Challenges, opportunities, and climate change adaptation strategies of mangrove-agriculture ecosystem in the Sundarbans, India: a review

The mangrove-agriculture system is a distinct ecosystem that evolved in the Sundarbans, India in the last century due to anthropogenic activities and climate change consequences. Degraded-mangrove and agriculture (rice-based systems and aquaculture) exist side by side, each having their specific challenges and opportunities. In this review, we analyzed challenges faced by this unique ecosystem along with opportunities derived from technological advancement and site-specific climate change adaptation strategies. Both the mangrove and lowland rice ecosystem could act as carbon (C) sink to the tune of 27 and 0.93 t ha(-1) per annum, respectively. Apart from C sequestration, mangrove-rice systems provide many ecosystem services. However, 40% of tropical and 10.5% of Sundarban mangroves (between 1930 and 2013), have been lost due to climate change induced sea-level rise, extreme weather events and human interferences. The specific challenges in this system are freshwater scarcity, high salinity, insufficient real-time seed supply, poor fertilizer-management, lack of irrigation network, and unprecedented occurrence of extreme events which seriously hamper the productivity of mangrove, rice, and aquaculture. There also exist some unique opportunities in terms of cheap labour availability, mangrove-conservation acts, cheap river-communication, and scope of ecotourism which fortunately get the attention of national and international funding agencies. In the last section of this review, we recommended ten climate change adaptation strategies that may be considered at the policy and farmer levels. The strategies broadly include the development of small-scale rainwater harvesting structures in series, the introduction of salt tolerant cultivars with water management, land shaping, establishment of multipurpose cyclone shelter at each block and empowerment of women through self-help groups.

Automated summary

The mangrove-agriculture system in the Sundarbans region is a unique ecosystem facing challenges like freshwater scarcity, high salinity, and climate change, while presenting opportunities such as cheap labor and mangrove conservation. Both mangrove and rice ecosystems act as carbon sinks and provide ecosystem services, but climate change adaptation strategies are needed to protect them.