Abstract: In order to understand the community pattern and biodiversity of macrobenthic fauna in Xiangshan Bay, an eight cruises survey was made at thirteen stations of the Bay from July 2006 to August 2007, with the dominant species composition, richness, biomass, secondary productivity, and P/B value of macrobenthic fauna investigated, and the species diversity of the macrobenthic fauna analyzed. A total of 123 macrobenthos species were recorded, including 48 species Mollusc, 33 species Crustacea, 12 species fish, 12 species annelid polychaete, 8 species echinoderms, and some coelenterates and nematodes. The dominant species were more concentrated, and the dominance index was higher. The average secondary productivity of the macrobenthic fauna was 16.70 g·m^-2·a^-1, and the average P/B  value was 0.60. There existed distinct variations (P<0.01) in the species richness index (d), evenness index (J), Simpson’s diversity index (D), and Shannon diversity index (H) among different survey stations, and distinct variations (P<0.01) in the indices except evenness index (J) between years.

Key words: Xiangshan Bay, macrobenthic fauna, dominant species, secondary productivity, biodiversity, monoculture agriculture, ecological imbalance, sustainable security agriculture, organic agriculture.