Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2025
Forfattere
Quentin Lardy Haldis Kismul Shelemia Nyamuryekung'e Jorid Sandvik Mårten Hetta Mohammad Ramin Vibeke LindSammendrag
Comparative studies between pasture-based dairy production and indoor confinement-based production have demonstrated that including pasture in the diet reduces enteric methane emissions. However, the effects of seasonal access to pasture, where animals are allowed outdoors only during parts of the year, have been less extensively studied. The aim of this study was to assess the effects of providing dairy cows with voluntary access to a production pasture compared with an exercise pasture on their performance and enteric methane emission. Thirty-two lactating Norwegian Red dairy cows, averaging 158 DIM, were divided into 2 groups and used in a changeover experimental design. The treatments included cows given 24-h access to either a production pasture (providing at least 50% of cows' daily DMI) with unlimited fresh grass and restricted indoor feeding, or ad libitum indoor feeding of silage with access to an exercise pasture with no expected herbage intake. Each changeover period included 2 wk of adaptation followed by 2 wk of recording, during which both treatments were fed the same grass silage and concentrates. Milk yield was recorded using an automatic milking unit, and indoor feed intake was recorded using access-controlled feed troughs and concentrate feeders. Enteric methane emissions were monitored using 2 GreenFeed emission monitoring systems: one positioned indoors, and one positioned outdoors adjacent to the production pasture. Cows on production pasture exhibited a lower milking frequency and reduced milk yield compared with cows on exercise pasture. However, cows on production pasture compensated for the lower milk yield by increased concentration of milk solids, suggesting that including a significant amount of pasture in the diet of dairy cows may not compromise energy-corrected milk production. Additionally, cows in the production pasture had significantly lower enteric methane emissions compared with cows in the exercise pasture. In conclusion, incorporating pasture into the diets of dairy cows, even if only for part of the year, has the potential to reduce the carbon footprint of dairy production.
Forfattere
Qiang Liu Mahmoud Mazarji Yeqing Li Lu Feng Hongjun Zhou Quan Xu Alastair James Ward Yajing Wang Jianping Su Chunming Xu Junting PanSammendrag
Humic acid (HA) is an inhibitor that can diminish bioconversion during anaerobic digestion (AD). In this study, a non-metallic nanomaterial, N-doped carbon quantum dots (NCQD), was synthesized to alleviate the HA inhibition, followed by exploring its mechanism. Adding 500 mg/L NCQD prevented HA inhibition by binding to HA or microorganism surfaces, thus avoiding contact between them. This phenomenon, known as shielding inhibition, involves the formation of hydrogen bonds and chemical bonds. The intermolecular force and dissociation constant (KD) between NCQD and HA were determined to be 112.83 ±3.98 nN and 1.0 ±0.07 ×10 7 M, respectively. NCQD could promote electron transfer in AD systems. According to the in-depth microbial analysis, NCQD significantly enhanced the metabolic pathways of methanogenesis and biosynthesis of coenzyme F420. This groundbreaking research demonstrates the dual functionality of NCQD by effectively shielding against HA inhibition and promoting electron transfer. The study also unravels the mechanism of interface interaction, electron transfer, and metabolic pathways, leading to significant breakthroughs in addressing HA inhibition.
Forfattere
Michel VerheulSammendrag
To document effects of High-Pressure-Sodium (HPS) and Light-Emitting Diodes (LED) lamps, six different cucumber cultivars (‘DeeRect’, ‘HiLight’, ‘Imea’, ‘Keirin’, ‘Shakira’ and ‘Topvision’) were grown hydroponically in a semi-commercial greenhouse compartment using standard HPS or LED supplemental top-light from December to March. A PPFD of 240 µmol m-2s-1, 20h a day, was used for both lamp types. In addition, plants were grown with or without LED inter-lighting (45 µmol m-2s-1, 20h a day). Global radiation during the experiment was less than 1.5 MJ m-2day-1. Setpoints for day and night temperatures were 24 and 21 oC respectively. CO2 concentration in the greenhouse was kept at 1100 ppm. Morphological traits (stem length, leaf area, leaf thickness, dry weights), yield (fruit fresh weight and number of fruits) as well as quality parameters were registered. Results show that the use of LED top-light reduced yield considerably compared to HPS top-light, mainly due to a reduction in the number of 1st class fruits harvested. Plants grown using HPS top-light were longer, had more internodes, a higher fruit weight, bigger leaf area and leaf area index (LAI) and ‘thinner’ leaves compared to plants grown using LED top-light. Light use efficiency (g FW mol PAR-1) was highest using HPS or a combination of HPS and LED inter-light and lowest using LED combined with LED inter-lighting, especially at the start of the harvesting period. Huge differences in yield reduction between different cultivars were observed. LED top light reduced the yield of ‘DeeRect’ with 35% and of ‘HiLight’ with 5% compared to HPS top light. Little differences in quality traits were observed between cultivars grown under HPS or LED lamps. However, inter lighting increased fruit weight and fruit quality (color, dry matter content, soluble solid content, chlorophyll content, vitamin C content and storage properties). Causes of differences between lamp types and effects on commercial greenhouse cucumber production in Norway are discussed.
