西藏地区风沙土地主要分布于山地之间的盆地和河谷区的河漫滩、河岸阶地和山口处的冲洪积扇与山地上。自藏东南至藏西北大体处于三大自然带,讨论了不同自然带风沙化土地类型和特点及其差异。据考察,该区现代土地风沙化状况分布格局是由自然因素引起的自然过程和人为因素引起的人为加速过程组成。所以,未来发展趋势主要取决于两种因素决定的结果。

The wind-sand impacted lands in Tibet Autonomous Region are mainly distribrted in the inter-mountain basin and on river beaches,river terraces and on alluvial-deluvial fans and hill slopes at mountain pass in river valley.There are three natural belts from the sortheast to the nothwest of Tibet and there are remarkable differences in wind-sand impacted lands Patterns and their characteristics in each belt.The southeast part of Tibet belongs to sub-humid forest-meadow steppe belt in Alpine temperote-sub-tropical zone and its surface is mainly composed of vegetated and semi-fixed dunes.The south'part of Tibet is located in the semi-arid steppe of alpine temperate zone and semi-fixed,semi-shifting and partially mobile dunes are the main duneforms.The north and the northwest parts of Tibet are situated in the arid desert and extremely arid desert of alpine temperatr-frigid zone and mobile dunes occupy the dominant percentage of duneforms,and there are some existence of a few vegetated semi-fixed dunes and bush vegetated sand mounds along river courses,lake shores and in the low-lying areas with high underground water table.It is concluded on the basis of the field invvestigation and the study in recent years that the contemporary wind-sand impacted lands and their distributive situation in Tibet are related to the physical Process caused by natural factors and to the human accelerative process caused by human factors.Consequently,the developmental trend of wind-sand impacted lands in future in Tibet Region will be determind by the impacts of natural factors and human factors in coming years.