Spatial variability of heavy metals in estuarine, mangrove and coastal ecosystems along Parangipettai, Southeast coast of India

• Published in: Environmental pollution (1987) 2016-11, Vol.218, p.186-195
• Main Authors: Sundaramanickam, Arumugam, Shanmugam, Nadanasabesan, Cholan, Shanmugam, Kumaresan, Saravanan, Madeswaran, Perumal, Balasubramanian, Thangavel
• Format: Article
• Language: English
• Subjects: Aquatic pollution; Ecosystem; Environmental Monitoring; Environmental Pollution - analysis; Estuaries; Geologic Sediments - chemistry; Heavy metal; India; Mangrove environment; Metals, Heavy - analysis; Power Plants; Seasons; Sediment quality; Soil Pollutants - analysis; Water Pollutants, Chemical - analysis; Wetlands
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2016.07.048

An elaborate survey on the contamination of heavy metals was carried out in surface sediments of different ecosystems such as Vellar-Coleroon estuarine, Pichavaram mangrove and coastal region of Parangipettai, Southeast coast of India. The study was intended since, the coal based thermal power plant and oil refinery plant are proposed to set up along this coast and aquaculture industries and dredging activities are developing. The parameters such as soil texture, pH, total organic carbon (TOC) and heavy metal (Fe, Mn, Cu, Cd, Zn and Ni) concentrations were analyzed for the surface sediments during pre and postmonsoon seasons. Among the metals analyzed, Fe and Mn were found to have dominant as the levels were recorded as 11,804 μg g−1 and 845.2 μg g−1 respectively. A significant correlation was observed between total organic carbon (TOC) and heavy metals. In the mangrove ecosystem, the levels of heavy metals found to be maximum indicating that the rich organic matter acts as an efficient binding agent for metals. The overall finding of the present study indicated that the sediments from the entire Vellar-Coleroon estuarine and Pichavaram mangrove ecosystems were found moderately polluted with cadmium metal. The result of cluster analysis indicated disparity in accumulation of heavy metals in sediments of different ecosystems due to the variations in organic matter. The heavy metals were transported from land to coastal through flood during monsoon season reflecting the variations in their levels in different ecosystems at postmonsoon season. •A significant variation in the heavy metal levels was observed i.e. the higher level in postmonsoon as compare to premonsoon season.•The soil texture and TOC play a crucial role in retaining the metals in sediments.•Mangrove sediments with high silt and clay were found efficient in binding the metals.•The overall finding of the present study indicated that the Cd was found with moderately polluted.