Biography

I am a soil and water researcher working on agricultural effects on the environment. By combining research approaches of experimentation, modeling and data synthesis, I study drivers and processes controlling nutrient losses from land to water (and air) at soil core to catchment scales and explore mitigation measures to reduce the losses both at source and during transport. I have research experience in Norway, Sweden, Canada, USA and China. While my current research activities can be found on this webpage, my past research experience included: (1) water and nutrient transport from both surface and subsurface pathways, (2) climate and management effects on nutrient losses, (3) management of soil nutrient, fertilizer, manure and biochar, including place-based phosphorus management (variable rate applications), for crop production and environmental protection, (4) effects of crop management, including cover crops and crop residues in combination with tillage, on water and nutrient cycling, (5) drainage and irrigation in paddy and horticulture systems, and (6) field and catchment phosphorus modeling. Through collaborations with other researchers, students and stakeholders in many countries, my research has also involved soil health, crop production, greenhouse gas emissions, and generally sustainable agriculture.

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Division of Environment and Natural Resources

Nutrient balances and use efficiencies for the Timebekken catchment


Grass-based livestock production is important for economy in Rogaland, but concerns are increasingover soil nutrient surplus that contribute to degraded water quality in downstream water bodies. Inthis project, we will improve the understanding of nutrient balances and use efficiencies in Rogalandby measuring grass yield, nutrient contents in grass and total nutrient removal through cropregistration and nutrient analyses in 15 representative fields over two years in the Timebekkencatchment.

Active Updated: 12.04.2024
End: dec 2025
Start: jan 2024
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Division of Environment and Natural Resources

Mitigation measures for phosphorus and nitrogen under changing climate: conflicts and synergies


Nutrient concentrations, loads and stoichiometry (i.e., N:P ratio) in agricultural runoff affect the quality of surface waters. In Norway, the reduction of nutrient runoff is challenged by the sloped landscape, variable weather and changing climate with an increasing number of extreme hydrological events. Mitigation measures for reducing nutrient losses are pressingly needed but they do not always work simultaneously or equally for both N and P, due to the differences in their agronomic and biogeochemical characteristics and dominant transport pathways.

Active Updated: 12.04.2024
End: jun 2025
Start: jan 2024
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Division of Environment and Natural Resources

ENGAGE: Europe Nutrient Management - Guided Approaches for Greater Export reduction


ENGAGE aims to operationalise a novel vision for the future of multi-scale nutrientexport reduction and associated ecosystem services in national andtransboundary/international river basins in Europe by bringing together robuststakeholder engagement strategies with coupled state-of-the-art computationalhydrology techniques and online interactive use-tailored DS tool approaches that integrate remote sensing, socio-economic, governance, and society-change decisionelements. 

Finished Updated: 02.01.2025
End: feb 2028
Start: feb 2025