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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

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Abstract

We compiled published peer-reviewed CO2, CH4, and N2O data on managed drained organic forest soils in boreal and temperate zones to revisit the current Tier 1 default emission factors (EFs) provided in the IPCC (2014) Wetlands Supplement: to see whether their uncertainty may be reduced; to evaluate possibilities for breaking the broad categories used for the IPCC EFs into more site-type-specific ones; and to inspect the potential relevance of a number of environmental variables for predicting the annual soil greenhouse gas (GHG) balances, on which the EFs are based. Despite a considerable number of publications applicable for compiling EFs being added, only modest changes were found compared to the Tier 1 default EFs. However, the more specific site type categories generated in this study showed narrower confidence intervals compared to the default categories. Overall, the highest CO2 EFs were found for temperate afforested agricultural lands and boreal forestry-drained sites with very low tree stand productivity. The highest CH4 EFs in turn prevailed in boreal nutrient-poor forests with very low tree stand productivity and temperate forests irrespective of nutrient status, while the EFs for afforested sites were low or showed a sink function. The highest N2O EFs were found for afforested agricultural lands and forestry-drained nutrient-rich sites. The occasional wide confidence intervals could be mainly explained by single or a few highly deviating estimates rather than the broadness of the categories applied. Our EFs for the novel categories were further supported by the statistical models connecting the annual soil GHG balances to site-specific soil nutrient status indicators, tree stand characteristics, and temperature-associated weather and climate variables. The results of this synthesis have important implications for EF revisions and national emission reporting, e.g. by the use of different categories for afforested sites and forestry-drained sites, and more specific site productivity categories based on timber production potential.

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Abstract

Vitamin E is essential and supplementation to the diet is often needed to meet the requirements of farm animals. This is particularly relevant during long indoor periods where conserved forages must be fed, as conservation can degrade Vitamin E. However, synthetic vitamins are regarded as contentious inputs in organic agriculture. Therefore, the aim of this work was to evaluate if the standard recommendations for supplementation can be revised and adapted for organically managed dairy cows, on the basis of that the diets differ from those in conventional systems. A systematic literature review was conducted to assess the response to Vitamin E supplementation considering lactation and gestation stage and the composition of the basal diet. Most of the experiments that focused on animal health-related issues were conducted during late gestation and early lactation. In more recent studies reporting positive effects of Vitamin E supplementation on animal health and fertility, cows were fed conserved forages such as hay, haylage or maize silage, which all have low natural content of Vitamin E. In the studies reporting no or only minor positive effects of Vitamin E supplementation, cows were often fed diets based on grass or grass-clover silages, which reflects the structure of organic cattle diets. In conclusion, it was proposed that Vitamin E supplementation is not needed for mid and late lactating cows on pasture or fed a basal diet of grass-clover-silages. For dry and peripartum cows as well as for cows fed maize silage, hay or haylage, supplementation was strongly recommended

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Abstract

The Norwegian Scientific Committee for food an Environment (VKM) has assessed an application for authorisation of refined oilseed rape oil (Aquaterra®) derived from genetically modified oilseed rape line NS-B50027-4 for exclusive use as an ingredient in fish feed in Norway. NS-B50027-4 is also named DHA-canola. This report uses the term oilseed rape. NS-B50027-4 produces omega-3 long-chain (≥C20) polyunsaturated fatty acids (omega-3 LC-PUFAs) in its seeds, with a high level of docosahexaenoic acid (DHA) and a small amount of eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA). Aquaterra® also contains a significant level of alpha-Linolenic acid (ALA). Whereas ALA can be derived from plants, the primary producers of EPA and DHA are mainly marine microalgae. EPA and DHA are concentrated in the food chain to fish in the oceans and are often referred to as marine omega-3 fatty acids. NS-B50027-4 was developed as an alternative land-based source of marine fatty acids, mainly DHA. NS-B50027-4 was genetically modified to express seven transgenes derived from yeasts and marine microalgae that encode the enzymes necessary for the biosynthesis of omega-3 long chain polyunsaturated fatty acids. In addition, an eighth gene, pat, was inserted as a marker for selection purposes during development. The pat gene encodes the enzyme phosphinothricin N-acetyltransferase (PAT) conferring tolerance to glufosinate-ammonium herbicides. Equally to conventional refined oilseed rape oils any residues levels of proteins, including the introduced enzymes, will be negligible in the Aquaterra® oil. The risk assessment of Aquaterra® was conducted in accordance with the guidance for risk assessment of derived food and feed from genetically modified plants as described by the European Food Safety Authority (EFSA, 2011a). The risk assessment is based primarily on scientific documentation provided in the application EFSA-GMO-NL-2019-160, which seeks approval for NS-B50027-4 for all applicable food and feed uses in the European Union (EU). VKM concludes that the provided scientific documentation fulfills the criteria of the EFSA guidance and is adequate for risk assessment. VKM concludes that the molecular characterisation, comparative, nutritional, toxicological and allergenicity assessments of NS-B50027-4 do not indicate increased risks to animal or human health compared to its conventional counterpart (comparator) or commercial reference varieties. Based on this together with specific analyses of the seed oil fraction and studies, e.g., in fish, VKM therefore concludes that the refined oil Aquaterra®, is equal to conventional oils from oilseed rape except for the altered composition in fatty acids. VKM concludes there is no increased health risk to fish fed Aquaterra® in feed compared to conventional feeds with oils from other sources, nor is there an indication of increased risk to the environment. Since Aquaterra® is equal to conventional oils from oilseed rape except for the marine omega-3 fatty acids already present in fish feeds, VKM concludes there is no greater need for health or environmental monitoring of feeds containing Aquaterra® than conventional feeds.

