WFM 6311 CLIMATE CHANGE RISK MANAGEMENT

PROBABLE IMPACT ON BIODIVERSITY OF SUNDERBANS DUE TO SEA LEVEL RISE

PRESENTED BYEMDAD YUSUF – 1009282010

MD. ASHFAQUR RAHMAN – 1009282013

Background of the study:

• “Royal Bengal Tigers may go extinct by turn of century - reveals study” says a report by prominent English daily THE DAILY STAR, on 1st March’2010. The report also said, “The Royal Bengal Tigers, one of the world’s largest big cat populations, could disappear by the end of this century as rising sea levels caused by climate change destroy their habitat along the Sundarbans coast.”

• Sundarban is the single largest block of tidal halophytic mangrove forest in the world noticeably rich in terms of plant and animal diversity The number of species found is nearly as many as those reported for Malaysia and Indonesia (CHAPMAN, 1976).

• It is also a center of economic activities, such as extraction of timber, fishing and collection of honey.

• More interestingly, the Bangladesh and Indian portion of the forest are listed in the UNESCO world heritage list separately as the Sundarban i.e.the “beautiful forest” and Sundarban National Park respectively, though they are simply parts of the same forest.

• Unless immediate action is taken, The Sundarbans, its wildlife and the natural resources that sustain millions of people may disappear within 50 to 90 years.

This satellite image shows the forest in the protected area. The Sundarbans appears deep green, surrounded to the north by a landscape of agricultural

lands, which appear lighter green, towns, which appear tan, and streams, which are blue

Objective of the study

• To understand the biodiversity of Sunderban

• To asses the impact on biodiversity due to sea level rise

• Possible actions to combat the situation

SUNDARBAN: GEO-ECOLOGICAL PROFILE

• The forest floor is 0.91m to 2.11m above mean sea level.• The soil is a silty clay loam with alternate layers of clay, silt and

sand. The clay surface is clay except on the seaward side of islands in the coastal surface limits, where sandy beaches occur.

• Rivers in the Sundarbans are meeting places of salt water and freshwater.

• It is intersected by a complex network of tidal waterways, mudflats and small islands of salt-tolerant mangrove forests, and presents an excellent example of ongoing ecological processes.

• Sundarbans is divided into three distinct ecological zones namely Oligohaline zone (salinity < 6,250 micromhos)

mesohaline zone (6,250 < salinity <12,500 micromhos ) Polyhaline zone (salinity >12,500 micromhos)

Biodiversity of Sundarban:

• Largest diversity of mangrove plants on the Globe characterized by a very dynamic environment due to characterized the effect of tide, flooding, salinity, and cyclones.

• Only this mangrove area on earth inhabited by man-eating tigers

• The forest has a unique biota comprising:• 334 species of plants• 49 species of mammals• 400 species of fish• 320 species of birds• 53 species of reptiles• 11 amphibian species• Numerous invertebrates, phytoplankton, fungi, bacteria,

zooplankton, benthic invertebrates, mollusks etc.• At least 37 species of 'obligate' mangrove plants, 127 species of

euryhalinefish, a total of 1287 animal species comprising 873 invertebrates, 1 species of Hemichordata, and 413 species of vertebrates

Importance of Sundarbans:

The major forest products of Sundarbans

• Timber and industrial raw material.

• Fuelwood.• Thatching material.• Non-wood forest products

Tourism• Conservation tourism

or ecotourism may be developed for the Sundarbans without causing undue disturbance to the forest and wildlife

• The fishing operation during winter months can also be developed as an interesting tourist spot.

Wildlife Sanctuaries

•There are three wildlife sanctuaries established in 1977 under the Bangladesh Wildlife (Preservation) Order, 1973 (P.O. 23 of 1973)•The World Heritage Committee of UNESCO has declared the Sundarbans as its 522nd World Heritage Sitefor its outstanding scenic beauty and biological traits

Sea level rise

Year 2020 2050 2100

Sea level rise 10 cm 25 cm 1 m (high end estimate)

Land belowSLR

2 % of land(2,500 km2)

4 % of land (6,300km2)

17.5% of land (25,000 km2)

Ecosystem Inundates 15% ofthe Sundarbans.

Inundates 40% of theSundarbans.

The Sundarbans wouldbe lost.

Salinity Increase Increase Increase

Sea level rise in Bangladesh and its potential impacts

Sea level rise (contd.)

Tidal Station

Region Latitude (N)

Longitude (E)

Datum (m) Trend

(mm/year)Hiron Point Western 21048' 89028' 3.784 4.0Char Changa

Central 22008' 91006' 4.996 6.0

Increase of tidal level in two coastal stations of Bangladesh coast

Sea level rise Potential impacts10 cm25 cm45 cm60 cm1 metre

•will inundate 15% of the Sundarbans•will inundate 40% of the Sundarbans•will inundate 75% of the Sundarbans•will inundate the whole Sundarbanswill destroy the whole Sundarbans

Fate of the Sundarbans with different sea level rise

Impacts due to sea level rise:

• The main impact of sea level rise on water resources is the reduction off fresh water available due to salinity intrusion. Both water and soil salinity along the coast will be increased with the rise in sea level

• Increased salinity will change the habitat pattern of the forest. Sundari, the most typical kind of tree in the Sundarbans is thought to suffer from top dyeing disease because of increased salinity (Kausher et al., 1993).

• Aquatic organisms will migrate inward, because of increased salinity too• As a consequence of salinity penetration in the Sundarbans, majority of the

mesohaline areas will be transformed into polyhaline areas, while oligohaline areas would be reduced to only a small pocket along the lower-

Bales war river in the eastern part of the forest. (Ahmed, et al. 1998).

Impacts due to sea level rise (contd.)

• The resultant increase in salinisation and accretion of sediments may alter vegetation composition. Impacts on animal communities may also occur due to both, the direct effects of salinity and indirectly through food chain modifications caused by the alterations in the nature and amount of detritus available in the mangrove ecosystem, which is directly a threat to the living bio-diversity.

• Eventually the species offering dense canopy cover would be replaced by non-woody shrubs and bushes, while the overall forest productivity would

decline significantly. The degradation of forest quality might cause a gradual depletion of rich diversity of the forest flora and fauna of the Sundarbans ecosystem

• Natural habitat will be destroyed due to inundation

How to combat the situation

• Designing and establishing sea-level / climate modeling network• Establishing databases and information systems • Data collection of Sundarbans' resources and their uses • Integrated coastal and marine management• Monitoring the impact of climate change on coral reef, Royal Bengal

Tiger, crocodiles and Sundari tree• Coastal vulnerability and risk assessment• Economic valuation of Sundarbans' resources • Improving catchment management• Afforestation and reforestation by salt tolerant species• Strict control of Tigers' poaching

How to combat the situation (contd.)

• Facilitating natural regeneration and natural succession of native tree species

• Increasing waterfront setbacks in beach front areas • Education on climate change and emergency

preparedness needs to take place at all levels by incorporating it into education curriculum

• Creating public awareness through mass media• Developing coastal infrastructure• Initiating community based coastal forestation• Protecting existing mangroves against

encroachment and cutting• Establishing mechanisms to promote carbon uptake• Raising funds for conservation programme.

Thanks for hearing us and hope it was not bad

Lets save the tigers