What is Blue Carbon?
Blue carbon refers to the carbon captured and stored by oceanic and coastal ecosystems, such as mangroves, seagrass beds, and salt marshes, but in the last five years, ecosystems such as wetlands and peatlands have also been considered. These ecosystems act as highly efficient "carbon sinks," absorbing carbon dioxide (CO₂) from the atmosphere and storing it in their biomass (leaves, roots, trunks) and sediments for thousands of years.
Key features of blue carbon:
High capture capacity:
- Mangroves, for example, can store up to 10 times more carbon per hectare than terrestrial forests.
- Peatlands, in turn, have 50 times more carbon captured in the soil than the Amazon forests.
- The sediments of these ecosystems accumulate carbon in a deep and lasting way.
Main ecosystems:
- Mangroves: Coastal forests in tropical areas.
- Seagrass: Marine plants that form underwater meadows.
- Marshes: Coastal wetlands with salt-tolerant vegetation.
Climatic importance:
- They mitigate climate change by capturing CO₂.
- If they degrade, they release stored carbon, accelerating global warming.
Additional benefits ( co-benefits ):
- Coastal protection: Reduces erosion and cushions storms.
- Biodiversity: They are breeding grounds for fish, mollusks and birds.
- Sustainability: Support local livelihoods (fishing, tourism).
Connection with blue carbon credits:
Conservation or restoration projects in these ecosystems can generate blue carbon credits, which are sold in voluntary markets to finance their protection, improve the quality of life of nearby communities, and generate profits for landowners, creating a virtuous cycle. Each credit is equivalent to 1 ton of CO₂ avoided or captured.
Blue Carbon Credits.
Blue carbon credits are a specific type of carbon credit generated from the protection, restoration, or sustainable management of coastal and marine ecosystems, as well as wetlands and peatlands, which naturally capture and store carbon. These ecosystems are true underwater "carbon sinks . "
What exactly are they?
A blue carbon credit is equivalent to 1 tonne of CO₂eq that has been captured or avoided through the conservation of:
- Mangroves
- Marshes (salt wetlands)
- Seagrass
- Wetlands
- Peat bogs.
How are they calculated?
- Carbon stored in biomass (trees, roots, plants).
- Carbon buried in sediments (up to 1 meter deep)
- Carbon avoided ( e.g. avoiding mangrove deforestation).
- Emission factors due to ecosystem degradation or loss.
Projects that generate them:
- Mangrove reforestation.
- Protection of coastal areas from destructive logging, urbanization, or aquaculture.
- Restoration of seagrass or marshland.
- Sustainable community management of coastal resources.
- Conservation of wetlands and peatlands.
Duration of a project.
- Long term (30-50 years), making them very attractive for long-term purchase by international investment funds.
- They require continuous monitoring ( e.g. , measurement of sediments, biomass).
Why are they important?
High efficiency: They capture up to 10 times more carbon than terrestrial forests and their carbon sinks contain up to 50 times more carbon than forests.
Key co-benefits :
• Coastal protection against storms and erosion.
• Habitat for marine species (fish, crustaceans).
• Sustainable fishing and tourism.
• Compliance with SDGs ( e.g. SDG 14 - Life below water).
• Freshwater filters and distributors.
• They are true incubators of all kinds of flora and fauna species.
Challenges:
• Complex methodologies (underwater measurement).
• Climate change risks (sea level rise).
• Tenure rights in coastal areas (local communities).