ABSTRACT
Simultaneous study of intertidal foraminifera and estuarine environment in the world’s largest mangrove forest Sundarbans was carried out in order to identify changes in shell composition of foraminifera, loss of faunal species and diversity, morphological abnormity enhancement and possibility of ecological imbalance. As coastal deltas are dynamic low-lying areas, environmental changes are so much crucial here due to relative sea level rise with increased salt water intrusion and delta tilting as well as anthropogenic activities. In this rigorous study, a total of 32 samples were collected from surficial sediment of supratidal, intertidal and dune environment along the western coast of Bangladesh. As an abundant diverse group and efficient bio-monitoring tool, total 17 species representing 9 families of benthic foraminifera were recorded for assessing the ecological condition of that area. In this study, diversity index (H) and foraminiferal abnormality index show the indication of environmental stress specially in several must going tourist spots like Dimer char, Kochikhali, Jamtola, Katka, and Dublar Char. The frequency distribution and hierarchical cluster analysis highlighted similarities of homogenous microforams in different locations and foraminiferal diversity loss along the coast.
