The Abu Dhabi Blue Carbon Demonstration Project

Corals have an essential role in Abu Dhabi’s coastal environment, thriving in nutrient-poor waters.

Photo: © AGEDI / Emma Corbett

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).

© AGEDI / Pat Megonigal

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