Monitoring selected indicators of ecological change in the Elbe River since the fall of the Iron Curtain

Abstract

The sudden, large-scale cessation of industrial and agricultural practices following the collapse of the communist regimes in the former Czechoslovakia and East Germany, coupled with a set of programmes aimed at reducing industrial and municipal pollutant loads, provided an unique opportunity to observe changes in a severely polluted river, the Elbe. Several sets of data for the post-communist Elbe reflect water quality and ecological health, including surface water pollutants, accumulation in mussels and several species of fish, and diversity of fish species. The ecological health of the Elbe has indeed benefited, and greatly, from post-communist change. The loads of most pollutants in the Elbe surface water have declined significantly over the last decade. Contaminant loading in fish tissue is also declining. Finally, the diversity of fish species in the Elbe is increasing, with a majority of the returning species being native fishes, characteristic of the pre-World War Two Elbe. Nonetheless, several pollutants remain a concern, including nitrate, suspended sediments, mercury, cadmium, hexachlorobenzene, two DDT metabolites, and three HCH isomers. The reasons for these problems include relicts from the communist era and current activities in the Elbe watershed. Further, the invasion of the river by exotic species, while not yet a concern, does remain a threat.