Termite mounds ''can halt desert''s advance''

Termites, the pesky insects whose fondness for wood makes them the bane of homeowners, help halt desertification in semi-arid areas and protect against the effects of climate change, a study has said.

In grasslands, savannahs and arid areas of Africa, Latin America and Asia, termite mounds, which store moisture and nutrients and contain multiple tunnels, allow water to better penetrate the ground, said the authors of the study in the journal Science.

Vegetation thrives on termite mounds in ecosystems vulnerable to desertification.

"The rain is the same everywhere, but because termites allow water to penetrate the soil better, the plants grow on or near the mounds as if there were more rain," said lead study author Corina Tarnita of Princeton University.

"Even when you get to such harsh conditions where vegetation disappears from the mounds, revegetation is still easier. As long as the mounds are there, the ecosystem has a better chance to recover."

Jef Huisman, an aquatic microbiology professor and theoretical ecologist at the University of Amsterdam who did not participate in the research, said the research shows that early warning signals for desertification were too simple in the past, and failed to take into account nature's complexities.

According to current models, there are five stages in the transition to desert, each with specific characteristics in terms of vegetation growth, and scientists can use satellite images to determine an area's desertification stage.

But semi-arid ecosystems with termite mounds and those in the fifth and last stage appeared very similar, the researchers said.
 

Giant Northern or Mastotermes darwiniensis worker termites. (Photo credit: CSIRO Australia)

The scientists thus showed that what had appeared to be the final stage before desertification was sometimes the total opposite, thanks to termite mounds.

Climate models, Huisman added, should better take into account the impact of organisms such as termites and mussels that "engineer their own environment."

Ants, prairie dogs, gophers and other mound-building creatures could play an important role in the ecosystem, said co-author Robert Pringle, assistant professor in ecology and evolutionary biology at Princeton.

"I like to think of termites as linchpins of the ecosystem in more than one way," Pringle said.

"They increase the productivity of the system, but they also make it more stable, more resilient."

AFP