基于格网GIS技术的艾丁湖流域生态风险动态评估及调控机制研究

Taking Aydin Lake basin in arid area as the research object. Firstly, we use expansion module function of Arc GIS Patch Analyst, analyze landscape pattern index in different period. And Determine the critical period of ecological risk changes and ecological end. Reveal the variation process of ecological environment and ecological environmental problems. Secondly, according to the basic elements affected on the ecological risk assessment, we had constructed an technology index system of ecological risk analysis which includes the hazard indicators of risk sources, the vulnerability indicators of habitats as well as the potential loss of risk receptors.Thirdly, based on grid technology to divise ecological risk grid, than using ArcGIS spatial analysis, fuzzy comprehensive evaluation and Kriging Interpolation to evaluate the risk assessment from the four aspects of landscape risk, water resource risk, environmental risk and socio-economic risk in different period in Aydin Lake basin. Finally, using contrast method, area transfer matrix method, surface statistical analysis method and landscape pattern index method, we analyze depthly the causes and control mechanisms of ecological risk changes in the Aydin Lake Basin in different periods. Based on the results, the most important regions of eco-environmental protection in the study area were determined, and the management countermeasures of eco-environmental protection and strategies were put forward. It is significant to make a reasonable assessment of ecological risk to establish the ecological risk alarm mechanisms, minimize the risk of ecological environment and maintain the ecological function in arid inland river basin.

以干旱区典型流域---艾丁湖流域为研究对象，采用ArcGIS的Patch Analyst扩展模块功能，进行景观格局指数变化分析，确定生态风险变化关键时期及生态终点，揭示生态环境变异过程和生态环境问题。从风险源危险度、生境脆弱度及受体潜在损失度三方面构建适合流域生态风险动态分析的指标体系。采用格网化技术进行生态风险小区划分的基础上，运用空间分析技术、模糊综合评价方法和克里格插值法，对不同时期的生态风险状况从景观风险、水资源风险、环境风险和社会经济风险四个方面进行综合评估和分析，绘制艾丁湖流域不同时期生态风险等级图。采用对比法、面积转移矩阵法、面统计分析法和景观格局指数法，深入剖析艾丁湖流域不同时期生态风险变化原因，建立艾丁湖流域生态风险调控机制及管理系统，为艾丁湖流域准确、科学地选择生态保护、建设策略提供科学依据，为干旱区社会经济的稳定与可持续发展提供科技支撑。

生态环境恶化，生态资源减少，加剧贫富差距，严重危及到艾丁湖流域社会经济发展和生态安全，故本项目对研究区各个县市的进行实地调研，系统收集流域的自然环境数据、社会经济数据、生态环境状况及生态灾害数据，完成了研究区土地利用变化及景观格局研究，分析了水、土、植被及生物多样性、人类活动等要素的相互作用与联系及其生态波及效应，构建了流域生态风险分析的指标体系，采用多种方法从风险源危险度、生境脆弱度及受体潜在损失度三个方面，评价流域生态风险时空动态变化，近18年，艾丁湖流域生态风险等级变化较大，总体呈现出局部变差整体向好的趋势。其东部鄯善县的极高风险面积增加；西部托克逊县的极高风险范围得到控制，面积明显缩小；中部高昌区的极低风险面积减少，低度风险较为稳定；艾丁湖流域风险转移明显，以高度风险和极高风险面积转出最多，主要转入至高度风险和中度风险，也以极高风险面积转入最多；并分析生态风险等级转化原因及调控因子，其中起沙风天数、第一产业GDP、降水量、生境质量指数、牲畜数量、平均气温六个指标因子对艾丁湖流域生态风险变化的影响较大，在两两指标交互作用中，起沙风天数与第一产业GDP、降水量、生境质量指数、平均气温、牲畜数量的相互耦合是促使风险等级变化的主要因素；最后提出了艾丁湖流域生态风险预警、管理、调控建议，明确生态保护策略，为艾丁湖流域准确、科学地选择生态保护、建设策略提供科学依据，为干旱区社会经济的稳定与可持续发展提供科技支撑。