Land use alters the alignment of Arsenic and Chromium co-contamination in the unconsolidated aquifer under reducing environments of the Mid-Gangetic Plains Academic Article in Scopus uri icon

abstract

  • The Indo-Gangetic Plain, well known for its alluvial landscape and dense human settlement, is facing rapid industrialization and urbanization, leading to high stress on its aquifers. Arsenic and chromium co-occurrence in shallow aquifers is a growing global concern, influenced by redox conditions, geochemistry, and human activities. We aim to address the influence of the suburban and urban land use on the co-contamination of As and Cr, using various geostatistical tools, models, and indices. Among twenty-six (n = 26) groundwater samples, the majority of water types were found to be Mg2+-HCO3¿ and Na+-K+ exhibiting carbonate weathering and evaporation enrichments, with saturation indices exhibiting the supersaturation of calcite and dolomite. Probability exceedance implied inverse correlation between contaminant concentrations and the probability of their likelihood of regulatory thresholds. Factor analysis indicates that the natural alignment of contaminants, particularly As and Cr, is maintained under suburban land use but significantly altered in urban settings. No specific trend of As was observed in suburban areas, but in urban settings, it showed a positive correlation with Total organic carbon (TOC) and Sulphate (SO¿2¿), indicating anthropogenic influences like subsurface leaching and also justify the results of factor analysis. An integrated cluster heatmap has identified a trifecta of As, Cr, and lead (Pb), closely linked to pH, DO, and K+, highlighting the effects of increased anthropogenic activities in alluvial floodplains. Finally, a conceptual model was developed to clarify the common processes in these environments, facilitating the creation of universal management strategies for aquifers impacted by As and Cr co-contamination. © 2025 Elsevier B.V.

publication date

  • August 10, 2025