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.
2018
Forfattere
Kris Verheyen Martin Bažány Ewa Chećko Markéta Chudomelová Déborah Closset-Kopp Patryk Czortek Guillaume Decocq Pieter De Frenne Luc De Keersmaeker Cecilia Enriquez Garcia Martina Fabšičová John-Arvid Grytnes Lucia Hederová Radim Hédl Thilo Heinken Fride Høistad Schei Soma Horváth Bogdan Jaroszewicz Edyta Jermakowicz Terezá Klinerova Jens Kolk Martin Kopecký Iwona Kuras Jonathan Lenoir Martin Macek František Máliš Tone Constance Martinessen Tobias Naaf László Papp Ágnes Papp-Szákaly Paweł Pech Petr Petřík Jindřich Prach Kamila Reczýnska Magne Sætersdal Fabien Spicher Tibor Standovár Krzysztof Świerkosz Ewa Szczęśniak Zoltán Tóth Karol Ujházy Mariana Ujházyová Pieter Vangansbeke Ondřej Vild Dan Wołkowycki Monika Wulf Lander BaetenSammendrag
Aim: Revisits of non-permanent, relocatable plots first surveyed several decades ago offer a direct way to observe vegetation change and form a unique and increasingly used source of information for global change research. Despite the important insights that can be obtained from resurveying these quasi-permanent vegetation plots, their use is prone to both observer and relocation errors. Studying the combined effects of both error types is important since they will play out together in practice and it is yet unknown to what extent observed vegetation changes are influenced by these errors. Methods: We designed a study that mimicked all steps in a resurvey study and that allowed determination of the magnitude of observer errors only vs the joint observer and relocation errors. Communities of vascular plants growing in the understorey of temperate forests were selected as study system. Ten regions in Europe were covered to explore generality across contexts and 50 observers were involved, which deliberately differed in their experience in making vegetation records. Results: The mean geographic distance between plots in the observer+relocation error data set was 24 m. The mean relative difference in species richness in the observer error and the observer+relocation data set was 15% and 21%, respectively. The mean “pseudo-turnover” between the five records at a quasi-permanent plot location was on average 0.21 and 0.35 for the observer error and observer+relocation error data sets, respectively. More detailed analyses of the compositional variation showed that the nestedness and turnover components were of equal importance in the observer data set, whereas turnover was much more important than nestedness in the observer+relocation data set. Interestingly, the differences between the observer and the observer+relocation data sets largely disappeared when looking at temporal change: both the changes in species richness and species composition over time were very similar in these data sets. Conclusions: Our results demonstrate that observer and relocation errors are nonnegligible when resurveying quasi-permanent plots. A careful interpretation of the results of resurvey studies is warranted, especially when changes are assessed based on a low number of plots. We conclude by listing measures that should be taken to maximally increase the precision and the strength of the inferences drawn from vegetation resurveys.
Forfattere
Audun KorsæthSammendrag
Dette prosjektet er i sin helhet finansiert av Opland Fylkeskommune, og handler om å bidra til en reduksjon i klimagassutslippene fra jordbruket gjennom å ta et første steg mot en helhetlig løsning med bruk av presisjonsjordbruk og elektriske, til dels selvgående traktorer/roboter. Prosjektet er utført i felleskap av NIBIO og IFE, med ulike bidrag fra samarbeidsaktørene Yara Norge, Felleskjøpet Agri SA, Norges Bondelag, Norsk Landbruksrådgivning, Gjøvikregionen utvikling og Mat fra Toten. Ca. 360 m2 med solcellepaneler ble installert på et låvetak på Apelsvoll (Senter for presisjonsjordbruk) som en del av egeninnsatsen til NIBIO i prosjektet. IFEs arbeid i prosjektet, innebar bl.a. å installere et system for overvåkning/monitorering av solinnstrålingen og av selve solcelleanlegget. Videre ble ulike alternativer for batteri og styringssystemer analysert, og det ble arbeidet med en modell for optimal dimensjonering og design av systemet utviklet i TRNSYS (for mer detaljer, se egen delrapport fra IFE, vedlegg 1). NIBIOs del av prosjektet handlet om å utvikle et helhetlig system for informasjonsinnhenting (scouting), signalbearbeiding, variabel rateteknologi og kommunikasjons- og styresystemer som muliggjør at flere til dels autonome farkoster løser agronomiske utfordringer i fellesskap. Helt konkret har vi videreutviklet to UAVer; et multikopter og et hybrid fly/helikopter i prosjektet. Dessuten har vi anskaffet og videreutviklet en selvgående, elektrisk robot-traktor, og utviklet en tilhørende prototyp for eksaktgjødsling med flytende gjødsel. Arbeidet med design og utvikling av en ladestasjon har kommet et godt stykke på veg, men er ikke avsluttet. Det samme gjelder arbeidet med kommunikasjons- og styresystemene (begge oppgaver videreføres i et oppfølgingsprosjekt; se under). Dette prosjektet beredt grunnen for og finansiert søknadsprosessen knyttet opp til et større oppfølgingsprosjekt: «SolarFarm – En systemstudie av hvordan solstrøm produsert på gårdsnivå kan drive elektriske og delvis selvstyrte farkoster i et presisjonsjordbruk med reduserte utslipp av klimagasser». Dette forskningsprosjektet som er finansiert over Norges Forskningsråd sitt program «Lavutslipp 2030» (samlet bevilgning på NOK 20,5 mill.), er dermed på mange måter et resultat av prosjektet «Fra sol til bord». Sist, men ikke minst, har formidling utgjort en viktig del av dette prosjektet. Til formidlingen har vi bl.a. benyttet egne nettsider, og vi har hatt omfattende aktivitet i forbindelse med eksterne konferanser/workshops/møter i inn- og utland, og i form av presentasjoner og demonstrasjoner for besøkende som har kommet til Senter for presisjonsjordbruk. Oppsummert har det vært 4 presentasjoner på internasjonale konferanser, seminar og workshops, 46 presentasjoner og demonstrasjoner i Norge, og 8 presseoppslag (for en komplett oversikt, se Appendix).
