Abstract
For understanding the water quality state of Jialing River in Nan Chong ,the community structure characteristics of
zooplankton were investigated in both dry and rainy seasons. By Shannon-wiener diversity index, Margalef richness
index and Pielou evenness index and the combination of dominant species in the indicator species in the section was
discussed. Results show that a total of 45 species were collected and identified, the kinds of zooplankton are mainly
composed of Protozoa, 53% of the total, 9 species of Rotifer, 7 species of Cladocera, 5 species of Copepoda. The
average number is 2740.5 ind/ L , the average biomass is 2.2654 mg/ L. Evaluation results determine the water
quality in Nanchong city of Jialing River belong to the moderate pollution. It was suggested that the further work
departments should be carried out to strengthen the necessary consolidate management and ecological repair.
Key words: zooplankton; community structure; diversity Index; water quality assessment