Coastal Greenbelt is a measure to prevent coastal erosion and reduce other natural hazards by planting trees and creating forests along the coasts. The south and eastern coasts of Bangladesh face tidal surges and erosion every year. It has been determined that the main protection against tidal surges will not come from the so-called strip planting but from largescale non-raised foreshore and charland mangrove planting. Planting along roads and embankments contributes to the establishment of a greenbelt and plays a role in coastal protection, but a greenbelt has other positive effects too.
A greenbelt has two main functions: 1) to protect the embankment from tidal surges through plantings on its outer slope, and 2) to protect life and property in the region by embankment plantings as well as planting in the agricultural hinterland. It also enhances environmental quality. Moreover, it restores and protects the important mangrove forest. It also increases the country's forest resources through perennial vegetation on sea or river embankments.
The coastal areas of Bangladesh are prone to severe damage from cyclones. In 1991, a devastating cyclone with winds exceeding 200 kilometers (km) per hour and a tidal surge of 6 meters (m) struck Bangladesh. About 140,000 lives and about $240 million worth of public infrastructure alone were lost. This and previous cyclones proved that dense forest cover along the coastline, particularly wide belts of mangrove plantations such as those found in the Sundarbans (a large natural mangrove area in the southwestern part of Bangladesh) and other coastal areas, are an effective buffer against the impacts of cyclone. After the cyclone, the government of Bangladesh took up an afforestation project to establish a greenbelt in the coastal regions of the country.
The Project was formulated from September 1993 to March 1994 and approved by the Asian Development Bank (ADB) on 2 March 1995. The Loan Agreement was signed on 18 April1995. The Project was declared effective on 28 July 1995 and closed on 31 December 2002. It consisted of seven components: (i) embankment, roadside, and rail-side plantations; (ii) homestead and institution plantations; (iii) trial foreshore plantations; (iv) nursery development and upgrading; (v) research support; (vi) training programs; and (vii) public awareness campaigns.
A total of ten forest divisions have been included in this project. These are: Patuakhali forest division (comprising Barguna and Patuakhali districts), Chittagong forest division (comprising Chittagong and Cox's Bazar districts); Bhola forest division; Lakshmipur forest division; Noakhali forest division; Feni forest division; Pirojpur forest division; Bagerhat forest division; Barisal forest division; and Jhalokati forest division. In the process, around 3 million ha of land, constituting about 16-17% of the country';s total land area, have been covered.
Forest plantations were to be established along 1,300 km of riverine and coastal embankments belonging to the Bangladesh Water Development Board (BWDB). By project completion, 1,394 km of plantations were established mainly on riverine embankment.The targets for railside and roadside plantations were (i) 20 km of rail-side land owned by Bangladesh Railways; (ii) 420 km of national highways and type-A feeder roads owned by the Roads and Highways Department; (iii) 280 km of type-B feeder roads of the Local Government Engineering Department; and (iv) 4,000 km of rural feeder roads under district, thana (subdistrict) and union councils. The Project's physical accomplishments were significantly higher—838 km of national highways, type A feeder road and rail-side plantations, and 6,702 km of type B and rural feeder road plantations. Although a direct comparison of actual outputs and appraisal targets was not possible, it is clear that the actual outputs significantly exceeded the targets.
The Project achieved and exceeded the physical target of establishing plantations, which helped improve the coastal environment. It also raised the public's awareness of the benefits of tree planting.The foreshore plantation component, if expanded, could have contributed towards creating an effective buffer against the impact of cyclones and storms.
Sidr hit Bangladesh on November 15, 2007 with winds of 260 km/h (160 mp/h), which would make it a Category-5 equivalent tropical cyclone on the Saffir-Simpson Scale.Coastal districts of Bangladesh faced heavy rainfall as an early impact of the cyclone. The damage in Bangladesh was extensive. Some local officials have described the damage as being even worse than that from the 1991 cyclone. The entire cities of Patuakhali, Barguna and Jhalokati District were hit hard by the storm surge of over 5 meters (16 ft).About a quarter of the Sunderbans were damaged. Researchers said mangrove forest Sunderban will take at least 40 years to recover itself from this catastrophe.It did kill 3,447 people, but this was much less than the 140,000 that died in 1991.Cyclone walls planted within trees are in place to protect vulnerable areas from storm surges. It is mandatory to take measures for the development of coastal greenbelt in order to minimise the impacts of cyclones in coastal regions of Bangladesh. [Masud Hasan Chowdhury, Md Tuhin Molla and Sanzida Murshed]