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Seaweed
The other noteworthy ecosystem
is macroalgae, often referred to as
seaweed. Macroalgae occur in coastal
zones where there is enough light for
photosynthesis and a firm attachment
point from which they grow. They are an
integral part of many coastal ecosystems
and form one of the bases of food chains.
While macroalgae photosynthesize
and remove carbon dioxide from the
atmosphere, they do not deposit carbon
into sediments. Most excess carbon
is quickly consumed by marine life,
decomposed and recycled or exported
out of the system. The high turnover of
biomass means that carbon storage in
macroalgae is basically limited to the
carbon stored in their biomass, and
carbon is generally not sequestered
into longterm reservoirs (Reed and
Brzezinski, 2009).
Corals
Coral reefs, often associated with Blue
Carbon ecosystems such as seagrass
and mangroves, are some of the most
diverse ecosystems in the world,
harbouring an approximate 25% of
all marine fish species (Spalding
et al,
2001). Abu Dhabi hosts 34 species of
hard coral, providing services that sustain
livelihoods, enhance fish productivity,
protect shorelines from storms and
erosion, offer organisms of medicinal
value and provide employment through
recreational underwater activities. Coral
reefs are mostly found in nutrient-poor
waters with low sediments loads, a
quality to which Blue Carbon ecosystems
such as mangroves contribute.
The current scientific consensus is that
coral reefs are net carbon dioxide emitters
due to the calcification process that results
in their calcium carbonate skeletons
(Laffoley, D.d’A. & Grimsditch, G. 2009).
Corals have an essential role in Abu Dhabi’s coastal
environment, thriving in nutrient-poor waters.
Photo: © AGEDI / Emma Corbett
© AGEDI / Pat Megonigal
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