Earlier research at the Baltic Sea Centre has shown that phosphorus accumulated at land impacts the Baltic Sea for a long time. The project "Legacy nutrient dynamics in the Baltic Sea catchment: implications for managing eutrophication" estimates the legacy storage pools of also nitrogen and how the nutrients are distributed in different parts of the Baltic Sea catchment area. Illustration: Elsa Wikander/Azote

 

Nitrogen and phosphorus are the prerequisite for all life and form an important part of various forms of fertilizer. But in the last century, the handling of manure in agriculture and lack of sewage treatment have led to large amounts of nutrients accumulating in the soil and in the bottom sediments of lakes and rivers.

The project Legacy nutrient dynamics in the Baltic Sea catchment: implications for managing eutrophication will estimate this legacy nitrogen and phosphorus pools at regional scales, the contribution of these pools to current and future loads under different management scenarios, and eutrophication responses of the sea. 

Understanding the contributions of legacy nutrients to loads to the sea is critical for developing eutrophication mitigation plans. The knowledge may enable decision makers to establish reasonable expectations for progress in meeting the goals of the HELCOM BSAP and the Water and Marine Strategy Framework Directives, as well as developing the appropriate tools in the frame of the Common Agricultural Policy (CAP).

Related reading

McCrackin, M., Muller-Karulis, B. et al: A Century of Legacy Phosphorus Dynamics in a Large Drainage Basin

Policy Brief: Phosphorus in the catchment – actions taken today create tomorrow’s legacy