Identifying Groundwater Recharge Sources and Mechanisms using Hydrochemistry and Environmental Stable Isotopes in High Arsenic Holocene Aquifers of Bangladesh

• DOI: 10.12982/cmjs.2024.067
• Publication Date: 2024-09-23T03:17:07Z
• Authors: Md. Enamul Huq; David Lopez-Carr; ; Fahad Almutlaq; ; Xijun Wu; ; Jiang Wu
• Keywords: Environmental isotopes

Und erstanding the sources and mechanisms of aquifer recharge is critical for water resource management. So far, this first comprehensive study to explore groundwater applying stable environmental isotopes hydrogeochemical properties in Southwestern Bangladesh. Water samples from different (groundwater, surface (pond), river rain water) high arsenic (As) Holocene aquifers were used investigate chemical tracers (δ18O δ2H) hydrogeological features, sources, processes. The analytical results showed As concentration observed 590.7 μg/L. High was identified by a low pH value, medium HCO3- TDS with NO3- SO42-. However, depleted δ2H δ18O signatures indicated that local vertical rainfall key source area. process pond seepage irrigation return flow also contribute recharge. Isotopic suggested connectivity amongst significant reduced heavier isotope reveals extra recharging floods mountains altitude. Due heterogeneous anisotropic structure system spatial variability shows limited lateral connectivity. combined analyses Cl- ion evaporation primary cause discharge. Based on processes groundwater, present provides crucial baseline knowledge establishing sustainable management strategy. findings can guide development targeted strategies improvement understanding