Effects of the Yangshan deepwater port project on zooplankton diversity in adjacent waters of Hangzhou Bay

Based on the data from two seasonal oceanographic surveys in the adjacent waters of Hangzhou Bay (30°32′N-30°50′N, 121°53′E-122°17′E) in the spring (May) and summer (August) of 2001 and 2003-2007, this paper studied the inter-annual variation of species composition and diversity of zooplankton in the waters, and the effects of the Yangshan deepwater port project on the community structure of the zooplankton. In 2003-2007, less change was observed in the species number in May. The species number was the largest in August 2003, and decreased after then. The species number of Mysidaces had an overall increase, but that of Chaetognatha didn’t change significantly. In 2003, owing to the effects of warm current, many offshore and tropical species appeared. From 2003 to 2007, the Shannon-Wiener index (H′) changed less in spring, but the species richness (d) and species evenness (J′) were in decline in summer. The variation of species diversity in summer was mainly attributed to the appearance of offshore species in certain years, which might be closely associated with the warm water current. In short, there was no significant difference in the zooplankton diversity before and after the construction of Yangshan project, but warm water current had evident effects on the species composition and diversity of the zooplankton.