大柳塔煤矿采煤塌陷对土地沙漠化进程的影响

Effect of coal mining collapses of the Daliuta coal mine on land desertification

陕西神木大柳塔县地区煤炭资源的开发不可避免会产生地面塌陷、地裂缝、地下水位下降等矿山环境地质问题,地面塌陷是否会加剧土地沙漠化成为研究的热点问题。调查表明20年间整个研究区和其中的主要矿区土地沙漠化呈现出重度沙漠化土地逐年减少、轻度及非沙漠化土地面积逐年增大的一致演化趋势,采煤塌陷区土地沙漠化没有出现加剧的现象。通过4处采煤塌陷区及2处煤矿未开采区土壤垂向剖面研究,地表植被类型及覆盖度、植被根系垂向分布、土壤粒度、含水率、地下水位之间等关系表明,采煤塌陷对土地沙漠化进程没有明显的影响。年均415mm的降雨量基本满足采煤塌陷区沙生植被正常生长所需水份,其结论为该地区大规模煤炭资源开发土地沙漠化防治提供了科学依据。

Exploitation of coal resources in the Daliuta area, Shenmu, Shaanxi, inevitably causes the problems of mine environmental geology such as land collapse, ground cracks and lowering of the groundwater level; thus whether land collapse will intensified land desertification becomes a hot topic. Investigation indicates that during the last 20 years the land desertification in the whole Daliuta area and main mining areas therein shows a consistent evolutionary trend of gradual decrease of severely desertified lands and gradual increase of shghtly desertified and non-desertified lands, and the land desertification in coal mining collapse areas has not been engraved. The authors studied the relationship between vegetation species and their covered rates, soil granularity, water content, vertical distribution of vegetation root systems at the vertical soil profiles in four coal mining collapse areas and two non-mining areas in the coal mine and conclude that coal mining collapses have no significant effect on land desertification and that the annual average rainfall of 415 mm may in the main meet the requirement for the moisture content for the normal vegetation growth in coal mining collapse areas. Such a conclusion provides a scientific basis for the prevention and control of land desertification during large-scale coal resources exploitation in mining areas.