Author(s): Jiajian Qiu; Hongwu Tang; Saiyu Yuan

Linked Author(s): Saiyu Yuan, Hongwu Tang

Keywords: Large river; Floodplain lake; Fish spatial distribution; Habitat characteristics

Abstract: Floodplain lakes of large rivers are important supplements to the biodiversity of the river network ecosystems. Distinct environmental conditions between rivers and lakes respectively support their own unique fish populations. However, there are few studies on the transition of fish communities and habitat characteristics between rivers and lakes. The present study was undertaken in the Poyang Lake outflow channel, which connects the Yangtze River with Poyang Lake. A field survey was conducted by means of fish hydroacoustic detection, acoustic velocity profiling and water environment parameter measurement during the flood season of Poyang Lake. The results shows that there were two different distribution patterns of fish communities in the outflow channel. In the reach close to the Yangtze River with high flow velocity, large water depth and relatively narrow range of habitat conditions, the fish density were relatively low and fish mainly distributed in the main channel and along the riparian zone. Higher fish density occurred in the reach close to the main lake district of Poyang Lake, where contained a wide range of habitat conditions, and was characterized by high water temperature, high dissolved oxygen and high chlorophyll content, and the distribution of fish was relatively uniform. Understanding the spatial distributions and transition processes of fish communities between rivers and lakes is essential for the management and conservation of the ecological processes of the river network ecosystem.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1309-cd

Year: 2023