A seaweed meadow to fight global warming

The world’s largest seaweed meadow could help combat climate change.

Restoring underwater meadows

Seagrass beds now cover only 0.2% of the seabed, while their capacity to absorb carbon is 35 times greater than that of tropical forests, according to WWF. An overall decrease is caused by human activity that alters water quality and destroys natural habitats. In Virginia, as a result, there have been no seagrasses since 1930.

An algae restoration project was therefore set up in southeast Virginia. In 2000, scientists from the Virginia Institute of Marine Sciences and volunteers from The Nature Conservancy scattered more than 70 million grass seeds over 200 hectares. For 20 years, researchers observed their evolution and extension over 3,600 hectares. Their analyses now make it possible to understand the restoration of seagrass meadows and their impact on the environment.

Équilibrer l’écosystème

This restoration has highlighted the surprising resilience of the ecosystem, which is helping to counter global warming. This is because seagrass beds trap nitrogen and carbon, two main greenhouse gases. In 20 years, the grasslands have then sequestered 600 tons of nitrogen, and 3000 tons of CO2 which are equivalent to the emissions of 653 cars for one year! Their resistance is all the more beneficial as the capacity to trap these gases increases with the maturity of the algae; thus mature meadows absorb 2.2 times more nitrogen and 1.3 times more carbon than young ones. Reconstructing these seagrass beds also has benefits for marine biodiversity. Because they provide a refuge for the animals that store their food and keep their children there, they also prevent erosion of the seabed.

This project, therefore, embodies “an example of how nature-based solutions can help mitigate climate change,” for Carlos Duarte, a marine ecologist in Saudi Arabia. That’s why scientists are considering replicating it in other regions of the world, such as Biscayne Bay in Florida.

Sources: WWF; Good News Network; Planet Vie

Photo Credits :@boardshortsben/Unsplash;@tbep/Unsplash

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