow-weighted mean concentrations of dissolved reactive P and dissolved organic P depended on both the labile P pools (labile inorganic and organic P pools, respectively) in the topsoil and P sorption and desorption characteristics in the subsoils. Mass-weighted whole-profile degree of P saturation based on the ammonium lactate extraction method (DPS-AL) was an excellent indicator of flow-weighted mean concentration of total dissolved P (FWMC-TDP) (R2-adj = 0.93, p < 0.001). Two profiles, one with organic soils overlaying on sand and the other with sandy soils in all layers, had the greatest FWMC-TDP among all profiles (316 and 230 µg/L versus 33–84 µg/L) due to the same reason, i.e., large labile P pools in the topsoils, low P sorption capacity in the subsoils, and high whole-profile DPS-AL. All results point to the need to include subsoil characteristics for assessing the risks of dissolved P leaching from both mineral and organic soils. Also, the study suggests the need to investigate further the roles of the origin and management of organic matter and organic P in influencing P lability and dissolved organic P (DOP) leaching, as well as the bioavailability of DOP in recipient waters.

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The evolution of soil structure in agricultural soils is driven by natural and anthropogenic factors including inherent soil properties, climate and soil management interventions, all acting at different spatial and temporal scales. Although the causal relationships between soil structure and these individual factors are increasingly understood, their relative importance and complex interactive effects on soil structure have so far not been investigated across a geo-climatic region. Here we present the first attempt to identify the relative importance of factors that drive the evolution of soil structure in agricultural soils as well as their direction of effect with a focus on the temperate-boreal zone. This was done using a random forest (RF) approach including soil, climate, time, and site factors as covariates. Relative entropy, as quantified by the Kullback-Leibler (KL) divergence, was used as a quantitative index of soil structure, which is derived from the particle-size distribution and soil water retention data, and integrates the effects of soil structure on pores from the micrometre-scale to large macropores. Our dataset includes 431 intact topsoil and subsoil samples from 89 agricultural sites across Sweden and Norway, which were sampled between 1953 and 2017. The relative importance of covariates for the evolution of soil structure was identified and their non-linear and non-monotonic effects on the KL divergence were investigated through partial dependence analysis. To reveal any differences between topsoils (0–30 cm; n = 174) and subsoils (30–100 cm; n = 257), the same analysis was repeated separately on these two subsets. The covariates were able to explain on average more than 50% of the variation in KL divergence for all soil samples and when only subsoil samples were included. However, the predictions were poorer for topsoil samples (≈ 35%), underlining the complex dynamics of soil structure in agricultural topsoils. Parent material was the most important predictor for the KL divergence, followed by clay content for all soil samples and sampling year for only subsoil samples. Mean annual air temperature ranked third and annual precipitation ranked fourth for subsoil samples. However, it remains unclear whether the effects of climate factors are direct (e.g., freezing and thawing, wetting and drying, rainfall impact) or indirectly expressed through interactions with soil management. The partial dependence analysis revealed a soil organic carbon threshold of around 3% below which soil structure starts to deteriorate. Besides this, our results suggest that subsoil structure in the agricultural land of Sweden deteriorated steadily during the 1950′s to 1970′s, which we attribute to traffic compaction as a consequence of agricultural intensification. We discuss our findings in the light of data bias, laboratory methods and multicollinearity and conclude that the approach followed here gave valuable insights into the drivers of soil structure evolution in agricultural soils of the temperate-boreal zone. Theses insights will be of use to inform soil management interventions that address soil structure or soil properties and functions related to it.