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.
2020
Abstract
Ornamental jewelweed (Impatiens glandulifera Royle) is an alien invasive plant in Europe. This annual plant often grows in riparian habitats where herbicides are prohibited. Several studies have reported the negative effect on ecosystem and ecosystem services by this species. However, limited research is published on control measures and the aim of our study was to explore use of hot water and cutting to control I. glandulifera. A lab experiment showed that the lethal water temperature for seed was between 45 and 50 C. In a pot experiment with seeds in soil, emergence of I. glandulifera was reduced by 78% and 93% compared with the untreated control with volumes of hot water (80 C) of 7.2 and 14.5 L m−2, respectively. When treatments were conducted on relatively tall plants (almost 60 cm) in late June, hot water gave significantly better control than cutting. Compared with an untreated control, I. glandulifera cover was reduced by 97% and 79% after hot water and cutting, respectively. Application of hot water to smaller (<40 cm) and less developed plants (BBCH 12–13) in early June and cutting of plants with visible flower buds (mid-July) led to no significant difference in cover. Compared with an untreated control, I. glandulifera cover was reduced by 99% (cut below first node) and 91% (hot water and cut above first node). When relatively tall plants (almost 60 cm) were treated, hot water use was high (31.1 L m−2) and required twice as many work hours (4.8 min m−2) as cutting (2.4 min m−2). When smaller plants (<40 cm) were targeted, work hours and hot water use were reduced to 2.1 min m−2 and 13.7 L m−2, respectively.
Abstract
There is an increasing interest in plastics, both as a resource and as a pollutant. In Europe, 25.8 million tons of plastic waste are generated each year, and their effects on climate, economy, human and environmental health are major challenges that society needs to address. Although a lot of emphasis is placed on recycling, the use of recycled plastics is still low in the EU. In this context, climate change and environmental concerns have boosted the development of various types of biodegradable plastics. The use of biodegradable plastics spans from disposable containers for food/drink, serviceware and wipes, via waste bags for organic waste collected for biogas production, to agricultural films used to cover soil during vegetable production. However, biodegradable plastics are rarely degraded so quickly and completely that the products disappear in nature, and the label may encourage people think otherwise, enhancing littering. The aim of our study was to describe the fate of biodegradable materials and products during waste treatment, and more specifically during composting. How long does it take these materials to degrade? What are the conditions for degradation, and ultimately, for obtaining plastic-free compost products? To answer these questions, we selected relevant materials, including compostable serviceware, biodegradable plastic bags used for organic waste collection, and biodegradable agricultural mulch films. Composting experiments were performed both at lab-scale (1.5 L containers with externally applied heating) and larger scale (in 140 L insulated compost tumblers, with natural heating from the composting processes, continuously monitored). The endpoints studied were recovery, mass loss, changes in morphology and composition, and microbial analysis of the various composts. In addition, we assessed the applicability of chemical digestion methods used for sample pretreatment of environmental samples containing conventional plastics to biodegradable plastics. Biodegradable plastics is an umbrella term covering materials with diverse polymeric compositions and thus material properties. This was well demonstrated by our selected materials, which displayed distinct degradation behaviors under similar controlled conditions. The time-course of degradation during composting will be presented for all selected materials, together with the main parameters influencing their degradation rates. In addition, some methodological challenges in this research field will be discussed. Finally, experience from a municipal composting facility receiving biodegradable plastic waste will also be presented to put our laboratory-based results into perspective.
Authors
Emil Engelund Thybring Ramūnas Digaitis Thomas Nord-Larsen Greeley Beck Maria FredrikssonAbstract
Wood is a porous, hygroscopic material with engineering properties that depend significantly on the amount of water (moisture) in the material. Water in wood can be present in both cell walls and the porous void-structure of the material, but it is only water in cell walls that affects the engineering properties. An important characteristic of wood is therefore the capacity for water of its solid cell walls, i.e. the maximum cell wall moisture content. However, this quantity is not straight-forward to determine experimentally, and the measured value may depend on the experimental technique used. In this study, we used a triangulation approach to determine the maximum cell wall moisture content by using three experimental techniques based on different measurement principles: low-field nuclear magnetic resonance (LFNMR) relaxometry, differential scanning calorimetry (DSC), and the solute exclusion technique (SET). The LFNMR data were furthermore analysed by two varieties of exponential decay analysis. These techniques were used to determine the maximum cell wall moisture contents of nine different wood species, covering a wide range of densities. The results from statistical analysis showed that LFNMR yielded lower cell wall moisture contents than DSC and SET, which were fairly similar. Both of the latter methods include factors that could either under-estimate or over-estimate the measured cell wall moisture content. Because of this and the fact that the DSC and SET methods are based on different measurement principles, it is likely that they provide realistic values of the cell wall moisture content in the water-saturated state.
