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Calculating carbon values
Replicate plots along transects were
assessed for plant cover and sampled for
above-ground biomass and soil carbon
stocks (total, organic and inorganic)
to depths up to 3 metres depending
on the substrate. At intertidal sites,
additional data were collected to inform
a mechanistic understanding of carbon
cycling including water table depth,
pore-water chemistry, root zone redox
potential, and soil respiration. High
resolution location and elevation data
were collected via Kinematic GPS and a
mobile base station.
In the laboratory, above and below-
ground carbon stocks were calculated
through allometric equations. Carbon
and nitrogen analyses were performed
by an elemental analyzer.
Sampling and analysis followed
scientifically recognized standards and
procedures adapted to the Emirate’s
environmental context.
Resulting carbon values
Across the range of ecosystems studied,
algal mats showed the highest combined
above and below ground carbon stocks
per hectare. Overall Blue Carbon stocks
are estimated to be highest in seagrass,
due to the large extent of the ecosystem.
Carbon Values of Blue Carbon Ecosystems
Coastal Sabkha
Seagrass
Mangrove
Saltmarsh
Algal mat
0
25
50
75
100
12.5
Km
Coastal sabkha, which is considered an
associated ecosystem, holds significant
amounts of carbon, highlighting the
importance of well-informed planning
of sabkha conversion.
Average total carbon stock in planted
mangroves of different ages (79,92
tonnes/ha) was lower than that of
natural mangroves (109,79 tonnes/ha).
See figure 7 for details.
Overall, Blue Carbon ecosystems in Abu
Dhabi are calculated to store over an
estimated 41 million tonnes of carbon
dioxide equivalent (CO
2
equivalent)
within the soil and biomass, more than
the Emirate’s annual emissions from
the oil and gas (26,4 million tonnes)
or water and electricity (30,9 million
tonnes) sectors
1
.
Figure 6
Carbon stock sampling locations
1
Statistical Yearbook of
Abu Dhabi 2013
40