Effects of the Water and Sediment Discharge Regulation Project on Zooplankton in the Yellow River Estuary

The wa ter and sediment discharge regulation (WSDR) project of the Yellow River is yearly implemented from 2002, while there are few reports about its influence on zooplankton. In this paper, we studied the species constitutions, horizontal distribution and community diversity of zooplankton based on the samples collected at 18 sampling stations in the Yellow River estuary in 2014, to compare zooplankton alterations before and after the WSDR project. Phytoplankton, swimming animal and environment variables were investigated simultaneously. RELATE modules of BIOENV in software Primer 6.0 were used to seek the best matches of environmental factors that affect distribution of zooplankton. The results showed that: Species of zooplankton increased while the quantity reduced during WSDR project due to the large reduction in the number of Noctiluca miliaris. Zooplankton community structure became more stable. According to the results of BIOENV analysis, phytoplankton abundance, water depth and inorganic salts had stronger effects on the horizontal distributions of zooplankton.