Study Of Major Environmental Problems In Offshore China

With the rapid economic development of China in recent years, marine economy has not only became a new engine of modern economy but also a new resource of economic rim. At the same time, marine is undergoing pollutions and damages at different levels, serious problems such as eutrophication,heavy metal pollution,oils pollution and persistent organic pollutants pollution do harm to the marine ecosystem health. Therefore,based on the special projection'908'data, this paper draws factor distribution maps of seawater chemistry,sediment chemistry and organism qualities in all medias, analyze the current environmental situation and features of China offshore and give suggestions to protect marine environment.Main research contents:(1) EutrophicationComprehensive evaluation index, which based on four factors including water inorganic nitrogen, active phosphate, pH and dissolved oxygen is adopted to demonstrate the eutrophication in offshore water. These research based on the special projection'908'data, in view of surface,bottom water and four seasons.(2) Heavy metalsBased on the special projection'908'data, the contents of copper,lead,zinc,cadmium,chromium,mercury and arsenic in offshore water,organisms and sediments are studied so as to explore the temporal and spatial distribution of heavy metals, and marine heavy metals'environmental effects are evaluated.(3) Sudden oil pollution incidents and offshore oil pollutionsBased on the special projection'908'data, the contents and distribution of oil in offshore water,sediments and organisms are analyzed to evaluate the current offshore oil pollution situation and oil's environmental effects.(4) Persistent organic pollutantsBased on the special projection'908'data, the contents and distribution of persistent organic pollutants in offshore organisms and sediments in coastal cities are analyzed to evaluate the current offshore pollution situation of persistent organic pollutants. The main results show: offshore eutrophication in surface water mainly appear in estuaries which affected largely by terrestrial runoffs, such as Yangtze River estuary,Yellow River estuary,Pearl River estuary,Haihe estuary and Minjiang estuary and their neighboring waters, etc. Pollutions of heavy metals in Bohai Sea rank the first comparing with Yellow Sea, East China Sea and South China Sea. Oil content in most area of offshore including water,organisms and sediments comply with the national first-class standard, excptions show in some part of the offshore, oil content in water and sediments of Bohai Sea are relatively higher for instance, especially in sediments that in oil development zone. The main persistent organic pollutants are 666,DDT and PAHs, the contents in Bohai Sea and East China Sea are higher than those of Yellow Sea and South China Sea.