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本文应用20年(1981—2000年)的卫星数据反演归一化差值植被指数(NDVI),同时获取地面格网的温度与降雨数据,并分析这些数据之间的关系。基于地面的温度和降雨格网数据将研究区划分为8个气候区域,再利用NDVI数据把降雨量最少的3个气候区——区1,2,3各划分为10个等级。此外,分析这3个气候区在1983—1998年15年间的NDVI变化状况,结果显示出研究区荒漠化状况的加剧。
In this paper, normalized Difference Vegetation Index (NDVI) was retrieved from 20 years (1981-2000) satellite data. Meanwhile, the temperature and rainfall data of surface grids were obtained and the relationship between these data was analyzed. Based on the surface temperature and rainfall grid data, the study area is divided into eight climatic zones. The NDVI data is used to divide the three climatic zones with the least rainfalls - zones 1, 2 and 3 into 10 levels. In addition, NDVI changes in the three climatic zones over the 15-year period from 1983 to 1998 were analyzed and the results showed that desertification in the study area intensified.