Temporal Distribution of Fish Community Structure in Dongting Lake Estuary

摘要

The Dongting Lake Estuary is migration pathways for some river-lake migratory and semi-migratory fishes. In the present study, an annual survey of fish was conducted from January to November 2018 covering a total of 6 sites in Dongting Lake Estuary. A total of 57 freshwater species and subspecies belonging to 5 orders and 10 families were recorded. The catches at the Dongting Lake Estuary were mainly composed of Lake settled fish. The biomass of Cyprinus ( Cyprinus ) carpio Linnaeus was the highest, accounting for 25.53% of the total catches, followed by Hypophthalmichthys molitrixs , Culter alburnus Basilewsky and Ctenopharyngodon idellus , accounting for 10.41%, 8.99% and 7.10% of the total catches, respectively. The four major domestic carps accounted for 26.13% of the total catch. The range of richness of species varied between 40 and 51 species. The trend was fewer species in spring, with the arrival of summer and autumn gradually increasing, peaking at the turn of summer and autumn, and then gradually decreasing with the arrival of winter, to the lowest in spring. The Shannon, Simpson, Pielou and Margalef indices showed the consistent trends with richness of species.