Mangroves of the Lower Gangetic Delta

The Lower Gangetic Delta, encompassing the mangrove-dominated Sundarban region, is one of the world’s largest river deltas, formed by the Ganges, Brahmaputra, and Meghna rivers. Spanning 9630 km2 across the Indian part, it houses the Indian Sundarban Biosphere Reserve. This reserve, divided into western, central, and eastern sectors, experiences varying salinity levels that significantly impact biodiversity. Salinity influences mangrove growth and fish populations, exemplified by the critically endangered mangrove species, Heritiera fomes. Mangroves in Sundarban delta play a crucial role in carbon dynamics due to their high carbon storage potential. The chapter emphasizes optimizing the ambient aquatic salinity to enhance carbon sequestration by mangroves. Porteresia coarctata, a saltmarsh grass, noted for considerable carbon storage thrives in diverse salinity ranges, aiding ecological succession on new land masses. Mangrove associates like Suaeda and Salicornia are resilient to high salinity, suitable for halophyte farming, and can convert underutilized lands into productive carbon sinks, offering ecological and financial benefits, including carbon credits. However, the Sundarban mangroves face threats from deforestation, pollution, climate change, and overharvesting. Natural events and human activities, such as greenhouse gas emissions and overexploitation of natural resources, exacerbate these threats, endangering the ecosystem’s stability, vital for coastal protection and carbon storage.