Résumé
Understanding long-term changes of fish diversity and community assembly
rules is crucial for freshwater conservation. Growing evidence indicates
that studying functional and phylogenetic diversity beyond purely
taxonomic considerations can provide different but complementary
information on community assembly. Here, the taxonomic, functional and
phylogenetic β-diversity of fish communities, as well as the community
assembly mechanisms were explored in five impounded lakes of the China’s
South-to-North Water Diversion Project (SNWDP) from the 1980s to the
2010s. We found that: 1) there was an obvious trend of species
homogenization in the five impounded lakes, but the long-term
transformations of different dimensional β-diversities were divergent; 2)
water quality and land use variables have greater impacts in
multi-dimensional β-diversity; and, 3) community assembly process in
taxonomic and functional dimensions were dominated by random process in
both periods, while shifted from limiting similarity to habitat filtering
in the phylogenetic dimension. These results highlight that functional and
phylogenetic diversity are important additional ecological indices for
assessing patterns of fish diversity in lakes.