Abstract: The characteristics of species, abundance and biomass of benthic macroinvertebrates of 6 small connected lakes in Beijing city were investigated from January to December in1987. The results indicate that mollusca, oligochaete and chironomid larvae are dominant groups of macroinvertebrates in the first 3 lakes, and in the other 3 ones, there are oligochaete and chironomid larvae only. Among them, Bellamya putificata only occur in the first 3 lakes, and Pelopia sp. larvae in the other 3 ones. The Shannon species diversity indices (H') show the simitar tendency. It shows that the first 3 lakes belong to mesotrophic, and the other 3 ones to meso-eutrophic. The Shannon species diversity indices(H′) are well corretated with concentrations of BOD, COD, TPand TNin the water. It is possible to evaluate shallow lake trophic level, using diversity index(H′) combined with species indicator of macroinvertebrates.

Key words: Lake, Trophic level, Macroinvertebrate, Community structure, Diversity index