Abstract
As an important component of aquatic ecosystems, benthic animals are sensitive bioindicators for evaluating water pollution. In this study, we investigated the diversity of macrobenthic communities and analyzed the pivotal environmental factors affecting alterations in the macrobenthic communities of East Taihu Lake. This analysis was augmented by controlled laboratory simulation experiments designed to elucidate and validate the responses of critical indicator species within various functional zones to environmental shifts. This study shows:(1) Bellamya purificata, Limnodrilus and Tubifex were the dominant species on a year-round scale. Water depth was the most important environmental factor affecting the macrobenthic communities;(2) Simulation experiments revealed that the growth condition of Bellamya was significantly worse in the simulated entrance area than in the simulated original enclosure aquaculture and wetland areas. The growth of Radix auricularia was significantly better in the presence of aquatic plants than in the absence of plants, and was more significantly influenced by environmental factors closely related to aquatic plants. The densities of Annelida were significantly higher in the treatment group without plants than that with plants, generally showing the trend of the simulated original enclosure aquaculture area > the simulated entrance area > the simulated wetland area. The trend of diversity was mainly influenced by environmental factors such as turbidity and eutrophication index of the water, which was consistent with the results of the field survey.