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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

Abstract

This report (D2.5) presents a qualitative and quantitative assessment for nutrients and energy regarding circular fertilizers and biogas production from waste resources. A transformation towards sustainable food production for the growing urban population requires improved circular urban nutrient management. Urban agriculture (UA), like any agricultural system, needs input of resources in terms of growth media, nutrients, and water. Resources that are often imported into cities, especially in the form of food, generate urban waste. Current environmental, social, and economic challenges of cities are seen as opportunities that can be derived locally, as this project demonstrates. The domestic organic waste and wastewater contains energy (thermal and chemical) and nutrients that could play a role in the urban circular economy if proper technology and management are applied. Urban organic waste contains relevant nutrients including nitrogen (N) and phosphorus (P), as well as organic matter, yet less than 5% of the global urban resources are presently recycled. One recycling approach is the composting of urban organic wastes, recovery of nutrients from source-separated urine and anaerobic digestate of blackwater, and biogas and biochar produced as sources of energy. At the NMBU showcase different technologies were assessed to demonstrate how to achieve sustainable and circular urban farming systems. Qualitative and quantitative information about organic fertilizers, making budgets for the nutrient contents of waste resources and organic fertilizer and comparing this with the nutrient needs of the plants in the relevant cultivation area, as shown in this report, can provide better fertilization and less loss to the environment. We need more information on the fertilizer value of waste resources and how these nutrients can be best utilised. Due to the increased interest, more information about health and environmental challenges by implementing circular UA should be obtained

To document

Abstract

Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate.