青海高原东部河湟谷地生态风险评价——以海东市为例

以位于青海高原东部河湟谷地的海东市为研究区，在土地利用变化分析的基础上构建生态指数，利用移动窗口法获得区域空间连续的生态风险指数，再结合GIS空间分析获得与土地利用空间尺度相一致的生态风险评价结果。结果表明：1999-2009年，青海高原东部农业区土地利用变化明显，有林地、灌木林地、建设用地面积迅速增加，耕地、水浇地、草地面积持续大幅减少，土地利用变化区域占总面积的42.04%；生态高风险区面积增加显著，增长率达27.11%，主要位于未利用地和建设用地区域；生态中风险地区面积减少，主要位于旱地、水浇地、草地分布区域；生态微、低风险区域主要位于林地、灌木林地区域。

Land Use Changes and Ecological Risk Assessment in Eastern Qinghai Plateau: a case study in Haidong,Qinghai, China

We selected Haidong city in eastern Qinghai Plateau as study area. Using land use maps derived from remotely sensed data, the spatial-temporal changes of land use were analyzed from 1999 to 2009.Then, the regional continuousecological risk index was calculated using moving window method.The result showed that regionalland use had changed obviously from 1999 to 2009, whichaccounted for 42.04% of the total area. Forest land, shrub landand construction land increased rapidly during study period, while non-irrigated land, irrigated land and grass land continuous reduced. The high risk land increasedobviously during study period. It accounted for 27.11% of the total area where the main land use types were unused land and construction land. The medium ecological risk land decreased during study period where land use types were non-irrigated land, irrigated land, and grass land. In low and micro risk zone, the main land use types were forest land and shrub land. The results supplieddecision support for regional ecological construction in eastern Qinghai Plateau. The study also proposed effective methods for calculating regional continuousecological risk.