Study On The Change Of Land Cover And Landscape In The East-slope Region Of Que'er Mountain

The east-slope region of Que'er Mountain is one of the ecological-fragile zones. The area climate change and human activity resulted in significant changes of land covers and landscape patterns in the study area. Studying the changes of land covers and landscape patterns, also analyzing the influence factors on the bases of 3S techniques, the multi-time RS imagine data, the current land use data, the soci-economic data, with the region survey and analysis software. the results showed that:(1) The cropland, woodland, grassland, road, river, lake, snow and bare land are the main land cover types in the study region. The woodland ranked first at all the three times, followed by the grassland in 1975 and 1994, the bare land got to the third place while it surpassed grassland ranked second in 2003. By contrast, the areas of river, cropland and lake were small. During the 28a, the change of bare land and snow were the most obvious, especially the change of bare land. The integrated index of land cover suggested that the eco-environmental quality was degraded sharply. The degraded extent per year from 1975 to 1994 was 0.98 and from 1994 to 2003 was 0.78. The degraded extent was reduced gradually. The change intension of snow was greater than all others, while the area of bare land increased most.(2) The Landscape pattern indexes showed that, during the 28 years the landscape pattern underwent an obvious change. The landscape diversity indexes of three periods were 0.6261, 0.4465, 0.4924, respectively; SHEI educed(minimize) from 0.3011 to 0.2368, moreover the SHEI of 1994 slightly smaller than that of 2003, just reached 0.2147; D rise(increase) from 10.3556 to 14.1137. Isolation of bare land was relatively high, wood land and Cropland were comparatively low. Fragmentation was marked by a continuous increase from year to year in the study area of bare land, woodland, grassland and snow, but that of cropland and lake decreased gradually year-to-year. Meanwhile, the study of isolation showed that isolation index changes of snow and bare land were most prominent(3) The analysis of influence factors showed that, climate, elevation, road and river all have certain effects upon landscape distribution. The reduction of snow area was mainly effected by continually temperature increase and changeful precipitation. Along with elevation increase, the acreage proportions of woodland and grassplot dwindled, while the acreage proportions of bare land and snow enhanced. The proportions of two main land patterns-woodland and grassplot, reduced as fast as the distance to river increase, while the proportions of bare land and snow increased. The result of buffer analysis of road was similar to that of river.