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
Mostafa Hoseini Helle Ross Gobakken Stephan Hoffmann Csongor Horvath Johannes Rahlf Jan Bjerketvedt Stefano Puliti Rasmus AstrupSammendrag
RoadSens is a platform designed to expedite the digitalization process of forest roads, a cornerstone of efficient forest operations and management. We incorporate stereo-vision spatial mapping and deep-learning image segmentation to extract, measure, and analyze various geometric features of the roads. The features are precisely georeferenced by fusing post-processing results of an integrated global navigation satellite system (GNSS) module and odometric localization data obtained from the stereo camera. The first version of RoadSens, RSv1, provides measurements of longitudinal slope, horizontal/vertical radius of curvature and various cross-sectional parameters, e.g., visible road width, centerline/midpoint positions, left and right sidefall slopes, and the depth and distance of visible ditches from the road’s edges. The potential of RSv1 is demonstrated and validated through its application to two road segments in southern Norway. The results highlight a promising performance. The trained image segmentation model detects the road surface with the precision and recall values of 96.8 and 81.9 , respectively. The measurements of visible road width indicate sub-decimeter level inter-consistency and 0.38 m median accuracy. The cross-section profiles over the road surface show 0.87 correlation and 9.8 cm root mean squared error (RMSE) against ground truth. The RSv1’s georeferenced road midpoints exhibit an overall accuracy of 21.6 cm in horizontal direction. The GNSS height measurements, which are used to derive longitudinal slope and vertical curvature exhibit an average error of 5.7 cm compared to ground truth. The study also identifies and discusses the limitations and issues of RSv1, which provide useful insights into the challenges in future versions.
Forfattere
Rasmus Bang Stine Samsonstuen Bjørn Gunnar Hansen Mario Guajardo Hanne Møller Jon Kristian Sommerseth Julio C. Goez Ola FlatenSammendrag
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.
Sammendrag
Optimised contributions of green infrastructure (GI) to urban ecosystem services are strongly related to its multifunctionality. The challenge, however, is that the concept of multifunctionality still needs to be transformed into an operationalised assessment to evaluate current performance, which is instrumental in supporting spatial planning and policy strategies. Using the case of Stavanger City (Norway), the study conducted a spatial assessment of the multifunctionality of the urban green infrastructure. The study used a comprehensive set of 27 function indicators estimated for each of the 156 spatial units classified by their type, age, size, and biophysical characteristics. Correlation patterns among indicators and how the average and effective multifunctionality related to unit characteristics were analysed using correlation and multivariate approaches. The study demonstrated weak correlations between function indicators but revealed some potential trade-offs and function bundles. Notably, bundles related to tree cover (e.g. C sequestration, stormwater retention) had negative relationships with facilitation measures. There was a large overlap in functions between GI types associated with public green spaces and parks. Moreover, the characteristics of green infrastructure units, like size and age, primarily affected multifunctionality through effects on function indicators. Regarding the city-wide multifunctionality, we found some turnover and subsetting of functions among units, supporting multifunctionality at larger spatial scales. However, the average contributions from different GI types were similar. The study highlights the need to understand correlation patterns among function indicators and function bundles as critical to benefit from synergies and avoid unintentional trade-offs when designing and managing urban green areas.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Jian Liu Faruk Djodjic Barbro Ulén Helena Aronsson Marianne Bechmann Lars Bergström Tore Krogstad Katarina KyllmarSammendrag
Det er ikke registrert sammendrag
Sammendrag
Informasjon om frøavl av engknoppurt, svartknoppurt og fagerknoppurt
2024
Forfattere
Helene Leirset TysdalSammendrag
In a world with war, hunger and increasing expenses, food production is an important aspect. Every country has a need and a responcibility to be able to produce enough food for its own people. Wheat is an important crop that can contribute to increased self sufficiency in Norway. The Norwegian milling industry largely controls the proportion of domestic wheat to be used for milling. Because of that they have imported a lot of the wheat needed to produce flour in the past. In the cases where Norwegian wheat have been used, it has mostly been spring wheat. Winter wheat has a high yield potential, and can ve important to utilize to achive goals for increased self-sufficienct fot the Norwegian agriculture, but more research is required to meet the milling industries requirements. Winter wheat production may be an important step in this process. This master thesis aimes to reachers how split nitrogen fertilication affects yield components and protein in the grain. As well as how N-sensor measurments at heading and flowering can be an effective tool to guide the farmers. Five fertilization strategies, four locations and tre variaties was used to reachers the effect of split nitrogen fertlization. Each location had three repetitions and every repition included every possible combination of fertilization strategy and variaty. Plant nitrogen level was monitored during the growing season to predict the protein content at harvest. The results showed that for protein percentage, the fertilization regiment is the most important aspect, hereunder total nitrogen content and the distributio between the different applications. Giving 8 kg of nitrogen at the first application and 6 kg of nitrogen at the second application gave a significantly higher protein content compered to giving 14 kg of nitrogen at the first application and nothing at the second. To get a higher yield the most important aspect is the winter wheat variety and Kuban gave a significantly higher yield than Bernstein and Ellvis. N-sensor measurments and measurments of the real nitrogen uptake was done at heading and flowering. The N-sensor measurmetns underestimated the nitrogenuptake especially in field with drought. Regression analysis found that 2/3 of the observed variation could be explained by the model at z49 and z65. More research and a bigger dataset is thereby needed to get a better model.
