Environment Quality Assessment Of The Shellfish Culture Area At Rudong, Jiangsu Province

Shellfish aquaculture is play an important role in seawater aquacul-ture of ourcountry. With the improvement of living standards,the demand for shellfish alsoincreasing quickly.The expand scale of Shellfish aqua-culture was polluted the shellfishculture area. In order to ensure the health of the shellfish culture area and sustainabledevelopment, grasp the status of the shellfish culture area environment is veryimportant.Based on the data of quartic cruise surveys in Mar., May., Aug., Nov.2010inshellfish culture area of Rudong, this paper carries on a systematical analysis andevaluation of marine ecological environment from two aspects: the seawaterenvironment and the surface sediment environment, and places great emphasis on theintegrative evaluation of shellfish culture area environment.The study also providesreferences to the treatment of marine pollution and to sustainable exploiture of marineresources of shellfish culture area of Rudong.1.The state of seawater environmentThis article has analyzed physical and chemical factors of the seawater in shellfishculture area of Rudong,and showed the variation characteristics of different seasons anddistricts. From the aspect of single-factor assessment, shellfish culture area waters aremainly polluted by DIN、DIP、Zn、Pb and Hg. Taking DIN,DIP,COD,DO as theevaluation indices of organic pollution, he average indices is2.63, the result shows thatthe organic pollution is in a state of elementary pollution.Taking DIN,DIP,COD as theevaluation indices of eutrophic, the average indices is1.45, the result indicates that theeutrophic pollution is in a state of elementary pollution in shellfish culture area. Thestudy makes an evaluation of the seawater environment quality with the Nemerow’sindex, the average indices is2.01, the comprehensive assessing result presents that theseawater in shellfish culture area is lightly polluted.2. The state of sediment environment and the potential ecological risk assessmentWith the index of geoaccumulation,this article has analyzed and assessed thesediment environment in shellfish culture area,and has assessed the potential pollutionrisk of surface sediment which is caused by heavy metals by making use of the methodof potential ecological risk assessment which was proposed by Lars Hankanson. Theresult shows that the sediment environment of shellfish culture area is in a situation of light pollution. The potential ecological risk of sediment environment is at a low level.The sequence of potential ecological risk of different heavy metals in surface sedimentswas Hg>Cd>As>Pb>Cu>Zn. The sequence of potential ecological risk of differentseasons in surface sediments was May.>Nov.>Mar.>Aug..