Decadal loss of above-ground biomass and subsequent potential CO2 emission from the Sundarbans mangrove ecosystem, India

Abstract

Mangrove forests harbour some of the highest carbon densities of any ecosystem, yet their decline has resulted in potential carbon dioxide (CO₂) emissions. The emission of CO₂ due to the loss of above-ground biomass (AGB) of the Sundarbans mangrove ecosystem was calculated using the ArcMap and ERDAS software. Hence, classification of the Satellite images between 1990 and 2020 of the Indian portions of the Sundarbans was done.

The total loss of mangrove area in the Indian part of Sundarbans is 138.4 km² in the last 30 years. Around 57% of the total loss is due to erosion, 22% is converted to fallow lands, and the remainder is transformed into different landforms for human use. The AGB loss has led to the potential CO₂ emission of 2028.4 ± 713.7 Gg, which costs $101.42 million in terms of the social cost of carbon (SCC).

The stability analysis of the system showed that the fluctuations during the high tidal surges of cyclone ‘Aila’ that struck the coastline of the Bay of Bengal, resulted in the decrease of mangrove covers and acted as a driving force behind the depletion of ‘blue carbon’ of the Sundarbans.