Forfattere
Bernardo Duarte Irene Martins Rui Rosa Ana R. Matos Michael Roleda Thorsten B. H. Reusch Aschwin H. Engelen Ester A. Serrão Gareth A. Pearson João C. Marques Isabel Caçador Carlos M. Duarte Alexander Oliver JüterbockSammendrag
Marine macrophytes are the foundation of algal forests and seagrass meadows–some of the most productive and diverse coastal marine ecosystems on the planet. These ecosystems provide nursery grounds and food for fish and invertebrates, coastline protection from erosion, carbon sequestration, and nutrient fixation. For marine macrophytes, temperature is generally the most important range limiting factor, and ocean warming is considered the most severe threat among global climate change factors. Ocean warming induced losses of dominant macrophytes along their equatorial range edges, as well as range extensions into polar regions, are predicted and already documented. While adaptive evolution based on genetic change is considered too slow to keep pace with the increasing rate of anthropogenic environmental changes, rapid adaptation may come about through a set of non-genetic mechanisms involving the functional composition of the associated microbiome, as well as epigenetic modification of the genome and its regulatory effect on gene expression and the activity of transposable elements. While research in terrestrial plants demonstrates that the integration of non-genetic mechanisms provide a more holistic picture of a species’ evolutionary potential, research in marine systems is lagging behind. Here, we aim to review the potential of marine macrophytes to acclimatize and adapt to major climate change effects via intraspecific variation at the genetic, epigenetic, and microbiome levels. All three levels create phenotypic variation that may either enhance fitness within individuals (plasticity) or be subject to selection and ultimately, adaptation. We review three of the most important phenotypic variations in a climate change context, including physiological variation, variation in propagation success, and in herbivore resistance. Integrating different levels of plasticity, and adaptability into ecological models will allow to obtain a more holistic understanding of trait variation and a realistic assessment of the future performance and distribution of marine macrophytes. Such multi-disciplinary approach that integrates various levels of intraspecific variation, and their effect on phenotypic and physiological variation, is of crucial importance for the effective management and conservation of seagrasses and macroalgae under climate change.
Sammendrag
European plums (Prunus domestica L.) blossom abundantly most years and often set too many flowers. If these excessive numbers of fruitlets remain on the trees until harvest, the crop would consist of small, unmarketable fruits of low fruit quality. Thinning agents like ammoniumthiosulphate (ATS), sulphur and soya oil desiccate flowers, especially stigma, which is the most sensitive tissue part of the flower. This way, the main effect of blossom thinning treatments is the disruption of pollination and fertilization. Thinning trials were conducted at a commercial orchard near the shore of the Hardangerfjord near Nibio Ullensvang, western Norway (60.2°N) on mature ‘Jubileum’ trees, all grafted on ‘St. Julien A’ rootstock. The trees were treated with 0.4, 0.8, 2 and 4% sulphur; a mixture of 0.4% sulphur + 2% soya oil and 1.5% ATS (liquid and powder formulations), at full bloom. All treatments were compared with hand-thinned and unthinned trees which were used as a control. Experimental trees were sprayed to the point of run-off with a hand sprayer during May 2008 and 2009 at full bloom. Flower thinners were efficient at relatively low temperatures which is a benefit in a cooler climate. In 2008 all thinning treatments reduced fruit set compared to unthinned controls for all cultivars. Sulphur and soya oil, both alone and in combination, were significantly less effective than ATS. In 2009, fruit set was higher and the effects of all thinning agents were lower. Fruit set decreased with increasing sulphur concentrations, but fruit thinning was not sufficient, even at the highest concentration. Both the liquid and powder formulations of ATS gave the same thinning effects. For all thinning treatments, both significant yield reductions and fruit weight increment were noticed during the experimental period. Fruit over color and soluble solids were generally higher and increased significantly with lower crop load, while fruit firmness (Durofel) and total acidity were less affected. In conclusion, different concentrations of sulphur had a moderate thinning effect and are not recommended for use as plum thinners under these conditions. Instead, 1.5% ATS application, (liquid and powder) applied at full bloom, resulted in adequate thinning of ’Jubileum’ plums under cool mesic northern climatic conditions.
