Environmental Engineering Reference
In-Depth Information
Table 3.4
(continued)
Threats
Description
Conservation
5. Pollution
The Gautami-Godavari mangrove estuarine
ecosystem is severely polluted in terms of
heavy metals. The region is signi
cantly
polluted with heavy metals such as Zn, Cu,
Mn, Fe, Co, Ni and Cr. It is also reported that
some of the main industries discharge their
effluents directly into the aquatic system
(about 6500 kL/day) which ultimately reach
the Coringa River
Awareness generation programme involving
the industrialists,
shermen, Forest
Department staffs, pollution control
authorities and other stakeholders may be
arranged on regular basis to ensure the
treatment of effluents before their discharge
from the point sources. Also, high-end
researches should be initiated to monitor the
role of mangrove flora and other associated
species in the process of bioremediation
6. Biodiversity
loss
In Coringa mangrove ecosystem, fteen
species of true mangroves (dominant species
are
Loss of biodiversity can be prevented only by
the awareness of the local people and by
providing alternative livelihood be
tted with
the local environment and situation. A very
interesting research in this context has been
published by Pramanick et al. (
2014
)in
which the researchers prepared edible
products from fruits of
Avicennia marina, A. of
cinalis,
Exoecaria agallocha, Sonneratia apetala,
Aegiceros corniculatum
and
Rhizophora
apiculata
) and six mangrove associate
species are very common (Checklist of
Coringa mangroves
Vide
Annexure).
S.
Sonneratia apetala
(Fig.
3.10
), which is not only nutritionally
balanced, but also can serve as a unique
source of livelihood for the villagers of
mangrove fringe zones
casualaris
is reported to be at the verge of
extinction and A. marina is the most
abundant in the region because of its wide
range of salinity tolerance
Molluscan shell burning is common in the
area, and it is reported that about
3,600 tonnes of molluscs are removed
annually from Kakinada Bay and Coringa
mud
fl
ats for lime production
7. Wild harvest of
tiger prawn seeds
Collection of post-larval stage of Penaeus
monodon is done to feed the shrimp farms
in and around the Coringa mangrove
ecosystem. During this collection, a variety
of juveniles of other species are caught in the
net and destroyed as they are non-
remunerative to the seed collectors
Development of shrimp hatcheries at
subsidized cost (through Government
intervention), awareness to the seed
collectors on regular basis and providing
alternative livelihood to the tiger prawn seed
collectors are some of the possible measures
for conservation of
sh juveniles that are
destroyed during the process of collection
and segregation of tiger prawn seeds
8. Grazing
Mangrove
ora particularly the seedlings are
grazed by cows, buffaloes, etc., due to which
trees do not attain their maturity. It is
reported that in Coringa village, about 2,500
cattle graze on the peripheral areas of the
mangroves
fl
Local-level awareness particularly involving
the
shermen communities may yield good
results
It is noted from this table that during the time
span between 1988 and 1998, a signi
clearly show that out of 13,359 ha of mangrove
area, an area of 11,567 ha remained unchanged
during the span of 10 years. This may be attrib-
uted to dense mangrove vegetative cover with
minimum anthropogenic pressure. Changes have
occurred in the areas as conversion of mangroves
to other categories and vice versa. An area of
1,065 ha of mangrove has changed to other cat-
egories such as aquaculture, degraded area and
mud
cant
reduction in mangrove cover is observed within
the Coringa Reserve Forest area. This is con
rmed
with the subsequent increase in degraded areas and
aquaculture areas (Table
3.5
). Using the overlay
facilities of GIS, analysis of 1988 and 1998 land-
use/land cover maps was performed (Fig.
3.13
).
The changes that have occurred in the whole
area are highlighted in Table
3.6
. The results
fl
at. In some pockets, the mangroves have
