Blue carbon in the mangrove forests of Colombia

In the Colombian archipelago of San Andrés, Providencia, and Santa Catalina, blue carbon stock (aboveground biomass, aboveground dead biomass, and soils) of the mangrove ecosystem is being evaluated by INVEMAR and the Corporation for the Sustainable Development of the Archipelago of San Andrés, Providencia and Santa Catalina (CORALINA).

Samples were collected in 34 circular plots of 452 m², and analyses were carried out according to the physiographic type of the mangrove forest (inland, fringe and basin forests).

On the island of San Andres, 22 plots were located; 13 of these corresponded to inland mangroves, 6 to fringe mangroves, and 3 to basin mangroves; whereas on the island of Providencia and Santa Catalina, 12 plots were located; 7 fringe mangroves and five basin mangroves.

Currently, the results of total organic carbon in soils are in the analysis process but initial analysis of aboveground biomass shows the highest value of organic carbon content was recorded in the mangroves in San Andres (154.2 ± 36.8, 72.7 ± 8.0, and 70.7 ± 10.7 Mg C/ha for inland, fringe, and basin mangroves, respectively).

Due to the impact of hurricanes Eta and Iota during October 2021, results from Providencia indicate the highest value of carbon content was recorded in aboveground dead biomass (76.0 ± 23.0 and 75.7 ± 27. 9 Mg C/ha for basin and fringe mangroves, respectively). The hurricanes severely impacted mangrove tree structure and caused the death and fall of more than 90% of mangrove trees. Thankfully, the island of San Andres was less impacted by the storms and aboveground dead biomass contributed less to the total aboveground carbon (27. 1 ± 13.1, 22.5 ± 9.2 and 18.2 ± 11.2 Mg C/ha for inland, fringe and basin mangroves, respectively).