The roles of mangroves in sedimentation: A case study in Sundarbans, India

The Sundarbans, the southern part of the Ganges-Brahmaputra-Meghna Delta, exemplify the complex interaction between mangroves and sedimentation, with a notable annual loss of about 2 sq. km of mangroves and land, especially during post-monsoon and bore tides. Nevertheless, alterations in the sediment dispersal system within the Hooghly River, coupled with various anthropogenic activities, are substantially modifying the dynamic system response of the Indian Sundarbans and, consequently, the role of the mangrove ecosystem in sedimentation, which contradicts the existing literature. Remote sensing analysis from 1922 to 2022 showed that a tidal bar on the Hooghly River's bed lost 1.50 sq. km since 1972 but gained 0.79 sq. km of mangroves. The mangrove proportion increased from 5.29% in 1972 to 51.05% in 2022. The study suggests mangroves might indirectly cause erosion, highlighting the need for sustainable monitoring and urgent conservation efforts to protect this vital ecosystem.