不同灌溉方式下耕作土壤的分形特征研究

通过对西安北郊污灌区耕地土壤与正常耕地土壤粒径分布的分形维数分析,结果表明:土壤颗粒表面分形维数D与粒径<0.002mm颗粒的百分含量呈极显著正相关。污灌土壤的分形维数大于正常土壤,其值2.7448～2.8449之间,平均2.785。而正常土壤在2.7253～2.7746之间,平均2.755。这表明污水灌溉对土壤粒度分布和结构有重要影响,增大了土壤粒径<0.002mm颗粒的百分含量,进而影响到土壤粒径的分形分维。

Fractal Features of Cultivated Soils from Different Irrigation System

This paper presents data from both a sewage irrigated soil and a normally irrigated soil in northern Xi'an city to illustrate fractal features of grain distrubtion. Results show that there is distinct positive correlation between particle(<0.002 mm in diameter) content and the fractal dimensions of particle surface. Fractal dimensions of the sewage irrigated soil are higher than those of the normal irrigated soil. The fractal value of the sewage irrigated soil falls in between 2.7253 to 2.7746, averaging at 2.785. It is between 2.7253 and 2.7746 in normal irrigated soil, averaging at 2.755. All the results in this study suggest that sewage irrigation evidently affected the structure and distrubtion of particle size of soils and increased particle(<0.002 mm in diameter) content to control fractal value of particle-size distribution.