'Nasty' termites' dirt mounds help prevent spread of deserts

"Not all termites are pest" because a new research has revealed that dirt mounds made by termites are crucial to stopping deserts from spreading into semi-arid ecosystems.

The National Science Foundation study found that in the parched grasslands and savannas, or drylands, of Africa, South America and Asia, termite mounds store nutrients and moisture and via internal tunnels, allow water to better penetrate the soil.

As a result, vegetation flourishes on and near termite mounds in ecosystems that are otherwise vulnerable to desertification.

Researcher Doug Levey said that this study demonstrates that termite mounds create important refugia for plants and help to protect vast landscapes in Africa from the effects of drought, adding not all termites are pests.

The research was inspired by the fungus-growing termite species, Odontotermes, but the results apply to all types of termites that increase resource availability on or around their mounds.

Corresponding author Corina Tarnita, a Princeton University ecologist, added that because termites allow water to penetrate the soil better, plants grow on or near the mounds as if there were more rain and the vegetation on and around termite mounds persists longer and declines slower.

Tarnita noted that even when there is harsh conditions where vegetation disappears from the mounds, re-vegetation is still easier, suggesting as long as the mounds are there the ecosystem has a better chance to recover.

Ecologist Robert Pringle said that the unexpected function of termites in savannas and grasslands suggests that ants, prairie dogs, gophers and other mound-building creatures could also have important roles in ecosystem health.

Pringle added that he likes to think of termites as linchpins of the ecosystem in more than one way as they increase the productivity of the system, but they also make it more stable and more resilient.

The study is published in the journal Science.