Abstract
Tropical mangroves are most productive and highly sensitive to environmental change and act as good bio-indicators of the environmental quality and health of any coastal ecosystem. The present study initiated to know the current ecological status of mangrove species at four selected study sites namely Bhavnagar (Ghogha coast), Bharuch (Dahej coast), Surat (Dumas beach) and Navsari (Purna estuaries), Gulf of Khambhat, Gujarat, India. Observation for a period of one year from January 2014 to December 2014. Mangroves were evaluated for their community structures at each site by standard quadrant method and different diversity indices were used for characterize the species diversity in a mangrove community. The mangrove forest habitat supports the occurrence of a total 16 species (6 mangrove species and 10 associated plant species), 15 species occurred at Navsari, whereas 7, 6 and 10 species occurred at Bhavnagar, Bharuch and Surat respectively. Out of six mangrove species, Avicennia marina was found to be most dominant and abundant mangroves occurring among all the four study locations. The most abundant and dominant mangrove associates were Suaeda maritima and Sesuvium portulacastrum. Simpson's diversity index was varied at a range of zero to 0.6538, showing the presence of less mangrove diversity. Navsari site presented higher diversity with Shannon and Wiener Species Diversity Index of 1.179 in comparison to other sites. The present study revealed that the species abundance, density and diversity of flora associates depend upon species density and diversity of mangroves. Therefore, mangrove forest habitats need to be protected and regular assess.