河流生态系统修复阈值界定指标体系初步构建

生态阈值存在于各种生态系统中，在查阅国内外相关文献的基础上，通过对生态阈值的理论研究及实践应用进行总结分析，指出生态阈值在河流生态系统中的研究不足之处。通过分析阈值在河流生态修复中的重要性，从新的角度探讨提出河流生态系统修复阈值概念，是依据河流生态系统自然属性和河流功能以及区域社会经济发展的需求界定退化到何种程度的水生态系统需要进行修复。通过对指标体系构建原则、筛选方法及阈值计算方法的总结，提出河流生态系统修复阈值确定技术路线，采用频度分析法和理论分析法相结合，从影响河流修复的6大要素（物理结构、水文条件、水质状况、水生生物、河流功能和社会经济）初步构建了河流生态修复阈值界定指标体系及阈值计算方法体系，为下一步河流生态修复阈值指标体系的定量筛选与阈值计算奠定了基础。

Initial establishment of threshold defined index system on river ecological restoration

Ecological threshold exist in all kinds of ecological systems. Deficiencies on ecological threshold research in river ecological system were pointed out based on reviewing relevant literatures and analyzing theory researches and practices on ecological threshold. By analyzing the importance of threshold in river ecological restoration, river ecological restoration threshold concept which was to define to which degradation extent should the river ecological systems need to be restored according to river ecosystem natural properties and functions of river and needs of regional socio-economic development. Through summarizing index system construction principles, screening methods and threshold calculation methods, this paper put forward the technical route of river ecological restoration threshold. Combining frequency analysis method with theory analysis method, index system and threshold calculation method system of river ecological restoration threshold were initially built on six elements (physical structure, hydrological conditions, water quality, aquatic organisms, stream function and social economic) which influenced river restoration. This laid the foundation for next quantitative screening and threshold calculation of river ecological restoration threshold index system.