School of Civil Engineering, Sun Yat-sen University, Guangzhou 510275, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China.
State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, China.
Mar Pollut Bull. 2022 Nov;184:114231. doi: 10.1016/j.marpolbul.2022.114231. Epub 2022 Oct 18.
Coastal aquifers are vulnerable to seawater intrusion and salinization due to groundwater pumping. Most research on salinization vulnerability and pumping rate optimization considers constant seaside boundary. However, tidal fluctuations may propagate through aquifers and affect pumping-induced seawater intrusion. We numerically tested the combined effects of tidal fluctuations and groundwater pumping on the variable-density groundwater flow and salt transport in aquifers with pumping wells close to the coast. The simulations showed that tidal fluctuations relieved seawater intrusion due to groundwater extraction. Stronger tidal fluctuation created larger upper saline plume which inhibited the seawater intrusion in the lower aquifer. Compared with those without tides, the tidal fluctuations with a tidal amplitude of 1 m could increase maximum pumping rate by 35.2 % and 28.7 % in flux- and head-controlled systems, respectively. These results suggest that combined impacts of tides and pumping should be considered in assessing seawater intrusion and designing more sophisticated pumping optimization.
沿海含水层由于地下水抽取而容易受到海水入侵和盐化的影响。大多数关于盐化脆弱性和抽水泵优化的研究都考虑了固定的海滨边界。然而，潮汐波动可能会在含水层中传播，并影响抽水泵引起的海水入侵。我们通过数值模拟测试了潮汐波动和地下水抽取对靠近海岸的抽水井的含水层中变密度地下水流动和盐运移的综合影响。模拟结果表明，由于地下水抽取，潮汐波动缓解了海水入侵。更强的潮汐波动会产生更大的上盐水羽流，从而抑制了下层含水层中的海水入侵。与没有潮汐的情况相比，潮汐幅度为 1 米的潮汐波动可以使流量控制和水头控制系统中的最大抽水泵分别增加 35.2%和 28.7%。这些结果表明，在评估海水入侵和设计更复杂的抽水泵优化时，应考虑潮汐和抽水泵的综合影响。
