Mangroves and Climate Change

Mangrove forest canopy near Jones Lagoon.

NPS image by Matt Johnson

Mangrove forests are incredibly productive ecosystems. A single acre of mangroves can drop two to three tons of leaves per year!

Like other plants, mangroves take carbon dioxide from the air as they photosynthesize. They use this carbon dioxide to produce more leaves. As a result, this carbon gets locked in the leaves instead of the air. This is why plant communities like forests and grasslands are called “carbon sinks.”

Researchers at the South Florida Natural Resource Center for the National Park Service, found that mangrove forests have two to three times the net carbon trapping ability of many other forests, making them an important player in the fight against climate change.

As leaves fall from trees, they decompose and the trapped carbon slowly drains back into the atmosphere. Mangrove leaves drop into the water. Lower oxygen levels in that water means that leaves decay more slowly than they would in air. The leaves also serve as a primary food source for a variety of animals like worms, shrimp, fish and crabs. These animals transport that carbon to deeper water. Deeper still if they are eaten by larger animals. When they die, they sink to the bottom where their carbon remains trapped indefinitely.