More than 90％ of water resources in Xinjiang originate from mountainous areas.As one of the important drives leading to hydrological and ecological change,land use change may influence canopy interception,evapotranspiration and percolation and eventually cause flood-drought disasters and ecological problems.During past decades,climate change and human activity have deeply changed mountain environment in Xinjiang.However,the direction and magnitude of land cover change were not clear in the three mountain areas (i.e.the Altai Mountains,the Tianshan Mountains and the Kunlun Mountains).In this paper,land cover change of mountainous regions in Xinjiang were explored qualitatively and quantitatively.Land cover types transition were extracted and analyzed from 2000 to 2010 based on the land cover maps of 1990,2000 and 2010;vegetation change were also examined from 1982 to 2013 with the help of Geographic Information System (GIS) and Mann-Kendall non-parametric test method,based on GIMMS 3 g NDVI data preprocessed with the monthly mean,standardized anomalies and trend preserving prewhitening methods.Then,the spatial relationship between land cover type transition and vegetation condition change were discussed.In addition,qualitatively change were observed.Land cover classes did not changed in 99％ of the area.But in more than 30％ of mountainous area,NDVI have significantly changed.The area with vegetation degradation accounts for about 30％,25.27％ and 33.69％ in the Altai,the Tianshan and the Kunlun mountains respectively,while 4.07％,18.26％ and 19.83％ area of the vegetation have improved,respectively.Vegetation degradation mostly occurred in the low elevation area with strong disturbance of human activities;the grassland and sparse grassland are main land cover types which have degraded.The degraded grassland area accounts for 22.18％ of the total grassland area in the Altai Mountains;the degraded areas of grassland and sparse grassland account for 18.88％ and 10.74％ of their total area in the Tianshan and the Kunlun mountains,respectively.Analysis from qualitative and quantitative views could supply an insight of land use and cover change of mountains in Xinjiang,which should be essential and useful in evaluating the ecological and hydrological responses of climate change and human activities.%山区是新疆主要的产流区,山区土地覆被变化对新疆经济发展和生态环境安全具有重要意义,但新疆山区的土地利用整体变化情况尚不太清楚.该文基于新疆1∶10万土地覆被类型数据和GIMMS 3 g植被指数数据,综合运用GIS空间分析和月平均、距平和趋势保留预置白处理方法及Mann-Kendall非参数趋势检验方法,提取与分析了新疆三大山区在1990-2010年土地覆盖类型转化和1982-2013年的植被覆盖变化情况,尝试从2个维度分析新疆山区土地覆被变化情况,探讨了植被覆盖的显著变化与土地覆盖类型之间的空间关系.结果表明:1)以土地覆盖类型转化为标志的新疆土地覆被质变情况发生比例很小,99％的土地覆被类型没有发生变化;2)新疆三大山区中均有大于35％的面积植被状态发生了不同方向上的显著变化,阿勒泰山区植被退化30.38％,植被改善4.07％,天山山区植被退化25.27％,植被改善18.26％,昆仑山山区植被退化33.69％,植被改善19.83％;3)发生退化的区域主要分布于人类活动干扰较强的低海拔及山前地区,且主要以草地和稀疏草地为主,阿勒泰山区草地退化面积占到总面积22.18％,天山山区稀疏草地和草地退化面积占到总面积18.88％;昆仑山区植被稀疏草地和草地退化面积占到总面积10.74％.研究结果说明从质变和量变二种角度的分析能够提供对山区土地覆被变化提供更全面的认识,在分析土地覆被变化的生态水文响应时应当给予综合考虑.
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