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.
2023
Sammendrag
Cover crops are used to increase carbon sequestration in soils. However, an increase of organic matter in soils not only increases carbon stocks but also affects nitrogen availability. This can trigger N2O emissions, particularly during wintertime, when standing plant biomass from cover crops decays. N2O emissions associated with cover crops could potentially cancel out the carbon gain. In this study, N2O emissions were measured over two years in a field experiment in SE Norway with barley and various cover crops (perennial and Italian ryegrass, oilseed radish, summer and winter vetch, phacelia and a mixture of different herbs) and compared with controls without cover crops. Manual chambers were used in summer during the growth of the main crop, while winter emissions were measured more frequently by a field robot to capture freeze-thaw induced emission peaks. Both winters had poor snow cover and the highest N2O emissions were measured during freeze-thaw cycles in early spring. Nitrogen-rich cover crops with poor overwintering (oilseed radish) increased wintertime emissions, whereas perennial cover crops with good overwintering (perennial ryegrass and herb mixture) tended to reduce N2O emissions compared to controls. This suggests that the overall climate effect of cover crops in hemiboreal cereal production depends on cover crop species and winter conditions.
Sammendrag
We tested whether windthrow damage to Nordic conifer forest stands could be reliably detected as canopy height decrease between a pre-storm LiDAR (Light Detection and Ranging) digital surface model (DSM) and a photogrammetric DSM derived from a post-storm WorldView-3 stereo pair. The post-storm ground reference data consisted of field and unmanned aerial vehicle (UAV) observations of windthrow combined with no-damage areas collected by visual interpretation of the available very high resolution (VHR) satellite imagery. We trained and tested a thresholding model using canopy height change as the sole predictor. We undertook a two-step accuracy assessment by (1) running k-fold cross-validation on the ground reference dataset and examining the effect of the potential imperfections in the ground reference data, and (2) conducting rigorous accuracy assessment of the classified map of the study area using an extended set of VHR imagery. The thresholding model produced accurate windthrow maps in dense, productive forest stands with a sensitivity of 96%, specificity of 71%, and Matthews correlation coefficient (MCC) over 0.7. However, in sparse and high elevation stands, the classification accuracy was poor. Despite certain collection challenges during the winter months in the Nordic region, we consider VHR stereo satellite imagery to be a viable source of forest canopy height information and sufficiently accurate to map windthrow disturbance in forest stands of high to moderate density.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Datamodellen WISPE ble ferdigutviklet i 2013 for å kunne undersøke avrenning og utlekking av plantevernmidler i miljøet under norske forhold. Formålet med dette prosjektet har bl.a. vært å oppdatere WISPE-modellen og gjøre den enda mer brukervennlig. Modellverktøyet WISPE er videreutviklet blant annet i henhold til oppdateringer anbefalt for EU-modeller av det såkalte FOCUSRepair- prosjektet. Mulighet for å kunne estimere effekten av vegetasjonssoner med ulik bredde er også lagt inn. Modellen er endret slik at det er blitt enklere å videreutvikle verktøyet og legge til nye data uten bruk av programmeringseksperter samt at det er enkelt å kjøre modellen med forskjellige klimafiler for å se på effekten av klimaendringer. Det er utviklet en brukermanual som skal gjøre det lettere å bruke modellen, både for forvaltning, industri og innen forskningen. Waterborne Environmental har stått for programmering og all teknisk utvikling i dette prosjektet. NIBIO har bidratt med data og kunnskap om norske forhold samt testing og innspill underveis. Waterborne har innhentet innspill fra plantevernmiddelindustrien samt utviklere i Europa som jobber med EUmodellene. Resultatene fra prosjektet er formidlet på ulike internasjonale konferanser og i et eget møte med Mattilsynet og en representant fra industrien (Bayer CropScience). Hovedleveransen fra prosjektet er det oppdaterte modellverktøyet og brukermanualen. Informasjon om modellen, brukermanualen og selve modellen gjøres tilgjengelig på NIBIOs nettsider i løpet av våren 2023.
