Abstract: Understanding the ecological functions of soil is one of the fandamental prerequisites for the reasonable utilization of soil resources.In mountainous area,ecological functions of soil exhibit a characteristic of remarkable vertical differentiation, and this is the starting point of investigating mountainous soil ecosystem and exploiting and utilizing mountainous soil resources.In this paper, an elementary approach to the ecological functions of soil and their characteristics of vertical differentiations in Gongga mountain area is made.

Key words: Larix chinensis, Population, Size-class structure, Life table, Survival curve, Population dynamics