Abstract: In this study, zooplankton and environmental factors in Datong Lake of Hunan Province were investigated monthly. Zooplankton community structure and its relationships with environmental factors were analyzed by canonical correspondence analysis (CCA) to provide reference for fisheries sustainable utilization in Datong Lake. The characteristics of water nutritional levels, trophic state index (TSI-M) and dominant zooplankton species indicated that the lake was under accelerated eutrophication status. A total of 46 species from 20 genera were identified, which consisted of 18 species of Protozoa, 19 species of Rotifera, 4 species of Cladoera and 5 species of Copepoda. According to the abundance and occurrence, Tintinnopsis sinensis, Brachionus diversicornis, Asplanchna priodonta, Polyarthra trigla, Filinia longiseta, Bosmina longirostris and Cyclops strenuous were considered as the dominant species. The mean annual abundance and biomass of zooplankton were 1013±125 ind·L^-1 and 5.12±0.96 mg·L^-1, respectively. The abundance and biomass were both relatively high from October to March 2014, and lowest in April, with a spatial pattern of decreasing from South to North. The Shannon index (H), abundance index (D), and Pielou index (J) of the zooplankton community were 0.31-1.88, 0.11-1.39, and 0.45-0.90, respectively. The CCA results indicated that water temperature and total phosphorus concentration were the two main environmental factors affecting the zooplankton community structure in the Datong Lake. The stocking of silver carp and bighead carp as well as the spatial distribution pattern of Mollusca might also play an important role in determining the zooplankton community structure in this shallow lake.

Key words: biocontrol, endophytic bacteria, green fluorescent protein, Bacillus subtilis, colonization threshold