By dragging sticks and twigs underground, the termites add fresh stores of organic carbon to the ground at depths greater than one metre (three feet). This deep storage of organic carbon, explains Clarke, “reduces the likelihood of the carbon being released back into the atmosphere and means that the mound acts as a long-term carbon sink”. The continual harvesting of plant matter also increases the fertility status of these mounds. Hence the halos of spring flowers.
But the termites’ powers of sequestration don’t end there. The biological breakdown of termite excrement (known as frass) triggers a cascade of biological reactions, which results in the formation of calcium carbonate – the material limestone is made of. This calcium carbonate is a very stable form of carbon that is locked in the soil for thousands of years. Some of this carbon leaches into groundwater where it may remain for centuries.
“This is the kind of long-term carbon storage [14.6 metric tonnes] method that carbon storage companies are trying to replicate,” says Clarke. “But the termites have been doing it for thousands of years.
