Assessment of human pressures and their hydromorphological impacts on lakeshores in Europe

Europe has a large number of lakes, many of them lie in densely settled areas. For instance, Germany has 1073 lakes with a surface area greater than 0.5 km2, surrounded by lakeshore habitats of appr. 11 000 km. The lakeshore habitats are of outstanding significance for biodiversity, ecosystem function as well as a variety of human uses. In this paper we give an operational definition of the lakeshore zone (i.e. the littoral zone, the shoreline and the riparian zone). We list significant human pressures directly on the lakeshores or coming from the catchment, and we describe the most important impacts resulting from such pressures. For illustration, we present some examples (eutrophication, morphological modications, hydrological changes) from Lake Constance. Generally, many of these pressures are related to changes to the hydrological regime of the lake and/or to morphological modifications of the shore zone, but knowledge about the links between pressures and specific impacts is poor. We briefly discuss four approaches, which have recently been developed to assess the hydromorphological quality of lakeshores. These procedures are designed to fulfil the requirements of the European Water Framework Directive (WFD), as well as the requirements of regional planning and nature conservation.