Nutrient Balances for Danube Countries: A Strategic Analysis

Issues of nutrient management were studied in ten countries of the Danube Basin in the frame of the Danube Environment Programme. Comprehensive data collection covered socio-economic and natural factors influencing nutrient balances, water quality of the Danube and its tributaries, and major features of wastewater management for municipalities. The innovative methodology of materials accounting was applied to develop nutrient balances for the countries involved and the Danube Basin, and to get insight on causes, temporal changes of stocks and early recognition. The approach was cross-checked against loads estimated from ambient water quality observations. Main dilemmas of water quality management (local problems, and the regional eutrophication of the Danube Delta and the Black Sea) were identified and options of load reductions were evaluated. Agriculture pollution of mostly non-point source origin was found as the key of developing an integrated emission reduction policy for the Basin. Municipal wastewater management strategies were studied in detail. Recommendations were given on strategy development, monitoring, research and improved international cooperation in the Danube/Black Sea Basin.