土地覆被变化是反映区域气候变化和人类活动强度的重要指标,监测土地覆被变化是遥感应用的重要领域。阿姆河作为中亚重要的内陆河之一,是维系区域生态环境和经济发展的重要纽带。利用欧空局(ESA)的Global Land Cover 2000(GLC2000)和全球陆地覆被数据GlobCover的2005、2009共3期数据,以Chatly水文站点位置划分流域上下游,分析了整个流域及上游土地覆被时空变化。研究结果表明:2000~2009年阿姆河流域增加的耕地面积主要来自于自然植被和裸地,裸地面积的增加主要来自于自然植被,水体面积减少10%;在流域上游,2000~2009年耕地面积的增加约占整个流域耕地面积增加的50%,且主要发生在塔吉克斯坦和乌兹别克斯坦的山麓和平原地区,2000~2005年自然植被面积增加主要来自于撂荒的耕地和裸地,而2005~2009年自然植被面积减小主要转换为裸地,水体面积则在2000~2009年增加了153%。阿姆河流域的土地覆被时空变化分析有助于解释人类活动对该流域环境系统的影响,期望对流域水资源综合管理有所启示。
英文摘要:
Land cover change is the important indicator for the climatic change and human activity intensity, which can be monitored through remote sensing application.The purpose of this study was to quantitatively analyze the changes in land cover in the Amu Darya Basin,is one of the most important inland rivers which maintains the ecological environment and economic development in Central Asia.The whole basin would be divided into the upper reaches and lower reaches by the location of Chatly gauge station.The land cover of the Amu Darya Basin,was clipped from the Global Land Cover 2000(GLC2000)and GlobCover land cover datasets and analyzed for two different periods.Overall,the results showed,in the whole basin,the cultivated areas increased because of conversion from vegetation and bared areas,while the vegetation areas decreased from 2000to 2009.The bared areas increased because of conversion from vegetation and the areas of water body reduced by 10%until 2009.In the upper reaches,the growth of the cultivated areas accounted for about half of the new cultivated land from 2000to 2009,which occurred in the foothills and plains in Tajikistan and Uzbekistan.The vegetation areas increased because of conversion from farmland abandoned from 2000to 2005,on the contrary,decreased because of converting to bared areas from 2005to 2009.The areas of water body increased by 153%from 2000to 2009.These results will be very useful for interpretation of impacts of the human activities on the watershed environment system,enlightening integrated water resources management in the Amu Darya Basin.