199
flood season to the Bay of Bengal; it is three times the amount of borne by the
Mississippi River (Coleman 1969; Anwar 1988).
It is estimated that some 1.5–1.8 billion tons of sediment is denounced in the Bay
of Bengal per year (Nishat 1988; Rahman 1988) but Anwar (1988) and Jabbar
(1979) mentioned that the mighty rivers Ganges, Brahmaputra and Meghna transports about 2.4 billion tons of sediments annually to the Bay of Bengal. Curray and
Moore (1971) show an enormous sub aqueous delta beneath the Bay of Bengal
formed by the sediment derived from the Ganges-Brahmaputra-Meghna Rivers, the
Bengal Deep Sea Fan, and the largest deep sea fan in the world. Sediments deposited on top of the upper most peat are fluvial controlled. These are the sediments
deposited by the Ganges-Brahmaputra-Meghna rivers system (Islam 2001). Erosion
and accretion are common phenomena in the coastal zone, where nearly a billion
tons of sediment are brought by the rivers. About two thirds of these sediments are
discharged into the Bay of Bengal, while the rest contributes to the formation of new
land and islands (Iftekhar 2006). However river bank erosion is a severe problem.
The annual rate of erosion in the Meghna river estuary alone is around 3199 ha/year
(Islam 2016). Aspects of the sedimentary history of the Bengal Basin since Ca. 9000
years BP can be interpreted from data provided in this study.
It is undoubtedly true that the Ganges-Brahmaputra-Meghna system has been
carrying sediments from upstream and depositing them in the basin, but their depositional environment needs to be considered (Islam 2001). The Fig. 6.7 shows a
model of integration of coastal wetland water resources and ecosystem services in
the coastal region. Water related sectors such as agriculture, land use, water navigation sector, industrial sector, mangrove wetland ecosystems, forest sector, fisheries
and livestock and coastal community livelihood are directly dependent on coastal
wetland resources (Fig. 6.7).
Bangladesh produce with 1 million tons fisheries products, which is more than
twice Indian aquaculture production per capita, Nepal, Pakistan and Sri Lanka, lag
far behind. In the coastal Bangladesh aquaculture is emerging as a prime rural
industry, contributing to employment, food security, poverty reduction and export
earnings. Export of aquaculture products earn Bangladesh half a billion dollars per
year, making them the country’s second-biggest earner of foreign exchange after
textile. All these water resources sectors and sub sectors are inter-connected for
their own sectoral development and management. Therefore coastal water resources
sector is a potential sector in the coastal region and it is playing as a driving force of
sustainable development of the coastal region of Bangladesh.
In most development, water resources management and sustainable livelihood
discourses need for integration at different levels are recognized and emphasized
(Rahman 2003). The soil of the entire coastline is generally sediment deposit of the
GBM and other rivers. Such soils are fertile but recently it has been affected by high
salinity intrusion. It has been estimated almost half of the coastal arable land can be
classified as saline zone, within this saline affected areas such as the greater Khulna
and Patuakhali districts are being the most affected region in the coastal region of
Bangladesh (Jalal 1988).
6 Degraded Coastal Wetland Ecosystems in the Ganges-Brahmaputra Rivers Delta…
flood season to the Bay of Bengal; it is three times the amount of borne by the
Mississippi River (Coleman 1969; Anwar 1988).
It is estimated that some 1.5–1.8 billion tons of sediment is denounced in the Bay
of Bengal per year (Nishat 1988; Rahman 1988) but Anwar (1988) and Jabbar
(1979) mentioned that the mighty rivers Ganges, Brahmaputra and Meghna transports about 2.4 billion tons of sediments annually to the Bay of Bengal. Curray and
Moore (1971) show an enormous sub aqueous delta beneath the Bay of Bengal
formed by the sediment derived from the Ganges-Brahmaputra-Meghna Rivers, the
Bengal Deep Sea Fan, and the largest deep sea fan in the world. Sediments deposited on top of the upper most peat are fluvial controlled. These are the sediments
deposited by the Ganges-Brahmaputra-Meghna rivers system (Islam 2001). Erosion
and accretion are common phenomena in the coastal zone, where nearly a billion
tons of sediment are brought by the rivers. About two thirds of these sediments are
discharged into the Bay of Bengal, while the rest contributes to the formation of new
land and islands (Iftekhar 2006). However river bank erosion is a severe problem.
The annual rate of erosion in the Meghna river estuary alone is around 3199 ha/year
(Islam 2016). Aspects of the sedimentary history of the Bengal Basin since Ca. 9000
years BP can be interpreted from data provided in this study.
It is undoubtedly true that the Ganges-Brahmaputra-Meghna system has been
carrying sediments from upstream and depositing them in the basin, but their depositional environment needs to be considered (Islam 2001). The Fig. 6.7 shows a
model of integration of coastal wetland water resources and ecosystem services in
the coastal region. Water related sectors such as agriculture, land use, water navigation sector, industrial sector, mangrove wetland ecosystems, forest sector, fisheries
and livestock and coastal community livelihood are directly dependent on coastal
wetland resources (Fig. 6.7).
Bangladesh produce with 1 million tons fisheries products, which is more than
twice Indian aquaculture production per capita, Nepal, Pakistan and Sri Lanka, lag
far behind. In the coastal Bangladesh aquaculture is emerging as a prime rural
industry, contributing to employment, food security, poverty reduction and export
earnings. Export of aquaculture products earn Bangladesh half a billion dollars per
year, making them the country’s second-biggest earner of foreign exchange after
textile. All these water resources sectors and sub sectors are inter-connected for
their own sectoral development and management. Therefore coastal water resources
sector is a potential sector in the coastal region and it is playing as a driving force of
sustainable development of the coastal region of Bangladesh.
In most development, water resources management and sustainable livelihood
discourses need for integration at different levels are recognized and emphasized
(Rahman 2003). The soil of the entire coastline is generally sediment deposit of the
GBM and other rivers. Such soils are fertile but recently it has been affected by high
salinity intrusion. It has been estimated almost half of the coastal arable land can be
classified as saline zone, within this saline affected areas such as the greater Khulna
and Patuakhali districts are being the most affected region in the coastal region of
Bangladesh (Jalal 1988).
6 Degraded Coastal Wetland Ecosystems in the Ganges-Brahmaputra Rivers Delta…