The Abu Dhabi Blue Carbon Demonstration Project

Ecosystems of Interest

The Blue Carbon: First level exploration of natural coastal carbon in the Arabian Peninsula - Rapid Feasibility Study , 2011, the predecessor to the Abu Dhabi Blue Carbon Demonstration Project, identified costal sabkha as expressing characteristics with the potential to sequester and store carbon. As a result, it was assessed as a candidate Blue Carbon ecosystem within the subsequent project. Through the surveys of the project however, coastal sabkha was found to not sequester carbon, but potentially to cap buried carbon, and therefore can be considered as a Blue Carbon associated ecosystem. Algal mats (also known as cyanobacterial mats or microbial mats) can have close associations with coastal sabkha. They were found to flourish in sheltered coastal arid zone environments where vascular plants are excluded by very high soil salinities. This close relationship with coastal sabkha also prompted the hypothesis that these algal mats may have the potential to sequester and store carbon. The algal mats were therefore considered as a candidate Blue Carbon ecosystems during the assessments.

As carbon dioxide is likely to be released when areas are degraded to accommodate mangrove plantings, these should be carefully planned on a scientific basis to avoid unintended consequences. It is therefore recommended that geomorphology, connections to other marine and coastal ecosystems and the ability of mangroves to adapt to climate change- driven environmental impacts should be central considerations in future afforestation projects.

Figure 3 Illustrates the relationship between the Blue Carbon ecosystems in Abu Dhabi, the history of a shoreline shifting seaward and resulting the soil profiles. The presence of these buried former Blue Carbon ecosystems within profiles encountered has relevant implications for future development in these areas.

Subtidal Zone

Intertidal Zone

Supratidal Zone

Mangrove

Coastal Sabkha

Salt Marsh

Mean Tide Level

Buried Algal Mat Mangrove Paleosoil

Marine Sands

Buried Seagrass

Lateral Accretion

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