The study of the ostracod fauna of shallow marine environments strongly influenced by human activity off the Mae Khlong river mouth (NW Gulf of Thailand, north of1-1/2eiehaburd allows the identification of34 species, belonging to thanatocoenosis and, subordinately, to biocoenosis. The relationships between ostracods and water depth and substrate are discussed in order to identifif species which are tolerant of the changes in these environmental parameters. °strewed distributions are also related to salinity pH and dissolved oxygen. Moreover; using the Shannon Weaver index as a measure of ecosystem health, it has been possible to highlight the deterioration of environmental conditions at the investigated sampling stations and to identify the species which are tolerant of human-induced environmental changes.
