基于植被地下水关系的保水采煤研究

为研究我国西部生态脆弱矿区植被与地下水关系及其对煤层开采的约束,采用路线穿越法剖析了典型区植被随潜水埋深变化的演替规律,利用遥感获取煤层开大规模采前(2000年)植被指数,并与同期地下水位埋深建立了统计关系。结果表明:研究区天然状态下植被随地下水位埋深的增加呈现明显的分带特征,潜水埋深0~4.0 m时植被对地下水依赖性较强;综合考虑水文地质条件和植被与地下水关系,榆神矿区可划分为植被约束区、地下水约束区和无约束区3个区;矿区开采15 a后,2014年矿区地下水位明显下降和植被盖度普遍升高现象并存,这与煤炭资源高强度开采区集中在无约束区有关。生态脆弱矿区井田规划和煤层开采必须重视植被和地下水约束研究,因地制宜地制定保水采煤技术预案。

Water-preserved mining based on relationship between vegetation and groundwater

The present paper is to study the relationship between vegetation and groundwater,and the constrains on coal mining in ecologically fragile mining area.A field survey was carried out to determine the general rules of vegetation community succession,along with the increase of depth to groundwater table (DGT) in a typical region.Based on the remote sensing data and DGT data before mining,a statistical relationship between the normalized difference vegetation index (NDVI) and DGT was established in Yushenfu coal mining area.The results showed that the vegetation has a zonal characteristic as DGT increasing,and the most suitable DGT for vegetation is 0-4.0 m,the smaller the DGT,the more sensitive the vegetation.Combined with the hydrological condition and the relationship between vegetation and groundwater,the Yushenfu coal mining area could be divided into three parts:vegetation constraint region,groundwater constraint region and non-constrained region.It is in the vegetation constraint region that coal mining will cause extensive damage to vegetation.As the DGT dramatically declined,the NDVI improved in large extent by 2014,to some extent,this was due to the present mining mainly located in non-constrained region.Mine planning and coal mining must pay attention to the relationship of vegetation and groundwater in ecologically fragile mining area.