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.
2011
Abstract
The recent flooding episode in Norway from May this year shows the necessity of understanding the processes of water discharge from small tributaries feeding the larger river systems. The major objective of the recently started ExFlood project is to define and analyze measures to combat negative impact of extreme weather events on infrastructure in small watershed areas in Norway and to incorporate this in a land use planning tool. Urban, agriculture, nature, and forest areas and infrastructure elements demands different approaches concerning impacts of and opportunities for extreme weather events. The approach of the ExFlood project is to reduce the peak flow and delay the peak time to avoid damages on infrastructure. Three municipalities from different climate regions in Norway contribute to the project where the planning tool will be tested, and an experimental catchment site is selected to conduct in depth process studies.
Abstract
Nutrient losses from agricultural catchments in Norway have been monitored since 1992 as part of the Norwegian Agricultural Environmental Monitoring Programme (JOVA). The catchments are at locations which are chosen to represent typical Norwegian agricultural systems such as the production of cereals, grass/livestock and vegetables. Losses are reported annually.
2010
Abstract
No abstract has been registered
Authors
Petter D. Jenssen Tore Krogstad Adam Paruch Trond Mæhlum Kinga Adam Carlos A. Arias Arve Heistad Lena Jonsson Daniel Hellström Hans Brix Markku Yli-Halla Lasse Vråle Matti ValveAbstract
Nine filter beds have been constructed in the Nordic countries, Denmark, Finland, Norway and Sweden. Filter beds consist of a septic tank followed by an aerobic pre-treatment biofilter and a subsequent saturated flow grass-covered filter. Thus, filter beds are similar to subsurface flow constructed wetlands with pre-treatment biofilters. but do not have wetland plants with roots submerged into the saturated filter. All saturated filters contain Filtralite (R) P. a light-weight expanded clay aggregate possessing high phosphorus sorption capacity. The filter bed systems showed stable and consistent performance during the. testing period of 3 years. Removal of organic matter measured as biochemical oxygen demand (BUD) was >80%, total phosphorus (TP) >94% and total nitrogen (TN) ranged from 32 to 66%. Effluent concentrations of fecal indicator bacteria met the European bathing water quality criteria in all systems. One system was investigated for virus removal and somatic viruses were not detected in the effluent. The investigations revealed that the majority of the BOD and nitrogen removal occurred in the pre-treatment filters and the phosphorus and bacteria removal was more prominent in the saturated filters. The saturated filters could be built substantially smaller than the current design guidelines without sacrificing treatment performance. The used filter material met the Norwegian regulations for reuse in agriculture with respect to heavy metals, bacteria and parasites. When saturated with phosphorus, the light-weight aggregate. Filtralite (R) P used in the saturated bed is a suitable phosphorus fertilizer and additionally has a liming effect. (C) 2010 Elsevier B.V. All rights reserved.
Authors
Frank MillerAbstract
No abstract has been registered
Authors
Frank MillerAbstract
No abstract has been registered
Authors
Frank MillerAbstract
No abstract has been registered
Authors
Frank MillerAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Peatland drainage results in several environmental impacts such as release of greenhouse gas to the atmosphere and leaching of nutrients to watercourses. These hazardous environmental effects can partly be controlled with soil management, and different drainage and remediation practices. Grading is a new method developed for soils with low conductivity suffering from poor drainage, water logging and ice. The soil surface is graded towards the ditch to increase surface runoff and drainage. The present study compares environmental effects of peatland grading compared to traditional intense pipe drainage. Detailed measurements of hydrology, climate, leaching and gas emissions were carried out at adjacent drainage areas with grass cultivation. Additional measurements were made at plots that were abandoned, cultivated with perennial crops, and remained as pristine peatlands. The results show that the leaching of nutrients is highest from pipe drainage. Climate gas emission was considerably higher at all managed sites than from the reference pristine site. Drainage, soil hydrology and soil nutrient status seemed to control gas emissions. The gas emissions were higher than assumed for Norwegian cold conditions. The results confirm observations made on peat soils in other climatic regions. The highest emissions of CO2 was observed when the soil temperature was high and groundwater table low. The N2O emission showed a large variation with no clear pattern. However, at some locations it peaked after a dry period when NO3-N was leached. More CH4 was emitted from the intensively drained site than the graded site, but more CO2 was emitted from the graded site. The difference in leaching and emission properties is partly due to differences in near surface hydrology. At grade sites, a faster runoff response to rainfall occur probably due to shallow throughfall or overland flow which provides better drainage. Also, the graded site was prepared recently, and this can have exposed fresh peat for decay. Therefore the drainage history must be well known in peatland studies as peat change in time due to drainage and cultivation. Abandoned peat field continue to leach greenhouse gases in a same way as cultivated sites.