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The Sleepless Sentinel

‘Sundari’ on the verge of extinction from Indian Sundarbans!
Fight for survival continues for 'Heritiera fomes'

Samik Gupta, NINB, Jhilla, Sundarbans: In the past few decades’ human activities have caused unprecedented damage to Mother Nature and the earth environment is suffering immensely. This impacts everyone for the simple reason that we all end up footing the bill and there is no escape from it. Every species in nature is interdependent and connected to each other which conducts the smooth flow of survival. Disruption of any of the forces binding this intricate web of life brings about a series of complications which ultimately leads to the extinction of species.

If one can truly quantify just how much expensive the devastation of nature really is. Its time we shift out attention to the ‘Sundari‘, Heritiera fomes. Once found abundantly in the ‘Sundarbans’, the sundari now faces an extremely high risk of extinction largely due to human intervention.

HABITAT & THE DANGER CAUSED TO IT

The Sundari, Heritiera fomes is phylo-genetically a very ‘moody’ plant. It shrinks if the habitat is hostile and blossoms in a very specific landscape. This Halophytic plant needs higher amount of fresh water flow with a lower percentage of salinity (5-15 psu). It grows in areas where a river merges with the sea at a distance of 50–100 km approximately. Unfortunately this fresh water has decreased from the sundarbans where once there was no dearth of it. In 1970s, construction of the Farrakka dam at Bhagobangola, Murshidabad district by Indira Gandhi government acted like the final nail in the coffin!

How worse is it? If a dam is constructed upon a river as Ganges and Padma basin then it restricts the flow of the fresh water which is one of the key components for its survival. A heap of sand accumulates due to the restricted flow of water which ultimately reduces the depth of the river. Due to this mechanism, fresh water rivers like the Ganges, Padma, Hoogly and their tributaries are facing the same crisis which our rulers and scientists failed to anticipate. One example of this is the critically endangered ‘Sundari ‘plant!

Apart from manmade devastation, the nature takes its own course which sometimes results in the tectonic movement or the tilting effect making the lower valley of the Ganges tilt towards the east from the west which is obviously beyond human grasp. But the fact remains that it is us who poses the greatest survival threat to all the living creatures of the earth!

THE CRISIS- Low fresh water, High Salinity

Due to Farakka dam, the Padma and the Ganges has disconnected from the Sundarban Rivers as Matla, Goasaba,Thakuran, Jamira, Shoptomukhi, Baratola etc. The fresh water flow to the Hoogly has also reduced. The mighty river Malta has reduced to become a dying water channel, which once allowed huge ships, now trails with smaller country boats only! Due to decrease in fresh water flow, Sunderban has witnessed a sudden intrusion of marine backwater in the river basins, especially on its western part. The 24 Pargana (S) district is mostly affected out of it and the Practical Salinity Unit (psu) is on a steady rise! The psu is considerably low in Jammudip in comparison to Shoptomukhani, though both the areas are situated at the western side of Sundarban. According to researchers, total practical Salinity Unit present in the waters of west Sundarban has reduced by 16.5% in the last 24 years. Therefore, a sensitive plant as Sundari cannot survive in such uncertainty. On the other hand, Central part of Sundarban speaks a different story. The river courses of Thakuran, Dhulibhasani, Chulkati, Goashaba, Malta, Pirkhali contain extremely higher percentage of salinity, which posses 'Sundari' impossible to grow! Whereas, the eastern part of Indian Sundarbans, located closest proximity to Bangladesh offers a lower percentage of salinity. Researchers say, forests such as Jjila, Arabeshi, Horinbhanga, Burirdabri , Khatuwajhuri and some parts of Chandkhali has witnessed a drop of 22 psu in salinity in the last 24 years. Hence, it's safe to conclude that the Eastern part of the sundarbans has a much favorable condition for 'Sundari' in comparison to its eastern counterpart.

SUNADARI & BANGLADESH

A research team from Dhaka University has sought a clearer picture on the status of 'Sundari' at Bangladesh Sundarban, pulling together data from enormous range of sources. Prior to the construction of the Farakka dam, scientifically they divided Bangladesh Sundarbans into two parts viz. the 'freshwater region' and the 'moderately salt water region'. But after the dam was constructed in India, they added a third region and named it 'salt water region'. Although, the area of earlier two zones were almost same in size. Later it changed to 60% of Saline zone (newly added zone-3), moderate saline zone 35% (earlier zone-2) and fresh water only 5% (earlier zone-1). Their findings also include the survey of 6 important sites where the number of Sundari is only 1375 in number! Tambulbunia (606), Moroghodra (550) Patkoshta (105) Tek (100) Arpongashiya (10). What is alarming is, in 1959 the percentage of the specie was 31.6% which later decreased to 21.01% in the year 1983! Hence, these statistics are clear signs that the existence of Sundari in Bangladesh is remarkably low. But still better than India. This issue has grabbed the attention of Bangladesh government as well. But it is Dhaka University which has played a important role in conducting relevant research by the help of modern GIS system (Geographic Information System). Their valuable research shows that the density of Sundari has reduced by 6620.12 hectors in Bangladesh in three decades i.e. 1989, 2000 and 2010.