Sammendrag
There is an increased interest in the hydroponic production of strawberries in protected cultivation systems, and it is, therefore, urgent to develop new, more sustainable growing media alternatives. This study investigated the physical properties of wood fiber produced from Norway spruce (Picea abies (L.) H. Karst.) and peat:wood fiber substrate blends as well as the performance of the wood fiber in comparison to the industry standards, i.e., peat and coconut coir in the cultivation of hydroponic strawberry. Tray plants of the June-bearing strawberry (Fragaria × ananassa Duch.) cultivar ‘Malling Centenary’ were transplanted into five different growing media: a peat (80%) and perlite (20%) mixture, stand-alone (100%) coconut coir and three stand-alone (100%) Norway spruce wood fiber substrates (including coarse textured fibers with compact and loose packing density and compacted fine-textured fibers). Ripe strawberries were harvested and registered throughout the production season. The overall marketable yield was comparable across all the tested growing media; however, after 4 weeks of harvest, both coarse wood fiber and fine wood fiber showed better fruiting performance than the peat-perlite mixture. A trend for earlier berry maturation was observed for all wood fiber-based substrates. Plant parameters recorded after the end of production showed that plant height, number of leaves, and biomass production were higher in coarse wood fiber than in the peat-perlite mixture. Moreover, plants grown in wood fiber-based substrates had less unripe berries and flowers not harvested in comparison to both the peat and coir treatments.
Forfattere
Siv Mari Aurdal Tomasz Leszek Woznicki Trond Haraldsen Krzysztof Kusnierek Anita Sønsteby Siv Fagertun RembergSammendrag
Cultivation of strawberries in greenhouses and polytunnels is increasing, and new sustainable growing media are needed to replace peat and coconut coir. This study investigated the effect of wood fiber and compost as growing media on hydroponically cultivated strawberries. Two experiments were conducted, where the everbearing cultivar ‘Murano’ was grown in mixtures of wood fiber and compost (Experiment 1) and the seasonal flowering cultivar ‘Malling Centenary’ was grown in mixtures of wood fiber and peat (Experiment 2). Additionally, in Experiment 2, the effect of adding start fertilizer was assessed. The yield potential of ‘Murano’ plants was maintained in all substrates compared to the coconut coir control. However, a mixture of 75% wood fiber and 25% compost produced the highest yield, suggesting that mixtures of nutritious materials with wood fiber may improve plant performance. The chemical composition of the berries was not affected by the substrate composition; however, berries from plants grown in the best performing blend had a lower firmness than those grown in coconut coir. ‘Malling Centenary’ plants produced higher yields in substrates enriched with start fertilizer. Generally, the productivity of ‘Malling Centenary’ plants was maintained in blends containing up to 75% of wood fiber mixture even without start fertilizer.
Forfattere
Jian LiuSammendrag
Det er ikke registrert sammendrag
Forfattere
Divina Gracia P. RodriguezSammendrag
Det er ikke registrert sammendrag
Forfattere
Divina Gracia P. RodriguezSammendrag
Det er ikke registrert sammendrag
Forfattere
Kristoffer Herland Hellton Helga Amdahl Thordis Thorarinsdottir Muath K Alsheikh Trygve S. Aamlid Marit Jørgensen Sigridur Dalmannsdottir Odd Arne RognliSammendrag
The perennial forage grass timothy (Phleum pratense L.) is the most important forage crop in Norway. Future changes in the climate will affect growing conditions and hence the yield output. We used data from the Norwegian Value for Cultivation and Use testing to find a statistical prediction model for total dry matter yield (DMY) based on agro-climatic variables. The statistical model selection found that the predictors with the highest predictive power were growing degree days (GDD) in July and the number of days with rain (>1mm) in June–July. These predictors together explained 43% of the variability in total DMY. Further, the prediction model was combined with a range of climate ensembles (RCP4.5) to project DMY of timothy for the decades 2050–2059 and 2090–2099 at 8 locations in Norway. Our projections forecast that DMY of today’s timothy varieties may decrease substantially in South-Eastern Norway, but increase in Northern Norway, by the middle of the century, due to increased temperatures and changing precipitation patterns.