Optimal mangrove restoration through community engagement on coastal lands facing climatic risks: The case of Sundarbans region in India

摘要

Restoration of mangrove forests through community involvement offers the promise of reaping multiple environmental dividends while simultaneously helping local communities augment their livelihoods through generating payments from ecosystem services. However, there exist several challenges to the success of such restoration projects. In this paper, one such key challenge, that of the risk of extreme climatic events, is considered. Optimal rate of mangrove restoration on public coastal lands is derived in the presence of a future risk of extreme cyclones decimating the mangrove forests. Using the context of the Sundarbans region of India, which has the largest mangrove forests on the planet, we develop a model of community led restoration efforts where local inhabitants receive credit for carbon sequestered in the process. Results indicate that when communities do not receive outside support through wages or reimbursement of plantation costs, restoration efforts get spread over a longer time horizon. Presence of a risk of future cyclone events that could destroy the restored forests prompts speedier restoration, which may not be an optimal outcome from the perspective of global carbon mitigation efforts. An optimal plan that is primarily concerned with deriving sequestration benefits from newly restored mangroves leads to lower restoration levels in the presence of higher cyclone risks. However, irrespective of the institutional setting under which restoration is incentivized, given the relatively stable nature of underground carbon stored in mangroves, it is optimal to undertake higher restoration efforts when climatic risks are low.