The Danube nutrient loads are affected by human impacts mainly from agriculture and waste water
discharges. Knowledge about the Danube nutrient loads and the changes of these loads over time is essential for
understanding the changes within the ecosystem of the Black Sea, induced by these loads. The paper shows the long
term changes of the nutrient load along the Danube estimated by measurements from different countries and
institutions. The results show large differences between Dissolved Inorganic Nitrogen (DIN) and Total Phosphorus
(TP). For TP, the Danube River loads show a strong decrease since 1988-1992, especially in the Middle and Lower
basin. This change is probably partly connected to the dramatic economic changes in the Middle and Eastern European
countries following the collapse of the communist system. The DIN load does not show a decreasing trend in the last
decade. The data indicate that there may be a decreasing trend in the anthropogenic emissions, but that such a trend is
counteracted by a significantly increasing trend of the Danube discharge in the last decade. The accuracy of the
available data is analysed in the paper as well.
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