Studied On The Influences Of Coal Mining Collapse On The Soil Water Dynamic Of Dune

The surface collapse in the coal mining worked out area leads to the influence of the surface ecological environment. Through researching the soil water content of the fixed dune that had collapsed two years ago, the study showed the influences of coal mining collapse on the spatiotemporal changes of soil water dynamics. The research provides the basis gist for making use of the soil moisture for reasonable and for the technique measure of reconstructing land ecological system.As to the analysis result, it is can be seen that the sand soil water content in the depth of 0cm to 100cm is free from the influence of the groundwater replenishment in the research area. Both of the sunken area and the un-sunken area soil water content change are related to the rainy season and rainfall. It was lowest in June, and went up with raining season coming in July. Then it reached the maximum in August and gradual decreased in September. The trend of vertical changes of soil water content in both sunken area and un-sunken area are accordance, that their average value increase with the depth. The average sand soil moisture of un-sunken reaches a maximum at 80cm depth, and has a little bit descent below. It reaches a maximum at 100cm depth in sunken area. Below the 80cm, the soil water content of sunken area is bigger than un-sunken. The soil moisture of dune slope of windward and the dune top is lower than other part of the dune. But the different is not evidence as the influence of the height of the dune and the influence of the vegetation.It is shown that the soil water content between 0cm to 100cm depth of fixed dune in both sunken area and un-sunken area haven't had an obvious difference after the surface collapse two years. The influence of coal mining collapse on water spatiotemporal changes in the sand soil is lower.