Mangrove forests with a greater variety of plant and animal species store more carbon than more biologically homogenous mangrove forests, according to a new study.
The new research, published Thursday in the journal Functional Ecology, suggests more diverse mangrove forests are healthier mangrove forests, yielding larger quantities of biomass.
The survey of mangroves on Hainan Island, China, also revealed greater levels of soil carbon storage in more diverse mangrove forests.
Over the last few decades, dozens of studies have established strong links between biodiversity and forest health, but the latest paper is the first to explore the connection in mangrove forests.
Though the survey was carried out on a single Chinese island, researchers suggest their findings are likely applicable to mangrove ecosystems all over the world.
For the survey, scientists recorded the abundance of trees, shrubs and other woody plant species in research plots along the entire coast of Hainan Island, in addition to noting the diversity of animal species found in the different plots.
Data on carbon concentrations for each species, as well as soil samples, allowed researchers to estimate the amount of carbon stored in the different lots.
On the eastern side of Hainan Island, researchers measured higher levels of biodiversity and biomass. According to the analysis, the island's eastern mangroves housed more than 1,300 tons of carbon per acre.
Across the rest of the island, mangroves stored an average of less than 800 tons of carbon per acre.
Of course, biodiversity isn't randomly distributed. Researchers found mangrove forests with greater concentrations of soil nitrogen and annual rainfall totals were more likely to host more biomass and greater levels of biodiversity.
"Our findings suggest that mangrove forests with greater diversity also have higher carbon storage capacities and conservation potential," study co-author Guanghui Lin said in a press release.
"Thus, mangrove biodiversity conservation is crucial for ensuring mangrove forests are able to mitigate climate change. We can increase mangrove diversity through restoration and conservation projects, especially those that promote local native species," said Lin, a professor of ecology at Tsinghua University in Beijing.
Researchers hope their findings will encourage policy makers, wildlife managers and others to prioritize the protection of the most diverse mangrove forests.
"Worldwide, particularly in developing countries such as China, mangroves have been lost or degraded over the last several decades," said study co-author Xiaoshan Zhu.
"Restoration of mangrove forests and their habitats are urgently needed not only for preservation of biodiversity but also to increase carbon storage potentials," said Zhu, also an ecology professor at Tsinghua.
In addition to boosting carbon storage, research has shown that healthier, more diverse mangrove forests are better able to adapt to climate change, filter contaminants from the water and protect coastlines from flooding and extreme weather.
One recent survey found that without mangroves, flood damages would climb by $65 billion per year, and 15 million more people would be impacted by coastal floods.
