Agriculture Reference
In-Depth Information
Fig. 2.11
Field conditions.
a
Sippighat,
b
Bambooflat
images of the area, it is clearly visible that sea water occupied a significant part
of land in 2005 after the tsunami due to subduction of land. Dam Roy and Krish-
nan (
2005
) and Chatterjee et al. (
2008
) also had the same observations. The area
submerged in water further increased in 2007 as can be seen in the satellite image
of 2007. Figure
2.11a
shows the field situation in 2009 (subsequent to the period
of satellite image). It can be seen that the area is still submerged and there is no
improvement. Further deterioration, if any, can be confirmed only after the study of
satellite data of the year 2009 which was not available at the time when the study
was carried out. Figure
2.10
shows the situation in Bambooflat area of South Anda-
man. A marginal decrease in mangrove cover but significant increase in water area
is noticed by comparing images of 2003 and 2005, but there is a significant change
in the land area which is now occupied by the sea water. Considerable loss in man-
groves can be noticed between 2005 and 2007. Field situation in 2009 of mangroves
of this area is depicted in Fig.
2.11b
.
In North Andaman Islands, particularly in Diglipur, impact of these geo-mor-
phological changes on mangrove vegetation has been more pronounced. If satellite
images of January 2003 and February 2005 are compared, there does not appear
to be any significant change in the mangrove cover immediately after the tsunami
(Fig.
2.12
), but images of subsequent period (February 2007) show significant deg-
radation in the mangrove area. Dam Roy and Krishnan (
2005
) also reported that
mangrove stands in many locations were exposed. They observed that even during
high tide, sea water was not reaching the mangrove plants resulting in the onset of
wilting in these plants and their death eventually. Field situation in Shyam Nagar
area of North Andaman in 2009 is shown in Fig.
2.13
. It shows that mangroves in
the area are almost dried up and are dying.
Nicobar Islands have witnessed the maximum damage during the tsunami owing
to their proximity to the epicenter of the massive earthquake of December 26, 2004.
Satellite data-based results of the present study are given in Table
2.2
. There has
been a significant decrease in the mangrove cover in all major islands of Nicobar
district. Total decrease in mangrove cover in Nicobar district between 2003 and
2005 is 1500 ha. Maximum loss of mangrove cover was noticed in Katchal (567 ha)
