Spatial and Temporal Variation of Microbial Community Structure In Surficial Sediments of Cochin Estuary

This thesis entitled spatial and temporal variarion of microbial community structure in surficial sediments of cochin estuary.In the estuarine and coastal systems, organic matter (OM) is derived not only from autochthonous primary production, but also from allochthonous (terrestrial) organic matter (OM) delivered by river discharge and runoff. A significant portion of the OM sinks through the water column and is ultimately stored in carbon pool in the sediments.Analysis of spatial and temporal variation in benthic microbial community of a tropical estuary was conducted for the first time using non selective measures that affirms that PLFA approach is a sensitive and reliable method in determining microbial community structures of surficial sediments of estuary.The close relationship between the concentrations of the microbial fatty acids and total biomass indicates that bacteria could account for the largest proportion of the biomass in the sediments.This is first study that has documented the changes in microbial community composition linkage to biotic and abiotic variables in benthic estuarine ecosystem. This contemporaneous community will be the backdrop for understanding the response of autochthonous community to increasing anthropogenic stress.

Department of Marine Microbiology,National Institute of Oceanography

Cochin University of Science and Technology