I think it will be helpful for everyone who wants to know about scope and type of ecology, general concepts of ecology, the open ocean, coastal water, floor of the sea, estuaries, coral reef, beaches, islands, salt marshes, and dunes & shingle, major ecological divisions of marine habitat, global warming effect on marine fauna and coral islands, comparative study of freshwater fauna, brackish water and marine ecosystems, fauna characteristics of sandy, muddy and rocky shores. Factors affecting adaptation and distribution of marine organisms, up-welling and productivity of estuarine ecosystem,Food chain, food webs and ecological niche in marine environment, energetic of a marine ecosystem, ecology of the Bay of Bengal and its major estuaries, ecological model of abiotic and biotic components, relationships between marine fishes with other abiotic and biotic factors,factors which causing lose of Biodiversity, Estuarine ecology: Definition, formation and components of estuarine environment. Classification of estuary on the basis of salinity ranges, speciation and colonization in estuaries.