Estimation of sequestrated carbon and its valuation using geospatial technology in Sundarbans biosphere region, India

The Indian Sundarbans, a UNESCO world heritage site, is a unique mangrove landscape that supports millions of livelihoods and plays a crucial role in carbon sequestration. Carbon sequestration is a vital ecosystem service provided by nature. The study area under investigation has been formed through the Ganges river sedimentation, and the area is also part of the Holocene delta. Carbon sequestration, being identified as a critical regulating service, plays a significant role in attenuating the impact of climate change. Considering this fact, the study assesses carbon sequestration in the Sundarbans Biosphere Region (SBR), India, using a non-GIS-based InVEST model to estimate carbon values for 1990, 2000, 2010, and 2020, and projects future values for 2030, 2040, and 2050 by integrating land use changes with the Markov model. Carbon sequestration potential varies significantly across landscapes, with the maximum observed in mangrove forests (2828.97 metric tonnes) and the minimum in water bodies. Social carbon cost value is also calculated following IPCC guidelines. Temporal changes show a shifting distribution of high carbon values in the Sundarbans mangrove region. Application of spatial autocorrelation with Moran’s, I and hotspot analysis show a clustering of carbon-sequestered zones around the core mangrove areas and human-influenced cold spots in surrounding zones. The findings underscore the Sundarbans' vital role in carbon absorption and the need for sustainable management practices to maximise this ecosystem service for future carbon sequestration.