Abstract: Like other inland river basins, land desertification is one of the most important problems of eco environment in the Heihe river basin. The land desertification status and developing trend are analyzed in this paper. The results indicate that the degree and process of land desertification are markedly varied in different regions of the Heihe river basin. The desertification land areas in the Gaotai, Linze, Jinta and Ejin counties have reached about 54.90%~64.20% of each total land area, and the shifting sand dune areas in the Mingle, Sunan, Gaotai, Jinta and Ejin counties reached 22.81%~35.07% of the desertification land area. The modern desertification developed quickly in the middle and lower reaches of the Heihe river basin. In late years, because of the largely administering action of desert, the developing rate of land desertification has been reduced in the middle reach, such as in the Zhangye and Jinta counties, of which the rate was reduced by 2.40% and 5.90% respectively. After 1990, the desertification developing rate in the Jinta and Zhangye counties is 0.5% and 0.09% respectively. However, in the lower reach, the desertification was developed speedily still, and the desertification rate in the Ejin Banner reached 5.60%. Affected by the climate drying and warming trend, the exploitation of water resources and the potential desertification environment of soils, the developing trend of land desertification in some regions in the Heihe river basin would be intensified in the future. The human activities may take an important play for changing the trend of the land desertification. In order to reduce the developing rate of desertification or reverse the desert process, rational and thrifty utilization of water resources in the entire basin is the key factor.

Key words: Heihe river basin, desertification, developing trend