SALINITY CONTROL ON THE DISTRIBUTION OF SALT-MARSH FORAMINIFERA (GREAT-MARSHES, MASSACHUSETTS)

Foraminiferal faunas along 12 transects through high and upper marsh vary with salinity and show no relationship with elevation above mean sea level. Salinity is diluted by precipitation and seepage of ground water and is therefore independent of elevation. Based on salinity values and hydrological situation, the marsh habitat is divided into three salinity-based units, each characterized by a different foraminiferal assemblage. An important low salinity indicator is Haplophragmoides manilaensis. In the Great Marshes, foraminifera can be used in paleoecological studies but not as indicators of minor sea level changes.