干旱区内陆河流域绿洲水土资源生态风险动态研究

Dynamic Research on Ecological Risks of Soil and Water Resources for the Oasis in Arid Inland River Basin

水土资源是相互作用相互制约的有机整体,贯穿地区社会、经济、环境协调可持续发展的主线。石羊河为西北干旱区典型缺水流域,依托该流域发展的绿洲是人类生产生活的集聚地,存在着特殊而敏感的人与环境关系。以武威市为例,通过构建LUCC生态风险模型,借助GIS技术与相关统计方法揭示其土地利用生态风险动态及空间变化;参照石羊河水资源公报与武威市统计年鉴(2003—2009年),建立水资源利用生态风险识别评估体系,对比研究了不同时段的水资源利用动态风险。结果表明,研究期内武威市土地覆被景观生态风险主要集中在耕地、牧草地和未利用地,且分布面积较广;各区县土地利用综合风险指数均有所增加,土地利用格局的变化产生了一定生态风险;2003—2009年武威市水资源利用生态风险等级显著提高,各地区需结合自身实际情况,采取措施应对水资源生态风险变化。

Water and soil resource is an organic system of interactions and restrictions with each other,which is the main line throughout the coordination and sustainable development of regional society,economy,and environment.Shiyang River basin is a typical area lack of water resources in northwest arid zone.Oasis cities relying on the basin are the agglomeration centers of human production and life,and have a special and sensitive human-environment relationship.By taking Wuwei City as an example,and constructing LUCC ecological risk model,the dynamic and spatial changes in the ecological risks of land utilization were revealed with the help of GIS and statistical method.Besides,identification and evaluation system for the ecological risks of water utilization were established by referring to the bulletin of water resources and statistic yearbook（2003—2009） of Wuwei City and the trends of the changes in water utilization risk were analyzed comparatively.The main conclusions are as follows： the ecological risk of land use cover in Wuwei City mainly concentrated on cultivated land,grassland and unused land which totally account for a greater percent in the whole area;the integrated land use risk indexes for the counties and districts of the city increased during the research period and changes of land use patterns produced a certain degree ecological risk;the ecological risk level of water resources utilization from 2003 to 2009 rose significantly,and the counties and districts should take corresponding countermeasures to deal with the change in ecological risks of water and soil resources.