中文摘要：

以位长江上游的大渡河流域的壤塘县为研究区。基于TM遥感影像,采用面向对象与目视解译相结合方法,提取1989年和2009年两个时期亚高山针叶林的空间分布,并对两期数据叠加分析,查找出其演替发生的类型和空间位置,作为因变量样本。同时,以GIS技术为支撑,基于DEM和专题数据,提取高程、坡度、坡向正弦、坡向余弦、地表曲率、距居民点距离、距耕地距离和距道路距离8个自变量,使之与亚高山针叶林空间演替样本进行Logistic回归拟合,计算各自变量的贡献率和演替发生概率在空间上的变化特征。结果表明：亚高山针叶林向草甸演替的过程中,距居民点距离和距耕地距离两个变量贡献较大,距居民点距离减小1个单位,其转变为草甸的概率将增大1.15倍。在亚高山针叶林向落叶阔叶灌丛演替的过程中,坡向正弦和距居民点距离贡献较大,其发生概率随坡向朝北程度的增大而增大,增大1个单位,概率将增大1.2倍。对亚高山针叶林空间演替特征的定量分析可以为亚高山针叶林的保护与恢复提供科学依据。

英文摘要：

The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation and visual interpretation,and then the overlaying analysis of these data was conducted.The type and spatial location of succession were discovered and served as the sample of dependant variable.Meanwhile,supported by GIS technology and based on DEM and thematic data,the eight variables including altitude,slope,sin and cosin of aspect,curvity of land surface,and distance to residential area,cultivated land and road were extracted served as the sample of spatial succession of subalpine coniferous forests to fit Logistic Regression,and then the contribution of each independent variable as well as the spatial property of the occurrence probability of succession was calculated.The results suggested that,during the succession of subalpine coniferous forests to meadow,the closer to the residential area and cultivated land,the greater the contribution to succession is.In particular,when the distance to the residential area decreases by one unit,the probability for its conversion to meadow will be increased by 1.15 times.During the succession of subalpine coniferous forests to deciduous-broadleaved shrubs,the sin of aspect and distance to residential area contribute more,and the probability of succession increases with increasing degree of northwardness,i.e.when the degree of northwardness increases by one unit,the probability will be increased by 1.2 times.The quantitative analysis of spatial succession property of subalpine coniferous forests will supply scientific basis to the protection and restoration of subalpine coniferous forests.