such changes were discussed based on single estuary studies (Chen and Twilley, 1999) and comparing different biogeographical regions (Duke et al., 1998). The present study showed that there were similar patterns of change in mangrove species composition along the estuarine salinity gradient. It was observed that R. mangle and A. germinans preferentially occur, respectively, at lower and upper estuarine zones. At Paraguaçu estuary, there was a very clear species