Forfattere
Carrie Joy Andrew Rune Halvorsen Einar Heegaard Thomas W. Kuyper Jacob Heilmann-Clausen Irmgard Krisai-Greilhuber Claus Bässler Simon Egli Alan C. Gange Klaus Høiland Paul M. Kirk Beatrice Senn-Irlet Lynne Boddy Ulf Büntgen Håvard KauserudSammendrag
Aim:Macroecological scales of species compositional trends are well documentedfor a variety of plant and animal groups, but remain sparse for fungi, despite theirecological importance in carbon and nutrient cycling. It is, thus, essential to under-stand the composition of fungal assemblages across broad geographical scales andthe underlying drivers. Our overall aim was to describe these patterns for fungiacross two nutritional modes (saprotrophic and ectomycorrhizal). Furthermore, weaimed to elucidate the temporal component of fruiting patterns and to relate theseto soil carbon and nitrogen deposition. Location:Central and Northern Europe.Methods:A total of 4.9 million fungal fruit body observations throughout Europe,collected between 1970 and 2010, were analysed to determine the two main envi-ronmental and geographical gradients structuring fungal assemblages for two mainnutritional modes, saprotrophic and ectomycorrhizal fungi. Results:Two main gradients explaining the geography of compositional patternswere identified, for each nutritional mode. Mean annual temperature (and relatedcollinear, seasonal measures) correlated most strongly with the first gradient forboth nutritional modes. Soil organic carbon was the highest correlate of the second compositional gradient for ectomycorrhizal fungi, suspected as an indicator of vege-tation- and pH-related covariates. In contrast, nitrogen deposition constituted asecond gradient for saprotrophic fungi, likely a proxy for anthropogenic pollution.Compositional gradients and environmental conditions correlated similarly whenthe data were divided into two time intervals of 1970–1990 and 1991–2010.Evidence of compositional temporal change was highest with increasing elevationand latitude. Main conclusions:Fungal assemblage patterns demonstrate clear biogeographicalpatterns that relate the nutritional modes to their main environmental correlates oftemperature, soil organic carbon and nitrogen deposition. With respect to globalchange impacts, the highest rates of compositional change by time suggest targetinghigher latitudes and elevations for a better understanding of fungal dynamics. We,finally, suggest further examination of the ranges and dispersal abilities of fungi tobetter assess responses to global change.
Forfattere
Hella Ellen Ahrends Werner Eugster Thomas Gaiser Victor Rueda-Ayala H. Hüging F. Ewert Stefan SiebertSammendrag
For highly productive regions such as Germany, the increase of wheat grain yields observed throughout the 20th century is largely attributed to the progress in crop breeding and agronomic management. However, several studies indicate a strong variability of the genetic contribution across locations that further varies with experimental design and variety selection. It is therefore still unclear to which extent management conditions have promoted the realization of the breeding progress in Germany over the last 100+ years. We established a side-by-side cultivation experiment over two seasons(2014/2015 and 2015/2016)including 16 winter wheat varieties released in Germany between 1895 and 2007. The varieties were grown using 24 different long-term fertilization treatments established since 1904 (Dikopshof, Germany). Averaged over all cultivars and treatments mean yields of 6.88 t ha−1 and 5.15 t ha−1were estimated in 2015 and 2016, respectively. A linear mixed effects analysis was performed to study the treatment-specific relation between grain yields and year of variety release. Results indicate a linear increase in grain yields ranging from 0.025 to 0.032 t ha−1 yr−1 (0.304 to 0.387% yr−1 )in plots that were treated with combined synthetic-organic fertilizers without signs of a leveling-off. Yields from low or unfertilized plots do not show a significant progress in yield. Responsiveness of mean yields to fertilizer management increases with year of release and indicates small yield penalties under very low nutrient supply. Results highlight the need to consider the importance of long-term soil fertilization management for the realization of genetic gains and the value of long-term fertilization experiments to study interactions between genetic potential and management.
