Coastal Carbon Powerhouses

How mangroves, salt marshes, and seagrasses sequester carbon faster than rainforests

The Ocean's Hidden Carbon Vaults

Blue carbon ecosystems—mangroves, salt marshes, and seagrass meadows—cover less than 2% of the ocean floor yet account for 50% of carbon buried in marine sediments.

Unlike terrestrial forests where carbon cycles rapidly through decomposition, coastal wetlands trap organic matter in waterlogged, oxygen-poor sediments. Decomposition slows to a crawl. Carbon accumulates for centuries.

Per hectare, these ecosystems sequester carbon 5-10× faster than tropical rainforests. A single hectare of restored mangrove can remove 6.5 tons of CO₂ annually while providing storm protection, nursery habitat for fisheries, and water filtration.

🌳 Terrestrial Forests

  • 0.5-2 t CO₂/ha/yr sequestration
  • Carbon mostly in aboveground biomass
  • Rapid decomposition releases CO₂
  • Vulnerable to fire and logging

🌊 Blue Carbon Ecosystems

  • 3.7-6.5 t CO₂/ha/yr sequestration
  • 90% of carbon stored in sediments
  • Anoxic conditions preserve carbon
  • Storage duration: 1,000+ years

Interactive Coastal Ecosystem Explorer

Select an ecosystem and explore its layers from surface to sediment

6.5 t CO₂/ha/yr
Sequestration Rate
13.8 M ha
Global Coverage
1-10 m roots
Typical Depth
🌴🌴🌴

Surface Layer

Dense canopy with aerial roots creating protective coastal barriers

Key Features:
  • Tidal flooding tolerance
  • Salt filtration through roots
  • Nursery habitat for fish

💡 Why "Blue" Carbon? These coastal ecosystems sequester carbon in waterlogged sediments where decomposition is 10-50× slower than on land due to anoxic (low oxygen) conditions. This creates long-term carbon storage spanning centuries to millennia.

49 M ha
Total blue carbon area globally
1-7%/yr
Annual loss rate from development
1.0 Gt CO₂
Released annually from degradation