Forfattere
Erlend Podhorny ØklandSammendrag
Denne masteroppgaven består av en teoridel og en forsøksdel med egne undersøkelser. Teoridelen tar for seg temaer relatert til grovfôr og drøvtyggerernæring. Grovfôr består av ulike fraksjoner, deriblant strukturelle karbohydrater som hemicellulose og cellulose. Disse kan fordøyes av drøvtyggere gjennom fermentering i formagene, hvor mikrober bryter karbohydratene ned til flyktige fettsyrer. Grovfôr kan konserveres gjennom ensilering, hvor melkesyrebakterier fermenterer sukker i graset til melkesyre, som senker pH og gjør fôret lagringsstabilt. For å øke sannsynligheten for vellykket ensilering kan ensileringsmidler tilsettes, deriblant fibrolytiske enzymer som bryter ned hemicellulose og cellulose. Målet med fibrolytiske enzymer er å frigjøre sukker til melkesyrebakterier, i tillegg til å øke fordøyeligheten av grovfôret. Forsøksdelen er utformet som en artikkel, hvor formålet var å undersøke effekten av maursyre og fibrolytiske enzymer på fordøyelighet av ensilert gras. Timotei (Phleum pratense) ble høstet ved et sent utviklingstrinn og behandlet med maursyre og/eller enzymer før ensilering. Enzymene som ble testet var hemicellulase, cellulase, Cellic CTec2 og laccase. Etter ensilering ble fordøyelighet av tørrstoff (TS), organisk stoff (OS) og nøytralløselig fiber (NDF) undersøkt med ANKOM DaisyII inkubator. Fordøyelighet av NDF ble beregnet både som tap av native NDF (NDF som er analysert for hver enkel behandling) og som tap av totalt NDF basert på ubehandlet surfôr (“originalt” innhold av NDF i ubehandlet surfôr ble brukt som basis for forsvinningsgrad) for å ta hensyn til NDF som ble nedbrutt under ensilering. Innhold av NDF var signifikant (p<0.05) lavere for behandlinger med enzymer, enn behandlinger uten enzymer. Selv om maursyre ikke reduserte NDF signifikant, var det nær en trend (p=0.1003). Fordøyelighet av TS og OS økte signifikant (p<0.05) både ved bruk av enzymer og maursyre. Enzymer reduserte den potensielt nedbrytbare fraksjonen av TS og OS og økte den løselige fraksjonen, begge signifikant (p<0.05). Fordøyelighet av native NDF ble redusert (p<0.05) ved bruk av enzymer, men fordøyelighet av total NDF ble økt (p<0.05). Maursyre reduserte ufordøyelig NDF signifikant (p<0.05) for native NDF og total NDF sammenlignet med hvis maursyre ikke ble brukt. Forsøket som helhet bekreftet hypotesen om at bruk av enzymer og maursyre kan øke fordøyeligheten av grovfôr.
Forfattere
Emma SkogstadSammendrag
In cereal production plant pathogens cause yield losses, and management strategies for controlling them are important. Cover crops as a part of the cereal production have beneficial properties for the soil health, can increase the biological diversity in the fields, and the soil structure can be improved, additionally cover crops can reduce soil erosion. Therefore, this thesis argues that implementing cruciferous plants as part of the cover crops have the potential to reduce plant pathogens. Cruciferous plants used as cover crops have shown to reduce plant pathogens survival both in laboratory and field plots. The suppression is due to the volatile glucosinolate (GLS) and isothiocyanate (ITC) content cruciferous plants. As a part of a project at NIBIO Ås, an in vitro experiment with allyl ITC were done to look at the effect on survival of Heterodera avenae, Fusarium graminearum and Microdochium nivale, with increasing allyl ITC concentration. Also, a closed jar experiment was conducted to look at the effects of cruciferous plants on suppression of survival of Heterodera avenae and Fusarium graminearum. The aim of the in vitro experiment was to see at which concentrations of allyl ITC that suppressed fungal growth of F. graminearum and M. nivale and hatching of the cereal cyst nematode H. avenae. The EC50-values of the F. graminearum isolates 200 630, 201 196 and 202 058, were 6.36, 9.50 and 7.62 mg/L respectively. EC50-values of M. nivale isolates 200 136, 200 231 and 202 786, were 8.60, 10.83 and 10.27 mg/L respectively. For H. avenae, the EC50-value was at 5.66 mg/L. This demonstrates a differentiation of EC50-values between nematodes and fungi, but also between fungal species and fungal isolates. A closed jar experiment was conducted to see if incorporation of cruciferous plants in soil may affect the survival of H. avenae and F. graminearum. Two different time exposures in jars with either two or eight weeks of exposure in jars, were performed. After treatments in jars, the cysts were given either a diapause or no diapause treatment. The total number of eggs and J2 were significantly lower for cysts exposed for eight weeks in jars compared to two weeks, but the total number of eggs and J2 were almost equal for diapause and no diapause. The number of hatched J2 (15°C) for cysts with diapause treatment had significantly higher number of J2 than no diapause treatment. Also, the number of hatched J2 were significantly higher for two weeks exposure in jars compared to eight weeks. The mycelial growth from F. graminearum on oat spikelet incorporated in soil with plant material was not different from untreated.
Forfattere
Maria KorkouSammendrag
PhD thesis in City and regional planning