Spatial variation of crustacean community structure in Yellow Sea and Bohai Sea in Spring

Based on the data collected from bottom trawl surveys in Yellow Sea and Bohai Sea in May 2010, the community structure of crustaceans in different regions of Yellow Sea and Bohai Sea were analyzed. We collected a total of 32 crustacean species, including 18 species of shrimp,13 species of crab, and 1 species of squill. The dominant species changed between different regions. The Crangon affinis which was the most important crustacean species in ecosystem was dominant species in all regions of Yellow Sea and Bohai Sea. We studied the composition of average relative density of crustaceans, found that the biomass of crab was highest in all regions, the average relative biomass of crab was 2.97 kg/h, the individual number of shrimp was highest in all regions, the average value was 1825ind/h. We also studied the spatial distribution of crustaceans, found that the sequence by biomass was Northern Yellow Sea >Southern Yellow Sea >Middle Yellow Sea >Bohai Sea. The diversity of crustaceans in Yellow Sea and Bohai Sea was analyzed, the results suggested that the diversity index were highest in Southern Yellow Sea, lowest in Middle Yellow Sea, no matter by biomass or by abundance. The community similarity was also analyzed, the results suggested that the community similarity index was relatively higher between adjacent waters.