Prevalence of pollution indicators in Palk bay coastal zone, Southern India

Abstract

In this study, the sea water and sediment samples of four different locations were collected from Palk bay regions during 2014 for pollution indicators study. All the bacterial parameters were higher during the rainy season compared to summer season in all the sampling locations of the Palk bay regions. In the water samples, among the pollution indicator bacterial groups, TC and TS counts were highest 0.67 10.3 [×103] ml−1 and 0.8 10.8 [×102] ml−1 during monsoon, and the least 0.54 8.5 [×103] ml−1 and 0.7 9.0 [×102] ml−1 were noticed during summer. In monsoon sediment sample, the higher VC count was observed in Thondi (2100 g−1) followed by Mimisal (1700 g−1), Manamelkudi (960 g−1) and Devipattinam (200 g−1). The pollution index (PI) of each location was calculated and was showed a remarkable microbial contamination was observed in sediment sample than water sample. The order of PI observed were Thondi > Mimisal > Manamelkudi > Devipattinam. The highest PI ratio (15.5) was observed in Devipattinam sediment sample at monsoon season while lowest (2.5) was noticed in Devipattinam water sample at summer season. The results indicated that the coastal environment is highly exposed to human excreta that suggesting to avoid direct contact. Hence, throughout impoundment is needed to protect coastal environments.