靖边县水源地区域地下水环境变化研究

靖边县饮用水源多为地下水,地下水环境的变化严重影响着当地供水量。为了进一步厘清研究区地下水环境在时间和空间上的变化情况及其影响因素,利用统计学及水文地球化学方法,对研究区地下水位统测结果和90组地下水水样检测结果进行分析。结果表明:1995-2017年研究区内大部分地区地下水位显著下降,在郭家庙等地已经形成较大规模的降落漏斗;地下水中TDS浓度明显增加;部分区域TDS、NO3-超标,尤其是农灌区常年施用含氮肥料导致地下水中NO3-浓度超标且范围不断扩大。因此,当地应及时控制地下水开采量,采用新型灌溉、合理施肥等措施来减缓地下水位的持续下降与水质恶化。

Groundwater environment change of water source area in Jingbian County

The main drinking water source in Jingbian County is groundwater, and the groundwater environment changes seriously affect the water supply amount. In order to clarify the changes in the groundwater environment in the view of time and space as well as the influencing factors, statistical and hydrogeochemical methods were used to analyze the results of groundwater level investigation and the 90 groundwater samples on the study area. The results showed that the groundwater level in most of the study area decreased significantly from 1995 to 2017, and a large-scale falling funnel has formed in Guojiamiao and other places. The concentration of TDS in groundwater increased significantly. Furthermore, TDS and NO^-₃ in some areas have exceeded standard requirements. It is found that the application of nitrogenous fertilizers has led to the excess of NO^-₃ in groundwater and the influence scope keeps expanding in the irrigation area. Therefore, reasonable measures should be taken in time to control the amount of groundwater exploitation, new irrigation methods and rational fertilization should be adopted to reduce the continuous decline of local groundwater level and water quality deterioration.