Long-term monitoring in rivers of south germany since the 1970s-Macrophytes as indicators for the assessment of water quality and its implications for the conservation of rivers

Abstract

Since 1970 long-term ecological research has been established in several running waters in Bavaria. An emphasis was laid on the record of the macrophytic vegetation. In this chapter we present long-term records from three rivers. The Moosach is situated in the calcareous-rich gravel plains north of Munich. The two soft-water rivers, the Pfreimd and the adjacent Naab, run out from the siliceous bedrock of the 'Upper Palatinate Forest.' Vegetation changes could be interpreted according to water quality changes and confirmed the suitability of macrophytes as water quality indicators, which recently obtained its official acceptance in the new Water Frame Directive of the European Union. The results show that there is a unification of the vegetation losing the extremes especially in the oligotrophic part. However, the regeneration potential of macrophytes is mainly low although in many species it is not yet understood. It is therefore concluded to lay an emphasis on the protection of still oligotrophic sections of a river to maintain the total species pool. © 2010 Springer Science+Business Media B.V.