Regional Development And Coastal Water Quality:a Quantitative Analysis On The Typical Bays Of Fujian With Management Implications

Coastal ecosystems play an important role in social and economic development.More than 60%of the world's people live within 100 kilometers of the coastline,and highly dependent all kinds of functions and services provided by coastal ecosytems.Since intensity of human activity rising,the coastal ecosystem suffers from anthropogenic disturbed that threatening to environmental health and ecological security.immoderately develop activities can result in a series negative effects on coastal ecosystems,such as ocean acidification,eutrophication,habitat degradation,loss of biodiversity,rising sea levels,and climate change.Rapid urbanization faces severe ecological pressures,especially in semi-enclosed harbor cities as relatively poor hydrodynamic conditions.In order to achieve coastal sustainable development,it is necessary to understand the interaction and degree of human activities on coastal ecosystems,and to manage the ways to develop and utilize coastal resources.In this study,the coastal of Fujian Province and Western Xiamen Bay were selected as examples to study the interaction and degree of regional development on the coastal environment in a quantitative way.This study combines a multivariate statistical and econometric framework for assessment of human activities affecting on coastal environmental quality.First,the structural breakpoint test is applied to explore the relationship between environmental quality change processes and coastal management actions.Secondly,serial application of correlation analysis,principal component analysis,cluster analysis and regression analysis to complete the data screening,data compression,contact establishment and impact ability identification between socioeconomic indicators and environmental indicators.Finally,the Environmental Kuznets Curve model is based on co-integrating the time series of the environmental indicators to analyze the future environmental quality.The Bai-Perron structural breakpoint test was carried out on the water quality changes in Xiamen's West Sea area for nearly 30 years.The results show that(1)DO concentration returned to the 1980s' level after 2008,mainly due to new sewage treatment construction from 1998 to 2006;(2)in this bay,oilspill sources were effectively controlled and the oil concentrationin seawater was reduced since the early 1990s when "industrial waste water discharge permits" were implemented;(3)seawater pH will decrease if we do not effectively reduce acidic gas emissions;and(4)since the 1980s,nutrients concentrations havedoubled for DIN and tripled for DRP.Fortunately,P-limited strate-gies(including updated wastewater treatment plants since 1997,banned P-based detergents since 1999,and banned aquacultureactivities and dredged the channel since 2002)are effective and DRP concentration starts to fall according to the EKC analysis.The multivariate statistical analysis of water quality in Western Xiamen Bay shows that the pH value is more sensitive to socio-economic activities than DIN and DRP,and also matches the order of breakpoint appearances of pH,DIN and DRP.The multivariate statistical analysis of Fujian coast shows that water quality is controlled more by the human activities than the natural regulation.The pollution degree of the seven typical bays is highly positively correlated with the level of social and economic development in Fujian.The improved EKC model of water quality in Western Xiamen Bay supports the"inverted U-shaped" relationship between DRP concentration and per capita disposable income,which means that the nutrient management has made a progress,but it is still necessary to strengthen coastal management and restoration.The panel EKC model of water quality in Fujian coast shows that there is an "inverted U-shaped" relationship between pH,petroleum and economic level,which confirms that the marine oil spill management has achieved substantial results.On the other hand,it supports that the nutrient concentration will increase with socio-economic development,and eutrophication will exacerbate the seawater acidification.Based on the theory of "post-development advantage",China should actively advocate green development,incorporate environmental uncertainty into decision-making,and avoid the recurrence of major marine pollution time.Due to the complexity and dynamics of coastal ecosystems,the ecological response to socio-economic activities is usually non-linear.Further scientific research to optimize coastal management,periodic watershed monitoring programs and data sharing are nec-essary.Interdisciplinary cooperation could better understand thecauses and responses of coastal environmental variations.