Patterns, determinants, and management of freshwater biodiversity in Europe Inaugural-Dissertation to obtain the academic degree Doctor rerum naturalium (Dr. rer. nat.) submitted to the Department of Biology, Chemistry and Pharmacy of Freie Universität Berlin by Nike Sommerwerk from Vienna, Austria 2015 Representing work from 4/2008 to 4/2013 and 4/2015 to 10/2015 Supervised by: Prof. Dr. Klement Tockner Dr. Jörg Freyhof in partnership with: Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 310, 12587 Berlin, Germany. 1st Reviewer: Prof. Dr. Klement Tockner Director of the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Berlin, Germany, and Professor in Aquatic Ecology at the Department of Biology, Chemistry, and Pharmacy of the Freie Universität, Berlin, Germany. 2nd Reviewer: Prof. Dr. Daniel Hering Dean of the Faculty of Biology, Head of Aquatic Ecology Department, University of Duisburg-Essen, Essen, Germany. Date of Defense: May 12th, 2016 Contents Contents Summary ............................................................................................................................................. 1 Zusammenfassung ............................................................................................................................... 3 Introduction ......................................................................................................................................... 6 Chapter I Components and drivers of change in European freshwater fish faunas ................................................ 21 1 Abstract ........................................................................................................................................ 21 2 Introduction ................................................................................................................................... 22 3 Methods ........................................................................................................................................ 23 3.1 Dataset .................................................................................................................................. 23 3.2 Data analysis........................................................................................................................... 24 4 Results .......................................................................................................................................... 26 5 Discussion ...................................................................................................................................... 32 6 Acknowledgements ......................................................................................................................... 35 7 References ..................................................................................................................................... 35 Supporting Information A Methods ........................................................................................................................................ 39 B References ..................................................................................................................................... 40 C Results .......................................................................................................................................... 41 Chapter II Responses of the European freshwater biodiversity to anthropogenic stressors & geo-climatic drivers.. 63 1 Abstract......................................................................................................................................... 63 2 Introduction ................................................................................................................................... 64 3 Methods ........................................................................................................................................ 66 3.1 Biological data ........................................................................................................................ 66 3.2 River catchments ..................................................................................................................... 66 3.3 Anthropogenic and natural, geo-climatic descriptors ....................................................................... 67 3.4 Biodiversity metrics .................................................................................................................. 68 3.5 Data analysis........................................................................................................................... 68 4 Results .......................................................................................................................................... 69 4.1 Boosted Regression Tree Analysis (BRT) and additive effects .............................................................. 69 4.2 Generalized Linear Modelling (GLM) and interactive effects ............................................................... 71 5 Discussion ...................................................................................................................................... 73 5.1 Single anthropogenic and geo-climatic effects ............................................................................... 73 5.2 Additive anthropogenic and geo-climatic effects ............................................................................ 73 5.3 Interaction between anthropogenic and geo-climatic effects ............................................................ 74 5.4 Conclusions ............................................................................................................................ 74 6 References ..................................................................................................................................... 75 Supporting Information A Results .......................................................................................................................................... 79 i Contents Chapter III The Danube River Basin ...................................................................................................................... 82 1 Introduction ................................................................................................................................... 82 2 Historical Aspects ............................................................................................................................ 85 3 Palaeogeography and Geology ........................................................................................................... 88 4 Geomorphology .............................................................................................................................. 90 5 Climate and Hydrology ..................................................................................................................... 92 6 Biogeochemistry, Water Quality and Nutrients ........................................................................................ 94 6.1 General Characteristics ............................................................................................................. 94 6.2 Water Quality .......................................................................................................................... 94 7 Biodiversity .................................................................................................................................... 97 7.1 Riparian Vegetation .................................................................................................................. 98 7.2 Vegetated Islands .................................................................................................................... 99 7.3 Macrophytes........................................................................................................................... 99 7.4 Macroinvertebrates ................................................................................................................. 100 7.5 Fish ..................................................................................................................................... 102 7.6 Avifauna .............................................................................................................................. 105 7.7 Wetland Mammals .................................................................................................................. 106 7.8 Herpetofauna ........................................................................................................................ 107 8 Human impacts, conservation and management ................................................................................... 108 9 Major tributaries and the Danube delta ............................................................................................... 113 9.1 Inn River ............................................................................................................................... 113 9.2 Morava River.......................................................................................................................... 116 9.3 Váh River .............................................................................................................................. 118 9.4 Drava River ............................................................................................................................ 121 9.5 Tisza River ............................................................................................................................