Characteristics And Ecological Risk Assessment Of Pollutants In Surface Sediment Of Jinzhou Bay

In recent years, while the economy of the eastern coastal areas is developing rapidly and mode of production and life of people are changing constantly, the situation of pollution in eastern coastal area of our country is becoming more and more serious.In the east and north coast of Jinzhou Bay, the lifehood of people mainly relies on aquaculture. In recent years, with the rapid development of the construction of Golden beach of Modern Service Industry Development Zone and Airport Logistics Industrial Park, the function of the central part and the coast of Jinzhou bay has been gradually transformed from the traditional industry into a modern service industry and airport logistics industry style,along with the changes of producing and living patterns of the local people.Meanwhile,a large number of heavy metal pollutants is flowing into the coastal waters, which caused environmental problems becoming increasingly serious.Certainly,there will be some changes in marine environment of Jinzhou Bay. Pollutants flowing into the ocean will transform into grains quickly which concentrate among surface sediment in seabed.It makes the sediment becoming more stable and long lasting in usage which is easy to conclude and detect than aquatic medium.It is also a guide to warding the quantity of regional environment. Therefore, it is necessary to research the contaminated sediments of Jinzhou Bay further in order to provide a treatment and observation reference.On the other hand, it is also a statistic support to protect the environment sustainable development.Temporal-spatial characteristics and ecological risk of pollutants in surface sediment of Jinzhou bay were investigated by data which was obtained from 2009 to 2013.The results show that the temporal-spatial characteristics of pollutants in surface sediment of Jinzhou Bay influenced by its geographical position, geological, current, runoff, climate, island and other aspects of natural factors. Besides natural factors, the temporal-spatial characteristics may also have a close relationship with human activities and the level of local economic development.Research shows that pollutant concentration in south bank and the bottom of the bay was higher than north bank and the head of the bay. The concentration of Cu, Pb, Cd, Zn, organic carbon and sulfide obtained in 2013 was higher than that obtained in 2009 and 2010. But the concentration of Hg decreased significantly during the period from 2009 to 2011 and kept stable utill 2013. The concentration of oil increased from 2009 to 2011, but greatly being reduced utill 2013.The potential ecological risk levels of Hg and Cd in heavy metals were moderate to high, and the potential ecological risk levels of Pb, Zn and Cu were lower.When we assess the pollution degree of data which was obtained from 2013 in standard index method,the result shows that the concentration of pollutants in surface sediments of Jinzhou Bay all meet the requirements of the first class of sediment quality standard in GB18668-2002.The order of pollutant level is:Cu>organic carbon>sulfide>Cd>Zn>Pb >oil>Hg.The potential ecological risk index of Cu,Pb,Zn was much less than 40,which implied that those heavy metals had low ecological harm. The potential ecological risk of Cd was in medium to high level and the potential ecological risk of Hg was in high level.The potential ecological risk index of Jinzhou Bay was between 138.89 and 265.87,which implied that the potential ecological risk of Jinzhou Bay was in medium to high level. Judged from the spatial distribution, the potential ecological risk index of the bottom and south coast of Jinzhou Bay is more than the north coast, however, the potential ecological risk index of the middle and the outlet is relatively low.