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Effects of physico-chemistry, land use and hydromorphology on three riverine organism groups: a comparative analysis with monitoring data from Germany and Austria

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Abstract

The majority of studies comparing the response of biotic metrics to environmental stress in rivers are based on relatively small, homogeneous datasets resulting from research projects. Here, we used a large dataset from Austrian and German national river monitoring programmes (2,302 sites) to analyse the response of fish, diatom and macroinvertebrate metrics to four stressors acting at different scales (hydromorphology, physico-chemistry, riparian and catchment land use). Nutrient enrichment and catchment land use were the main discriminating stressors for all organism groups, over-ruling the effects of hydromorphological stress on the site scale. The response of fish metrics to stress was generally low, while macroinvertebrate metrics performed best. The Trophic Diatom Index (TDI) responded most strongly to all stressors in the mountain streams, while different metrics were responsive in the lowlands. Our results suggest that many rivers are still considerably affected by nutrient enrichment (eutrophication), which might directly point at implications of catchment land use. We conclude that monitoring datasets are well-suited to detect major broad-scale trends of degradation and their impact on riverine assemblages, while the more subtle effects of local-scale stressors require stream type-specific approaches.

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Acknowledgments

We would like to thank Piet Verdonschot, ALTERRA, Netherlands, for calculation of diatom metrics by OMNIDIA. We gratefully acknowledge the provision of biotic and environmental data by the following institutions and projects: Austrian Federal Ministry for Agriculture, Forestry, Environment and Water Management (including all Austrian Federal States); Federal Agency for Water Management, Institute of Water Ecology, Fisheries and Lake Research; Office of the Provincial Government of Lower Austria; German Federal States Bavaria, Hesse, Rhineland-Palatinate, Northrhine-Westphalia, Lower Saxony, Schleswig–Holstein, Mecklenburg-Vorpommern, Sachsen-Anhalt, Saxony and Thuringia; AQEM project; STAR project. We thank Martin Seebacher for patiently compiling and extracting data. We are also grateful for the comments of an anonymous reviewer, which helped improve the manuscript. This paper results from the WISER project (Water bodies in Europe: Integrative Systems to assess Ecological status and Recovery) funded by the European Union under the 7th Framework Programme, Theme 6 (Environment including Climate Change) (contract No. 226273), www.wiser.eu.

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Guest editors: C. K. Feld, A. Borja, L. Carvalho & D. Hering / Water bodies in Europe: integrative systems to assess ecological status and recovery

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Dahm, V., Hering, D., Nemitz, D. et al. Effects of physico-chemistry, land use and hydromorphology on three riverine organism groups: a comparative analysis with monitoring data from Germany and Austria. Hydrobiologia 704, 389–415 (2013). https://doi.org/10.1007/s10750-012-1431-3

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