should be raised along the coastal
areas.
Neglected sand dunes and
associated vegetation
Small sand dunes with various
kinds of vegetation are present all
along the coast. A few of them are
owned by individuals but a majority
of them are common property,
belonging to either the Panchayat
or other government agencies.
However, there is no system in
place for the management of these
coastal sand dunes. Conservation
of these sand dunes with suitable
sand binding and tree vegetation
with the participation of the local
community should be taken up as
a priority issue because these dunes
act as barriers against cyclones and
tsunami and play a dominant role in
water conservation in coastal areas
where water scarcity is a recurrent
feature during the summer season.
to the shoreline. This current
system, in combination with
wind-induced waves, takes
away sand from one place and
deposits it in another area.
Since this process takes place
simultaneously all along the
coast, a balance is achieved
between removal and supply
of sand in a given place and
this balance avoids sea erosion.
If shelterbelt plantations are
raised starting from the high
tide line, than the supply of
sand to the littoral current
would be reduced or stopped
(due to sand binding property
of the plantation) and to
compensate this, current and
waves would remove large
chunk of sand in other areas,
leading to sea erosion in those
areas. In order to avoid such
problem a part of the beach
from high tide line to landward
portion should be left free.
Casuarina shelterbelt and coastal
ecology
Conclusion
Starting of casuarina plantation
right from the high tide line is one
of the serious concerns relating
to shelterbelt plantation along the
coastal areas. This may have serious
implications on the ecology of the
coastal areas and on wildlife.
a) Many of the sandy beaches
are utilized by sea turtles as
nesting grounds and it has been
reported in many places that
raising of casuarina very close
to the sea prevented nesting by
sea turtles.
b) Different species of crabs lives
in different vertical zones near
the high tide line and planting
of casuarina close to high tide
line would affect the niches of
these crabs
c) Most importantly, sandy
beach supplies sand to littoral
current, which run parallel
The role of coastal forests and
man-made plantations in protecting
coastal a r e a s f r o m t s u n a m i
and other natural hazards such
as cyclones, storm surges was
deliberated comprehensively in a
technical workshop by Food and
Agriculture Organization (FAO)
in Bangkok in 2006. The workshop
brought together the best available
knowledge and experience to give
a clear picture of the roles that
forests and trees play in protection
against hydrometeorological and
geophysical hazards in the wider
context of coastal planning and
social, economic and environmental
considerations. It also assessed
the value of coastal vegetation
compared to other commonly
used hard (engineered) structures
for coastal protection. The major
findings in the workshop are:
YOJANA March 2012
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Forests and trees can act as
bioshields that protect people
and other assets against
tsunamis and other coastal
hazards but whether they are
effective and the degree of their
effectiveness depend on many
variables. These variables
include characteristics of the
hazards itself, the features of
the site such as bathymetry,
geomorphology and the
characteristic of the bioshield
such as type of forest/tree,
width, height, density etc.
Care must be taken to avoid
making generalizations
and creating a false sense
of security that bioshields
will alone protect against al