闽东南花岗岩侵蚀区土壤侵蚀与治理——Ⅱ.坡度和植被对土壤侵蚀的影响

土壤侵蚀量随着坡度增大而升高,但不成比例增长,在一定坡度范围内具有相对的稳定性。当坡度增大到26°时,土壤侵蚀量显著地高于10°,14°,18°和22°小区。坡面覆盖植被后,上述情况明显改变,且能使26°坡面侵蚀量降到允许范围。因此,提高植被覆盖度是控制土壤侵蚀最有效的措施。植被类型不同,其生效也有快慢之差,以草类最快,中耕作物次之,灌丛最慢。

Soil Erosion and Its Control in the Granite Eroding Area of Southeast Fujian Ⅱ.Effect of Slope and Vegetive Cover on Soil Erosion

The amounts of soil erosion with relative stability in a certain slope range in- creased with sloppe gradient,but not in propor-tion to it.When slope increased to 26,its amounts of soil erosion were much higher than that of the plots with 10°,14°,18°,and 22°.But this rule did not exist on the slope with 26° whose surface was covered by vegeta- tion and the amounts of soil erosion in these plots could be decreased to the allowable ranges.The effective practice for controlling soil rosion is to raise the degree of vegetative cov- er.The effects on controlling soil erosion occured in different velocity for various types of veg- etation,i.e.the grass family was the most rapid,the tilled crop was less and the bush was the slowest.for controlling soil evosion.