Research On The Environmental Carrying Capacity Analysis Applied In The Plan Environmental Impact Assessment

Since the environmental carrying capacity (ECC) theory was brought forward in the 1920s, it has taken effect greatly for alleviating the stress of the man-land relationship and solve the contradiction between environment and development. It has also served as the criterion of coordination among the economic-social-environment relationship. For ensuring the PEIA to put into effect successfully, the PEIA technique guideline was issued by the Ministry of Environmental Protection of China in 2003. The guideline recommends that the ECC analytical method is one of the technical methods in PEIA. While the ECC theory and the PEIA are so complicated and uncertain, the ECC application research in PEIA has not been given enough importance for long time, and the successful case study if it is scare. By using the research methods of literature study, systems analysis, the theory and practice combining etc, this paper discusses the routes and methods of ECC application in the PEIA, and with a view to rich the EIA database techniques for guiding the implementation of the PEIA effectively as well as playing a reference role. The main research results are as following:1) This dissertation analyzes the definition, connotation, characteristic of the ECC theory, as well as the main factors that can influence the scale of the ECC; and give the technical route and framework for the ECC analysis in PEIA that is the combination of the single ECC factors and the comprehensive ECC analysis. Especially in the single ECC factors analysis stage, we can use supply and demand analysis of the economics, based on the identifying bottlenecks of the ecosystem elements, and then emphasize the constrainting ECC factors analysis.2) In the stage of comprehensive ECC analysis, based as the P-S-R or D-S-R pattern, referencing the research results of home and abroad, adopting the aim-criterion-domain-index frame, referencing to the State Environmental Protection Department, "Plan Environmental Impact Assessment Technical Guidelines," and the strategy of sustainable development indicators system which put forward by the SD study group of the Chinese Academy of Sciences, we selected 55 ECC indicators primarily. And the principles such as the scientific and systematic, dynamic and stability of combined operational, the combination of universal and regional, etc, are followed in the process, using the methods of frequency statistics, multicollinearity analysis and the combining expert advice, to construct the comprehensive ECC evaluation index system of the study area, mainly including 20 independent factors such as the Regional Planning degree from the land-use suitability, water resources using intensity, SO₂ emissions etc, and adopt the improving method of fuzzy evaluation to establish indicators of the evaluation of quantitative models.3) Finally, applied the established technical methods of ECC analysis of PEIA into the Tianjin Binhai New Area advanced manufacturing industry zone to verify its practicality and feasibility.(1) Through the single ECC factors analysis such as water and land resources, and environmental capacity etc, results showed that after the implementation of planning, industrial zone of water demand volume is about 706,000m³/d, while the regional water supply capacity of total fresh water is about 430,000m³/d. We can solve the gap by reclaimed water resources which the volume is 372,000m³/d, it includes the sewage treatment reuse 312,000m³/d and rainwater utilization30,000m³/d as also as desalination 30,000m³/d.The land resources have the higher carrying capacity and the land-use suitability is in the "appropriate" or "more appropriate" level, so it can illustrate that the living and industrial land-use planning is reasonable.The environmental capacity of SO₂ and PM₁₀ is about 29,000t/a and 26,000t/a respectively, and it can meet the requirement of the "Eleventh Five-Year Plan" which reduced the 10% of the total pollution emission than the base year of 2005 only through measures such as dust removal and desulfurization. The region does not have the environmental capacity of COD, and COD emission of various types of waste water is about 3946t/a in the Status quo, considered various scenarios, it will be about 2020t/a in 2010, and then about 1164t/a in 2020, so the water pollution situation is still very serious.(2) The comprehensive ECC analysis showed that: the Planning's ECC index value in the status quo is 0.446, which belongs to the "saturation level". If the effective measures are not taken, we can forecast that comprehensive ECC index value will be 0.409 and 0.406 in 2010 and 2020 respectively, which is not suitable to further develop in large-scale. Through adopting the measures of the economic, technological, and policy tools, the regional comprehensive ECC index value will show a gradual upward trend, which will be 0.502(2010) and 0.645(2010) respectively. The coordination index value of "Economic-Social-Environmental" was also gradually increased from 0.474(2005) to 0.518(2010) and 0.633(2020) respectively, and the planning zone will have the best development cycle gradually.(3) The regional environmental impact's mechanism showed that comprehensive ECC index value and COD emissions have a high correlation (-0.698) than other factors. This shows that water pollution is still a key factor that affected the advanced manufacturing industrial zone's environmental carrying capacity. Therefore, to improve the quality of regional water environment, a strict control on the emissions of water pollutant is still a foucal point for regulation of future environment.(4) Based on the all the above ECC analysis results for advanced manufacturing Industrial Zone, we can adopt the six aspects of proposals such as water-saving cycle, adjustment and optimization of industrial development, the development of recycling economy and clean production, pollution control, urban infrastructure improvement and strengthening the environmental management as reference for decision makers.To sum up, a combination of the technique of single ECC analysis and the comprehensive ECC analysis, we can not only improve the evaluation of the resources and environmental problems but can also properly deal with the economic and social problems concerned for the plan. The ECC analysis is practical and feasible and can be easily integrated with the PEIA, and more importantly, the ECC analysis results can feed back to the plan, and give the advice or adjustment based on our results. This paper will be the reference to effectively guide the PEIA.