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
Denne rapporten er en litteratursammenstilling over tap av suspendert stoff, fosfor og nitrogen fra arealer med hhv. jordbruk og skog/utmark. I tillegg er det gjort en vurdering av tilsvarende tap i perioden der nydyrking gjennomføres. I de norske studiene som er gjennomgått er gjennomsnittlige tap av nitrogen 17 ganger høyere fra jordbruk enn fra skog. Tilsvarende er fosfortap 56 ganger høyere og tap av suspendert stoff 106 ganger høyere fra jordbruk enn fra skog.
Abstract
No abstract has been registered
Abstract
This chapter highlights the challenges in the agriculture sector in Africa and shows that the current systems are not productive, but are linear, dependent on fossil fuels, and even depleting natural resources. The chapter reviews the potential of sustainable intensification of agriculture with an emphasis on diversified cropping systems and value chain enhancement as an option to promote the bio-based economy in the rural regions of Africa. The chapter uses data and experiences from an ongoing programme in Malawi (www.innovafrica.eu), where maize-legume cropping systems were adopted by smallholders. There is great potential to apply the 3Rs principle of the bio-based economy (i.e., reduce, reuse and recycle) in the farming systems at the production, post-production, marketing and processing stages of the value chain. To sum up, the sustainable intensification approach, inclusive of value chain development, appears to be a promising option for smallholders in Sub-Saharan Africa, which can improve productivity, increase farmers’ income, encourage gender mainstreaming and at the same time reduce environmental impacts.
Abstract
No abstract has been registered
Abstract
To improve risk assessment, control and treatment strategies of contaminated sites, we require accurate methods for monitoring solute transport and infiltration in the unsaturated zone. Highly spatio‐temporal heterogeneous infiltration during snowmelt increases the risk of contaminating the groundwater in areas where de‐icing chemicals are required for winter maintenance of roads and runways. The objective of this study is to quantify how the different processes occurring during snowmelt infiltration of contaminated meltwater affect bulk electrical resistivity. Field experiments conducted at Moreppen experimental lysimeter trench are combined with heterogeneous unsaturated soil modelling. The experimental site is located next to Oslo airport, Gardermoen, Norway, where large amounts of de‐icing chemicals are used to remove snow and ice every winter. Bromide, an inactive tracer, and the de‐icing chemical propylene glycol were applied to the snow cover prior to the onset of snowmelt, and their percolation through the unsaturated zone was monitored with water sampling from 37 suction cups. At the same time, cross‐borehole time‐lapse electrical resistivity measurements were recorded along with measurements of soil water tension and temperature. Images of two‐dimensional (2D) bulk resistivity profiles were determined and were temperature corrected, to compensate for the change in soil temperature throughout the melting period. By using fitted parameters of petrophysical relations for the Moreppen soil, the tensiometer data gave insight into the contribution of water saturation on the changes in bulk resistivity, while water samples provided the contribution to the bulk resistivity from salt concentrations. The experimental data were compared with numerical simulation of the same experimental conditions in a heterogeneous unsaturated soil and used to quantify the uncertainty caused by the non‐consistent resolutions of the different methods, and to increase our understanding of the resistivity signal measured with time‐lapse electrical resistivity tomography. The work clearly illustrates the importance of ground truthing in multiple locations to obtain an accurate description of the contaminant transport.
Authors
Heleen A de Wit Ahti Lepistö Hannu Marttila Hannah Wenng Marianne Bechmann Gitte Blicher-Mathiesen Karin Eklöf Martyn N. Futter Pirkko Kortelainen Brian Kronvang Katarina Kyllmar Jelena RakovicAbstract
Agricultural, forestry‐impacted and natural catchments are all vectors of nutrient loading in the Nordic countries. Here, we present concentrations and fluxes of total nitrogen (totN) and phosphorus (totP) from 69 Nordic headwater catchments (Denmark: 12, Finland:18, Norway:17, Sweden:22) between 2000 and 2018. Catchments span the range of Nordic climatic and environmental conditions and include natural sites and sites impacted by agricultural and forest management. Concentrations and fluxes of totN and totP were highest in agricultural catchments, intermediate in forestry‐impacted and lowest in natural catchments, and were positively related %agricultural land cover and summer temperature. Summer temperature may be a proxy for terrestrial productivity, while %agricultural land cover might be a proxy for catchment nutrient inputs. A regional trend analysis showed significant declines in N concentrations and export across agricultural (−15 μg totN L−1 year−1) and natural (−0.4 μg NO3‐N L−1 year−1) catchments, but individual sites displayed few long‐term trends in concentrations (totN: 22%, totP: 25%) or export (totN: 6%, totP: 9%). Forestry‐impacted sites had a significant decline in totP (−0.1 μg P L−1 year−1). A small but significant increase in totP fluxes (+0.4 kg P km−2 year−1) from agricultural catchments was found, and countries showed contrasting patterns. Trends in annual concentrations and fluxes of totP and totN could not be explained in a straightforward way by changes in runoff or climate. Explanations for the totN decline include national mitigation measures in agriculture international policy to reduced air pollution and, possibly, large‐scale increases in forest growth. Mitigation to reduce phosphorus appears to be more challenging than for nitrogen. If the green shift entails intensification of agricultural and forest production, new challenges for protection of water quality will emerge possible exacerbated by climate change. Further analysis of headwater totN and totP export should include seasonal trends, aquatic nutrient species and a focus on catchment nutrient inputs.
Abstract
Land use and climate change can impact water quality in agricultural catchments. The objectives were to assess long-term monitoring data to quantify changes to the thermal growing season length, investigate farmer adaptations to this and examine these and other factors in relation to total nitrogen and nitrate water concentrations. Data (1991–2017) from seven small Norwegian agricultural catchments were analysed using Mann–Kendall Trend Tests, Pearson correlation and a linear mixed model. The growing season length increased significantly in four of seven catchments. In catchments with cereal production, the increased growing season length corresponded to a reduction in nitrogen concentrations, but there was no such relationship in grassland catchments. In one cereal catchment, a significant correlation was found between the start of sowing and start of the thermal growing season. Understanding the role of the growing season and other factors can provide additional insight into processes and land use choices taking place in agricultural catchments.
Authors
Hannu Marttila Ahti Lepistö Anne Tolvanen Marianne Bechmann Katarina Kyllmar Artti Juutinen Hannah Wenng Eva Skarbøvik Martyn Futter Pirkko Kortelainen Katri Rankinen Seppo Hellsten Bjørn Kløve Brian Kronvang Øyvind Kaste Anne Lyche Solheim Joy Bhattacharjee Jelena Rakovic Heleen de WitAbstract
Nordic water bodies face multiple stressors due to human activities, generating diffuse loading and climate change. The ‘green shift’ towards a bio-based economy poses new demands and increased pressure on the environment. Bioeconomy-related pressures consist primarily of more intensive land management to maximise production of biomass. These activities can add considerable nutrient and sediment loads to receiving waters, posing a threat to ecosystem services and good ecological status of surface waters. The potential threats of climate change and the ‘green shift’ highlight the need for improved understanding of catchment-scale water and element fluxes. Here, we assess possible bioeconomy-induced pressures on Nordic catchments and associated impacts on water quality. We suggest measures to protect water quality under the ‘green shift’ and propose ‘road maps’ towards sustainable catchment management. We also identify knowledge gaps and highlight the importance of long-term monitoring data and good models to evaluate changes in water quality, improve understanding of bioeconomy-related impacts, support mitigation measures and maintain ecosystem services.
Abstract
No abstract has been registered
Abstract
No abstract has been registered