Dynamics of mangrove diversity influenced by climate change and consequent accelerated sea level rise at Indian Sundarbans

Abstract

Sundarbans, the largest contiguous mangrove forest of the world, regularly bears the brunt of numerous cyclones/storm surges. The frequencies of these disasters are ever increasing, in wake of the twin predicaments of sea level raise and climate change. This temporal study (2008-2013) at Jharkhali Island, delve into the dynamics of mangrove community in response to seasonal and yearly alterations in river-water salinity, due to the severe cyclone AILA (2009) and sea level raise. Raise in water salinity accentuates the abundance of salt tolerant species with physiological and phenological adaptations (Avicennia marina, Suaeda maritima) and decreased abundance of salt sensitive mangroves (Rhizophora mucronata). Exclusion of few mangrove species (Aglaia cuculata, Brownlowia tersa, Heritiera fomes, Kandelia candel and Nypa fruticans) is also evident, facilitating the proliferation of resistant, opportunistic and invasive flora (Clerodendron inerme, Derris trifoliata and Phoenix paludosa). Solutions have also been suggested in the light of the modern conservation paradigm.