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It is uncertain what would have been the sit-
uation in Banda Aceh if the mangroves had not
been destroyed. However,
Thampanya 2007 ). A more proper test of the
same data indicated no signi
cant effect of the
presence or absence of mangroves on the human
death toll (Kerr et al. 2006 ) and points to the
need for caution to avoid overstating the role of
mangroves in tsunami protection. Nevertheless,
ground surveys and QuickBird pre-tsunami and
IKONOS post-tsunami image analysis (Daniel-
sen et al. 2005 ) and multivariate analysis of
mangrove
ve villages 100 km
to the southeast of the city were saved by the
extensive mangroves in that area (Parish 2005 ).
Also, it has been claimed that Simeulue Island,
which is only 41 km from the epicentre of the
earthquake, was saved partly by its substantial
mangrove cover, coral reefs and seagrass beds
and suffered only four deaths in the disaster as a
result (IUCN 2005 ; Parish 2005 ). Reports from
eyewitnesses on Simeulue Island state that no
wave penetrated the mangrove forests, and
instead the water level increased gently
eld data (Dahdouh-Guebas et al.
2005 ) covering the entire Tamil Nadu coast
suggest less destruction of man-made structures
located directly behind the most
extensive
'
like a
mangroves.
F.2. Nargis and Blue Carbon
The blue carbon community has been adversely
affected by Nargis. Cyclone Nargis struck
Myanmar on 2 and 3 May 2008, making landfall
in Ayeyarwady Division, approximately 250 km
southwest of Yangon. A category 3 cyclone,
Nargis, affected more than 50 townships, mainly
in Yangon and Ayeyarwady Divisions, including
Yangon, the country ' s largest city. Strong winds
and heavy rain caused the greatest damage in the
Ayeyarwady Delta, where a storm surge com-
pounded the impact of the cyclone. Nargis was
the worst natural disaster in the history of
Myanmar. More than 140,000 people were kil-
led, mainly by the storm surge. The loss and
damage of mangrove forests as a result of Nargis
is particularly critical (Fig. 7.10 ), which affected
about 16,800 ha (41,514 acres) of natural forest
and 21,000 ha (51,892 acres) of forest plantations
(PONJA Report 2008 ). Surveys by Maung
( 2008 ) indicated signi
rising tide
(Parish 2005 ).
However, in the area of Ulee Lhee, close to
Banda Aceh, not even dense, healthy mangroves
were capable of withstanding the tsunami, such
was the force of the wave (Wetlands Interna-
tional
'
Indonesia Programme 2005 ). Prior to the
tsunami, there was 10 ha of relatively healthy
mangroves at the site but the tsunami did not
leave a single tree standing they were all
uprooted and carried inland by the waves and
were found in residential areas up to two or three
kilometres away (Wetlands International
Indo-
nesia Programme 2005 ).
Mangrove forests impacted by the 2004
Indian Ocean tsunami were mostly located in
sheltered areas (bays, lagoons and estuaries) with
very few located on open coast, making it ini-
tially dif
cult to assess whether the areas
impacted by the tsunami suffered less because of
the intrinsic protective capacity of the forests, or
because they were sheltered from direct exposure
to the open sea (Chatenoux and Peduzzi 2007 ).
However, several reports based on initial post-
impact surveys in south-eastern India, the And-
aman Islands and Sri Lanka (Danielsen et al.
2005 ; Dahdouh-Guebas et al. 2005 ; Kathiresan
and Rajendran 2005 ) indicated that mangroves
offered a signi
cant destruction of man-
groves in the direct path of the cyclone and in
adjacent areas. Defoliation and damage to bran-
ches ranged from 38.9 to 55.6 % and damage to
crowns was between 12.8 and 19.8 % (Fig. 7.10 ).
Uprooting of trees was notably higher in the
direct path of the storm (56.7 %) than elsewhere
(4.2 %).
F.3. AILA and Blue Carbon
The incidence of AILA (a severe tropical
cyclonic storm) in the Gangetic plain region of
India on 25 May 2009, (Fig. 7.11 ) posed severe
impacts in terms of embankment damage in areas
not protected by mangroves.
cant defence against the full
impact of the tsunami. The conclusions of Ka-
thiresan and Rajendran ( 2005 ) and Vermaat and
Thanpanya ( 2006 ) that the presence of man-
groves saved lives along the Tamil Nadu coast of
south-east India are invalid, however, as inap-
propriate statistical tests were used (Vermaat and
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