应用数值分析试论黄土丘陵区侵蚀土壤的发展规律——以固原县为例

侵蚀土壤是水土流失历史过程中的一面镜子,在一定程度上,它反映过去的流失程度,也反映目前土壤的肥力水平.我国黄土丘陵区侵蚀土壤分布之广,侵蚀程度之烈,是世界上罕见的.研究侵蚀土壤的发展规律及其与侵蚀因子间的相互关系,对合理利用土地、制定保土措施有一定的指导意义.本文以宁夏固原县侵蚀土壤调查资料为例,并应用数值分析的结果,探讨黄土丘陵区侵蚀土壤的发展规律,为防治水土流失提供科学理论依据.

DISCUSSION ON THE DEVELOPMENT OF ERODED SOILS IN THE LOESSIAL HILLY REGION BY MEANS OF NUMERICAL ANALYSIS

The eroded soils are widely distributed in the Loessial hilly region of China, which is the direct result of water and wind erosion. As the result of development of the eroded soil, the surface layer of a soil became thin, infertile, and even barren finally. Therefore, it is greatly harmful to agricultural production. The eroded soils are generally classfied by the thilcness of eroded soil or that of soil layers remained. The principal components and stepwise discriminatory analysis are based on the data from the field observation and numerical coding. In this study, four important factors(erodibility, slope, intensity of land utilization and damage from unreasonable land utilization) which influenced soil erosion were used as variable for calculation.