TY - JOUR
T1 - Macrophyte assessment in European lakes: diverse approaches but convergent views of ‘good’ ecological status
AU - Poikane, Sandra
AU - Portielje, Rob
AU - Denys, Luc
AU - Elferts, Didzis
AU - Kelly, Martyn
AU - Kolada, Agnieszka
AU - Mäemets, Helle
AU - Phillips, Geoff
AU - Søndergaard, Martin
AU - J. Willby, Nigel
AU - van den Berg, Marcel S.
PY - 2018/11
Y1 - 2018/11
N2 - The European Water Framework Directive has been adopted by Member States to assess and manage the ecological integrity of surface waters. Specific challenges include harmonizing diverse assessment systems across Europe, linking ecological assessment to restoration measures and reaching a common view on 'good' ecological status. In this study, nine national macrophyte-based approaches for assessing ecological status were compared and harmonized, using a large dataset of 539 European lakes. A macrophyte common metric, representing the average standardized view of each lake by all countries, was used to compare national methods. This was also shown to reflect the total phosphorus (r
2 = 0.32), total nitrogen (r
2 = 0.22) as well as chlorophyll-
a (r
2 = 0.35-0.38) gradients, providing a link between ecological data, stressors and management decisions. Despite differing assessment approaches and initial differences in classification, a consensus was reached on how type-specific macrophyte assemblages change across the ecological status gradient and where ecological status boundaries should lie. A marked decline in submerged vegetation, especially Charophyta (characterizing 'good' status), and an increase in abundance of free-floating plants (characterizing 'less than good' status) were the most significant changes along the ecological status gradient. Macrophyte communities of 'good' status lakes were diverse with many charophytes and several
Potamogeton species. A large number of taxa occurred across the entire gradient, but only a minority dominated at 'less than good' status, including filamentous algae, lemnids, nymphaeids, and several elodeids (e.g.,
Zannichellia palustris and
Elodea nuttallii). Our findings establish a 'guiding image' of the macrophyte community at 'good' ecological status in hard-water lakes of the Central-Baltic region of Europe.
AB - The European Water Framework Directive has been adopted by Member States to assess and manage the ecological integrity of surface waters. Specific challenges include harmonizing diverse assessment systems across Europe, linking ecological assessment to restoration measures and reaching a common view on 'good' ecological status. In this study, nine national macrophyte-based approaches for assessing ecological status were compared and harmonized, using a large dataset of 539 European lakes. A macrophyte common metric, representing the average standardized view of each lake by all countries, was used to compare national methods. This was also shown to reflect the total phosphorus (r
2 = 0.32), total nitrogen (r
2 = 0.22) as well as chlorophyll-
a (r
2 = 0.35-0.38) gradients, providing a link between ecological data, stressors and management decisions. Despite differing assessment approaches and initial differences in classification, a consensus was reached on how type-specific macrophyte assemblages change across the ecological status gradient and where ecological status boundaries should lie. A marked decline in submerged vegetation, especially Charophyta (characterizing 'good' status), and an increase in abundance of free-floating plants (characterizing 'less than good' status) were the most significant changes along the ecological status gradient. Macrophyte communities of 'good' status lakes were diverse with many charophytes and several
Potamogeton species. A large number of taxa occurred across the entire gradient, but only a minority dominated at 'less than good' status, including filamentous algae, lemnids, nymphaeids, and several elodeids (e.g.,
Zannichellia palustris and
Elodea nuttallii). Our findings establish a 'guiding image' of the macrophyte community at 'good' ecological status in hard-water lakes of the Central-Baltic region of Europe.
UR - https://www.sciencedirect.com/science/article/pii/S1470160X1830503X
U2 - 10.1016/j.ecolind.2018.06.056
DO - 10.1016/j.ecolind.2018.06.056
M3 - A1: Web of Science-article
C2 - 30393465
SN - 1470-160X
VL - 94
SP - 185
EP - 197
JO - Ecological Indicators
JF - Ecological Indicators
ER -