喀斯特地区不同土地利用类型土壤侵蚀特征研究

探明喀斯特土壤侵蚀特征,对石漠化过程研究具有重要意义.采用野外调查与室内试验相结合的方法,通过样品分析、直剪试验与模拟冲刷试验,研究了典型喀斯特地区不同地类的土壤侵蚀特征.结果表明:(1)该地区灌丛地土层厚度大于林地和坡耕地的土层厚度;(2)该区土壤紧实度由小到大的顺序为:坡耕地<灌丛地<林地;(3)在土壤崩解速率及土壤冲刷模数方面,坡耕地＞灌丛地＞林地.整体上,坡耕地土壤侵蚀特征表现出极强的差异性,灌丛地与林地间差异性不显著.因而保持与恢复喀斯特地区植被、减少耕作活动是防治土壤侵蚀和控制石漠化的主要途径.

Characteristics of Soil Erosion for Different Land Types in Karst Areas

Discovering soil erosion characteristics in karst area is significant for studying the processes of rocky desertification. By combing field investigation with experiment and through sample analysis,direct shear test,and simulation scouring test,soil erosion characteristics for different land types in the typical karst area are studied. Results are as follow:Soil thickness on shrub land is greater than forest land and cultivated slope land. Soil compactness degree on cultivated slope land is less than shrub land and on shrub land,less than forest land. By soil slaking rate and scoring modulus,the order of the land types is cultivated slope landshrub landforest land. On the whole,soil erosion characteristic on cultivated slope land has a significant difference and there is no significant difference in soil erosion characteristic between shrub land and forest land. Therefore,protecting and recovering vegetation in karst area and reducing cultivation activities are the main approaches to protect soil and control rocky desertification.