Forfattere
Getachew Birhanu Abera Aryan Bhusal Thea Os Andersen Shuai Wang Nabin Aryal Svein Jarle Horn Lu FengSammendrag
In-situ biomethanation is an efficient process for converting carbon dioxide (CO2) to methane (CH4) using hydrogen (H2) alongside anaerobic digestion (AD) process. However, AD of protein rich substrate often leads to the accumulation of ammonia nitrogen at high concentration. As a major inhibitor, this accumulation affects not only the AD process but also in-situ biomethanation. This study investigated the impact of ammonia nitrogen (0.5–5 g/L) on biomethanation performance using anaerobic moving-bed biofilm reactors (AnMBBRs). Without biofilm/biocarrier support, methane production was significantly inhibited above 3 g/L of ammonia nitrogen. In contrast, AnMBBR maintained high methane yields of 156.5 NmL/Lreactor at 2.5 g/L and 151.3 NmL/Lreactor at 5 g/L ammonia nitrogen, representing increases of 49 % and 76 %, respectively, compared to reactors without biofilm. Microbial analysis via 16S rRNA sequencing showed that Methanothermobacter, a thermophilic hydrogenotrophic methanogen, increased in relative abundance under ammonia nitrogen stress, which was further supported by carbon isotope analysis. Overall, these results highlighted the potential of AnMBBR to overcome ammonia nitrogen stress in in-situ biomethanation.
Sammendrag
Peat inversion is a management technique used to reduce emissions and retain carbon in cultivated peatland while allowing for effective forage production. Although maps and land registers document the presence of cultivated peatland that is suitable for peat inversion, these data do not cover all regions of interest. This study explores how an expert system and geostatistical modelling can be used to identify cultivated peatland suitable for peat inversion. The expert system proved to work moderately well for cultivable (but not for cultivated) peatland. Geostatistical modelling, using cultivable peatland as statistical support, gave good results in regions with large, continuous landforms. The results were less accurate in regions with rough, rapidly shifting terrain forms and where peatland was less frequent. The difference could be seen in the range and shape of the semivariograms. Geostatistical modelling can be used to identify cultivated peatland suitable for peat inversion in regions where the semivariogram shows a clear and well-defined spatial autocorrelation structure.
Forfattere
Stephan Arnold Geoffrey Smith Geir-Harald Strand Gerard Hazeu Michael Bock Barbara Kosztra Christoph Perger Gebhard Banko Tomas Soukup Nuria Valcarcel Sanz Stefan Kleeschulte Julian Delgado Hernandez Emanuele MancosuSammendrag
The demand for land monitoring information continues to increase, but the range and diversity of the available products to date have made their integrated use challenging and, at times, counterproductive. There has therefore been a growing need to enhance and harmonise the practice of land monitoring on a pan-European level with the formulation of a more consistent and standardised set of modelling criteria. The outcome has been a paradigm shift away from a “paper map”-based world where features are given a single, fixed label to one where features have a rich characterisation which is more informative, flexible and powerful. The approach allows the characteristics to be dynamic so that, over time, a feature may only change part of its description (i.e., a forest can be felled, but it may remain as forestry if replanted) or it can have multiple descriptors (i.e., a forest may be used for both timber production and recreation). The concept proposed by the authors has evolved since 2008 from first drafts to a comprehensive and powerful tool adopted by the European Union’s Copernicus programme. It provides for the semantic decomposition of existing nomenclatures, as well as supports a descriptive approach to the mapping of all landscape features in a flexible and object-oriented manner. In this way, the key move away from classification towards the characterisation of the Earth’s surface represents a novel and innovate approach to handling complex land surface information more suited to the age of distributed databases, cloud computing and object-oriented data modelling. In this paper, the motivation for and technical approach of the EAGLE concept with its matrix and UML model implementation are explained. This is followed by an update of the latest developments and the presentation of a number of experimental and operational use cases at national and European levels, and it then concludes with thoughts on the future outlook.
