Térraba-Sierpe National Wetland
The potential of wetlands and coastal ecosystems to sequester atmospheric carbon and serve as tools for climate change mitigation has not been systematically quantified in Central America. With a financial contribution from GIZ’s BIOMARCC Project (Coastal Marine Biodiversity and Climate Change Adapatation Project), this project provided the first-ever estimates of ecosystem carbon stocks for Central America.
Dr. Miguel Cifuentes, a scientist from CATIE (The Tropical Agricultural Research and Higher Education Center), and his team worked at the Térraba-Sierpe National Wetland, a RAMSAR site located in southern Costa Rica, approximately 270 kilometers from the capital city San José. A total of 28 sampling sites were established in the mangrove forests of Térraba-Sierpe. Standard methods were used to establish a series of circular nested plots and measure biomass and carbon stocks in all ecosystem components (standing trees, regeneration, herbaceous layer, litter, downed wood, and soils to 1 m in depth).
Mean aboveground carbon stocks reached 72.5 ± 3.2 MgC·ha-1 (range: 9 - 241 MgC·ha-1), consistent with stocks measured in other locations around the world. Between 74 and 92% of all aboveground carbon is contained in trees ≥ 5cm dbh. We found a strong correlation between the basal area of these trees and the total aboveground biomass of these mangrove forests. Once validated, this equation may simplify the estimation of aboveground carbon stocks in tropical mangrove forests. Total soil carbon stocks to 1 m depth ranged between 141 and 593 MgC·ha-1. Total ecosystem carbon stocks range between 391 and 438 MgC·ha-1.
Using these data, we calculated mangrove forests growing in the Terraba-Sierpe National Wetland have sequestered close to 8 teragrams of carbon, approximately 40% of all carbon stored in Costa Rican mangroves. Considering the land use patterns in the area, we estimated a historic loss of close to 4000 hectares of mangroves in the area between 1990 and 2012. The associated loss of carbon is equivalent to almost 70% of all country-wide CO2 emissions reported in the 2005 national greenhouse gases (GHG) inventory. These amounts are thus significant and, worryingly, have not been included in national-scale carbon accounting.
Lessons learned from this project are providing much needed information for Costa Rican authorities and GIZ to support the development of blue carbon policy and financial mechanisms for the Terraba-Sierpe National Wetland. CATIE is also seeking for partners and funding to expand its blue carbon research and implementation goals to other Central American countries.
For additional information, please contact:
Miguel Cifuentes Jara, Ph.D.
Climate Change & Watersheds Program
Cartago, Turrialba 30501
+(506) 2558-2510 or 2558-2393
About the BIOMARCC Project:
The BIOMARCC Project (Biodiversidad Marino Costera y Adaptación al Cambio Climático) strengthens the Costa Rican National System of Conservation Areas (SINAC/MINAET). It is implemented by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU), and its International Climate Initiative (IKI).
The Tropical Agricultural Research and Higher Education Center (CATIE) is a regional center dedicated to research and graduate education in agriculture, and the management, conservation and sustainable use of natural resources. Its members include the Inter-American Institute for Cooperation on Agriculture (IICA), Belize, Bolivia, Colombia, Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Venezuela, Spain and the State of Acre in Brazil.