Eutrophication induces functional homogenization and traits filtering in Chinese lacustrine fish communities

2023

Article référencé dans le Web of Science WOS:000906899700001

Feng K., Deng W. B., Zhang Y. Z., Tao K., Yuan J., Liu J. S., Li Z. J., Lek S., Wang Q. D., Hugueny Bernard

Science of the Total Environment, 2023, 857 (3), p. 159651 [10 p.] ISSN 0048-9697

Rapid anthropogenic nutrient enrichment has caused widespread ecological problems in aquatic ecosystems and the resulting eutrophication has dramatically changed fish communities throughout the world. However, few studies ad-dressed how fish communities responded to eutrophication in terms of multidimensional functional and taxonomic structure, especially how eutrophication acted as an environment filter on functional traits. The aim of the present study was to investigate the effects of eutrophication on fish species composition, community metrics and species func-tional traits in 26 shallow lakes from the middle reaches of Yangtze River basin, China. This study validated that eu-trophication is an important factor shaping the fish community structure. Regression analyses showed that eutrophication favored higher total biomass and lower functional diversity of fish communities but had little effect on species richness. Despite the fact that some pelagic zooplanktivorous species were more abundant in the most eu-trophic lakes, multivariate analyses of the relationships between species traits and environmental variables revealed weak relationships between feeding traits and eutrophication. In contrast, species with a benthic life stage were neg-atively associated with eutrophication while those with a large body size and high absolute fecundity showed the op-posite trend. Due to demersal habitat degradation, and to a lesser degree, to changes in trophic resources availability, eutrophication caused functional simplification of fish communities by increasing functional traits homogeneity among the most tolerant species. Some relationships between functional traits and eutrophication well established in the western palearctic have not been observed in this study, emphasizing the importance of biases resulting from specific evolutionary histories. This work will provide useful insights on on-going restoration and management of shal-low lakes in the Yangtze River basin.

Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Sciences du milieu [021] ; Limnologie biologique / Océanographie biologique [034] ; Ecologie, systèmes aquatiques [036]

CHINE ; YANGTZE BASSIN

Fonds IRD [F B010086840]

fdi:010086840