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.
2017
Abstract
No abstract has been registered
Authors
Tatsiana Espevig May Bente Brurberg Marina Usoltseva Åslög Dahl Agnar Kvalbein Karin Normann Jo Anne CrouchAbstract
Dollar spot is a destructive and widespread disease affecting most turfgrass species, but until recently it has been absent from the Scandinavian countries of northern Europe. In the fall of 2014, disease symptoms consistent with dollar spot were observed on a golf course fairway in Sweden. A fungus was isolated from symptomatic turf and identified as Sclerotinia homoeocarpa on the basis of ribosomal deoxyribonucleic acid (rDNA) internal transcribed spacer (ITS) sequences, morphology, and culture characteristics. The ITS sequence was identical to isolates of S. homoeocarpa from the eastern and midwestern United States. Koch’s postulates were fulfilled, confirming the S. homoeocarpa isolate as the causal agent. This is the first report of turfgrass dollar spot in Sweden and only the second report of the disease from Scandinavia. Because pesticides are rarely used in the cultivation of Scandinavian turfgrass, dollar spot disease may prove difficult to control through conventional means and potentially represents a major threat to the industry.
Authors
John P. Clarkson Rachel J. Warmington Peter G. Walley Matthew Denton-Giles Martin J. Barbetti Guro Brodal Berit NordskogAbstract
No abstract has been registered
Abstract
Background and aims Decomposition of the finest harvest residues is important for the carbon and nutrient cycle in forest ecosystems both before and after tree felling. We assumed that decomposition is dependent on harvest residue fraction and chemistry, soil temperature and moisture, and aimed at determining decomposition rates and nutrient dynamics of needles, twigs and fine roots from newly felled Picea abies trees in two sites with different climate and topography. Methods Decomposition of needles, twigs and fine roots in mesh bags was followed for up to six years and four years in harvesting sites in eastern and western Norway, respectively. The western site had a more humid climate and a steeper terrain than the eastern site. Results The mass loss after two years was significantly higher for needles (49–59%) than for twigs and fine roots (29–38%). Between sites, there was no significant difference between mass loss for neither needles nor twigs. Nitrogen accumulated in needles during the first year, but 35% of initial needle N had been released after three years. The initial needle and twig decomposition rate was dependent on soil moisture and topographic aspect. During the first three years, needle lignin concentrations retarded whereas P concentrations stimulated needle mass loss. For twigs, P concentrations stimulated mass loss, whereas higher soil temperatures reduced it. Conclusions Lignin and P concentrations of plant parts and soil temperature were the most important factors for the first three-year mass loss. The slow release of nutrients shows the importance of remaining needles, twigs and fine roots as a long-time nutrient source in the ecosystems under study.
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No abstract has been registered
Abstract
No abstract has been registered
Abstract
Habitat loss is one of the primary environmental causes of biodiversity decline across scales; locally to globally. Ecological restoration is acknowledged as an important tool to counteract this negative trend. The semi-natural calcareous sand dune meadows in south-western Norway are known for their high species diversity, much like similar habitats of high conservation value across Europe today. The recent cessation of grazing has caused a decline in several endangered species associated with these habitats due to the advancement of secondary succession. We conducted a long-term restoration experiment in semi-natural dune meadows over 16 years to examine if current trends in biodiversity loss could be reversed and at what time-scale restoration measures take effect. Three treatments were applied; mowing annually, mowing bi-annually, and a control (no mowing). In fields mown annually species richness increased significantly over time. However, the response was slow and significant effects were first seen after year 10. Fields mown bi-annually also showed a similar trend but the response was more variable. Several characteristic meadow species were favoured by annual mowing while they declined in the control fields. Principal component analysis (PCA) revealed a compositional shift, indicating the re-arrangement/-establishment of typical meadow vegetation in the mown sites, contrasting the further successional development in the control. Our results demonstrate the importance of long-term data in supporting good evidence-based management. Annual mowing is effectively restoring this unique habitat, but restoration efforts need to be sustained over many years to show positive effects.
Abstract
Application of fish sludge as fertiliser to agricultural land can contribute to closing nutrient cycles in fish farming. The effect of different treatment technologies on the nitrogen fertilisation effects of fish sludge was studied by a bioassay with barley (Hordeum vulgare), an incubation and a field experiment. Dried fish sludge resulted in relative agronomic efficiency of 50–80% compared with mineral fertiliser. The anaerobic digestate based on fish sludge (20 vol%) and dairy manure did not increase nitrogen uptake in barley. Increasing the ratio of fish sludge in the digestate increased the fertilisation effect, but requires optimisation of the biogas process. A simple logistics analysis conducted for a case hatchery showed that on-site drying and co-digestion of fish sludge in a central biogas plant can be regarded as equal in terms of costs. Norway can become an exporter of fish sludge-based recycling fertilisers if current regulations are modified to facilitate nutrient recycling.
Abstract
No abstract has been registered
Authors
Janka Dibdiakova Liang Wang Hailong LiAbstract
No abstract has been registered