深层承压含水层人工回灌条件下地下水中硝酸根的衰减

Attenuation of nitrate in a deep confined aquifer during artificial recharge process

收集了某地深层承压含水层人工回灌从2012年8月13日至2013年1月16日的水质数据,研究了回灌过程中地下水中NO-3的衰减。在深层承压含水层中,硝酸根的衰减主要受反硝化作用的影响。讨论了p H值、电子供体、温度、溶解氧等影响因素,结果表明,在本次回灌过程中,p H值、电子供体对NO-3的衰减基本没有影响,硝酸根衰减主要受到地下水水温及溶解氧的影响。回灌过程中,由于地下水水温逐渐下降,溶解氧质量浓度逐渐上升,NO-3衰减半衰期经历了一个先保持稳定而后迅速上升的过程。

In recent years, excessive exploitation of groundwater has caused many environmental, geological and ecological problems, so artificial recharge has been adopted in many places. However, whether artificial groundwater recharge will lead to negative effects on groundwater environment needs further research. In this study, water quality data was collected from August 13, 2012 when the recharge began, to January 16, 2013 to study attenuation of nitrate in a deep confined aquifer during artificial recharge process. In this deep confined aquifer, the attenuation of nitrate was dominated by denitrification. The p H, electron donor, temperature, and dissolved oxygen（DO） which can affect denitrification were studied. The results showed that the p H and electron donor had basically no influence on nitrate attenuation, which was mainly influenced by water temperature and DO in this study. During the recharge process, because of decrease of water temperature and increase of DO, the half-life of nitrate increased rapidly after a stable period.