Assessment On Heavy Metals Pollution In Sediments From The Sea Area Of Outlet By Lianzhou Bay In Beihai

Based on the investigation data of the contents of heavy metals(Cu, Pb, Cd, Hg, As)in surface sediments, sea water and biological from the sea area of JingYinYing outlet and HongKan outlet by LianZhou Bay in BeiHai in August of 2010. This paper discussed the distribution of these heavy metals. Technique of single factor index, geoac-cumulation index(Igeo), potential ecological risk index(RI) are applied for assessing the pollution of these heavy metals in sediments, and the pollution of these heavy metals in sea water and biological also been considered. Effective evaluation of the thread are expected to established by the characteristics of distribution and potential ecological risk index of the heavy metals, and the research is helpful for the sustainable development of coastal economic and protection of the ecological environment of LianZhou Bay.(1) The results showes that the sequence of the average concentration of heavy metals in sediments and in sea water by two outlet are all Cu>Pb>Cd>Hg>As , shows that pollution of Cu, and Pb is relatively serious.(2) The sequence of single factor index belongs toâ… sediments in sea area of JingYinYing Outlet is Cu(1.42)> As(0.71)> Pb(0.56)>Hg(0.48)>Cd(0.26), shows that the pollution of Cu is relatively serious, the pollution of Pb, Hg, As and Cd is essentially non-polluted.The sequence of single factor index belongs toâ…¢sediments in sea area of HongKan outlet is Cu(0.24)> As(0.17)> Pb(0.14)> Hg(0.14)> Cd(0.04), shows that the pollution of Cu, Pb, Hg, As and Cd is all essentially non-polluted.(3) The sequence of geoac-cumulation index(Igeo) of JingYinYing outlet and HongKan outlet is Cu(1.48)> Pb(-0.30)> As(-0.70)> Hg(-0.81)> Cd(-1.50), and Cu(0.45)> Hg(-0.33)> As(-0.59)> Hg(-0.33)> Cd(-0.80), which all shows that the geoac-cumulation pollution of Cu is relatively serious calling on more attention,Pb, Hg, As and Cd is non-polluted. (4) The results of potential ecological risk index assessment of JingYinYing outlet show that the polluted grade of potential ecological risk is Hg(34.81)> Cu(22.55)> Cd(20.31)> As(9.42)> Pb(6.22), which shows that these heavy metals have low potential ecological risk. The results of potential ecological risk index assessment of HongKan outlet show that the polluted grade of potential ecological risk is Hg(51.96)> Cd(31.69)> Cu(21.54)> As(10.54)> Pb(6.27), which shows that Hg have middle potential ecological risk and Cu, Pb, Cd, As have low potential ecological risk.(5) The average potential ecological risk of JingYinYing outlet and HongKan outlet was 93.29 and 122.01, which indicated that the sea area of JingYinYing Outlet and HongKan outlet all has low potential ecological risk. The distribution of heavy metals in sediments of tow outlet is all mainly that concentration of heavy metals at the area more close to the pollution source is larger, The results of single factor index, geoac-cumulation index(Igeo), and potential ecological risk index(RI) illustrate this conclusion all. The distribution of these heavy metals in surface sediments, sea water in the sea area of JingYinYing outlet is that contents at the northeast sea area is greater than at the southwest sea area,and The distribution of HongKan outlet is that contents at the east sea area is greater than at the west sea area. The distribution characteristics should be in connection with the hydrodynamic conditions, tide characteristics and sediment transportation of LianZhou Bay.