WORLD SCENARIO

It has already been discussed that the Sundari has some unique characteristic features. It grows and vanishes in areas, as it wishes. What is unusual amongst 112 mangrove holding countries of the world is that Sundari is found in only 5 countries of the world! Their distribution ranges from India, Bangladesh, Malaysia, Thailand and Myanmar amongst which it has its origin only in Irrawaudi in Myanmar and the Sundarbans of India and Bangladesh.

According to the IUCN assessment 2008, Sundari was declared endangered in 2010 and accordingly made its way to the ‘Red Data book'. In earlier times, it was mostly grown in Malaysia but 50-60% of Sundari forest disappeared in the last 60 years. Extensive Shrimp cultivation, development of coastal areas, increasing timber demand and agricultural expansion has contributed a lot behind the ground reality. Shrimp cultivation is a very crucial issue where numerous small ponds and water bodies are cut to be filled with saline water, especially in the fresh water areas which are ideal for the growth of the plant. As a result, the salinity in the entire area has elevated relatively! Thailand faces a similar crisis, on top of tourism and coconut cultivation. Even if sundari continues to grow in Bangladesh and India, It’s strictly concentrated to certain areas, making it critically endangered specie. In India, Sundari is found in only six out of every 100 mangrove trees, if not less. The world scenario of its existence is pitifully low. And we are negligent enough to do nothing about it!

TOP DYING DISEASE- HOW IT AFFECTS SUNDARI

Apart from the above mentioned reasons, there are two other reasons behind its disappearance. One of them is the ‘Top dying disease’. A kind of outbreak which is seen only in Sundari amongst other trees. Seed like in form, it infests in the lower portion of the leaves and gradually spreads to the entire tree or plant. Eventually the plant dries out and the disease spreads like epidemic on the whole area. Even scientists are at a complete loss to explain its cause. Some say it happens due to the heavy metallic particles present in the air. But then again, its mere conjecture. As well as its atmospheric tolerance is relatively low. The Sundari is of immense importance in nature therefore battling this ‘top dying disease ’will require thorough researches with greater attention to‘ phylogenetics and ‘species life’ factors as well. India and Bangladesh should take additional initiatives so that we stand a chance at its reintroduction.

ELEVATED WATER LEVEL- THE FIGHT FOR EXISTENCE

The elevated level of marine water is one of the greatest causes of concern for the specie. In between development at the upward areas and elevated water level on the other hand, ‘Back mangrove’ specie like Sundari finds it difficult to reestablish itself in different habitat. The occurrence of different mangrove species depends upon the elevation of that particular area. Any exception to this rule can destroy specie in a matter of time. This phenomenon is described by Ellison (2005) as ‘Morality at present locations and re-establish at higher elevations in areas that were previously landward zones.

There is no definite solution to a crisis like this. Sunderban has witnessed this phenomenon many times specially in the case of Dhani grass, Portericia coerktata. Specific conservation program is needed along with some site specific micro planning even by relocation of any developmental program takes place in their habitat and any new proposal should be turned down. Because it has tremendous medicinal value, which is far from being fully discovered.

MEDICINAL VALUE

A literature survey revealed that H. fomes possesses significant pharmacological potential and chemical constituents which rural people living in the Sundarbans use to treat a wide spectrum of human ailments. Leaves and seeds are reported useful for the gastrointestinal disorders as diarrhea, dysentery, constipation, acidity, indigestion, and stomach ache. The bark and stem are well-reputed remedies for diabetes and skin diseases (dermatitis, eczema, boils, abscess, acne, sores, and rash). Local people use twigs to clean teeth and relive cough. Several in vitro studies established that the plant possesses significant antioxidant, antinociceptive, antimicrobial, antidiabetic, and anticancer actions. In spite of having such promising biological and pharmacological potentials, there are only few reports available on this plant Therefore, it has become all the more necessary to accumulate this indigenous knowledge by proper documentation and preserve it for future research so that all parts of Heritiera fomes are used in the treatment of different ailments.