When the number of downfall days is less than 20 annually, soilerosiondegree increases along with the increase of downfall days.
当多年平均大雨日数小于20日时，土壤侵蚀程度基本上随大雨日数的增加而增加；
2
The results show that the identifying sign of soilerosion is not erosive surface but the degree of soils conservation and the change of soils thickness.
结果表明，塬区土壤侵蚀的确定依据不是侵蚀面，而是土层保存程度和土层厚度的变化。
3
Based on the analysis and study on the physical properties of karst soil in Guizhou Wujiang river basin in different type of vegetation and different degree of erosion.