Fundamentals of Microbiology

4.2.3 Estuarine microbiota

An estuary is an interface between fresh and marine habitats. This results in a body of water that is brackish in nature. There are some organisms that have specifically adapted to these conditions, but most organisms in estuaries are from either fresh or salt water origins. The rapid variations in physical and chemical properties in estuaries lead to the establishment of unique microbial communities. The wide range of salt concentration and pH allow diversity of microorganisms. The biomass in estuaries is high due to high nutrient levels. The sediment conditions fluctuate less than the water; sediment bacteria are less subject to the rapid changes in salinity and temperature and so are more similar to normal ocean or freshwater sediment bacteria.