Sammendrag
Tidleg vårgjødsling ga større engavling og betre utnytting av vekstsesongen, men det kravde meir kraftfôr på grunn av dårlegare grovfôrkvalitet. Ved nok areal var normal vårgjødsling og tidleg førsteslått meir fordelaktig
Forfattere
Ya-Lan Hong Wei-Ming Xi Ya-Ting Wang Yi Yuan Zong-Zhuan Shen Ming Tian Jihong Liu Clarke Wang-Ying Xie Fang-jie ZhaoSammendrag
Environmental transmission of antibiotic resistance poses a significant threat to human health by undermining the efficacy of therapeutic interventions against bacterial infections. Agricultural practices, particularly the application of organic fertilizers derived from animal manure, are major contributors to the spread of antibiotic resistance determinants (ARDs) in soil ecosystems. However, the fates of ARDs and their bacterial hosts in soil following organic fertilization as well as the impact of water management regimes remain poorly understood. We investigated the attenuation and persistence of ARDs in soil following organic fertilization under water management practices of upland, continuous flooding, and intermittent flooding. Most ARDs introduced via the organic fertilizer exhibited significant attenuation, with half-lives ranging from 19 to 50 days, primarily due to the decline of fertilizer-derived bacterial hosts. Specific ARDs, such as aph(3’)-IIIa and tetO, persisted across all treatments. Upland conditions accelerated the attenuation of ARDs and their pathogenic hosts compared to f looding conditions, which prolonged their survival and promoted horizontal gene transfer. The divergent responses of ARD composition and soil bacterial communities to the environmental variables revealed a unique dissemination pattern, wherein the soil co-occurring bacterial communities served as critical hubs for the dissemination of ARDs and their bacterial hosts from organic fertilizers. The soil co-occurring bacterial communities exhibited strong interspecies interactions and high sensitivity to environmental changes. Targeted strategies to disrupt these assembly hubs may provide an effective way to mitigate the spread of antibiotic resistance from organic fertilizers to soil ecosystems.
Sammendrag
Wood modification by impregnation with phenol-formaldehyde (PF) resins is a promising method to improve the woods’ fungal decay resistance, weathering resistance, and dimensional stability. Recent research indicates that 30% of the non-renewable phenol may be substituted by renewable softwood kraft lignin cleavage products obtained through microwave-assisted pyrolysis. Pinus sylvestris sapwood modified with this resin has good fungal decay resistance but slightly enhanced formaldehyde emission. While these results on solid wood indicate a high potential of the method, the properties of modified plywood may differ, and the weathering resistance has not been studied. In this study, formaldehyde emission, weathering resistance and fungal decay resistance against three basidiomycetes (Trametes versicolor, Rhodonia placenta, and Gloeophyllum trabeum) of plywood modified with pure PF resin and PF resin with 30% substitution of the phenol by lignin cleavage products were analysed. The 30% lignin cleavage product substitution didn’t affect the plywood’s fungal decay resistance, with less than 1% initial mass loss in all modified specimens. While the decay resistance improved significantly for all modified samples compared to reference samples, weathering resistance slightly declined with phenol substitution compared to pure PF resin modification. The formaldehyde emissions of the plywood modified with both resins were in similar ranges to that of unmodified reference plywood. Overall, plywood with good properties for exterior applications may be produced even with the substitution of 30% of the phenol by lignin cleavage products, allowing for increased use of renewable resources.
Sammendrag
Diptera larvae and Nematoda were extracted from soil samples collected in the foreland of the receding Hardangerjøkulen glacier near Finse, central south Norway. Samples were standardized by being taken in snowbed habitats with Salix herbacea L. vegetation. Diptera larvae were sampled in twenty plots from 32 to 227 years age, complemented by five plots with about 10,000-year-old soil. Nematodes were studied in soils of 4, 37, 39, 62, 78, 119, and 204 years age. There was a rapid colonization in young soils of both Diptera larvae and nematodes. Brachycera larvae were sparsely represented, and Sciaridae and Chironomidae larvae were most numerous in soils younger than 50 years. Genera of Chironomidae larvae were Bryophaenocladius, Pseudosmittia, Parasmittia, and Smittia. The number of nematode taxa increased from six in the youngest soil to fourteen in the oldest. Bacterial feeders were dominated by the genus Rhabditis sensu lato and fungal feeders by Tylenchus sensu lato. The plant-parasitic Paratylenchus sp. was present at 4 years, with highest abundance at 39 years. The abundance of omnivores (subfamily Dorylaiminae) did not vary between soil ages, but predators (fam. Mononchidae and genus Tripyla) were more abundant at 78 and 119 years.