The pre-tsunami status of coastal trees and forest resources and the forestrelatedimpacts of the tsunamiReportedly the coasts of Bangladesh and West Bengal in India were not affected by the tsunami of2004 as the sea was at low tide. As in other parts of the world, mangrove habitat degradation isevident. Despite a long history of management the Sundarbans is said to be experiencing degradation— a decline in crown density and change in vegetation composition in favour of less valuable seralspecies (Excoecaria agallocha) are well-established facts. Causes are probably attributable to changesin the physical environment (e.g. changed sedimentary condition, increased salinity) andoverexploitation of resources. Along the southern margin, the forest is shrinking owing to waveinducederosion. During the 1980s the entire Chakaria Sundarban was converted into shrimp ponds onthe grounds that the substrate in the area was too saline to support productive mangrove forest. Thescattered fringe mangrove along the eastern part of the coast is not under any management and isdisappearing rapidly due to shrimp pond conversion.Plantations are generally in good condition and early plantations are now approaching maturity.However in places, they are subject to degradation and encroachment. A second generation ofplantation needs to be established to sustain the shelterbelt along the coast.The urgent need to rehabilitate these natural and planted mangroves and develop forestry practices toestablish second generation mangrove plantations is appreciated by the government and steps havebeen taken accordingly.Implementation of coastal forest rehabilitation: Issues that have emerged andlessons learnedThe Sundarbans Forest Department has implemented rehabilitation programmes such as AssistedNatural Regeneration (ANR, 5 000 hectares) and Enrichment Planting (EP, 10 000 hectares) under theSundarbans Biodiversity Conservation Project with financial assistance from the Asian DevelopmentBank. The success of these programmes is highly variable and generally they can be viewed asunsuccessful. The main reason for this failure has been inadequate knowledge about ecologicalprocesses in the mangrove habitat. For the rehabilitation of degraded mangrove plantations, which arepresently thought to be unsuitable for mangroves, the Bangladesh Forest Research Institute (BFRI) hasworked over the last two decades to select appropriate species. The development of a second
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