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
Anders Lorentzen Kolstad Joachim Paul Töpper Marianne Evju Line Johansen Magni Olsen Kyrkjeeide Anders Lyngstad Jan Ketil Rød Lise Tingstad Liv Guri VelleSammendrag
Det er ikke registrert sammendrag
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
Tatiana Francischinelli Rittl Reidun Pommeresche Anders Johansen Håvard Steinshamn Hugh Riley Anne-Kristin LøesSammendrag
Anaerobic digestion (AD) of animal manure generates renewable energy in the form of biogas. However, there is a gap in our understanding of the long-term impacts of AD-treated manure on soil attributes and crop productivity in comparison to untreated manure. To address this, a longterm field experiment was initiated in 2011 within a perennial grass-clover ley. The objective was to investigate the effects on key soil and crop parameters when slurry from organically managed dairy cows underwent AD. The results (2011-2021) indicated that while the application rate of manures influenced soil nutrient levels and pH, these parameters were unaffected by AD treatment. Higher slurry application rate (220 kg of total N ha-1year-1) led to a surplus of N, while deficits were observed in the untreated (non digested) control and the treatments with low application rates (110 kg of total N ha-1year1). Treatments were not limited by P. For K, there were deficitsin all treatments. Soil organic matter (SOM) concentrations decreased across all plots, especially in those with inherently high SOM levels. This decline in SOM was similar with both untreated (non-digested) slurry and anaerobically digested slurry, and there was no significant effect of application rate. The decline may be attributed to the initial high SOM content, prolonged drainage, and increasing temperatures due to climate change. Notably, both US and ADS demonstrated similar yields of grass-clover ley (2 cuts year-1) and green fodder, averaging 7.9 and 4.0 kg DM ha-1, respectively. Additionally, within the same production year the mean clover yields of the fertilized treatments did not differ from the control. In terms of crop yields and chemical soil characteristics, the long-term effects (over 10 years) of AD within an organic dairy cattle farming system were generally minor. The advantages of harvesting energy from slurry did not compromise the long-term productivity of grasslands or the soil chemical characteristics
Forfattere
Tatiana Francischinelli Rittl Lied, Geirmund Aker, Mari Ingvar Kvande Eva Brod Kari-Anne Kallerud LyngSammendrag
The access to marine residual resources is large in Norway, yet its use in agriculture remains limited. Circulizer project aims to improve the circularity between the blue and green sector, by increasing the knowledge of the use of marine residues (i.e. fish sludge and fish silage) for biogas production and its effects on the fertilizer quality (digestate) and environment. While the quality of digestate from food waste and animal manure has been extensively studied, the impact of incorporating increasing proportions of new marine residual resources remains to be investigated. To be able to substitute mineral fertilizer with digestate derived from marine residues, farmers require knowledge of its nutrient composition and availability. In contrast, biogas plant operators need assurance of a market for both biogas and digestate before investing in new facilities. Circulizer will run lab and field scale experiments where the biogas process performance and digestate quality will be assessed. Expected outcomes are: (i) Enhancing the green transition and circularity of Norwegian food production by recycling valuable nutrients from fish production for agricultural use; (ii) Ensuring environmental safety by addressing concerns related to heavy metals and organic pollutants; (iii) Increasing the utilization of marine residual resources for biogas production; (iv) Supporting the growth of the fish farming industry in Norway by improving waste treatment and recycling options for unavoidable residual resources, thereby facilitating increased fish production and nutrient recycling
Forfattere
Maria Åsnes MoanSammendrag
Bonitet er definert som overhøyden ved en gitt referansealder og brukes for å beskrive skogens potensial for å produsere tømmer. Bonitering, altså å bestemme boniteten, har utviklet seg fra feltbaserte metoder til metoder som benytter seg av punktskydata. Punktskydata fra flybåren laserskanning og bildematching har blitt brukt til å bonitere med den direkte og høydedifferensielle metoden. Disse metodene bruker overhøydeutviklingen over en kjent periode til å bonitere ved bruk av punktskydata fra minst to tidspunkt, dvs. multitemporale punktskydata. Den direkte metoden boniterer ved bruk av en prediksjonsmodell for bonitet med forklaringsvariabler beregnet fra punktskydata. Den høydedifferensielle metoden finner boniteten der forventet overhøydeutvikling passer best med den predikerte overhøydeutviklingen. Denne avhandlingen tok sikte på å forbedre metodene for bonitering med punktskydata og består av fire studier. Forstyrrelser kan gjøre et område uegnet for bonitering med punktskydata. Tidligere har man definert egnethet som områder uten negativ utvikling i overhøyde eller biomasse, men dette betyr ikke nødvendigvis at overhøydeutviklingen er uforstyrret. Den første studien i denne avhandlingen klassifiserte egnethet med variabler fra multitemporale laserdata. Egnethet var definert basert på feltregistrerte forstyrrelser hos dominerende trær. Resultatene viste at egnethet kunne klassifiseres med multitemporale laserdata, selv om definisjonene av egnethet i den studien var konservative ettersom ett dødt dominerende tre var nok til at prøveflaten ble klassifisert som uegnet. En tidsserie med laserdata kan forbedre nøyaktigheten til boniteringen sammenlignet med å bruke laserdata fra to påfølgende laserskanninger. Dette er fordi overhøydeutviklingen for en lengre periode vil bli representert. Den andre studien i denne avhandlingen brukte laserdata fra tre tidspunkt for å bonitere med den direkte og høydedifferensielle metoden. Prediksjonsfeilene var ikke statistisk signifikant forskjellig når man brukte laserdata fra hele tidsserien sammenlignet med å bruke laserdata fra to påfølgende tidspunkt, dvs. enten første og andre eller andre og tredje tidspunkt. Imidlertid økte andelen av området som var egnet for bonitering når hvilket som helst delsett av påfølgende tidspunkter i tidsserien kunne brukes, noe som ga en økt fleksibilitet til å unngå å perioder der det hadde vært en forstyrrelse. «Value of improved information» kan brukes til å vurdere nytteverdien av forskjellige boniteringsmetoder når beslutningstakeren har ulike mål for skogforvaltningen. Den tredje studien brukte stokastisk programmering for å beregne «value of improved information» ved bruk av den direkte og høydedifferensielle metoden med enten multitemporale laserdata eller laserdata og påfølgende bildematchingsdata. Resultatene viste at «value of improved information» var nærmest null og dermed best for den høydedifferensielle metoden i vårt studieområde. Den høydedifferensielle metoden kan potensielt brukes til å bonitere i ungskog. Den fjerde studien detekterte posisjonen til kvistkranser fra veldig tette punktskydata med en dyplæringsmodell og brukte detekterte kvistkranser til å bonitere med den høydedifferensielle metoden. Dette ga en «root mean square error» mellom 19,85 og 20,87%. En utfordring med bonitering i ungskog er at bonitetskurvene er brattere for lave aldre sammenlignet med høyere aldre, noe som resulterer i at feil i deteksjonen av kvistkranser har større konsekvenser for bestemmelsen av bonitet i ungskog. Denne avhandlingen har tatt for seg noen utfordringer og muligheter for bonitering med punktskydata. Likevel viste den første og fjerde studien at det er behov for mer forskning på hvordan man best kan definere egnethet og bonitere i ungskog.