Researchers at the University of Western Australia, in collaboration with the University of Liverpool, the Natural History Museum in London, and the University of Malaysia, Sabah, found that termites play a key role in helping rainforest plants survive the dry.
The new finding published today in Science has important implications for the conservation of tropical forests. Although rainforests cover only 2 percent of the Earth's surface, they contain about half of the world's terrestrial biodiversity, the highest of any global ecosystem. However, the impact of climate change poses a growing threat to its survival.
UWA associate professor Theodore Evans, who played a leading role in the study, said termites were among the most abundant animals in the rainforests.
"The large number of termites suggest that these insects play important roles in tropical forest ecosystems, but that role has never been understood until now," Professor Evans said.
"This is due in part to their small size and, because they live underground, makes them harder to study compared to other larger animals."
In the study, researchers measured the role of termites and their abundance in the Borneo Forest during the 2015-2016 El Niño drought event.
"We used bait methods to reduce termite populations at a study site in the Borneo Forest, and compared them to another unmanaged study site," Professor Evans said.
"What we found was that termite activity doubled during the drought with them eating up to 40% more litter. The digested litter was then returned to the soil as nutrients, with termites affecting the distribution of various soil nutrients, including nitrogen, potassium and other metals, revealing that current models are underestimating the carbon flux in the atmosphere during periods of drought.
Professor Evans said that termites must live in wet conditions during drought, which brought groundwater to the soil surface, and increased soil moisture to about 36%, increasing seedling survival by 51% during dry.
The study is the first to measure the positive effects of termites on tropical forests in reducing the impact of droughts on plants. The results confirmed the prediction of the famous biologist of Harvard University, Professor E.O. Wilson, termites are "one of the little things that command the world," because they influence the processes that help the plants, on which we all depend.
"The study provides further evidence on the importance of conserving important natural ecosystems, understanding their biology so that we can protect them in a time of rapid environmental change," said Professor Evans.
Image: Macrotermes gilvus solider termites defending their hill, courtesy of Jan Šobotník
Associate Professor Theodore Evans (UWA School of Biological Sciences) 08 6488 8672/0419 482 876
Jess Reid (Public Relations and Public Relations Advisor at UWA) 08 6488 6876