A preliminary study of spatio-temporal relationship among three groups of fishery species caught in bottom trawl survey in the Bohai Sea

To investigate the spatio-temporal relationship among the main fishery resources in the Bohai Sea, we carried out a bottom trawl survey there from August 2014 to May 2015, and then made a preliminary analysis of the horizontal spatial distribution, spatial distance and the seasonal characteristics of three groups of fishery resources. The results show that the concentration areas of the three groups of fishery resources demonstrated spatial differentiation. The trend of spatial differentiation became more and more significant, as the concentration areas of the three groups aggregated. The distance among three groups was longer in summer and autumn than in winter and spring. Among the three groups of fishery resources, the distance between cephalopoda and crustacean was relatively short, while the distances between cephalopoda and fish, and fish and crustacean were relatively longer, which was associated with difference of the locomotivity of the three groups of organisms.