INCIDENCE OF HEAVY-METALS IN THE MANGROVE FLORA AND SEDIMENTS IN KERALA, INDIA

The mangroves of Kerala on the south-west coast of India are fast disa ppearing due to land reclamation and other anthropogenic disturbances. There are very few ecosystem level studies made in these much threate ned biotopes in Kerala. The present study involves the measurement of heavy metals in the mangrove flora and sediments of three mangrove hab itats along the Kerala coast. Sampling was carried out for a period of one year at bi-monthly intervals, with concentrations of Fe, Mn, Cu, Zn, Pb and Co analysed using atomic absorption spectrophotometry. An a ppreciable variation was observed in metal concentrations in different mangrove species. Cu, Zn and Pb were found to be in higher concentrat ions in Avicennia officinalis whereas higher levels of Fe, Mn and Co w ere observed in the species Barringtonia racemosa. The analysis of hea vy metals indicated a high level of metal pollutants such as Fe, Cu, Z n and Pb in the mangrove habitats of Quilon and Veli compared to the r elatively uncontaminated areas of Kumarakom.