Role of intrinsic physicochemical parameters on multi-element distribution in surface sediment of the Devi River estuary, eastern India

Shaheen Akhtar; Sk Md Equeenuddin; Priyadarsi D Roy

doi:10.1016/j.chemosphere.2022.134195

Role of intrinsic physicochemical parameters on multi-element distribution in surface sediment of the Devi River estuary, eastern India

Chemosphere. 2022 Jun:297:134195. doi: 10.1016/j.chemosphere.2022.134195. Epub 2022 Mar 3.

Authors

Shaheen Akhtar¹, Sk Md Equeenuddin², Priyadarsi D Roy³

Affiliations

¹ Department of Earth and Atmospheric Sciences, National Institute of Technology, Rourkela, 769008, Odisha, India.
² Department of Earth and Atmospheric Sciences, National Institute of Technology, Rourkela, 769008, Odisha, India. Electronic address: md_equeen@yahoo.co.in.
³ Instituto de Geología, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, CP 04510, CDMX, Mexico.

PMID: 35248595
DOI: 10.1016/j.chemosphere.2022.134195

Abstract

Multi-element composition including rare earth elements (REE) of surface sediment from the Devi river estuary, eastern coast of India, have been analysed in order to study the weathering characteristics and provenance of sediment along with their behaviour under different physicochemical conditions. These sediments with dominantly felsic provenance have undergone low to moderate chemical alterations. Bulk chemical composition is mainly represented by SiO₂, Al₂O₃, Fe₂O₃ and K₂O. Concentrations of Ba, Nb, Pb, Rb, Th and Zr are above their respective upper crustal abundances. High LREE/HREE ratio, negative Eu anomalies, and (La/Yb)_n and (Tb/Yb)_n values confirm that sediments are dominantly derived from the Eastern Ghat Group of rocks. Upper estuary sediments show negative Eu anomalies which is similar to that of the source. However, positive Eu anomaly is mostly observed in lower estuary. Contrasting Eu anomalies between upper- and lower-estuarine sediments are uncharacteristic of previously studied major global estuaries. Strong negative correlation between Mn and Eu suggests control of redox conditions over distribution of Eu. Concentration of REEs, Sc, Fe, Mo, V, Zn, Zr, Nb, U, Ti, Na and P increases up to 20 ppt salinity, and followed by declining trend towards mouth. This is mostly due to removal through flocculation of colloidal particles from water column during fresh- and saline-water interaction. This could be the first report about coagulation-based behaviour of Mo in estuarine environment. There is gradual decline in concentration of Cr, Co, Ni, Cu, Rb, Sr, Sb, Cs, Ba, Pb, Al, Mn, Mg, Ca and K with increase in salinity which is attributed to saline induced desorption of elements from sediments. The SiO₂ content shows increasing trend towards mouth. Findings of this study highlight the importance of intrinsic physicochemical parameters, mainly salinity and redox condition, on governing geochemical behaviour of different elements including REE in mangrove dominated estuarine sediment.

Keywords: Devi estuary sediment; Rare earth element; Redox condition; Salinity gradient; Source.

MeSH terms

Environmental Monitoring
Estuaries
Geologic Sediments / chemistry
India
Lead / analysis
Metals, Rare Earth* / analysis
Rivers / chemistry
Silicon Dioxide / analysis
Water / analysis
Water Pollutants, Chemical* / analysis

Substances

Metals, Rare Earth
Water Pollutants, Chemical
Water
Lead
Silicon Dioxide