Community structure of two rotifer populations and ecological assessment of water quality in Miyun Reservoir

Abstract

In order to understand the changes in the ecological environment of Miyun Reservoir after the South-to-North Water Transfer Project, our study investigated the changes in the composition and structure of two indicator species in the Miyun Reservoir and applied the rotifer biological assessment method to analyse the changes of water ecological environment. Our results showed that a total of 10 species of the genera Trichocerca and Brachionus were identified during the investigation with an average annual abundance of 542.124 ind./L and 102.68 ind./L, respectively. Among them, T. pusilla and T. cylindrica were the dominant species of the genus Trichocerca, and the majority of Brachionus species were B. diversicornis, B. angularis, B. caudatus. Variance results showed that there were significant differences in the abundance of these two rotifer pupations at different inter-annual and spatial scales during the survey. The biological evaluation indicated that the water quality has gradually changed from eutrophication to oligotrophication after the South-to-North Water Transfer Project, and the ecological environment was maintained well. Our results will provide necessary ecological parameters for water environment protection and ecological safety management of Miyun Reservoir.