Geochemical and geo-statistical assessment of heavy metal concentration in the sediments of different coastal ecosystems of Andaman Islands, India

• Published in: Estuarine, coastal and shelf science Vol. 87; no. 2; pp. 253 - 264
• Main Authors: Nobi, E.P., Dilipan, E., Thangaradjou, T., Sivakumar, K., Kannan, L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 10.04.2010; Elsevier
• Subjects: Andaman Island; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Brackish; Brackish water ecosystems; Cadmium; Chromium; Coastal; Ecosystems; Fundamental and applied biological sciences. Psychology; General aspects; Heavy metals; India; Lead (metal); mangroves; Marine; Nickel; seagrasses; sediment pollution; Sediments; Synecology; Asia; India; mangroves; seagrasses; Andaman Island; heavy metals; sediment pollution; India; Brackish water environment; Geochemistry; Andaman Islands; Sediments; Heavy metal; Concentration measurement; Pollution; Mangrove; Ecosystem; Sea grass
• ISSN: 0272-7714; 1096-0015
• DOI: 10.1016/j.ecss.2009.12.019

Spatial distribution of metal concentrations in the surface sediment samples collected from 16 marine locations covering different coastal ecosystems such as mangroves, seagrasses, dead coral and sandy beaches of the Andaman islands, India was studied. pH, EC, sediment grain size and heavy metal (Al, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn) concentrations were determined and contamination factor (CF) and geo-accumulation index (I geo) were calculated to understand the pollution status of the study area based on the background values. CF of different heavy metals has revealed that different metals have different levels of accumulation viz. Al: 0.01–0.22, Mg: 0.38–1.85, Fe: 0.06–0.74, Mn: 0.04–1.18, Cu: 0.18–2.93, Cr: 0.52–12.6, Zn: 0.3–1.39, Ni: 0.06–0.89, Pb: BDL–0.74, Co: 0.1–0.35 and Cd: 2.3–12.9. In general the metal concentration was less in these ecosystems when compared to similar ecosystems of mainland of India. Concentration of some metals like Cr and Cd was comparatively higher than the background values which is an important issue of concern to the coastal managers of the region. Spatial data on heavy metals, collected now, would help the coastal zone managers to identify the vulnerable sites and take remedial actions.