Geoscience Reference
In-Depth Information
Figure 15-2.
Ganges Delta, Sundarbans, India and Bangladesh (see Color Plate 15-2). The protected mangroves are
highlighted in red in this color-infrared photograph. Black line marks the national boundary. STR - Sundarbans
Tiger Reserve, SWWS - Sundarbans West Wildlife Sanctuary, SSWS - Sundarbans South Wildlife Sanctuary, and SEWS
- Sundarbans East Wildlife Sanctuary. Image courtesy of K. Lulla; STS061B-50-007, December 1985.
shapes the land adjacent to the Bay of Bengal
and helps build sand bars, dunes, mudl ats and
islands over time through the accretion of sand
and alluvial material deposited by the rivers
(Gopal and Chauhan 2006). By the same token,
severe storms can wash away islands in a matter
of hours or days, and this constantly shifting
landscape typii es the processes that have
shaped the delta over time.
Cyclonic activity is quite common during the
summer and post-monsoon period. The region
has experienced enormous loss of life and prop-
erty in the past due to severe cyclonic events
that are coupled with devastating tidal surges
followed by widespread l ooding. Table 15-2
provides a look at some of the most devastating
storms experienced by Bangladesh and the
accompanying staggering loss of human life
(Hossain 2001). The vulnerability of this coastal
zone would only become more acute with pre-
dicted sea-level rise, the destruction of protec-
tive mangroves due to development demands,
and persistent conditions of poverty experi-
enced across the region.
Table 15-2.
Cyclonic activity, storm surges, and
approximate loss of human life in Bangladesh for
selected storms. Adapted from Hossain (2001).
Date
Cause
Casualties
May 1822
Cyclone
40,000
Oct. 1876
Cyclone, storm surge
height
400,000
=
14 m
Oct. 1897
Storm surge
175,000
May 1965
Cyclone, storm surge
height
19,270
=
4 m
Nov. 1970
Cyclone, storm surge
height
500,000
=
14 m
April 1991
Cyclone, storm surge
height
150,000
=
6 m
Coastal mangrove ecosystems typically
observe spatially dei ned zones based on the
topography and coni guration of the landscape,
substrate, tidal action, and salinity ranges. Sci-
entists have provided classii cation schemes that
divide mangrove forests based on their occur-
rence along coastlines. Across the eastern coast
of India, coastal mangroves are classii ed into
proximal, middle and distal zones depending on
