“双评价”视角下冻融侵蚀地区生态敏感性研究

Study on the Ecological Sensitivity of Freeze-thaw Erosion Areas on thePerspective of Dual Evaluation

冻融侵蚀是我国继水蚀和风蚀之后的第三大土壤侵蚀类型,有必要在冻土侵蚀区域补充冻融侵蚀敏感性评价。共选择6个因子作为影响因素建立山丹马场冻融侵蚀敏感性评价体系,分别为:气温年较差、冻结期平均最低温度、解冻期平均降雨量、坡度、NDVI和年降水量,最终获得评价结果。结果表明:山丹马场冻融侵蚀区面积为887.78 km~2,敏感区面积为671.03 km~2,占冻融侵蚀区面积的75.58%,极敏感区面积为212.97 km~2,占冻融侵蚀区面积的23.99%;结果显示,冻融侵蚀的敏感性随着坡度的增加而增加,良好的植被覆盖有助于减少对冻融侵蚀的敏感性。

Freeze-thaw erosion has become the third largest soil erosion type in China.It is necessary to supplement the ecological sensitivity assessment method for it.A total of six factors were selected as influencing factors to establish the evaluation system of freeze-thaw erosion sensitivity in Shandan Horse Farm.They are the annual difference in temperature,average minimum temperature during freezing period,average rainfall during thawing period,slope,NDVI and annual precipitation.The evaluation results showed that the freeze-thaw erosion area is 887.78 square kilometers.The sensitive area is 671.03 square kilometers,accounting for 75.58%of the total erosion area.And the extremely sensitive area is 212.97 square kilometers,accounting for 23.99%of the total area.It indicated that the sensitivity to freeze-thaw erosion increased with the increase of slope.Good vegetation cover helps to decrease the sensitivity of the erosion soil.