Forfattere
Trine Aulstad Sogn Ivan Dragicevic Roar Linjordet Tore Krogstad Vincent Eijsink Susanne Eich-GreatorexSammendrag
Purpose The main purposes of the study were to assess the NPK fertilizer value of biogas digestates in different soils and to evaluate the risk of unwanted nutrient leaching. Methods The fertilizer value of digestates from anaerobic digesters was investigated in a greenhouse pot experiment with wheat in three different soils; silt, loam and sand. The digestates were based on different feedstock and had a low, dry matter content. The fertilizing effect of digestates was compared to mineral fertilizer and manure. To investigate the fate of excess nutrients in soil after the growing season, the pots were leached after harvest. A complementary soil column leaching experiment without plants was carried out in the laboratory. Results The concentration of ammonium in digestates provided a good indicator of the nitrogen fertilizer value of the digestates. In the silt and loam, the ammonium N fraction in digestates had a fertilizer replacement value equal to that of mineral fertilizer N, whereas the replacement value was higher in the nutrient poor sandy soil. Digestates often have a ratio between nitrogen, phosphorus and potassium which is not favourable for plant growth. However, the suboptimal balance did not result in reduced plant growth or unwanted leaching from soil. Conclusions The results show that digestates from biogas production based on fundamentally different feedstock are promising as NPK fertilizers. The N fertilization can simply be based on the digestate NH4+ concentration and, at least for wheat production, considerable variation in the concentrations of K and P can be tolerated.
Forfattere
M. Bauer R. Harzer K. Strobl Johannes KollmannSammendrag
River restoration is widely applied, although its effects are poorly understood, and degraded habitats might be difficult to improve. Moreover, there is a lack of monitoring as well as few systematic comparisons of restoration methods. This study presents results of a 4‐year monitoring on River Inn (southern Germany) investigating restoration by gravel or sand addition or embankment removal. The results were compared with reference sites that represent the pre‐restoration conditions. At the landscape scale, we analysed vegetation types based on aerial photographs, whereas at a smaller scale, we undertook vegetation surveys and evaluated species composition, growth, and life form, as well as the proportion of the target vegetation. After 4 years, the data indicated a “negative resilience” of the vegetation back to the state prior to restoration. The structural analysis revealed an extensive spread of reed at expense of bare soil. Thus, the species composition largely regressed to the pre‐restoration conditions, and neither annuals nor other pioneer species showed a long‐term benefit of river restoration. There were differences among the three restoration treatments after 2 years, but no longer after 4 years. However, the river restoration had three positive outcomes: (a) There was a temporary benefit for pioneer vegetation that most likely replenished the seed bank of the respective species, (b) the valuable reed communities showed resilience, and (c) the measures allowed some practical learning as expected for adaptive restoration.
Forfattere
Isaiah Nyagumbo Mehreteab Tesfai Sekhar Udaya Nagothu Peter Setimela James K. Karanja Munyaradzi Mutenje Connie MademboSammendrag
Det er ikke registrert sammendrag
Forfattere
Pauline Bristiel Lauren Gillespie Liv Østrem Jennifer Balachowski Cyrille Violle Florence VolaireSammendrag
1. A core tenet of functional ecology is that the vast phenotypic diversity observed in the plant kingdom could be partly generated by a trade-off between the ability of plants to grow quickly and acquire resources in rich environments vs. the ability to conserve resources and avoid mortality under stress. However, experimental demonstrations remain scarce and potentially blurred by phylogenetic constraints in cross-species analyses. Here, we experimentally decoupled growth potential and stress survival by applying an off-season stress on contrasting populations of the perennial grass Dactylis glomerata exhibiting a range of seasonal dormancy.2. Seventeen populations of D. glomerata, originating from a latitudinal gradient from Norway to Morocco, were subjected to three types of dehydration stress: winter frost in Norway, and summer drought and early spring (off-season) drought stress in the south of France. Growth rate and two leaf traits (leaf width and leaf dry matter content) suspected to be involved in the adaptation to dehydration stress were monitored under optimal conditions. We quantified plant dehydration survival as the amount of plant recovery after a severe stress.3. Nordic populations were found to be winter-dormant. Winter- and summer-dor-mant populations better survived frost and summer drought, respectively. However, no trade-off between growth potential and dehydration survival was detected in non-dormant plants in early spring when dehydration occurred unsea-sonably for all populations. Furthermore, Mediterranean populations better survived an early spring drought.4. Our results highlight the importance of assessing plant growth potential as a re-sponse to seasonal environmental cues. They suggest that growth potential and stress survival trade off when plants exhibit seasonal dormancy but can be func-tionally independent at other seasons. Consequently, the growth–stress survival relationship could be better described as a dynamic linkage rather than a constant and general trade-off. Moreover, leaf trait values, such as thinner and more ligni-fied leaves reflecting drought adaptation, may have contributed to the improved drought-stress survival without resulting in a cost to growth. 5. Further exploration of the growth–stress survival relationship should permit deci-phering the suite of plant traits and trait covariations involved in plants’ responses to increasing stress.