Seasonal variability in trace metal concentrations in sediment samples from the Puducherry and Cuddalore coasts of Tamil Nadu, India

Abstract

The Puducherry-Cuddalore coastal region was chosen for research because these two cities receive the majority of their anthropogenic inputs from the Ponnaiyar and Gadilam rivers, which supply domestic, industrial, fishing port, and agricultural inputs. In southern Tamil Nadu, the Ponnaiyar and Gadilam rivers, as well as other minor rivers, combine and discharge into the southeastern Indian Ocean. Some studies have been carried out to investigate the impact of anthropogenic, industrial, and other influences on surface sediment samples along Tamil Nadu's south-east coast, from Puducherry to Cuddalore. A detailed assessment of these findings is explained in this research. Geochemistry and geology, as well as alterations in sediments, have all been widely researched. Heavy metals were absorbed by alluvial sands, silts, clays, and organic matter, which is also an indication of pollution in the environment. As a result, the metal content in pre-monsoon sediments is lower in Puducherry coastal areas than in Cuddalore coastal areas. Because of a rise in clay composition, higher trace metals were detected in post-monsoon sediments than in pre-monsoon sediments. Contamination levels in Puducherry and Cuddalore coastal areas were moderate to high in post-monsoon than pre-monsoon periods, with the exception of Cr, which significantly above the range of widespread pollution in post-monsoon periods. Sediments sampled from Puducherry and Cuddalore offshore were found to have moderate to considerable contamination. With the notable exception of lead, most elements of trace metal levels in sediments indicate relatively low levels of pollution. Among the consequences discussed in the report's findings are alterations in post-monsoon hydrodynamic processes and environmental health of the marine ecosystem.