| In Shanghuang experimental region of Guyuan,Ningxia,the fractal features of soil particle size distribution of bush forest land,farmland,natural meadow,orchard and artificial meadow have been studied.And the relationships between fractal dimension of soil particle distribution and selected soil properties have been discussed.The results show that: ① there is some relationship between soil sand content and its fractal dimension;contrary to the former,there is remarkable quantitative relationship between soil clay content and its fractal dimension,that is to say that the more the contents of clay,the more fractal dimension and the higher degree of evolution of soil;② with the longer of bush forest land its clay content and fractal dimension becomes more,while orchard is different at all;soil fractal dimension under different land use tends to natural meadow>farmland>bush forest land>orchard>artificial meadow;③ there exists remarkable quantitative relationship among soil clay content,its fractal dimension and CEC,that is to say that soil fractal dimension can be used as a comprehensively quantitative index to evaluate the evolution of soil properties;soil fractal dimension can mainly be affected by soil sand content,soil clay content and CEC. |