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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2023

Sammendrag

In the economics literature, measuring the performance of a dairy farm with a total productivity index is common practice. Previous research, on the other hand, has been chastised for failing to account for agricultural emissions in their models when calculating resource use productivity. This study estimated green total factor productivity (GTFP) accounting for dairy farms' CH4 emission to the model. The study is based on unbalanced panel data from 692 specialized dairy farms from 1991 to 2020. To estimate GTFP and its components using multiple input–output environmental production technologies, a stochastic input distance function and a Translog model were used. The average annual growth rate of green production over the research period was 0. 032%. The main reason for the increase in GTFP was positive scale change contributions. Technological change (− 0.031% per year) and efficiency change (− 0.002% per year), on the other hand, had a detrimental effect on GTFP.

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Sammendrag

Leys are an important part of northern European livestock production, particularly for ruminants since monogastric animals are limited in their ability to digest the fibres of the forage. Crop fractionation methods are a promising option to make forages more beneficial for monogastric animals and decrease the amount of imported protein feed. A leaf stripping harvesting technique was evaluated at Röbäcksdalen in northern Sweden in mixed grass-clover leys over 2 years. The PremAlfa Mini leaf stripper (Trust'ing-Alf'ing, Nantes, France) worked well in mixed stands, harvesting on average a third of the available forage biomass, primarily in the form of leaves and soft stems from the clover plants. It proved successful in producing a forage fraction that had a significantly higher crude protein (CP) concentration (+39.1%) and lower neutral detergent fibre (aNDFom) concentration (−21.4%) than the pre-harvest mixed sward (all significant at p < .05 level). Due to the remaining high level of aNDFom in the leaf stripper fraction, it is more suited for use as an energy source for monogastrics rather than as a protein supplement. Alternatively, the leaf stripper fraction could be used to increase digestibility and CP content in the feed rations of high producing dairy cows.

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Sammendrag

The large-scale import of soybean products into the EU decreases the self-sufficiency of livestock production. The fractionation of grassland forage crops presents an opportunity to locally produce protein-rich feed for monogastrics. Two promising fractionation methods, twin-screw press juicing and leaf stripping, were evaluated in parallel in field experiments established in Norway and Sweden to compare the nutrient composition and yield of the resulting biorefined and residual fractions. The clearest delineation between the methods was in the ash-free neutral detergent fibre (aNDFom) concentration, with juicing producing a biorefined fraction with a lower aNDFom than leaf stripping. Variability in the allocation of crude protein (CP) and biomass to the biorefined fractions occurred in both methods between cuts and locations and is likely due to differing stand characteristics and inconsistency in machine functionality. Additional work is needed to understand how characteristics such as stand density, botanical composition, and plant phenological stage impact each fractionation method’s ability to allocate protein, fibre, and biomass into the resulting fractions. Future studies should focus particularly on determining standardised settings for leaf stripping machinery based on a range of stand characteristics to ensure consistency in the yield and nutrient composition of the resulting fractions.

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Sammendrag

Climate policies may have adverse geographically unequal socio-economic impacts that, if left unaddressed, may hamper their implementation. This paper examines factors explaining rural-urban perceptions of the effects of climate policy on agriculture and rural areas. The paper adds to current knowledge by jointly analysing socio-economic factors and factors describing the distinct role geographical locations play in shaping these perceptions. We conduct a novel statistical analysis utilising a large preference survey of the Norwegian adult population spatially matched at the municipality level with indexes capturing centrality and the relative importance, and, hence, vulnerability of agriculture to effects of climate change. Our analysis does not identify a principal conflict between the goals of climate policy, rural policy, and agricultural policy across geographical locations. Conflicts along the rural-urban gradient arise around the priority given to the three policy areas, and the concrete impact of climate mitigation measures on rural areas. Centrality more than agricultural properties explains the formation of resistance to policies. The policy process should therefore acknowledge rural concerns, and climate mitigation options should be more carefully designed to avoid further rural-urban polarisation.

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Sammendrag

Chlorella vulgaris is a freshwater microalga that synthesises large amounts of saturated lipids, which makes it suitable for production of bioenergy and biofuels. Since its cultivation usually requires freshwater, it competes with agriculture, economic development and ecological conservation for this limited natural resource. This study investigated the possibility of the partial replacement of freshwater by seawater (50 %) in the growth medium for a more sustainable biomass and lipid production. Chlorella vulgaris 211-11b was cultivated as shake-flask cultures in Bold's Basal Medium (BBM) formulated with 50 % freshwater and 50 % seawater under photoautotrophic, mixotrophic and heterotrophic conditions for eight days with glucose as organic carbon source in the latter two cases. The alga's best growth performance and highest lipid contents (49 % DW−1), dominated by palmitioleic and oleic acid, occurred under mixotrophic rather than photoautotrophic and heterotrophic conditions. This study demonstrates a more economic and ecologically sustainable biomass and lipid production of C. vulgaris by saving 50 % freshwater, which is available for other purposes.