Study On Eco-Environmental Pressures Assessment And Their Impacts On The Coastal Zone In The Liaodong Bay

The human activities of economic development and population growth are the primary environmental pressures in Liaodong Bay coastal zones. The worsening coastal zone environment is leading to the invaluable loss of coastal social and economic development. Therefore, it's important to take an apposite countermeasure based on the coastal zone environment pressure analysis. Based on the historical and present documents in the fields of environment, society and economy in the study area, the methods of Eco-Environmental pressures assessment was established, and the pollutants and coastal development were selected as the two main factors. Then the Eco-Environmental pressures and the response of water eutrophication and wetland changes on the coastal zone in the Liaodong Bay were analysed deeply.The primary study fields and achievements include:The assessment index system of ecological and environmental pressure in coastal zone was developed, and the eco-environment stress situation of Liaodong Bay coastal zone was evaluated with the ESI (Eco-environment Stress Index). It shows the environmental pressures primarly due to human activities and economic growt of Liaodong Bay coastal area are consisently increasing, as well as the pressures caused by marine activities and energy exploitation.The annual distribution characteristics of the pollutant fluxes of the major rivers, such as Daling river, Xiaoling river, Liaoriver and Daliao river were analyzed.. With spatical response analysis, it is found that the runoff and sediment discharge of these rivers are not even in the four quarters. More than 60% of the runoff and 80% of sediment discharge happened from June to September. The annual average runoff and sediment fluxes were decreasing from year to year. The runoff and sediment fluxes are afftected much by rainfall and human activities.The pollutant fluxes of Xiaoling River were increasing, while the other three were deceasing.With the improved PEM (Puzzle Evaluation Method), the final gradeof the water eutrophication trned in Liaodong Bay coastal area was studied. It shows that the eutrophicated water are mainly distributed in estuaries of major rivers in the northern Liaodong Bay, while the oligotrophic are distributed in southeasten and middle bay. The eutrophication degree worsened from south to north and from middle sea to seashore. The eutrophication in Liaodong Bay decreased because the pollutant flux into the sea droped from 2003 to 2008.The order of water eutrophication degree is average season, wet season and dry season.The area of mud flat in northern Liaodong Bay is 580.17 km2; it took out 314.21km2 and 243.62km2 mud flat in 1954 and 2000, and 69.19km2 and 195.62km2 in 2000 and 2008. During these two periods, the incrase of mud flat is mainly from riverine transportaion, and the proportions are 79.32% and 98.28% respectively; the decrease of mud flat aws majorly from the human active, and the proportions are 78.79% and 95.15% respectively. Dure to the factors such as regional hydrodynamic, water and sediment from the river and construction, the added area of mud flat lied primarily in west bank of Shuangtaizi River and estuary of Daling River.