Desert mangroves might store a lot more carbon than researchers once thought. Scientists have taken a closer look at mangroves and have found they play a huge role when it comes to keeping carbon under wraps.

Currently, mangroves are removed each year due to human activities. In fact, scientists estimate that mangrove forests are decreasing by 3 percent per year. This removal of mangroves can result in the release of carbon.

In this latest study, the researchers collected sediment core samples from below mangrove roots at two desert lagoons and two tropical lagoons. Then, the scientists calculated the carbon stored at the four locations.

The researchers found that the cores represented a 2,000-year-old layer of non-decomposed roots that was up to 13 feet beneath the desert mangroves. The peat acts as a type of sponge for atmospheric carbon, storing it there for a long time.

"Mangroves represent a thin layer between ocean and land, and yet we are seeing an ecosystem that is storing a lot of carbon in a very small area," said Paula Ezcurra, the lead author of the new study.

The researchers found that the desert mangroves around the coast of Baja California have been growing over their own root remains for thousands of years. This helps the mangroves compensate for sea level changes by slowly building up "ground" beneath them.

"The results show how these ecosystems have been adapting to climate change and sea-level rise for thousands of years," said Octavio Aburto Oropeza from the Scripps Center for Marine Biodiversity and Conservation. "Understanding the link between the natural history and carbon storage capacity of mangrove environments could give use insight into future climate change and sea-level rise."

The findings are important when it comes to better understanding these mangroves and their place in natural ecosystems.

"Our study helps to further quantify the value of mangrove forest ecosystems, and highlights the importance of mangrove conservation," said Exequiel Ezcurra, one of the researchers. "Hopefully it will serve to underscore the urgent need for mangrove protection and for the serious appraisal of the environmental services provided by common-access resources."

The findings are published in the March 2016 journal Proceedings of the National Academy of Sciences.