Survival rate of mangroves: A proxy to assess ecosystem health

Abstract

Survival rate of mangroves is highly species-specific, which significantly varies between sites. It is observed that survival rate of <em>Sonneratia apetala</em>, <em>Aegiceros corniculatum</em>, <em>Bruguiera gymnorrhiza</em>, <em>Xylocarpus granatum</em>, <em>Nypa fruticans</em>, <em>Heritiera fomes</em> and <em>Derris trifoliate</em> is more in the western sector compared to the central sector of Indian Sundarbans. However, a completely reverse picture with higher survival percentage in the hypersaline central sector is observed for species like <em>Avicennia marina, Avicennia alba, Avicennia officinalis, Acanthus ilicifolius, Excoecaria agallocha, Phoenix paludosa, Ceriops decandra, Rhizophora mucronata</em> and <em> Aegialitis rotundifolia.</em> Salinity seems to be the major driver for mangrove survival. Survival percentages of mangroves seedlings and their transformation into adult forms can be a potential indicator of ambient environment particularly in context to salinity. Such approach can be of importance in the ecosystem health monitoring programme preferably for regions like Indian Sundarbans, where significant spatial variation of salinity exists.