Ecology, Environment and Conservation Paper

MINOR AND TRACE ELEMENTS IN TAMBRAPARNI ESTUARY, INDIA

D. Vetha Roy and N. Chandrasekar

Abstract

River Tambraparni forms an estuary at Punnakayal along the Bay of Bengal. Surface sediment samples analysed by standard methods, have indicated high organic pollution levels especially around Zone 1 with fine sediments (Clay: 21.6% and 18.36%) both during the premonsoon as well as post-monsoon seasons (Organic carbon 1.28% and I .54%).The minor and trace elements have also recorded higher values in this region where an industrial complex is situated (Mn: 720 and 519 ppm, Hg: 52.75 and 48.28 ppm, Cd: 13.6 and 1.5 ppm, Zn: 218.4 and 2.22 ppm, Pb: 30.3 and 27 ppm). The Geo accumulation indices of certain trace metals are found at alarmingly high levels (Hg: Zn: Cd = 9.24, 0.45 and 4.54 pre-monsoon). However, sequential extraction studies have indicated that most of the trace elements remain only as sedimentary and not released to the water column.