生态承载力环评：研究进展·存在问题·修正对策

Research Advances,Defects and Countermeasures for Environmental Impact Assessment of Ecological Carrying Capacity

环评技术标准的科学性和完备性是决定环评文件质量及应用价值的关键,但长期以来生态承载力环评技术一直是环评标准体系中最薄弱的环节.通过回顾国内外生态承载力研究发展历程,解析生态承载力概念和内涵,介绍自然植被净第一性生产力评估法、生态足迹法、资源供需平衡法与综合指数法等常用生态承载力评估方法的评价原理、技术流程,指明上述各类方法片面注重"承载力"极值的量化或超载与否的评估,但却忽视人类经济社会发展产生压力指标与区域自然承载能力对应关键指标在指标类型、大小及空间上的矛盾对立性研究,以致评价过程不清晰、评估成果对于优化区域人地关系的参考价值十分有限.在此基础上结合我国生态承载力环评制度、技术导向及研究实践状况论述,指出现有生态承载力环评技术标准存在技术方案不完整、评价内容项目针对性弱、评价空间尺度与项目影响范围不匹配等问题,以此为前提,提出重新界定规划环评领域生态承载力概念,以提升科学性与实用性为目标革新生态承载力环评技术框架体系,针对项目生态压力类型及空间格局确立生态承载力评价内容,充分利用3S等新技术开展生态承载力定量化评估等修正对策建议.研究旨在为开展生态承载力评估技术革新与探索研究提供借鉴.

The scient if icity and completeness of EIA technical standards determine the qual ity and appl ication value of Environmental Impact Assessment （EIA） documents. EIA technology for ecological carrying capacity （ ECC） has always been the weakest section in the EIA technology standard system. Based on detailed investigation into research advances in ECC,the concept and connotation of ECC were analyzed. The commonly used technical methods to evaluate ECC at home and abroad,including ‘ net primary productivity assessment of natural vegetation’,‘ecological footprint’,‘supply and demand balance’ and ‘ comprehensive index’,were introduced with their according assessment theories and accounting procedures. The methods focus on accounting the extreme value of ECC or confirming whether overloading has occurred or not. However, the key corresponding opposition indices between the pressure exerted by human economic and social development and the carry capacity possessed by nature, as w e l l as th e ir characters, size and spatial ly distr ib uted pattern were neglected. Research results without clear assessment of these methods cannot offer valuable suggestions for promoting the coordination of humans and nature. By thorough analysis of EIA regulations, technologies and methods of ECC and th e ir applications in practice in China, problems were revealed, such as incomplete technical framework, low correlation between assessment contents and EIA plans or p rojec ts, spatial scale of E IA not matching influence range of E IA plans or p rojec ts, etc. Subsequently, the concept of ECC in E IA was re define d, a new E IA technical framework of ECC was proposed fo r enhancing rationality, practical value and operabi lity of E IA re su lts, and suggestions were offered, in c lu d in g： the E IA contents should be decided according to pressure types analysis about the assessed plan or p ro je c t, and 3S and other new technologies should be used to carry out quantitative assessment of ECC. The research scheme can provide references for technology innovation about ECC assessment exploration.