Geochemical assessment of heavy metals, sediment pollution, and lake-formation processes in al Wathba hypersaline Sabkha, United Arab Emirates

Document Type

Article

Source of Publication

Total Environment Advances

Publication Date

12-1-2025

Abstract

Hypersaline lakes are dynamic yet fragile ecosystems that not only preserve ecological, geochemical, and climatic processes but also serve as critical indicators of environmental change. Understanding their vulnerability to pollution is essential for assessing ecosystem health and guiding management strategies. This study investigates the geochemical dynamics of Al Wathba Salt Lake (AWSL), a man-made hypersaline lake in Abu Dhabi, United Arab Emirates, with emphasis on its water and sediment pollution status and formation processes. Multivariate statistical tools, including enrichment factors (EF), geo-accumulation indices (Igeo), and principal component analysis (PCA), were applied to trace contamination sources and evaluate environmental risks. Results revealed anomalous geochemical conditions, including unusually low pH values (2.14–5.14), extreme salinity (up to 189.2 ppt), and exceptionally high enrichment of Cl, S, Cd, Hg, and Cr in sediments. Elevated total organic carbon (TOC) at 25.5% and sodium depletion indicate euxinic conditions and active sulphate precipitation. PCA showed that contamination arises from both natural factors (substratum weathering, groundwater inflow, atmospheric deposition) and anthropogenic inputs (treated wastewater, tourism). These findings provide the first comprehensive demonstration of AWSL's deviation from typical hypersaline systems, usually neutral to alkaline and dominated by sodium-chloride chemistry, and its high susceptibility to heavy metal contamination. The study underscores the urgent need for targeted monitoring, pollution mitigation, and sustainable management of hypersaline ecosystems in arid environments.

ISSN

2950-3957

Publisher

Elsevier BV

Volume

16

Disciplines

Life Sciences

Keywords

Geochemical analysis, Heavy metal contamination, Hypersaline, Principal component analysis (PCA), Total dissolved solids (TDS), Total organic carbon (TOC)

Scopus ID

105022645857

Indexed in Scopus

yes

Open Access

no

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