甘肃河西地区1986—2011年水土保持生态安全格局

以甘肃河西内陆河流域为研究区域,在凸显水土保持综合措施作用的基础上,运用压力(Pressure)-状态(State)-响应(Response)模型,选取12个评价指标,用综合指数评价法对该地区的生态安全格局进行分析.结果表明:(1)研究区1986—2011年水土保持生态安全指数由0.4046(风险级)上升至0.5211(敏感级),呈现不断改善的趋势;(2)1986—2011年压力指数逐年减小,说明该区环境资源压力持续增大,基于水土保持综合措施的生态环境状态和响应指数自2001年明显增加,表明甘肃内陆河流域实施的水土保持综合措施建设具有一定的效果;(3)甘州区、金塔县、高台县以及玉门市的生态安全指数自2001年起略有下降,民勤县水土保持生态安全度虽有提升,但仍然处于恶化级.

Ecological Security Pattern of Soil and Water Conservation in the Hexi Area of Gansu,China in 1986-2011

In order to evaluate the role of comprehensive measures for soil and water conservation, we used the Pressure-State-Response model and chose 12 indices to analyze the ecological security pattern from1986 to 2011 through the comprehensive index method in the Hexi Area of Gansu, China. The results showed that: (1) The ecological security index in the target area has increased from 0.4046 (risk state) to 0.5211 (sensitive state), indicating an improvement from 1986 to 2011; (2) Environmental pressure index decreased year by year, suggesting that the environmental resource pressure increase continuously. The ecological environment status and response index have increased significantly since 2001 based on the comprehensive measures of soil and water conservation, suggesting that the construction of soil and water conservation measures has positive effects in continental river basin in Gansu province. (3)The ecological security index has declined slightly since 2001 in Ganzhou district, Jinta county, Gaotai county, as well as in Yumen district, respectively. In Minqin county, the ecological security index is improved but is still in the worse level.