Spatial assessment of submarine groundwater discharge influence on aquifer water quality in the coastal region of Chettikulam to Kolachel, southern India: using SMI and HFE-D techniques.
R Sakthi Priya, A Antony Ravindran, S Richard Abishek
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引用次数: 0
Abstract
Submarine Groundwater Discharge (SGD) has a global impact, affecting coastal aquifers, the freshwater environment, and contributing to coastal development. The present study investigates the impact of Submarine Groundwater Discharge (SGD) on groundwater geochemistry along the coast from Chettikulam to Kolachel in Southern India, with an emphasis on regional changes pre and post monsoons in the years 2023-2024. A total of 80 groundwater samples (40 from both monsoons) were analyzed using hydrochemical plots such as Piper, Wilcox, Gibbs, and Hydrochemical Facies Evolution Diagrams (HFE-D), along with AquaChem software and spatial mapping techniques. Hydrogeochemical analysis reveals significant seawater intrusion during the pre-monsoon period, with 48% of groundwater samples categorized under the Mixed Ca-Mg-Cl facies and 30% under the Ca-Cl facies, leading to elevated salinity, total dissolved solids (TDS), chloride, and sulfate concentrations. In contrast, post-monsoon conditions demonstrate improved water quality due to monsoonal recharge, with 55% of samples in the mixed Ca-Mg-Cl facies but exhibiting reduced salinity. Water Quality Index (WQI) analysis shows an increase in 'Excellent' water samples from 22.5% pre-monsoon to 37.5% post-monsoon. The Wilcox diagram highlights a reduction in salinity hazards, improving groundwater suitability for irrigation. The Seawater Mixing Index (SMI) indicates the seawater intrusion in coastal zones, although monsoonal dilution mitigates its effects. Seasonal variation in hydrochemical facies reveals a decrease in the freshening phase from 60% pre-monsoon to 45% post-monsoon, alongside an expansion of the intrusion phase from 40 to 55%. The study underscores the need for ongoing groundwater monitoring and effective water management strategies to sustainable coastal aquifers impacted by Submarine Groundwater Discharge (SGD).
期刊介绍:
Environmental Geochemistry and Health publishes original research papers and review papers across the broad field of environmental geochemistry. Environmental geochemistry and health establishes and explains links between the natural or disturbed chemical composition of the earth’s surface and the health of plants, animals and people.
Beneficial elements regulate or promote enzymatic and hormonal activity whereas other elements may be toxic. Bedrock geochemistry controls the composition of soil and hence that of water and vegetation. Environmental issues, such as pollution, arising from the extraction and use of mineral resources, are discussed. The effects of contaminants introduced into the earth’s geochemical systems are examined. Geochemical surveys of soil, water and plants show how major and trace elements are distributed geographically. Associated epidemiological studies reveal the possibility of causal links between the natural or disturbed geochemical environment and disease. Experimental research illuminates the nature or consequences of natural or disturbed geochemical processes.
The journal particularly welcomes novel research linking environmental geochemistry and health issues on such topics as: heavy metals (including mercury), persistent organic pollutants (POPs), and mixed chemicals emitted through human activities, such as uncontrolled recycling of electronic-waste; waste recycling; surface-atmospheric interaction processes (natural and anthropogenic emissions, vertical transport, deposition, and physical-chemical interaction) of gases and aerosols; phytoremediation/restoration of contaminated sites; food contamination and safety; environmental effects of medicines; effects and toxicity of mixed pollutants; speciation of heavy metals/metalloids; effects of mining; disturbed geochemistry from human behavior, natural or man-made hazards; particle and nanoparticle toxicology; risk and the vulnerability of populations, etc.