重要生态功能区生态退化诊断理论、思路与方法探析

摘要

准确诊断区域生态系统退化程度并明确生态退化驱动要素是高效实施生态修复的前提和基础。基于生态退化诊断主要理论，指出生态退化是相对概念，确定生态退化诊断参照系与诊断指标是生态退化诊断的必要步骤。生态退化诊断参照系判别结果显示区域生态系统退化诊断不应关注某一特定历史状态，应更多着力于研究区域生态系统退化的时间动态与空间差异，从而保障诊断研究的客观性。在此基础上，为凸显重要生态功能区生态退化与生态功能的密切关系以及生态系统退化的综合性，从生态功能维护力、生态自我恢复力和生态压力3个方面提出了生态退化诊断思路和诊断流程，并构建了生态退化诊断指标体系。为体现生态退化诊断的综合性和层次性，将单项分析与综合分析相结合，构建生态退化程度综合指数进行综合诊断，为提高生态退化诊断的精确性提供了理论指导和技术支持。%Precise diagnosis of degradation of a regional ecological system by degree with its driving factors specified is the precondition and basis for efficient implementation of ecological restoration. Based on the prevailing theories for diagnosis of ecological degradation, it has been pointed out that ecological degradation is a relative concept and that determination of a reference system and an index system is an essential step for the diagnosis. The determination of a reference system for the diagnosis shows that for diagnosis of degradation of a regional ecosystem should not focus on just one specific historical sta⁃tus, but rather pay more attention to temporal dynamics and spatial variability of the degradation, so as, to ensure objectiv⁃ity of the diagnosis. On such a basis, to highlight the close relationship between ecological degradation and ecological func⁃tions as well as the comprehensiveness of ecosystem degeneration in important ecological function areas, a train of thought and a flowchart for diagnosis of ecological degradation from the perspective of ecological maintaining ability, ecological self⁃restoration ability and ecological pressure have been brought forth, and an index system for the diagnosis has been set up. In order to embody the comprehensiveness and hierarchy of ecological degradation diagnosis, single factor analyses, in⁃cluding ecological function maintain index ( EMI ) , ecological resilience index ( ERI ) and ecological pressure index ( EPI) , is combined with comprehensive analysis, and an integrated index for determining ecological degradation is set up for comprehensively diagnosis degree, which may provide some theoretical guidance and technical support for higher preci⁃sion of the diagnosis of ecological degradation.