Summary of Abstract Submission

Abstract Submission No. IO50-09-0027PresentationPoster

VARIATIONS IN HETEROTROPHIC, INDICATOR AND PATHOGENIC BACTERIA IN THE COASTAL BAY OF BENGAL: INFLUENCE OF PHYSICAL PROCESSES

Sudharani, P*1, Srinivas, T. N. R1, Sarma, V. V. S. S.1

1 CSIR-Nataional Institute of Oceanography, RC, Visakhapatnam, India

ABSTRACT :

The influence of physical processes on the variations in heterotrophic (HBC), indicator and pathogenic bacteria were examined in the coastal Bay of Bengal. The study region can be divided into three periods based on physical processes: cool and high saline period (February to April), warmer period (May to August) and low saline period (September to December). HBC were higher and observed throughout the water column in the cool and high saline period in the coastal region due to high nutrients resulted from upwelling whereas they were concentrated in the surface during warmer period. Total coliforms (TCC)/Escherichia coli were observed during low saline and warmer periods when East India Coastal Currents bring riverine water from the north with higher concentration of ammonium indicating land runoff. Aeromonas hydrophila, Enterococcus faecalis, Salmonella, E. coli O157:H7 were noticed only during warmer period in the coastal region. On the other hand, higher HBC were noticed during both cold and warmer periods in the offshore than coastal region probably due to the less inhibitory activities, such as grazing by protozoans, heavy metals, antibiotics etc. Aeromonas hydrophila, TCC, E. coli, E.coli O157:H7 and Eneterococcus faecalis counts were abundant during warmer and low saline periods in the offshore. Salmonella and Klebsiella pneumonia were observed only during low saline period suggesting land-runoff is a major source. This study revealed that physical processes have significant impacts on the abundance of heterotrophic, indicator and pathogenic bacteria in the coastal Bay of Bengal and the