Unlike Steinbeck’s defamed ‘salt-water-eating bushes’ of the Sea of Cortez, the Sunderbans are an excellent forest treasure for Bangladesh, India’s West Bengal, and the rest of the world. In 1997, UNESCO awarded the Sunderbans the accolade ‘A World Heritage Site,’ with the obvious implication that everything should be done to preserve this incredible wonder of nature, the world’s largest continuous mangrove stand. A decade ago, the part of the Sunderbans that belongs to West Bengal earned the same honor. The Sunderbans is a fascinating interface where the ocean and continent intermingle. If implemented, India’s National River Linking Project will perhaps annihilate this unique treasure with its diverse plant and animal species, including mangroves and Royal Bengal Tigers.
The Sunderbans, named after its dominant mangrove, Sundari is one of the first government-managed mangrove forests in the world. It is located at the lower Ganges delta. This is the largest delta in the world, formed by the outpouring of sediments over many million years by the Ganges, the Brahmaputra, and the Meghna Rivers. The delta building continues to have the world’s largest sediment load, almost one billion tonnes annually. The Sunderbans occupies 10,277 square kilometers of land and water. The eastern 60 percent is in Bangladesh, and the rest is in the West Bengal Province of India. Approximately one-third of this magnificent forest has distributaries, brackish marshes, and tidal estuaries. The Sunderbans is a protective barrier against coastal erosion, cyclonic storms, and tidal surges. It produces incredible amounts of food, building materials, and fuel for the surrounding communities. Many species of mammals, reptiles, birds, fishes, etc, inhabit this majestic forest. This forest is the largest remaining habitat of the celebrated Royal Bengal Tiger, which is now an endangered species.
The Sunderbans can be divided, based on salinity and plant ecology, into three zones, with overall dominance of the Sundari in the freshwater zone in the northeastern part, Gewa in the mild saltwater zone in the middle, and Goran in the saltwater zone near the coastline. All three prominent mangroves and another species, Nipa Palm, locally known as Golpata, grow throughout the forest, but their concentration and height depend on salinity. The Sunderbans have a wide variety of biota supported by a complex and dynamic eco-environment, the main sustenance of this system being the flow of freshwater by the distributaries of the Ganges-Brahmaputra-Meghna Rivers.
Imagine a world 70 million years ago, when the Indian tectonic plate was almost at the end of its arduous odyssey from the supercontinent, Pangea. Formidable dinosaurs were about to become extinct, and tigers, including other carnivores, began evolving from animals called miacids. After a long evolution, modern-day tigers have evolved in Asia, and early tiger fossils dating 500 thousand years BP have been found in China and Siberia. Almost 65 million years ago, mangroves appeared in the Indo-Malayan realm. Mangroves (dispersing through the ocean water) and tigers (roaming through the primordial land) took many million years to come to their present being in the Sunderbans. Human intervention in the form of India’s National River Linking Project threatens to undo this incredible crafting of evolution and destroy this superb ecosystem. Would it not also be a travesty against human dignity and a despicable act of infinite proportion?
The Sunderbans have undergone significant changes during the last 500 years because the Ganges changed its course three times. Before the 16th century, the trunk stream of the Ganges was the Bhagirathi and the Hooghly, the Bhairab being the main delta-building spillriver. In the 16th century, joining the Brahmaputra, the Ganges changed its principal channel to the Madaripur Course (Arial Khan River). From the 1830s to 1840s, the last course change took place. The Padma (combined Ganges-Brahmaputra) and Meghna joined to form the present trunk stream, Meghna, the main delta-building river. Meandering and changing course by a river are common in flat topography. However, this eastward shifting of the Ganges is due to the uplifting of the western Sunderbans relative to the global sea level. What is the cause of this uplifting? This is a natural process far beyond the domain of human intervention, and the leading cause is the isostatic imbalance of the Himalayan mountains and the Indian tectonic plate. This shifting has been responsible for the silting of rivers in the western Sunderbans and an increase in freshwater flow down the rivers in the Bangladesh part of the Sunderbans. Remember, this has been a natural process, not a man-made one. Nevertheless, this is a suitable model to assess the impact of freshwater flow on the Sunderbans’ plant ecology.
The Farakka Barrage across the Ganges, located roughly 18 kilometers from the Bangladesh border, became operational in 1975. Diverting the water flow to the Bhagirathi-Hooghly distributaries of West Bengal, India, has reduced the freshwater flow in the lower reaches of the Ganges through Bangladesh. This has led to the salinity intrusion a few hundred kilometers upstream during the dry season, changing the salinity regime of the Sunderbans. The immediate casualty is the Sundari mangrove trees of the Sunderbans. It is reported with depressing anguish from several places of less saline northeastern Sunderbans, where Sundari achieves its maximum height, that this majestic tree is dying with the blight, starting at its top. In several places, with the worsening freshwater flow to the forest due to India’s diversion at Farakka Barrage, Kolkata and other plant species are also being affected. The monsoon flood overflow cannot stop this pitiful decay of Sundari and other plants because the damage inflicted during the dry season is irreversible. Sundari’s progressive rot directly correlates to the eco-environmental change of the Sunderbans due to India’s water withdrawal at the Farakka point. Similar effects have been experienced in other countries like Pakistan and Vietnam. This damage is not stopping at Sundari but will ultimately extend its deadly tentacles to this forest’s entire biota.
Now, one can see the immensity of the impending doom if India’s National River Linking Project, envisioned by former prime minister Atal Bihari Vajpayee in 2002, is executed. This project will divert vast amounts of water from the rivers of Bangladesh. The already existing problems of the Sunderbans caused by Farakka Barrage will increase many-fold. The killer bite to Bangladesh’s agriculture, forestry, fishery, public health, livelihood, environment, and wildlife by this National River Linking project would be many magnitudes higher than that of the Farakka Barrage. According to this stupendous plan (with a price tag of more than $168 billion), India would dig 30 links connecting major rivers, including the Ganges, Brahmaputra, and the southern rivers of the Deccan Peninsula, and divert about 200 billion cubic meters of water per year for irrigating the arid western states and semi-arid southern states. This project involves diverting one-third of the water from the Ganges and Brahmaputra — all at a colossal cost to Bangladesh. The Indian province of West Bengal will not be spared as a collateral victim.
If the world community does not stop this naive and dangerous Indian plan, the enchanting Sundari-mangrove, the awesome Royal Bengal Tiger, and other beautiful species — nature’s incredible craftsmanship through many million years — will be lost in oblivion.
