What is Blue Carbon?

Blue carbon refers to carbon stored in coastal and marine ecosystems, including wetlands, kelp forests, mangrove forests, seagrass, and coral reefs. Commonly known as blue carbon ecosystems, they sequester and store large quantities of blue carbon in both the plants and the sediment below.

Blue carbon ecosystems are found on every continent except Antarctica. SeaTrees develops coastal restoration projects across five blue carbon ecosystem types: mangrove forests, kelp forests, seagrass meadows, coral reefs, and coastal watersheds.

Mangrove Forests

Mangrove forests are being lost at a rate of 2% per year, and these critical ecosystems are 5x more effective at storing carbon than tropical forests.

Learn More about Mangroves

Kelp Forests

Kelp can sequester ~200 million tons of carbon dioxide per year by absorbing CO2 from both the atmosphere and the ocean and exporting large portion of its biomass out into the deep sea, sinking it to the deep ocean permanently. Each year 10% of kelp primary productivity is permanently sequestered.

Learn More About Kelp Forests

Coral Reefs

Coral reefs are home to 25% of all marine life in the ocean and are the most diverse marine ecosystem on earth. Coral can sequester huge amounts of carbon from dissolved CO as carbonate - so that carbon stays within in the reef system and out of the ocean and atmosphere. 

Learn More About Coral Reefs


Seagrasses are being lost at a rate of 1.5% per year. They cover less than 0.2% of ocean floor, but store about ~10% of the carbon buried in ocean sediment each year.

Learn More About Seagrass



Blue carbon ecosystems are most effective when they are directly connected to a healthy watershed, which can capture and store atmospheric CO2 at 10x the rate of a mature tropical forest by sequestering it in the ground for many years.

Learn More About Watersheds


83% of the global carbon cycle is circulated through the ocean, and coastal ecosystems account for approximately half of the total carbon sequestered in ocean sediments.

340,000 to 980,000 hectares of blue carbon ecosystems are destroyed each year. They are some of the most threatened ecosystems on Earth. The regeneration of these ecosystems provides critical habitat for countless species, sustainable long-term employment for local communities, and protection from climate change impacts.

Blue carbon Ecosystems are 5-10x more efficient at sequestering carbon than any forest on land. Yet when destroyed, these ecosystems emit the carbon they have stored for centuries into the atmosphere and oceans and become sources of greenhouse gases.