A Study Of Different Sandy Land Soil Water's Regular Changing Patterns On Wulanbuhe Desert

This study,grounded on Wulanbuhe Desert where the author made six experimental bases on the moving sands,one on the half-fixed ones and another on the fixed ones.was conducted from early May till late September in 2004,during which the author first made on site researches and experiments on different types of sandy land in terms of soil structures,vegetation root systems as well as soil water dynamic states,and then ,by taking soil samples,made an indoor experiment on the soil physical properties and water contents. Accordingly.the author gets the following results:I) the sand dune of the moving sands is made of traveling aeolian sandy soil and its surface is of flat clay soil (the lowand around by sand dune);the profile soil structure of half -fixed and fixed sands is very complex—an interplay of sandy soil and clay soil:Mechanical soil elements and their physical properties are much different in different geomorphology and they have regylar changing features.II) Different sands soil water dynamic changes are mainly effected by soil properties/vegetation fonns,distribution of underground root system,rainfall,evaperation and depths of underground water.III) There are three levels of space changes in moving sands soil watendry sand layer,active soil moisture layer and stable soil moisture layer;in terms of time,the water content in the same sandy layer is lower in April and May than in June ,July,August and September;the water content in different windward slope parts is like this:the top of slope