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.
2025
Abstract
No abstract has been registered
Authors
Begum Bilgic Judit Sandquist Svein Jarle Horn Lu Feng Cecilie Græsholt Asmira Delic Roger Antoine Khalil Michal SposobAbstract
Digestate, a key byproduct of anaerobic digestion (AD), holds residual methane potential (RMP) that must be stabilized or recovered to prevent greenhouse gas emissions after field use. Thermal hydrolysis (TH), typically a pretreatment for AD, improves biogas production. This study assesses RMP in digestates from food waste (FW) and sewage sludge (SS) biogas plants, treated with TH at 160 and 190 °C. For the liquid fraction, FW digestate at 160 °C yielded 1.5 times more methane than untreated digestate, while SS digestate showed a threefold increase. The solid fraction of FW digestate at 160 °C had 1.4 times higher methane yield than untreated, but SS digestate produced less methane after TH. Adding sulfuric acid after TH increased phosphate release but reduced methane production in both digestates. Overall, TH as a post-treatment enhanced organic content release into the liquid fraction, enhancing methane yield, while acid addition improved phosphorus solubility, thereby enhancing digestate's nutrient value. © 2025 The Authors This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/).
Abstract
No abstract has been registered
Abstract
Green roofs provide vital functions within the urban ecosystem, from supporting biodiversity, to sustainable climate-positive ESS provisioning. However, how plant communities should best be designed to reach these objectives, and how specific green roof systems vary in their capacity to support these functions is not well understood. Here we compiled data on plant traits and plant–insect interaction networks of a regional calcareous grassland species pool to explore how designed plant communities could be optimised to contribute to ecological functionality for predefined green roof solutions. Five distinct systems with practical functionality and physical constraints were designed, plant communities modelled using object-based optimization algorithms and evaluated using five ecological functionality metrics (incl. phylogenetic and structural diversity). Our system plant communities supported a range of plant–insect interactions on green roofs, but not all species were equally beneficial, resulting in wide-ranging essentiality and redundancy in ecological processes. Floral traits were not predictive of pollinator preferences, but phylogeny was observed to govern the preferences. Large differences in ecological functionality can be expected between green roofs depending on system design and the extent of the plant community composition. Multifunctionality covariance diverged between systems, suggesting that ecological functionality is not inherently universal but dependent on structural limitations and species pool interactions. We conclude that informed system design has a potential to simultaneously support ecosystem services and urban biodiversity conservation by optimising green roof plant communities to provide landscape resources for pollinating insects and herbivores.
Abstract
Food waste collection in Norway is mostly done using plastic bags, made either of polyethylene or, more recently, of biodegradable plastics, which are materials that can be degraded by microorganisms under certain environmental conditions and time frames. Most of the biodegradable plastic bags used in Norway for food waste collection are labelled as compostable, i.e. degradable under composting conditions, but end up in biogas plants and only rarely in composting plants. The present work provides answers to the following questions. First, to what extent are biodegradable plastic bags deteriorated during anaerobic digestion of food waste. Secondly, is the situation different under mesophilic (37°C) and thermophilic (55°C) conditions. Finally, does thermal hydrolysis (THP) pretreatment of food waste containing biodegradable plastic change the results. In tests offering optimal conditions for microorganisms involved in anaerobic digestion, limited deterioration of biodegradable plastics (Mater-Bi® certified as compostable under industrial (ICP) and home (HCP) composting conditions, representative of what is used in Norway for food waste collection for biogas production) was observed, as shown by limited mass loss (14-21 % for ICP and 22-33 % for HCP) and limited changes in the chemical composition after 22 d, a relevant hydraulic retention time for industrial biogas plant operations. Higher mass loss was observed under thermophilic conditions compared to mesophilic conditions. The effect of THP pretreatment of food waste containing biodegradable plastics offered unexpected results: while a small, non-significant increase in mass loss was observed for ICP, THP led to a significantly reduced mass loss for HCP during anaerobic digestion. The biogas process itself was not significantly affected by ICP and HCP present in food waste at a 4 % plastic to food waste ratio. The present research shows that the majority (79-86 % of ICP and 67-78 % of HCP) of biodegradable plastic residues left after initial pretreatment of food waste, will withstand anaerobic conditions, both under mesophilic and thermophilic conditions, also when subjected to THP pretreatment (5 bars, 160°C, 20 min). This strongly suggests that post-treatment of digestate is required to avoid the spread of biodegradable plastics to agricultural soils, for digestates intended for agricultural use.
Authors
Junbin Zhao Simon Weldon Alexandra Barthelmes Erin Swails Kristell Hergoualc’h Ülo Mander Chunjing Qiu John Connolly Whendee L. Silver David I. CampbellAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Gunhild Bødtker Claire Coutris Eva Marie-Louise Denison Åsa Frostegård Erik J. Joner Bjørn Tore Lunestad Elisabeth Henie Madslien Kaare Magne Nielsen Pål TrosvikAbstract
In this self-tasking scoping review, VKM will map research about the environmental impacts of biodegradable plastics, including biodegradation rates and material persistence in different environments and geographical regions, the influence on microbial ecology and activity, and ecotoxicological effects of materials and associated chemical substances. Related to this is also research associated with the development of methodology, standards, environmental risk assessment, life cycle impact analyses, material sources and properties of biodegradable plastics and products. The aim is to 1) determine the extent of evidence summarised in reviews and original research papers within this emerging research area and 2) map the evidence according to the materials and chemicals studied, types of environments and geographical regions covered, the hypotheses addressed, the type of endpoints assessed and the reported key findings. Systematic literature searches will be performed to identify the summarised evidence, applying APRIO to develop a tailored search protocol that addresses the multi- and cross-disciplinary nature of the research area. We will select and map the identified publications applying Rayyan and sort them into three categories based on their main scientific focus and aim of study: 1) material properties and application, 2) biodegradation and microbial ecology, and 3) ecotoxicology. There will be no geographical restrictions on the search and study selection, but in the data charting process we will highlight findings relevant to Norway and other Nordic countries. The current project adheres to the “Preferred Reporting Items for Systematic Reviews and MetaAnalyses extension for Scoping Reviews (PRISMA-ScR) Checklist” for protocol development and reporting. We will address uncertainties associated with research studies applying EFSA guidelines and their generic list of common types of uncertainty affecting scientific studies and assessments.
Authors
Adrian Unc Majdi R. Abou Najm Paul Eric Aspholm Tirupati Bolisetti Colleen Charles Ranjan Datta Trine Eggen Belinda Eline Flem Getu Hailu Eldbjørg Sofie Heimstad Margot Hurlbert Meriam Karlsson Marius Støylen Korsnes Arthur Nash David Parsons Radha Sivarajan Sajeevan Narasinha J. Shurpali Govert Valkenburg Danielle Wilde Bing Wu Sandra F. Yanni Debasmita MisraAbstract
Arctic food systems blend Traditional Ecological Knowledge with modern, often energy-intensive influences, triggered by colonization. Food systems’ future depends on alignment of tradition with innovation, facilitation of resilience and a heritage-driven interaction with the global economy – at a pace determined by local communities.
Authors
Eirik Gottschalk Ballo William J. D’Andrea Helge Irgens Høeg Kjetil Loftsgarden Manon Bajard Sabine Eckhardt Massimo Cassiani Nikolaos Evangeliou Jostein Bakke Kirstin KrügerAbstract
No abstract has been registered