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.
2019
Abstract
Nutrient pollution can have a negative impact on the aquatic environment, with loss of biodiversity, toxic algal blooms, and a deficiency in dissolved oxygen in surface waters. Agricultural production is one of the main contributors to these problems; this article provides an overview of and background for the main biogeochemical processes causing agricultural nutrient pollution of surface waters. It discusses the main features of the agricultural impact on nutrient loads to surface waters, focusing on nitrogen and phosphorus, and describes some of the main characteristics of agricultural management, including processes and pathways from soil to surface waters. An overview of mitigation measures to reduce pollution, retention in the landscape, and challenges regarding quantification of nutrient losses are also dealt with. Examples are presented from different spatial scales, from field and catchment to river basin scale.
Abstract
Diffuse phosphorus loss from agricultural fields is an important contributor to the eutrophication of waterbodies. The objective of this study was to evaluate a pilot project for the implementation of mitigation measures to reduce P losses. The pilot project is situated in southwestern Norway and, covers a 14-year period (2004–2018). It included data on the implementation of mitigation measures and water quality monitoring for six small catchments. The mitigation measures consisted of no tillage in autumn, reduced P fertilizer application, grassed buffer zones, and sedimentation ponds. Extra efforts were made to reduce diffuse P losses during the period from 2008 to 2010. The project comprised economic incentives, an information campaign, and farm visits. Data from 2004 and 2010 showed that the use of P fertilizer during this period decreased by 80% and the area of no-till in autumn increased in all six catchments and covered 100% of the area in three of the six catchments in 2010. However, with decreased economic incentives after 2010, the degree to which the mitigation measures were implemented was reversed; P-fertilization increased, and no-till in autumn decreased. No significant effects of mitigation measures on total P and suspended sediment concentrations were detected. We conclude that economic incentives are necessary for the comprehensive implementation of mitigation measures and but that it is not always possible to show the effect on water quality.
Abstract
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Authors
Roger Holten Frederik Bøe Marit Almvik Sheela Katuwal Marianne Stenrød Mats Larsbo Nicholas Jarvis Ole Martin EkloAbstract
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Abstract
A negative impact of multiple anthropogenic stressors on surface waters can be observed worldwide threatening fresh- and marine water ecosystem functioning, integrity and services. Water pollution may result from point or diffuse sources. An important difference between a point and a diffuse source is that a point source may be collected, treated or controlled. Agricultural activities related to crop production are considered as diffuse sources and are among the main contributors of nutrient loads to open water courses, being to a large degree responsible for the eutrophication of inland and coastal waters. Knowledge of hydrological and biogeochemical processes are needed for climate adaptive water management as well as for introducing mitigation measures aiming to improve surface water quality. Mathematical models have the potential to estimate changes in hydrological and biogeochemical processes under changing climatic or land use conditions. These models, indeed, need careful calibration and testing before being applied in decision making. The aim of this study was to evaluate the efficiency of various water protective adaptation strategies and mitigation measures in reducing the soil particle and nutrient losses towards surface water courses from agricultural dominated catchments. We applied the INCA-N and INCA-P models to a well-studied Norwegian watershed belonging to the Norwegian Agricultural Environmental Monitoring Program. Available measurements on water discharge, TN and TP concentration of stream water and local expert knowledge were used as reference data on land-use specific sediment, N and P losses. The calibration and the validation of both the models was successful; the Nash-Sutcliffe statistics indicated good agreement between the measured and simulated discharge and nutrient loads data. Further, we created a scenario matrix consisting of land use and soil management scenarios combined with different climate change scenarios. Our results indicate that land use change can lead to more significant reduction in particle and nutrient losses than changes in agricultural practices. The most favourable scenario for freshwater ecosystems would be afforestation: changing half of the agricultural areas to forest would reduce sediment, total N and total P losses by approximately 44, 35 and 40%, respectively. Changes in agricultural practices could also improve the situation, especially by reducing areas with autumn tillage to a minimum. We concluded, that the implementation of realistic land use and soil management scenarios still would not lead to satisfactory reduction in freshwater pollution. Hence, mitigation measures, enhancing water and particle retention in the landscape – as sedimentation ponds, constructed wetlands etc. – are important in facing the upcoming pressures on water quality in the future.
2018
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Ahmad Hamidov Katharina Helming Gianni Bellocchi Waldemar Bojar Tommy Dalgaard Bhim Bahadur Ghaley Christian Hoffmann Ian Holman Annelie Holzkämper Dominika Krzeminska Sigrun Hjalmarsdottir Kværnø Heikki Lehtonen Georg Niedrist Lillian Øygarden Pytrik Reidsma Pier Paolo Roggero Teodor Rusu Cristina Santos Giovanna Seddaiu Eva Skarbøvik Domenico Ventrella Jacek Żarski Martin SchönhartAbstract
Soils are vital for supporting food security and other ecosystem services. Climate change can affect soil functions both directly and indirectly. Direct effects include temperature, precipitation, and moisture regime changes. Indirect effects include those that are induced by adaptations such as irrigation, crop rotation changes, and tillage practices. Although extensive knowledge is available on the direct effects, an understanding of the indirect effects of agricultural adaptation options is less complete. A review of 20 agricultural adaptation case‐studies across Europe was conducted to assess implications to soil threats and soil functions and the link to the Sustainable Development Goals (SDGs). The major findings are as follows: (a) adaptation options reflect local conditions; (b) reduced soil erosion threats and increased soil organic carbon are expected, although compaction may increase in some areas; (c) most adaptation options are anticipated to improve the soil functions of food and biomass production, soil organic carbon storage, and storing, filtering, transforming, and recycling capacities, whereas possible implications for soil biodiversity are largely unknown; and (d) the linkage between soil functions and the SDGs implies improvements to SDG 2 (achieving food security and promoting sustainable agriculture) and SDG 13 (taking action on climate change), whereas the relationship to SDG 15 (using terrestrial ecosystems sustainably) is largely unknown. The conclusion is drawn that agricultural adaptation options, even when focused on increasing yields, have the potential to outweigh the negative direct effects of climate change on soil degradation in many European regions.
Abstract
The hydrological processes associated with vegetation and their effect on slope stability are complex and so difficult to quantify, especially because of their transient effects (e.g. changes throughout the vegetation life cycle). Additionally, there is very limited amount of field based research focusing on investigation of coupled hydrological and mechanical influence of vegetation on stream bank behavior, accounting for both seasonal time scale and different vegetation types, and none dedicated to marine clay soils (typically soil type for Norway). In order to fill this gap we established hydrological and mechanical monitoring of selected test plots within a stream bank, covered with different types of vegetation, typical for Norwegian agricultural areas (grass, shrubs and trees). The soil moisture, groundwater level and stream water level were continuously monitored. Additionally, soil porosity and shear strength were measured regularly. Observed hydrological trends and differences between three plots (grass, tree and shrub) were analysed and formed the input base for stream bank stability modeling. We did not find particular differences between the grass and shrub plot but we did observe a significantly lower soil moisture content, lower soil porosity and higher shear strength within the tree plot. All three plots were stable during the monitoring period, however modeling scenarios made it possible to analyse potential differences in stream bank stability under different vegetation cover depending on root reinforcement and slope angle.