基于RS和GIS的托克逊县沙化土地时空动态分析与评价

利用托克逊县1990年、1999年、2005年三期TM卫星影像数据及2007年实地调查数据,分析了托克逊县沙化土地状况、动态变化及演变机理。结果表明:2005年托克逊县沙化土地面积为804 751 hm2,占全县面积的51.54%;1990—1999年,南部区和农田区的沙质土地面积都处于扩展过程,东部封育区风蚀劣地面积处于严重扩展时期;1999—2005年南部区和农田区仍处于扩展时期,东部封育区由于采取一系列治理措施,沙质土地和风蚀劣地面积明显减少,沙化状况总体上有了明显改善。南部区气候变化是土地沙漠化形成和发展的主要驱动力,东部封育区主要受自然和人为过程的共同作用,其中气候变化是其主要驱动力;农田区的人为因素是其主要的驱动力。针对3个研究区的综合生态环境特点,分别提出了各区相应的沙化土地治理对策。

RS and GIS-based Analysis on Dynamic Changes of Desertified Land in Toksun County

In this paper,TM satellite image data acquired in 1990,1999 and 2005 and field survey data acquired in 2007 were used for the analysis on the state and dynamic changes of desertified land and its eveolution process in Toksun County,Xinjiang.The results showed that desertified land area was 804?751hm2,which accounted for 51.54% of whole Toksun County area in 2005.The sandy land area in the southern part and farmland area was in extension process and the sandification land area cansed by wind erosion in the eastern part was expanding seriously in the years from 1990 to 1999.And the southern area and farmland area of Toksun still was in extension period from 1999 to 2005.Since a series of control measures were adopted in the eastern enclosed area of Toksun,the sandy land area was reduced and began to become better gradually.Climate change was the main driving force of the desertification in the southern part.In the eastern area climate change and human factors were the driving force.Based on comprehensive eco-environment characteristics in study area,the paper put forward the corresponding desertification land control measures for each area.