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Research article - Peer-reviewed, 2013

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

Phillips, Geoff; Lyche-Solheim, Anne; Skjelbred, Birger; Mischke, Ute; Drakare, Stina; Free, Gary; Järvinen, Marko; de Hoyos,, Caridad; Morabito, Giuseppe; Poikane, Sandra; Caravalho, Laurence


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.


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

Published in

2013, volume: 704, number: 1, pages: 75-95
Publisher: SPRINGER

Authors' information

Phillips, Geoff
Lyche-Solheim, Anne
Norwegian Institute for Water Research (NIVA)
Skjelbred, Birger
Norwegian Institute for Water Research (NIVA)
Mischke, Ute
Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB)
Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment
Free, Gary
Environment Protection Agency
Järvinen, Marko
de Hoyos,, Caridad
Centro de Estudios y Experimentación de Obras Públicas (CEDEX)
Morabito, Giuseppe
National Research Council (CNR)
Poikane, Sandra
Institute for Environment and Sustainability (JRC-IES)
Caravalho, Laurence
Centre for Ecology and Hydrology (CEH)

Associated SLU-program

Lakes and watercourses

Sustainable Development Goals

SDG6 Clean water

UKÄ Subject classification

Environmental Sciences

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