Two grassland areas are selected as main pilot areas.They are located in the Paulinenaue and the Spreewald in Brandenburg. The areas are characterized by organic soils and a near-surface water table. The first study site is located at the Experimental Research Station in Paulinenaue which cultivates 60 ha of grassland on a fen site. The site in Paulinenaue also features one of the largest groundwater lysimeter systems in Europe. Using more than 100 lysimeters and 15 soil types, the water balance and nutrient dynamics of fen landscapes are investigated in long-term complex studies. Spreewald Wetland is Biosphere Reserve located in the state of Brandenburg in eastern Germany and is home to a rich and diverse range of flora and fauna, including several rare and endangered species. Spreewald wetland has a comparably large catchment area: the Spree catchment area. ZALF easurement station is also available in this area. Both areas are often often flooded in winter and spring.