在分析流域生态风险发生机理的基础上,根据风险评估框架,从风险评估三要素风险源-生境-受体出发,构建了危险度-脆弱度-损失度流域生态风险评估技术体系,主要包括综合模型的构建、指标体系选取、等级体系划分与评估单元确定等内容,并以太湖流域为例进行实证分析,结果表明:太湖流域生态风险整体以中等风险为主,呈升高趋势,与2000年相比,2008年高、较高生态风险所占面积比分别增加了0.39％和S％.实证分析基本验证了模型及方法的科学性和可操作性.%Reference to the previous research results about ecological risk assessment, the paper firstly considered the interaction mechanism and the relationship among each ecosystem from the watershed ecosystem perspective, and then studied the content and features of ecological risk assessment about typical watershed. Secondly, according to the basic elements (risk sources, habitat and effect) affected on the ecological risk assessment, base on an overall consideration of many risk sources, risk factors, multi-endpoint and ecological receptors coexistence, we had constructed an technology system which includes the hazard indicators of risk sources, the vulnerability indicators of habitats as well as the potential loss of risk receptors. The main parts of system included comprehensive model building, index system selection, level division and assessment unit determination. Finally, using the ArcGIS technology and assessment model, we evaluated the time-spatial evolution character of Taihu Lake watershed and determined the status and trends of ecological risk development based on the assessment results. The results indicated that most ecological risk of Taihu watershed were medium level and increased gradually. As compared with 2000year, the percentage of high and higher risk region had increased by 0.39% and 5% separately in 2008 years. The empirical analysis verified the scientific and feasibility of the models and methods.
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