Environmental Engineering Reference
In-Depth Information
Table 1.1
Divisions of Indian Sundarbans estuarine system on the basis of salinity
Zone
Areas (blocks) included
High saline (average 24 psu)
Pathar Pratima, Namkhana, Sagar, Kultali, Gosaba and Basanti
Medium saline (average 12 psu)
Canning-I and II, Kakdwip, Mathurapur-II, Jainagar-II
Low saline (average 3 psu)
Kulpi, Mathurapur-I
According to a study conducted by Sengupta
et al. (
2013
), the entire mangrove-dominated
Indian Sundarbans can be divided into hyposa-
line western and eastern sectors and hypersaline
central sector. This spatial variation of salinity is
the outcome of a two decade study in 18 stations
selected in the three sectors of the deltaic com-
plex (Fig.
1.4
). The western sector of the deltaic
lobe receives the snowmelt water of mighty
Himalayan glaciers after being regulated through
several barrages on the way. The central sector
on the other hand is fully deprived from such
supply due to heavy siltation and clogging of the
Bidyadhari channel since the
of the total Sundarbans) and receives the fresh-
water from the River Raimangal and also from
the Padma
Brahmaputra river system
of Bangladesh Sundarbans through several
creeks and inlets. The study revealed that in the
western and eastern sectors, the salinity
decreased by 21.91 and 16.35 %, respectively,
over a period of 24 years, whereas, in the central
sector, there has been a steady increase in the
salinity by 9.32 % during the same period
(Fig.
1.5
).
In recent times, we have analysed the salinity
value of past 30 years in three sectors of Indian
Sundarbans and attempted to forecast the trend of
salinity in the next 30 years. Our analysis is
based on 18 stations (6 in each sector of Indian
Sundarbans) as marked in Fig.
1.6
and Table
1.2
.
Meghna
-
-
fteenth century
(Chaudhuri and Choudhury
1994
). The eastern
sector of Indian Sundarbans is adjacent to the
Bangladesh Sundarbans (which comprises 62 %
Fig. 1.4
Map of Indian Sundarbans showing the locations of sampling stations in the western, central and eastern
sectors.
Source
Sengupta et al. (
2013
)
