Remote Sensing Investigation of Aeolian Desertification in Longyangxia Reservoir Region in Recent 30Years

In this paper,satellite images interpretation and GIS analysis were used to obtain the data of aeolian desertification land in Longyangxia reservoir region in 1975,1989,2000 and 2005.The results showed that the variation of total area of aeolian desertification land experienced two stages from slowly development to preliminary reversal in the past 30 years;some severe desertification and extremely severe desertification had been reversed since 2000;The aeolian desertification land was mainly distributed in the Talatan and Mugetan;Reversal was mainly from severe and extremely severe aeolian desertification lands to moderate and slight aeolian desertification lands.Though the precipitation in the study region increased from 1975 to 1989,the aeolian desertification land grew because of the impact of human factors.From 1989 to 2000,because of the climate condition of warming and drying and overgrazing,severe and extremely severe aeolian desertification lands developed continually;After 2000,the present situation of aeolian desertification had been reversed because the climate condition tended to warn and wet and the government took a series of ecological environment protection and rehabilitation measures.