Kolkata: What saves Kolkata and its hinterland time and again during every major cyclone? The Sunderbans.
The dense mangrove forests of the world’s largest delta region truly act as a buffer to all major cyclonic storms that form in the Bay of Bengal and hit the Bengal coast. Had the mangrove forests not been there, environmentalists have time and again said, the cyclones with some amount of severity would have battered Kolkata and its adjoining areas, time and again.
But, the fragile delta region has been under threat for some time now and subsequent dispensations have not taken matters seriously enough. The result, the scale of devastation during last year’s very severe cyclonic storm Amphan was telling on Kolkata. Interestingly, West Bengal Chief Minister Mamata Banerjee had inaugurated an ambitious plan to plant 50 million mangrove plants after the devastation caused to the delta region, post-cyclone Amphan in 2020. But, many environmentalists had simply said the plan was ‘over ambitious’.
A simple calculation suggests that the Chief Minister’s plans were really over-ambitious. Experts say around 5,000 mangroves can be planted on one hectare of land and that is an outside limit. And with that outstretched limit, to plant 50 million plants, around 10,000 hectares of land or a little over 100 sq km would have been required. Roughly put, that is approximately half of the size of Kolkata city.
“It was an impractical decision to plant such a large number of trees in one go. Planting of mangroves in the chars (silted islands) as well as along the meandering rivers in the delta region requires special skills. It is only space, but the tidal rivers and rivulets change the soil support system everyday. Salinity factors and wind patterns have to be taken into account before any afforestation in the Sunderbans. Mere planning a large volume of trees will never solve the problem,” said a Kolkata-based environmentalist.
