Geochemical fractionation of heavy metals in Chilka Lake (east coast of India) - a tropical coastal lagoon

Journal Article · Fri Dec 01 04:00:00 EST 1995 · Environmental Geology and Water Sciences

DOI:https://doi.org/10.1007/BF00770470· OSTI ID:482504

Panda, D; Subramanian, V ^[1]; Panigrahy, R C ^[2]

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1. Jawaharial Nehru Univ., New Delhi (India)
2. Berhampur Univ. (India)

Chilka lake, the largest coastal lagoon of Asia is one of the most dynamic ecosystems along the Indian coast. Historically the lagoon has undergone a considerable reduction in surface area due, in part, to input from natural processes but mostly due to human activities. The purpose of this investigation is to document the heavy metals` affinity for specific geochemical phases in the recently deposited sediments in the lagoon. Thirty-three samples were collected and analyzed for different geochemical phases of Fe, Mn, Cu, Cr, Ni, Pb, and Zn utilizing a sequential extraction scheme. In the nonlithogenous fraction, the exchangeable fraction was not geochemically significant, having <2% of the total metal concentration for all the elements. However, the carbonate fraction contained the following percentages of the total concentration: <1% Fe, 13% Mn, 6% Cu, 4% Cr, 8% Ni, 13% Pb, and 12% Zn, suggesting the detrital origin of the sediments. Reducible and organic matter-bound fractions were the significant phases in the nonlithogenous fraction, containing 9% Fe, 16% Mn, 15% Cu, 16% Cr, 16% Ni, 14% Pb, and 14% Zn in the former and 4% Fe, 3% Mn, 17% Cu, 3% Cr, 14% Ni, 15% Pb, and 14% Zn in the latter. The phenomenon has been attributed to the scavenging affinity of Fe-Mn oxides and affinity for sorption into organic matter of the lagoon sediments. The lithogenous, residual fraction generally considered as a guide for natural background values was determined to contain 87% Fe, 67% Mn, 61% Cu, 77% Cr, 61.3% Ni, 56% Pb, and 60% Zn of the total concentrations. 58 refs., 7 figs., 5 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 482504
• Journal Information: Environmental Geology and Water Sciences, Journal Name: Environmental Geology and Water Sciences Journal Issue: 4 Vol. 26; ISSN EGWSEI; ISSN 0177-5146
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
COASTAL REGIONS
CONTAMINATION
FRACTIONATION
GEOCHEMISTRY
INDIA
LAKES
METALS
TROPICAL REGIONS