Down in Brazil there’s a city in that is increasing the size of their local mangrove forest to protect itself against raising seas and more intense storms. Mangrove forests are excellent at buffering against storms due to their root systems (and that trees in general are good at slowing storms) and how they start beyond the shore line which reduces coastal erosion. The Greater Florianópolis of Brazil’s program to expand their mangroves is improving the local environment while also helping the city’s coastal economy, it;s a win-win.
As a bonus, mangroves are really good at capturing carbon and putting it in the soil so everyone on earth benefits when Brazilians increase their mangroves.
Master’s students are currently comparing the potential for carbon sequestration and storage in natural mangroves and those growing in the landfills of the Greater Florianópolis area. To do this, they’ve collected soil samples from four mangrove areas: two natural ones and two from the artificially created landfills.
The study aims to find out whether mangroves in the latter, human-generated ecosystem have the same carbon-absorbing capacity as natural ones. “Mangrove soil has a high carbon storage capacity, which is why we chose to focus our main analysis on soil rather than roots and leaves,” says Aline Zanetti, a master’s student working on the project.
Mangroves accumulate 50-90% of their carbon in the soil. The waterlogged soil gives rise to a low-oxygen environment, which means that the organic matter that piles up here — leaves, branches, dead animals — don’t decompose as quickly as they would in the open air, thus keeping the carbon they hold in the soil for longer. It’s this waterlogged property that makes coastal ecosystems much more effective carbon sinks than terrestrial forests. For their study, the researchers will also collect samples of mangrove roots to see if there’s a difference in the carbon stock potential of created and natural mangrove roots.