Environmental Engineering Reference
In-Depth Information
7.3
Case Studies on Blue Carbon
Loss
Salt marsh also contributes a very important
component of blue carbon community. Several
causes have been identi
ed from the loss of this
community, which include submerges by sea
level rise, erosion, draught, warming, grazing
and fungal infection (Flory and Alber
2002
;
Alber et al.
2008
). Another cause of salt marsh
loss is due to invasive reed expansion. The
invasive growth usually occurs along the upper
edges of salt marshes and gradually extends
towards the sea. The invasive taxon appears to be
more tolerant to salinity (Vazquez et al.
2006
)
grows better in response to genotype (Packett
and Chambers
2006
) and seems to be favoured
by the urbanization of the adjoining water sheds
(King et al.
2007
).
The environment of the planet Earth is under-
going remarkable changes and the rate of such
changes is increasing particularly due to
unplanned human activities. The root cause lays
basically on the unprecedented rise in human
population through the twentieth century
(7,237,115,621; Indian Standard Time 2:23 PM,
dated 01.06.2014) from 1.5 to 6 billion people
in 2000. By 2050, there will be another 30 %
increase in human population. This will increase
the demands for energy, food, water, space and
other resources, which will create several social,
economic and political complications that will
lead to deterioration of the environment. It is
interesting to note, in this context, that major
cities of the World have developed very near to
the coast. The land
is a
common reed and is highly invasive with wide
range of tolerance to salinity.
Nutrient enrichment is also a major driver of
salt marsh loss. We conducted a study dur-
ing 2013 on the impact of nitrate and phosphate
concentrations on the aboveground biomass
(AGB) of P. coarctata in the three sectors of
Indian Sundarbans with variable nutrient con-
centration and observed signi
Phragmites australis
sea interface that supports
the blue carbon reservoir such as mangroves and
salt marshes is under the clutch of intense
industrialization and urbanization. In addition to
this, factors like sea level rise is also considered
as a major threat to blue carbon community
(Nicholls et al.
1999
). Observed through mod-
elling approaches that
-
cant adverse
impact of nutrient enrichment on the AGB of the
salt marsh grass (Tables
7.12
,
7.13
and
7.14
).
The results are in alignment with works of De-
egan et al. (
2012
) who observed that the recent
trend of nutrient enrichment has exceeded the
capacity of salt marsh to remove nutrient from
the ambient media. The nutrient enrichment in
the present time may be attributed to the
increased use of
there will be a loss of
13
20 %
would probably due to sea level rise. More
recently, (IPCC
2007
) published that a
31 % of coastal wetland of which 0
-
-
gure
around 30 % loss of coastal wetlands worldwide.
Data from Valiela et al. (
2001
) reveal a sub-
stantial loss of mangroves in different continents
of the world (Table
7.11
).
fertilizer, urbanization, and
Table 7.11
Current mangrove swamp area, per cent loss, annual loss rate and per cent of original area lost per year, for
the mangroves of the continents and the world
Continent
Current mangrove
area (km
2
)
% loss of mangrove
forest area
Annual rate of loss
(km
2
/year)
% loss of original area
loss/year
Asia
77,169
36
628
1.52
Africa
36,529
32
274
1.25
Australia
10,287
14
231
1.99
America
43,161
38
2,251
3.62
World
166,876
35
2,834
2.07
Source Valiela et al. (
2001
)
