Brief Context
Context A recent study shows that around 10–15 percent of the Sundarbans is undergoing a “critical slowing down” process from environmental stress. Sundarbans The Sundarbans is a UNESCO World Heritage Site and is ecologically significant. The worlds largest mangrove forest, spread across the delta formed by the Ganges, Brahmaputra, and Meghna rivers on the Bay of Bengal.
Source Content
Source: GS3/ Environment
Context
- A recent study shows that around 10–15 percent of the Sundarbans is undergoing a “critical slowing down” process from environmental stress.
Sundarbans
- The Sundarbans is a UNESCO World Heritage Site and is ecologically significant.
- The world’s largest mangrove forest, spread across the delta formed by the Ganges, Brahmaputra, and Meghna rivers on the Bay of Bengal.
- Shared between India (40%) and Bangladesh (60%).
- Key rivers flowing through this area include Muriganga, Raimangal, Harinbhanga, Saptamukhi, Thakuran, and Matla.
Key Findings
- Climate: Rising temperatures are reducing species richness and weakening ecosystem stability. Freshwater flow and rainfall matter because reduced freshwater increases salinity. Thus, rainfall plays a role in reducing salinity and improving growth conditions. However, erratic rainfall and extreme weather events are disrupting this balance.
- Ecology: The forest includes both fast-growing species like Avicennia officinalis and Excoecaria agallocha. It also includes slow-growing species such as Heritiera fomes, Bruguiera sexangular, and Xylocarpus mekongensis.
- Decline in canopy height and leaf traits is reducing structural complexity.
- Forests are becoming more uniform with fewer species, reducing biodiversity.
- Some parts of the forest are shifting from a carbon sink (absorbing carbon dioxide) to a carbon source.
- Cyclones as Factor: Major cyclones such as Sidr, Rashmi, and Aila of the Bay of Bengal have significantly reduced forest resilience.
- Large areas shifted from high resilience (strong recovery capacity) to moderate and weak categories.
- Affected Zones: The most affected regions are in the central and south-eastern Sundarbans (seaward and cyclone-prone areas).
- In India, the western Sundarbans show lower resilience compared to Bangladesh, especially near northern boundaries.
Way Ahead
- The Sundarbans is vital for biodiversity, coastal protection, and carbon storage (absorption of atmospheric carbon dioxide).
- Declining resilience threatens ecosystem stability, livelihoods, and climate regulation functions.
- Protecting mature trees is essential to maintain resilience.
- Strengthening patrolling can reduce illegal logging and forest degradation.
- Involving local communities can improve awareness and conservation efforts.
- Policies should integrate climate impacts (effects of climate change on ecosystems) for long-term protection.
Source: TH