| Abstract | Triggered by the adoption of the Water Framework Directive, a variety of fish-based systems were developed throughout Europe to assess the ecological status of lakes. This paper provides a comprehensive overview of all existing systems and summarizes sampling methods, fish community traits (metrics) and the relevant anthropogenic pressures assessed by them. Twenty-one European countries developed fish-based assessment systems. Three countries each developed two distinct systems to approach different ecoregions, either to use different data, or to assess different lake types leading to a total number of 24 systems. The most common approach for the setting of reference conditions, used in seventeen systems, was the utilisation of fish communities in comparably undisturbed natural lakes as reference. Eleven used expert judgment, nine historical data and eight modelled relationships. Fourteen systems combined at least two approaches. The most common fish sampling method was a standardized fishing procedure with multimesh-gillnets. Many countries applied combinations of fishing methods, e.g. non-standard gillnets, fyke nets and electrofishing. Altogether 177 metrics were used for index development and each system combined 2-13 metrics. The most common ones were total standardized catches of number and biomass, relative abundance of Perca fluviatilis, Rutilus rutilus, and Abramis brama, feeding preferences, sensitive species, and non-natives. The pressure-response-relationships for these metrics were supported with both correlations established during system development and scientific publications. However, the metrics and their combinations were highly diverse and no metric was applied universally. Our analysis reveals that most fish-based assessment systems address multiple pressures (eutrophication, hydromorphological alterations, fishery pressure and occurrence of non-natives), whilst few are pressure-specific, tackling only eutrophication or acidification. We argue that the value of fish-based systems for lakes lies in their capacity to capture the effect of many different pressures and their interactions which is lacking for most assessment systems based on other biota. |
| Text | 456891 2022 10.1016/j.scitotenv.2021.149620 Ecological indicators Eutrophication Sampling methods Pressure response WFD European fish based assessment reveals high diversity of systems for determining ecological status of lakes David Ritterbusch, Petr Blabolil, Jan Breine, Tibor Eros, Thomas Mehner, Mikko Olin, Graeme Peirson, Pietro Volta, Sandra Poikane Institute for Inland Fisheries, Im Konigswald 2, D 14469 Potsdam, Germany Biology Centre of the Czech Academy of Sciences, Na Sadkach 7, 37005 eske Bud jovice, Czech Republic Research Institute for Nature and Forest INBO , Dwersbos 28, B 1630 Linkebeek, Belgium Balaton Limnological Research Institute, Klebelsberg K. u. 3, H 8237 Tihany, Hungary Leibniz Institute of Freshwater Ecology and Inland Fisheries, Muggelseedamm 310, D 12587 Berlin, Germany Natural Resources Institute Finland, P. O. Box 2, FI 00791 Helsinki, Finland Environment Agency, Research, Analysis and Evaluation, Air, Land and Water Team, Worcester Road, Kidderminster DY11 RA, United Kingdom CNR Water Research Institute IRSA , L.go Tonolli 50, 28922 Verbania Pallanza, Italy European Commission Joint Research Centre JRC , Via Enrico Fermi 274, 21027 Ispra, VA, Italy Triggered by the adoption of the Water Framework Directive, a variety of fish based systems were developed throughout Europe to assess the ecological status of lakes. This paper provides a comprehensive overview of all existing systems and summarizes sampling methods, fish community traits metrics and the relevant anthropogenic pressures assessed by them. Twenty one European countries developed fish based assessment systems. Three countries each developed two distinct systems to approach different ecoregions, either to use different data, or to assess different lake types leading to a total number of 24 systems. The most common approach for the setting of reference conditions, used in seventeen systems, was the utilisation of fish communities in comparably undisturbed natural lakes as reference. Eleven used expert judgment, nine historical data and eight modelled relationships. Fourteen systems combined at least two approaches. The most common fish sampling method was a standardized fishing procedure with multimesh gillnets. Many countries applied combinations of fishing methods, e.g. non standard gillnets, fyke nets and electrofishing. Altogether 177 metrics were used for index development and each system combined 2 13 metrics. The most common ones were total standardized catches of number and biomass, relative abundance of Perca fluviatilis, Rutilus rutilus, and Abramis brama, feeding preferences, sensitive species, and non natives. The pressure response relationships for these metrics were supported with both correlations established during system development and scientific publications. However, the metrics and their combinations were highly diverse and no metric was applied universally. Our analysis reveals that most fish based assessment systems address multiple pressures eutrophication, hydromorphological alterations, fishery pressure and occurrence of non natives , whilst few are pressure specific, tackling only eutrophication or acidification. We argue that the value of fish based systems for lakes lies in their capacity to capture the effect of many different pressures and their interactions which is lacking for most assessment systems based on other biota. 802 Published version https //www.sciencedirect.com/science/article/pii/S0048969721046957 Articolo in rivista Elsevier 0048 9697 Science of the total environment Science of the total environment Sci. total environ. pietro.volta VOLTA PIETRO |
