Research Of The Ecological Security In Tianjin Coastal Zone

The coastal zones are located at the junction of the two major ecosystems of ocean and land and have gathered a large number of goods,population and funds,because of its rich natural resources,superior location conditions and comfortable natural environment.As a result,the coastal resources were becoming deficient and the environment was getting worse,which made the ecological security in coastal zones in grave danger worldwide.This paper took the Tianjin coastal zone as the study area to research its long-term dynamic evolution of ecological security situation.Considering on the perspective of sea-land coordination management,this study combined the ocean health index and urban ecological security to select the concrete indicators and eventually developed an assessment system of ecological security in coastal zones based on the Pressure-State-Response(PSR)model.The weights of each indicator,each factor and each subsystems were calculated by the comprehensive application of analytic hierarchy process(AHP)and the entropy method(EM).The comprehensive index method was used to evaluate the ecological security of Tianjin coastal zone from 2000 to 2014,and the results were further supported by the fuzzy comprehensive method.Based on the improved GM(1,1)and the gray relational method,the future ecological security situations of Tianjin coastal zone were forecasted and the main influencing factors were determined.At last,some targeted improvement and optimization measures were purposed to achieve the sustainable development of coastal zones.The main conclusions were following:1.The ecological security index of pressure subsystem showed a trend of linear decline.The main influencing factors included reclamation area,marine catch production,mariculture area,straight into the sea industrial waste water and fertilizer application intensity.Through the forecast,it was found that its future ecological security index continued to decline which indicated that the pressures from every aspects were increasing in the context of large-scale and high-intensity human activities.2.The ecological security index of state subsystem showed a fluctuating trend.The main influencing factors included the biodiversity index,the water qualitycompliance rate of the coastal water,the greening coverage of the built area and the area of cleaner.Through the forecast,it was found that its future ecological security index showed a steady state of fluctuating changes,in early warning situation.On one hand,it was closely related to the pressures beared by coastal zone.On the other hand,the states of each indicators exited deterioration phenomenon.3.The ecological security index of response subsystem showed a linear upward trend.The main influencing factors included the area of natural reserve,the ratio of tertiary industry to GDP,research and development expenditure,sewage treatment rate and environmental pollution control investment.Through the forecast,it was found that its future ecological security index showed a increasing trend which was a good reflection of the positive effects of every response measure.4.The ecological security composite index showed a stable fluctuation change,but the value was not high,all in the early warning states.Through the forecast,it was found that its future ecological security index showed a decline trend where there was a big gap from the ideal stage.The control efforts of the pressure subsystem should be strengthened and paid more attention in the follow-up management,at the same time,a variety of response optimization and state improvement measures should be enhanced to hlep improving the overall ecological security level.