草地开发与保护过程中土壤颗粒分形特征

Fractal dimension characteristic of soil particles during the grassland reclamation and protection

为加强草地土壤修复状况的定量化表征，以毛鸟素沙区天然草地与人工灌溉饲草料地为研究对象，对开发与保护过程中土壤理化性状变化及其与颗粒分形维数的关系进行了研究，结果表明，不同土壤分形维数为2．35～2．54；人工草地沙粒含量、分形维数大于天然草地．有机质含量小于天然草地。研究认为，土壤颗粒含量分形维数与粘粉粒、有机质含量呈正相关关系．与沙粒含量呈负相关关系，土壤颗粒分形维数能够定量表征土壤颗粒性状变化，可作为评价沙、退化草地土壤退化程度的定量综合指标。

In order to enhance the quantificational characteristic on the recovery condition of deteriorated grassland, the variability of soil physicochemical property and its relationships with fractal dimension of soil partiele were studied in native grassland and artificial irrigation pasture in Maowusu desert. It was showed that the values of fractal dimension was 2. 35 to 2. 54, the contents of sand and the fraetal dimension in artificial irrigation pasture were larger than those in native grassland, and the contents of organic matter was less than the native grassland. The conclusions considered that the relationships of the fractal dimension with the contents of clay and organic mater were positive correlation, the relationship with the contents of sand was negative correlation. It meant that the variability of soil physicochemical property could be indicated by the fractal dimension of soil particle, which was an aggregative and quantifieational index in evaluating the soil degeneration degree of desertification grassland.