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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.

2024

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Abstract

Semi-natural hay meadows are among the most species-rich habitats in Norway as well as in Europe. To maintain the biodiversity of hay meadows, it is important to understand local management regimes and the land use history that has shaped them and their biodiversity. There is however a general erosion of Traditional Ecological Knowledge (TEK), related to hay meadows and other semi-natural habitats. This review aims to examine historical and written sources of land use practices related to hay meadows and to discuss the implications of a re-introduction of TEK in present and future management practices. Traditional land use practices and TEK obtained from written sources from four Norwegian regions and for the country as a whole are compared with present management practices. Written sources show that hay meadows have been managed in a complex but flexible way. Today's management regimes of hay meadows in Norway are streamlined and strongly simplified, most often involving only one late mowing and in some cases grazing. This simplification may result in loss of biodiversity. The potential to include more variety of management practices in hay meadows, by utilizing knowledge from written sources more systematically in combination with farmers’ experienced knowledge (TEK) should be better utilized. Such an approach may secure both the biodiversity in hay meadows and TEK for the future. Former and present landscape ecological contexts in the infield-outlying land system show that management should be done for larger landscapes rather than small, isolated hay meadows, to optimize biodiversity conservation. For this study, we conducted a Norwegian literature review, based on ethnographical and ethnobotanical sources, as well as historical and present agricultural statistics, historical maps, results from research projects, and other sources. Our findings are discussed with similar European studies focusing on the historical management of hay meadows.

Abstract

Since the 1950s, the use of plastics in agriculture has helped solving many challenges related to food production, while its persistence and mismanagement has led to the plastic pollution we face today. Soils are no exception and concentrations of polyethylene mulch debris up to 380 kg/ha have been reported in Chinese agricultural soils. A variety of biodegradable plastic products have thus been developed and marketed, with the aim to solve plastic pollution through complete degradation after use. But the environmental conditions for rapid and complete degradation are not always fulfilled, and the risk that biodegradable plastics could also contribute to plastic pollution must be evaluated. In this presentation, we want to share the knowledge gained through research projects on biodegradable plastics in agricultural soil, where we both studied the degradation of biodegradable mulch under Nordic soil conditions, and the fate of other biodegradable plastics in soil amendments such as compost and biogas digestate. A two-year field experiment with biodegradable mulch (PBAT-starch and PBAT-PLA) buried in soil in mesh bags showed that also under colder climatic conditions does degradation occur, involving fragmentation already after 2 months, but that complete degradation may take 3 to 9 years, depending on soil temperature and soil organic matter content (both correlate positively with degradation rate). Accumulation is therefore likely to happen when biodegradable mulch is repeatedly used every year. A full-scale experiment with compostable plastic cups (PLA) at an industrial composting plant, where we followed their fate and conducted metagenomic analysis over 13 weeks, demonstrated the major role played by fungi for a successful degradation of PLA. However, the successful management of biodegradable plastic products largely depends on existing waste management infrastructure. Most biodegradable plastic bags, labelled as compostable and used for food waste collection do not end up in industrial composting plants in Norway, but in biogas production plants. Here, we showed that these plastic bags (Mater-Bi®) are only marginally degraded (maximum 21-33 % mass loss) during biogas production, and likely to end up in biogas digestate and then in agricultural soils, unless digestate is treated to remove plastic residues.

Abstract

Since the 1950s, the use of plastics in agriculture has helped solving many challenges related to food production, while its persistence and mismanagement has led to the plastic pollution we face today. Soils are no exception and concentrations of polyethylene mulch debris up to 380 kg/ha have been reported in Chinese agricultural soils. A variety of biodegradable plastic products have thus been developed and marketed, with the aim to solve plastic pollution through complete degradation after use. But the environmental conditions for rapid and complete degradation are not always fulfilled, and the risk that biodegradable plastics could also contribute to plastic pollution must be evaluated. In this presentation, we want to share the knowledge gained through research projects on biodegradable plastics in agricultural soil, where we both studied the degradation of biodegradable mulch under Nordic soil conditions, and the fate of biodegradable plastics in two major soil amendments: compost and biogas digestate. A two-year field experiment with biodegradable mulch (PBAT-starch and PBAT-PLA) buried in soil in mesh bags showed that also under colder climatic conditions does degradation occur, involving fragmentation already after 2 months, but that complete degradation may take 3 to 9 years, depending on soil temperature and soil organic matter content (both correlate positively with degradation rate). Accumulation is therefore likely to happen when biodegradable mulch is repeatedly used every year. A full-scale experiment with compostable plastic cups (PLA) at an industrial composting plant, where we followed their fate and conducted metagenomic analysis over 13 weeks, demonstrated the major role played by fungi for a successful degradation of PLA. However, the successful management of biodegradable plastic products largely depends on existing waste management infrastructure. Most biodegradable plastic bags, labelled as compostable and used for food waste collection do not end up in industrial composting plants in Norway, but in biogas production plants. Here, we showed that these plastic bags (starch-based polymer) are only marginally degraded (maximum 21-33 % mass loss) during biogas production, and likely to end up in biogas digestate and then in agricultural soils, unless digestate is treated to remove plastic residues.

Abstract

The purpose of the experiment was to investigate whether the Potato Cyst Nematode (PCN) will survive steam treatment in SoilSaver. The results from the SoilSaver experiments show that heat treatment with steam affects PCN’s ability to hatch from the eggs. Juveniles who did hatch, died shortly after. No larvae or eggs that survived the treatment were found in any of the replications.