Estuary is a transition zone between land and sea as well as freshwater and salt water. In
the estuary, the water carrying agricultural, industrial and domestic wastes are deposited as
sediment. Distribution of organic carbon, total phosphorus and total nitrogen in the
sediments of Manakudy estuary has been studied. Based on their nature, five stations have
been earmarked for sampling. The C/N ratio of these sediments is very high compared to the
sediments from Mandovi estuary goa.