Ants are ecosystem engineers that can have a large effect on the biological, chemical, and physical properties of the soil in which they live. As ants move around in the soil finding food or building underground nests, they disturb and mix up the soil around them. It’s thought that this disturbance can enhance the dissolving of minerals—known as weathering—in the soil. Studies have found that ants are one of the most effective biological enhancement weathering (BEW) agents when compared to other insects or plant roots.
In one of the most common processes of weathering, rocks rich with minerals containing calcium and magnesium come into contact with water, which breaks down the minerals. Carbon dioxide combines with these dissolved minerals to eventually form calcium or magnesium carbonate (limestone or dolomite) and clays. Because ants appear to enhance this rock dissolving process when they mix the soil, they may play a role in the drawdown of carbon dioxide from the atmosphere.
Experiments have shown that ants enhance mineral weathering 3 to 100 times more than other insect or plant agents. This increased rate of weathering due to normal ant activity may be beneficial to help keep global temperatures low by reducing carbon dioxide in the atmosphere.Edit Summary
“25 years of in-situ measurements of Ca-Mg silicate mineral dissolution by ants, termites, root mats, bare ground, and a control reveals ants to be one of the most powerful biotic weathering agents yet recognized. Six sites in Arizona and Texas (USA) indicate that eight different ant species enhance mineral dissolution by ~50×–300× over controls. A comparison of extracted soil at a 50 cm depth in ant colonies and adjacent bare ground shows a gradual accumulation of CaCO3 content for all eight ant species over 25 yr. Ants, thus, have potential to provide clues on how to enhance contemporary carbon sequestration efforts to transform Ca-Mg silicates and CO2 into carbonate.” (Dorn 2014:771)
“Given observed high BEW [biotic enhancement weathering] of ant colonies, an understanding of the geobiology of ant-mineral interactions might offer a line of research of how to geoengineer accelerated CO2 consumption by Ca-Mg silicates. Similarly, ants might also provide clues on geoengineering efficient pathways of CaCO3 precipitation to sequester atmospheric CO2.” (Dorn 2014:773)