Study on the Processes Influencing and Importance of Ecological Water Replenishment for Groundwater Resources: A Case Study in Yongding River

Abstract

There has been notable depletion of groundwater resources globally in recent decades. Groundwater can be conserved by ecological water replenishment. An understanding of the factors influencing the effect of ecological water replenishment on groundwater recharge is of great significance for water resource management. This study used the improved water table fluctuation and water equilibrium method and Spearman correlation analysis in R to evaluate the effect of ecological water replenishment on groundwater recharge. Furthermore, the correlations between groundwater recharge and topography, hydrogeological conditions, and meteorological factors were analyzed. Groundwater storage in the plain area of the Yongding River (Beijing section) increased by 2.17 × 108 m3 in 2020, equating to an increase in the regional groundwater level of 73.6% (increase of 0.1–9.1 m, arithmetic mean of 2.3 m). The main sources of groundwater recharge are ecological water replenishment and precipitation. The ecological water replenishment first recharged the Ordovician limestone aquifer in the gorge area, following which karst water overflowed through the fault zone to resupply the Quaternary groundwater in the plain area, resulting in a lag in the groundwater recharge effect. Groundwater recharge was positively correlated with ground elevation and aquifer permeability and negatively correlated with the thickness of Quaternary strata and the distance between the recharge point and Yongdinghe fault zone. This study can help to better explain the effect and impact of ecological water replenishment on groundwater resource recharge and its implications for improving ecological water replenishment projects.

A numerical assessment on the managed aquifer recharge to achieve sustainable groundwater development in Chaobai River area, Beijing, China

“…Pilot MAR project has been implemented since 2015 (Cao et al, 2022;Zhou et al, 2021). Modelling studies have also been carried out to evaluate the performance of the current MAR implementation and the potential of the future MAR operation in Beijing (Hao et al, 2014;Hu et al, 2019;Ma et al, 2020;Nan et al, 2016;Xu et al, 2022;Zhou et al, 2012). However, most of these modelling studies were only dedicated to the local-scale simulation of MAR sites with relatively short simulation period, which lack the capability to evaluate the contribution of the MAR operation to restoring the groundwater depletion of the entire plain region and support the decision making for an integrated groundwater management of the city.…”