Who would think that the mud that forms in the mangroves could join the fight against climate change?
Miguel Cifuentes, a researcher of the Tropical Agricultural Research and Higher Education Center (CATIE), knew it, when he received the first results of the study conducted in the mangrove of Térraba-Sierpe Wetland, located in Osa.
“The land represents 76% of total ecosystem carbon, while the trees represent 20%,” explained Cifuentes after seeing that, while the carbon accumulated on the ground reached between 73 and 75 tonnes per hectare, one meter below surface 300 tons could accumulate.
This was one of the conclusions of the investigation by Cifuentes in the framework of the “coastal and marine biodiversity in Costa Rica, capacity building and adaptation to climate change (Biomarcc)” funded by GIZ in support of the National System of Areas conservation (Sinac).
His goal was to quantify how “blue carbon”-capturing the marine and coastal ecosystems-owned mangrove.
“Mangroves are coastal marine ecosystems with high rates of carbon accumulation and a different dynamic. A forest land has a maximum accumulation, but these environments can maintain those rates for many years because the carbon is accumulated in the sediment, “Cifuentes said.
The team led by Cifuentes sampled 28 sites along the river mouths of Térraba, Zacate, Guarumal and Sierpe.
Therefore, it was a stretch of 150 meters from the shoreline, which measure different components of the ecosystem.
He took, information as tree diameter, percentage of regeneration, amount of dead wood and litter and soil samples.
On average, calculated between 391 and 438 tonnes of carbon per hectare in the four mouths. Compared to land, mangroves have much carbon as cloud forests that the country has.
For Cifuentes, the key is in the ecosystem, specifically the relationship between the sediment, roots and tides.
“Part of the dynamics that exist in the coastal marine interface is that exists a flux and reflux of the tides, and a mix of fresh and salt water. So for that dynamic in entering and leaving the water, there is internal cycles where there is a higher sediment deposition. If there were not mangrove, that sediment would be lost because there is no fixed roots organic matter, “said the researcher.
In the future, Cifuentes intends to study the Gulf of Nicoya, to quantify the environmental services provided by mangroves and add them to a payment scheme that helps local development.