Evaluation And Evolution Analysis Of Ecological Environment Quality In Tianjin Coastal Waters

The coastal waters are the most active areas between land,sea and atmosphere.About 60% of the population live within 100 km of the coastal area.The quality of the ecological environment will be strongly interfered by human activities.As an important seaport of China's Bohai Economic Circle,Tianjin plays an important role in the integrated development of Beijing,Tianjin and Hebei.However,with the development of social economy,the ecological environment of Tianjin's coastal waters has become increasingly prominent.The research on the evaluation of marine ecological environment quality and the evolution trend of Tianjin coastal waters can better solve the problem of coordinated development between economic development,resource allocation and marine ecological environment in Tianjin,and promote the sustainable development of social economy and ecological environment.This paper summarizes the relevant theories and practical researches on the evaluation of the ecological environment quality of coastal waters by domestic and foreign scholars,and expounds the development status and connotation of the evaluation of ecological environment quality in coastal waters.On this basis,this paper selects the relatively mature PSR model to carry out the evaluation of the ecological environment quality of Tianjin coastal waters.First,the evaluation indicators are screened in order to objectively and truly reflect the current ecological environment of Tianjin's coastal waters.Secondly,based on the PSR model,the evaluation index system of Tianjin's coastal water environment is established.The analytic hierarchy process is used to determine the weights of indicators at all levels.The single factor index combined with the compliance rate method and the comprehensive index evaluation method are used to carry out the Tianjin coastal marine ecosystem.Overview.This paper analyzes the current ecological environment quality of the coastal waters of the Bohai Bay from the three aspects of pressure,state and response,and analyzes and summarizes the evolution trend of the ecological environment in the coastal waters of the Bohai Bay in recent years,and proposes solutions and suggestions.In the future,scientific and technical support will be provided for the ecological environment quality protection and management of Tianjin coastal waters.The text evaluation results show that the comprehensive final score of Tianjin's coastal water environment quality is 0.6337,the ecological environment quality is good,and there is room for improvement of “0.1663”.However,the gap from the general level is only 0.0337.If the social and economic activities of human beings intensify and the pollution control is unqualified,it is likely that the quality of the ecological environment in Tianjin's coastal waters will fall to a general level,which requires us to be cautious.The final score of the stress index is 0.2591,indicating that the social and economic activities in Tianjin have had a large negative impact on Tianjin's coastal waters,which has brought more severe pressure on Tianjin's coastal waters ecosystem;The final score of the status indicator is 0.7947,indicating that the ecological environment quality of Tianjin's coastal waters is in good condition and maintained in a relatively stable state,but the comprehensive score of biological evaluation is low,only 0.7000.Remind us that we should pay more attention to the protection of marine living resources in the following production and life,strictly monitor the discharge of pollutants from the land source into the sea,and prohibit the reclamation activities;The final score of the response indicator is 0.3884,indicating that the Tianjin government still needs to increase investment and protection of Tianjin's coastal waters.The marine ecological environment protection has a long way to go.Based on the statistical analysis of the monitoring results in the past five years,it is found that the main influencing factor of seawater quality in the coastal ecological monitoring area of Tianjin is inorganic nitrogen,but the degree of impact has been reduced.Among the various marine environmental monitoring indicators,the content of surface active phosphoric acid and the dissolved oxygen salt in the bottom layer showed an overall upward trend;Surface salinity,bottom active phosphate,bottom chemical oxygen demand and bottom inorganic nitrogen content all showed a downward trend;pH,surface dissolved oxygen,surface chemical oxygen demand,surface inorganic nitrogen,petroleum and bottom salinity content all showed a stable trend;The sediment quality in the offshore monitoring area of Tianjin is generally good,but the sulfide content is generally on the rise and needs to be paid attention to prevent it from harming the sediment environment;At present,it has been found that there are a few sites in the petroleum and sulphide content that exceed the sediment quality standards required by the corresponding marine functional zoning,which should be paid attention to by the relevant departments.The marine life status in Tianjin's coastal waters is generally stable.However,due to the occurrence of red tide disasters in 2016 and 2017,various marine biological indicators have experienced large fluctuations.Red tide disasters are the dominant factors affecting the marine life status in Tianjin's coastal waters.