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Abstract

Key words: apiculture, biological control, Norwegian Environment Agency, Norwegian Scientific Committee for Food and Environment, predatory mites, risk assessment, varroa Introduction The Norwegian Environment Agency (NEA) have asked the Norwegian Scientific Committee for Food and Environment for an assessment of adverse impacts on biodiversity concerning import and release of the predatory mite Stratiolaelaps scimitus as measure against varroa mites (Varroa destructor) in apiaries. The predatory mite is already in use in Norwegian greenhouses and polytunnels as a biological control agent against dark-winged fungus gnats in a various of plant cultures. The NEA has received an application for a new type of use: to combat varroa mites in apiaries. Background Varroa destructor (the varroa mite) is a species of parasitic mite that feeds externally on honeybees; it is considered one of the major threats to beekeeping world-wide due to its parasitic behaviour and because it acts as a vector for several viral and bacterial bee pathogens. Beekeepers in North America have begun experimenting with introducing Stratiolaelaps scimitus, a commercially available predaceous mite originally used for biocontrol in greenhouses and polytunnels, to control varroa mites, and several studies on the use of the mite in this context have been published recently. The Norwegian Environment Agency has asked VKM to assess the risk to biological diversity in Norway associated with this new use of S. scimitus, and to assess the effects of climate change on any risks that are proposed. Stratiolaelaps scimitus is a tiny (0.5 mm), soil-dwelling predaceous mite that in nature feeds on a wide variety of soil invertebrates, including fly larvae, nematodes, nymphs of thrips, potworms (oligochaetes), springtails, and other mites. For over three decades, Stratiolaelaps scimitus has been produced commercially and the species is now used globally for biological control. The mite is applied to control a wide variety of organisms harmful to food production or to the production of ornamental plants, but especially to combat infestations of fungus gnat larvae, spider mites, flower thrips, and certain plant-feeding nematodes. The species is already used as a biocontrol agent in Norway in greenhouses, open plastic polytunnels used for protecting crops, and in various indoor plantings and fungiculture. Methods VKM established a project group with expertise in entomology, invasion ecology, honeybee behaviour and ecology, and risk analysis of biological control agents. The group conducted systematic literature searches and scrutinized the relevant literature that was found. In the absence of Norwegian studies, VKM relied on literature from other countries. Results and conclusions This VKM assessment concludes with medium confidence that introducing S. scimitus for use in beehives would not significantly increase the probability of establishment and spread of S. scimitus above that of its current use. We point out that there is no evidence that continuous use of S. scimitus in Norway, over decades, has led to its establishment outside of enclosures, including open polytunnels. The optimal temperature for development and reproduction is far higher than what is normally observed in Norway (~28 °C). Although lethal temperature has been reported to be as low as –5.2 °C, we still conclude that S. scimitus would not be able to establish permanent populations in Norway, not even in the southern part of the country as such temperatures are expected to occur in some years throughout the country. Future climate change is not believed to alter this conclusion, since periods with lethally cold temperatures are expected to still occur in the future.