Abstract
No abstract has been registered
Authors
Tomasz Leszek WoznickiAbstract
No abstract has been registered
Authors
Tomasz Leszek WoznickiAbstract
No abstract has been registered
Authors
Tomasz Leszek WoznickiAbstract
No abstract has been registered
Abstract
The aim of this work was to calculate farm specific LCAs for milk-production on 200 dairy farms in Central Norway, where 185 farmed conventional and 15 according to organic standards. We assume that there are variations in environmental emission drivers between farms and therefore also variation in indicators. We think that information can be utilized to find management improvements on individual farms. Farm specific data on inputs and production for the calendar years 2014 to 2016 were used. The LCAs were calculated for purchased products and on farm-emissions, including atmospheric deposition, biological nitrogen fixation, use of fertilizer and manure. The enteric methane emission from digestion was calculated for different animal groups. The functional unit was one kg energy- corrected milk (ECM) delivered at farm-gate. For the 200 dairy farms there were huge variations of farm characteristics, environmental per- formance and economic outcome. On average, the organic farms produced milk with a lower carbon footprint (1.2 kg CO2 eq./kg ECM) than the conventional ones (1.4 kg CO2 eq./kg ECM). The organic farms had also a lower energy intensity (3.1 MJ/kg ECM) and nitrogen intensity (5.0 kg N/kg N) than their conventional colleagues (4.1 MJ/kg ECM and 6.9 kg N/kg N respectively). The contribution margin was better on the organic farms with 6.6 NOK/kg ECM compared to the conventional with 5.9 NOK/kg ECM. The average levels of the environmental indicators were comparable but slightly higher than findings in other international studies. The current study proved that the FARMnor model allows to calculate LCAs for large number of individual farms. The results show that the environmental performance and economic outcome vary between farms. We recommend that farm specific LCA-results are used to unveil what needs to be changed for improving a farm’s environmental performance.
Abstract
The aim of this work was to calculate farm specific LCAs for milk-production on 200 dairy farms in Central Norway, where 185 farmed conventional and 15 according to organic standards. We assume that there are variations in environmental emission drivers between farms and therefore also variation in indicators. We think that information can be utilized to find management improvements on individual farms. Farm specific data on inputs and production for the calendar years 2014 to 2016 were used. The LCAs were calculated for purchased products and on farm-emissions, including atmospheric deposition, biological nitrogen fixation, use of fertilizer and manure. The enteric methane emission from digestion was calculated for different animal groups. The functional unit was one kg energy- corrected milk (ECM) delivered at farm-gate. For the 200 dairy farms there were huge variations of farm characteristics, environmental per- formance and economic outcome. On average, the organic farms produced milk with a lower carbon footprint (1.2 kg CO2 eq./kg ECM) than the conventional ones (1.4 kg CO2 eq./kg ECM). The organic farms had also a lower energy intensity (3.1 MJ/kg ECM) and nitrogen intensity (5.0 kg N/kg N) than their conventional colleagues (4.1 MJ/kg ECM and 6.9 kg N/kg N respectively). The contribution margin was better on the organic farms with 6.6 NOK/kg ECM compared to the conventional with 5.9 NOK/kg ECM. The average levels of the environmental indicators were comparable but slightly higher than findings in other international studies. The current study proved that the FARMnor model allows to calculate LCAs for large number of individual farms. The results show that the environmental performance and economic outcome vary between farms. We recommend that farm specific LCA-results are used to unveil what needs to be changed for improving a farm’s environmental performance.
Authors
Geneviève J. Parent Claudia Méndez-Espinoza Isabelle Giguère Melissa Magerøy Martin Charest Éric Bauce Joerg Bohlmann John J. MacKayAbstract
We review a recently discovered white spruce (Picea glauca) chemical defense against spruce budworm (Choristoneura fumiferana) involving hydroxyacetophenones. These defense metabolites detected in the foliage accumulate variably as the aglycons, piceol and pungenol, or the corresponding glucosides, picein and pungenin. We summarize current knowledge of the genetic, genomic, molecular, and biochemical underpinnings of this defense and its effects on C. fumiferana. We present an update with new results on the ontogenic variation and the phenological window of this defense, including analysis of transcript responses in P. glauca to C. fumiferana herbivory. We also discuss this chemical defense from an evolutionary and a breeding context.