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

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 freezethaw 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 freezethaw 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.