Study of the situation of benthos in the sea area around the sewage outfall of Jiaonan chemical industry area

Based upon the ecological investigation data from June 2002 to July 2002 on the specific composition, the distribution of quantities and the diversity of ecological community of benthos in the sea area around the sewage outfall of Jiaonan chemical industry area are analysed. The results show that the species of benthos is poor and some species, such as Polychaeta, Acaudina molpadioidea, Nassarius variciferus etc., become the dominant species in this sea area; the biomass of benthos is lower and a phenomenon without benthoes species appeares in part sea area. It is also shown that not only both the diversity index and abundance are low but also the dominance of bethoes were great, indicating that the ecological environment of benthoes in the investigation sea area is polluted.