1. Institute of Environmental Geochemistry, University of Heidelberg, INF 236, 69120 Heidelberg, Germany, School of Agriculture and Food Science, Queen's University of Belfast, Newforge Lane, Belfast BT9 5PX, United Kingdom, Department of Water Quality Control, Technical University of Berlin, Strasse des 17 Juni 135, D-10623 Berlin, Germany, Department of Soil Science and Agricultural Chemistry, Faculty of Biology, University of Santiago, E-15782 Santiago de Compostela, Spain, and Zweckverband Bodensee...