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A phytoplankton trophic index to assess the status of lakes for the Water Framework Directive


Despite improvements in wastewater treatment systems, the impact of anthropogenic nutrient sources remains a key issue for the management of European lakes. The Water Framework Directive (WFD) provides a mechanism through which progress can be made on this issue. The Directive requires a classification of the ecological status of phytoplankton, which includes an assessment of taxonomic composition. In this paper, we present a composition metric, the plankton trophic index, that was developed in the WISER EU FP7 project and demonstrate how it has been used to compare national phytoplankton classification systems in Northern and Central Europe. The metric was derived from summer phytoplankton data summarised by genus from 1,795 lakes, covering 20 European countries. We show that it is significantly related to total phosphorus concentrations, but that it is also sensitive to alkalinity, lake size and climatic variables. Through the use of country-specific reference values for the index, we demonstrate that it is significantly related to other national phytoplankton assessment systems and illustrate for a single European (intercalibration) lake type how it was used to intercalibrate WFD boundaries from different countries.

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The paper is a result of the project WISER (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). We would like to thank Birger Skjelbred, Jannicke Moe and Bernard Dudley who supported data management and extraction and especially thank all the data providers. These include (figures in brackets give the number of WBs): Mediterranean GIG (Data manager: Caridad de Hoyos, CEDEX-CEH). Spain: Ministerio de Agricultura, Alimentación y Medio Ambiente (122), Centro de Estudios Hidrográficos (CEDEX-CEH) (46). Italy: Università degli Studi di Sassari. Dipartimento di Scienze Botaniche, Ecologiche e Geologiche (DiSBEG) (18). Portugal: Instituto da Água, I.P. (INAG) (18), Romania: Ministeriul Meduli şi Pădurilor (MMP) (10). Cyprus: Ministry of Agriculture, Natural Resources and Environment, Water Development Department (MANRE-WDD) (7). France: Institut national de recherche en sciences et rechnologies pour l′environnement et l′agriculture (IRSTEA) (6), Greece: Maria Moustaka, Aristotle University of Thessaloniki. Central-Baltic GIG (Data manager: Ute Mischke, IGB). Estonia: Estonian University of Life Sciences (EMU) gathered for the state monitoring programme supported by the Estonian Ministry of Environment. Latvia: Latvian Environment, Geology and Meteorology Centre. Lithuania - EPA Lithuania. Denmark: National Environmental Research Institute, University of Aarhus. Belgium: Jeroen Van Wichelen, Ghent University (UGENT). Netherlands: Rijkswaterstaat (RWS). Germany: Data from German water bodies were kindly provided by the following institutions of the German Federal States: Landesamt für Umwelt, Gesundheit und Verbraucherschutz Brandenburg (LUGV; 127), Ministerium für Landwirtschaft, Umwelt und Verbraucherschutz Mecklenburg-Vorpommern (MLUV, Seenprogramm, 65), Landesbetrieb für Hochwasserschutz und Wasserwirtschaft Sachsen-Anhalt (LHW, 5), Landesamt für Landwirtschaft, Umwelt und ländliche Räume Schleswig–Holstein (LLUR, 13), Senatsverwaltung für Gesundheit, Soziales und Verbraucherschutz Berlin (SenGUV, 12), Niedersächsische Landesbetrieb für Wasserwirtschaft, Küsten- und Naturschutz (NLWKN, Sulingen, 1). Poland: Data were provided partly by the Institute of Environmental Protection - National Research Institute. The Inspection for Environmental Protection provided data obtained within the framework of state environmental monitoring. Hungary: Environmental Protection Inspectorate for Trans-Tiszanian Region. Northern GIG (Data manager: Geoff Phillips, EA). Finland: Finnish Environment Institute (SYKE). Sweden: Swedish University of Agricultural Sciences (SLU). Norway: Norwegian Institute for Water Research (NIVA). United Kingdom—Scottish Environment Protection Agency (SEPA) and the Environment Agency for England & Wales (EA). Ireland: Environment Protection Agency (EPA).

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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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Phillips, G., Lyche-Solheim, A., Skjelbred, B. et al. A phytoplankton trophic index to assess the status of lakes for the Water Framework Directive. Hydrobiologia 704, 75–95 (2013).

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  • Phytoplankton
  • Eutrophication
  • Europe
  • Water Framework Directive
  • Trophic index
  • Intercalibration
  • Classification
  • Indicator taxa