Habitat-Based Diversity Assessment of Mangroves of Thane Creek, West Coast, India

Abstract

A habitat-based plant diversity assessment was carried out in order to appraise the current status of the mangroves of Thane creek (Maharashtra, India) for appropriate measures for conservation of the fragile ecosystem. ‘Partially protected’ and ‘disturbed’ are the two major categories of habitat recognized during the study. In addition, mangrove vegetation of each habitat is quantitatively analyzed for its diversity (species richness and distribution) and growth parameters (above ground biomass). Habitat is found to be responsible for the physicochemical setup of mangrove swamps, which decides a community pattern in mangroves. Out of the 18 species recorded from the Maharashtra coast, Thane creek exhibits eight mangroves, viz., Avicennia marina Vahl., Avicennia officinalis L., Bruguiera cylindrica Bl., Sonneratia apetala Buch.-Ham., Ceriops tagal Robin, Excoecaria agallocha L., Acanthus ilicifolius L. and Aegiceras corniculatum Blanco. No zonation pattern could be recognized within the present day mangrove forest. In general, the vegetation is dominated by Avicennia marina, which has an ecologically successful Importance Value Index (IVI) of 157.29 and is most resistant to biotic and abiotic stresses, while others are susceptible to environmental stress and gradually shrink. The results exhibited significant diversity and distribution in partially protected areas. In severely degraded areas, A. ilicifolius grows in abundance, indicating secondary succession.

Keywords: Diversity, Growth parameters, Mangroves, Partially protected and disturbed habitats, Quadrate study, Thane creek, India