Reducing nutrient loadings from agricultural soils to the Baltic Sea via groundwater and streams

Soils2Se RefsgaardCoordinator: Jens Christian Refsgaard, Geological Survey of Denmark and Greenland, Copenhagen
Total budget: EUR 3.3 million
Duration: 4,25 years, 1.1.2014-31.3.2018

Summaries of annual reports:
BONUS SOILS2SEA year 3 report
BONUS SOILS2SEA year 2 report
BONUS SOILS2SEA year 1 report


Most of the nutrients leaching from agricultural land and discharged from point sources are retained in groundwater and surface water before reaching the Baltic Sea. This retention shows significant spatial variation depending on the local hydrogeological and riverine regime. Therefore the traditional uniform regulations that do not account for local data and knowledge are much less cost-effective than spatially differentiated regulations with measures targeted for areas, where the natural retention is low. BONUS SOILS2SEA will i) develop new methodologies and tools for planning of differentiated regulations based on new knowledge of nutrient transport and retention in surface and subsurface waters; ii) evaluate how spatially differentiated regulation can offer more cost-efficient solutions to reducing nutrient loads to the Baltic Sea; iii) analyse how changes in land use and climate may affect the nutrient load to the Baltic Sea as well as the optimal location of measures aiming at reducing the load; and iv) develop new governance and monitoring concepts that acknowledge relevant aspects of EU directives and at the same time are tailored towards decentralised decision making aiming at incorporation of local scale knowledge required to optimally design differentiated regulation measures. The concept and tools will be tested at a hierarchy of scales ranging from small scale (km2) through medium scale catchments (thousands of km2) to the Baltic Sea basin scale (millions of km2).

: nutrient retention, spatially differentiated regulation, land use change, governance, stakeholder involvement

Partners: Denmark, Germany, Poland, Russia, Sweden

Introductory article: see BONUS in Brief December 2013

For more information visit BONUS SOILS2SEA's website and the BONUS projects' website.