Planning Environmental Imapct Assessment For Urban Development

Planning environmental impact assessment (PEIA) for urban development which aims to ensure environmental and possibly other sustainability aspects in urban development process is considered to be a systematic decision support process, making a big difference in urban policy, plan and programme making. It continues to be a major challenge for human communities in the dynamic and rapidly evolving world. A considerable number of researches and applications have been carried out in recent decades on various aspect of PEIA for urban development, however, most of them studied on environmental carrying capacity based on combinative method of semi-quantitative and qualitative analyses and concluded with qualitative evaluation conclusion, lack of focuses on systemic theoretical mechanism, quantitative environmental index with rigid constraints, and comprehensive integration technology. Thus, in this study, we conduct a research on PEIA systemic theoretical mechanism and combinative method of quantitative and qualitative analysis, analyse and optimize the PEIA system for urban development, and take Dalian City as a case study.On the basis of sustainable development, environmental carrying capacity, circular economy and system theory, this research studies the complex system performance of PEIA for urban development and analyses it by SWOT method. The study indicates that, subsystem of PEIA system has significant relative hierarchical structure in which system elements exist with not only dendritic serial but also transverse spread parallel structure. That technical method is deficient and need to be improved can be considered as one of restrictive factors for urban development PEIA system. Based on routine methods of strategic environmental assessment screened, a comprehensive technical method which stresses the quantitative method while combining it with the qualitative method has been established, which includes correlation analysis, curvilinear regression, analytic hierarchy process, grey correlation analysis methods, system dynamics, fuzzy comprehensive evaluation, grey multi-objective model, expert judgement method, and scene analysis method.This paper takes PEIA for urban development planning of Dalian City (2003～2020) as a case study, forecasts and assesses the impact of central urban development planning, traffic planning, water resources planning and municipal infrastructure planning on atmospheric environment, water resource environment and municipal solid waste disposal management based on established comprehensive technical method. The simulated results indicate that, by the year2020, the atmospheric environment pollution SO2will be0.146mg/m3, NO2will be0.139mg/m3taking account of soot and vehicle emission, water resources demand will be6×109m3, and municipal solid waste conveying will be3512.7t per day, waste low heating value will increase to5542.9kj/kg with social-economic development.Grey correlation analysis methods, system dynamics, and fuzzy comprehensive evaluation methods are used to assess the environmental impact of status quo scheme, inertial scheme and planning scheme. The results indicate that planning scheme of energy structure and transportation in central urban development planning and traffic planning can definitely minify the adverse effect on atmostphere environment, atmospheric environment pollution SO2will reduce to0.06mg/m3, and NO2will be0.04mg/m3. Water resources demand will be3×109m3under planning scheme in central urban development planning and water resource planning. In order to provide a sufficient strategy to meet the increasing demand for waste treatment and disposal, an alternative selection process is underway to add capacity to existing plants and significantly plan the waste management. The optimal scheme, which planning scheme should be adjusted to, is3R-incineration-anaerobic digestion.Grey multi-objective model is employed to optimize PEIA system by using the quantitative result as the imput. Quantitative environmental indexes with rigid constraints are as follows:atmospheric quality SO2is0.06mg/m3, NO2is0.04mg/m3, water resources usage value is1.16×109m3, solid waste landfill value is108.9t per day. Objective functions are urbanization level is82%, GDP reaches1.633×l012yuan. According to the quantative results, Quantitative evaluation conclusions and countermeasures and suggestions for strategy implement and adjustment are put forward. The results and method cand be referred and extended in the future to develop more in-depth researches.