Rob Barnes/AGEDI/Blue Forests

Planting mangroves as part of a blue carbon project on the Persian Gulf.

Coastal Wetland Restoration

CO2 Equivalent
Reduced / Sequestered
Agriculture, development, and natural disasters have degraded many coastal wetlands. Restoring mangrove forests, salt marshes, and seagrass beds to health revives carbon sequestration.

Solution Summary*

Along the fringes of coasts, where land and ocean meet, lie the world’s salt marshes, mangroves, and sea grasses. These coastal wetland ecosystems are found on every continent except Antarctica.

They provide nurseries for fish, feeding grounds for migratory birds, a first line of defense against storm surges and floodwaters, and natural filtration systems that boost water quality and recharge aquifers. Relative to their land area, they also sequester huge amounts of carbon in plants aboveground and in roots and soils below.

Coastal wetlands can store five times as much carbon as tropical forests over the long term, mostly in deep wetland soils. The soil of mangrove forests alone may hold the equivalent of more than two years of global emissions—22 billion tons of carbon, much of which would escape if these ecosystems were lost.

Wetlands face a myriad of threats, but thanks to research and advocacy efforts, awareness is growing about the role they play in curbing climate change and coping with its impacts. It is vital to preserve healthy coastal wetlands—keeping a lid on the carbon they contain—while also rehabilitating and restoring those that already have been degraded. 

* excerpted from the book, Drawdown

Like forest and peatlands, the coastal wetlands are subjected to severe degree of degradation. Restoring mangroves, salt marshes, and seagrasses are critical as a solution to global warming as well as restoring biodiversity and ecosystem services provided by these. Protecting 6.1–7.2 million hectares of currently degraded coastal wetlands by 2050 and allowing natural regrowth to occur sequesters 0.99–1.01 gigatons of carbon dioxide by 2050.

Note: August 2021 corrections appear in boldface.