基于RS/GIS的玛纳斯河流域土壤空间分布的分形与分维

The Fractal and Fractal Dimensions of Manas River Valley Soil Spatial Distribution Based on RS/GIS

分形理论在描述不规则几何图形方面的优越性十分显著。基于分形理论,对玛纳斯河流域土壤空间分布的分形性质进行了定量研究,在建立了玛纳斯河流域各土壤类型斑块周长-面积定量关系的基础上,进一步计算出各土壤类型在空间分布上的分维数与稳定性指数,得出以下结论:玛纳斯河流域各土壤类型斑块的周长-面积双对数关系显著,即玛纳斯河流域土壤空间分形结构客观存在。各土壤类型图斑的分维数存在差异,分维数最大的是草甸盐土,为1.7091,最小的是灌耕石灰性草甸土,为1.0524,分维数空间分布的总体趋势是由南向北逐渐变小。研究得出的各土壤类型的稳定性指数中,灌耕石灰性草甸土的稳定性指数最高,为0.4476,盐化灰漠土稳定性指数最低,为0.0223,两者之间的极差为0.4253。这些数据为定量描述玛纳斯河流域土壤信息提供了有用的参数,为揭示土壤系统内部的复杂性研究提供了一定的依据。

The fractal theory has advantages in describing the irregular geometry. Based on this theory, this paper researched the soil spatial fractal of Manas River Valley. The circumference- area quantitative relationship of different types of soil patches was established, and their fractal dimensions and stability indices were calculated. Some results were that there was a significant double logarithmic relationship between the circumference and area of soil patches, which indicated the existence of the soil spatial fractal in Manas River Valley. The fractal dimensions in different types of soil patches were different, declining gradually from south to north. The dimension of meadow saline soil, 1.7091, was the largest, and that of irrigated farming meadow calcareous soil, 1.0524, the smallest. While the stability index of irrigation farming meadow calcareous soil was the highest as 0.4476, and that of gray desert soil the lowest as 0.0223. The above parameters described quantitatively the soil characters in the Manas River Valley and provided reference for studies on the inner complexity of soil systems.