Termites can predict climate change in African savannahs

LONDON - Scientists have said that termite mounds can be used to predict ecological shifts from climate change in the African savannahs.

Researchers at Carnegie Institution’s Department of Global Ecology used sophisticated airborne imaging and structural analysis to map more than 40,000 termite mounds over 192 square miles.

They found that their size and distribution is linked to vegetation and landscape patterns associated with annual rainfall. Mound-building termites tend to build their nests in areas that are not too wet, nor too dry, but are well drained, and on slopes of savannah hills above boundaries called seeplines.

Seeplines form where water has flowed belowground through sandy, porous soil and backs up at areas rich in clay. Typically woody trees prefer the well-drained upslope side where the mounds tend to locate, while grasses dominate the wetter areas down slope.

“These relationships make the termite mounds excellent indicators of the geology, hydrology, and soil conditions,” commented Shaun Levick.

“And those conditions affect what plants grow and thus the entire local ecosystem,” he added.

Another advantage of monitoring termite mounds is that vegetation cover varies a lot between wet and dry season, while the mounds are not subject to these fluctuations.

“The predictions are that many regions of the savannah will become drier, which suggests more woody species will encroach on today’s grasslands. These changes will depend on complex but predictable hydrological processes along hill slopes, which will correspond to pattern changes in the telltale termite mounds we see today from the air,” said Greg Asner.

The research is published in the September 7, 2010, advanced online edition of Nature Communications. (ANI)