Fig Trees Transform Atmospheric CO₂ into Stone, Study Shows

The truth that scientists have recently found is about these nature miracles will really shock you! By doing that, they recycle existing calcium into their hard structure, literally turning part of their own bodies into stone. This transformational research unfolded in Samburu County, Kenya. It’s a great example of how urban forests can combat climate…

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Fig Trees Transform Atmospheric CO₂ into Stone, Study Shows

The truth that scientists have recently found is about these nature miracles will really shock you! By doing that, they recycle existing calcium into their hard structure, literally turning part of their own bodies into stone. This transformational research unfolded in Samburu County, Kenya. It’s a great example of how urban forests can combat climate change through enhanced carbon capture processes while increasing the alkalinity of the soil. We subsequently shared our results at the highly competitive, world-leading Goldschmidt conference in Prague. This work was the combined effort of a collaborative team of Kenyan, American, Austrian, and Swiss scientists.

The research focused on three fig tree species indigenous to Kenya. These trees passively absorb CO₂ from the atmosphere and turn it into calcium carbonate crystalline ‘rocks’ deposited in the soil that surrounds their roots. Of all the species studied, Ficus wakefieldii proved to be the best at sequestering CO₂ in the form of calcium carbonate. This study more generally illustrates the importance of agroforestry practices. It focuses on prioritizing tree species that offer additional environmental returns on investment.

The Role of Fig Trees in Carbon Sequestration

Fig trees provide an abundance of fruits, besides ones that are tasty and sweet. They are essential to our efforts to fight climate change by removing CO₂ from the atmosphere. Over the course of their long lifespan, these trees can sequester over one ton of calcium carbonate into the soil profile over defense. Their photosynthetic pathway is an active oxalate-carbonate pathway, one of three other active pathways of photosynthetic CO2 acquisition. This route was originally discovered in the Iroko tree, Milicia excelsa. The finding that fig trees uniquely possess this ability is a huge step towards understanding the ecological importance of figs.

Dr. Mike Rowley, a senior lecturer at the University of Zurich (UZH), emphasized the importance of recognizing the oxalate-carbonate pathway’s potential for carbon sequestration. He stated,

“We’ve known about the oxalate carbonate pathway for some time, but its potential for sequestering carbon hasn’t been fully considered. If we’re planting trees for agroforestry and their ability to store CO2 as organic carbon while producing food, we could choose trees that provide an additional benefit by sequestering inorganic carbon also, in the form of calcium carbonate.”

The high pH of soil around fig trees is a direct consequence of this process. As the calcium carbonate precipitates out, it changes the soil’s chemical environment, paving the way for other plants and microorganisms to thrive.

Research Methodology and Findings

In this taxonomically and morphologically complex group, the research team used a standardized methodology to study the three fig tree species in their native habitat. From there, they characterized the carbon sequestration potential of each species. Then, they measured how well each one converted atmospheric CO₂ into calcium carbonate. These new findings indicate that Ficus wakefieldii is unique among its relatives in this greater efficiency.

To do this successfully, Dr. Rowley explained, environmental conditions contribute significantly to calcium carbonate sensing effectiveness. He remarked,

“It’s easier to identify calcium carbonate in drier environments.”

This study highlights the importance of selecting appropriate sites to test carbon sequestration. Further, it illustrates the ways particular environmental conditions can affect findings.

Microorganisms are going to literally dig into some of these crystals on the tree’s surface. This first step opens channels and pores to allow inorganic carbon seep deeper into the wood rigidities. Dr. Rowley elaborated on this process:

“As the calcium carbonate is formed, the soil around the tree becomes more alkaline. The calcium carbonate is formed both on the surface of the tree and within the wood structures, likely as microorganisms decompose crystals on the surface and also penetrate deeper into the tree. It shows that inorganic carbon is being sequestered more deeply within the wood than we previously realized.”

Implications for Agroforestry and Climate Action

The real-world applications of this research reach far beyond scholarly interest. Fig trees growing on limestone soil sequester significant amounts of carbon in the form of calcium carbonate, an observation that can inform agroforestry practices. Farmers can increase food yields by integrating these trees into their farming systems. This climate-friendly practice has public health benefits.

This research was truly a collaboration between three primary institutions, Nairobi Technical University of Kenya, Sadhana Forest, Lawrence Berkeley National Laboratory, University of California, Davis, and the University of Neuchatel. Their unique partnership illustrates that there is a global importance in studying and learning from local ecosystems.

Countries around the world are working toward creative approaches to address climate impacts. By understanding the unique contributions of native species such as the fig tree, they can better enhance the use of reforestation and land management practices.