基于生态系统水平的河流风险评价

River risk assessment based on ecosystem level

现有的生态风险评价方法主要围绕特定物质或特定受体,难以用于以生态系统为对象的管理.本研究依照系统生态学与复杂系统的理论概念,采取以"生态系统服务"作为生态系统水平的风险评价终点的做法,通过量化外界压力与生态系统服务的"压力-响应"模式,建立了基于生态系统水平的生态风险评价方法,并以黄河为案例说明这一方法的应用.结果显示,黄河生态系统的保护需要重点关注中下游河段,主要的风险源为城市和农业面源,需要重点保护生境及生物类目标.结果表明所建立的评价方法可为促进基于生态系统的河流管理提供技术支持.

The current methods of ecological risk assessment （ERA） are difficult to be applied on ecosystem level, since they mainly focus on specific materials or species. An ecosystem-based river ERA method was developed depending on the concepts of system ecology and complex system theory. Distinguishingly, the method selected ＂Ecosystem Services＂ as assessment endpoints, and quantified ＂Pressure-Response＂ relationship between external stress on ecosystem and Ecosystem Services. Yellow River in China was chose as a case study. The results suggest that the most risky area of Yellow River ecosystem were middle and lower reaches; the main risk sources were urban and agriculture; and the most dangerous targets were habitats and biota. By its application in Yellow River, this method was showed to strongly support ecosystem-based river management.