Community Structure And Biodiversity Of Macrobenthos In Jiming Island

The ecological study of macrofauna was conducted on nine representive sampling stations sampled monthly from Oct2008 to Oct2009 in the southern part of Jiming Island, including shrimp pond (YX1) , the outlet of the shrimp pond (YX2) , a clam pond that is next to the shrimp pood (YG1) , a place that keep clam at intertidal (YG2) , a place near to the fisheries dock (YM1), a place far from the fisheries dock (YM2), a place near to the travelers dock (KM1), a place far from the traverlers dock (KM2), a river estuary (HK). Abundance and biomass of macrobenthos were investigated by quantitative study.The macrobenthos community structure and biodiversity were analyzed through multivariate statistic analysis.The ABC method (abundance biomass comparison) was used to detect pollution-induced disturbance in marine benthic communities.Polychaete,mollusk and crustacean were the main macrobenthos. It was polychaete that in the largest quantity, which was assistant with the native environment. Mollusk was in the second place in quantity under less disturbance of human in intertidal zone.There was obvious difference between stations inside and outside the raft-cultural area in abundance and biomass. Compared with the past studies on macrobenthos in other sea aera, the total of species and individual are less. YG1 had the most total of individual with YG2 in the second place,but less than YG2 in total of species, which was because YG1 had more individuals in such exceptional species as Halosydnopsis pilosa. YM1 was more seriously polluted than YM2, so the total of species of YM1 was less than that of YM2.The total numbers of species and individual of KM1 were relatively less than KM2.HK had more species of Halosydnopsis pilosa, but less in others.YX1 was less in total of both species and individual because of disinfection and interference of human. There were seasonal changes in population composition nearby Jiming Island. In general, there were larger total numbers of species and individuals in each station in spring and in summer, but less in winter and in fall.The biodiversity was in remarkable difference in every station from the analysis of biodiversity of macrobenthos. Meanwhile, there were apparently seasonal changes in total of species, index of Shannon-Wiener and index of evenness. The biodiversity and index of evenness were lower in spring and winter than in summer and autumn.