Termites may expand their range southwards due to rising temperatures

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Termites may expand their range southwards due to rising temperatures

As the temperature rises, Termites are likely to expand their range southwards.

The findings of a new global study published in the journal Science show that insects may accelerate the emission of carbon into the atmosphere as that spread takes place.

The role of termites and microbes in the decomposition of deadwood was examined by scientists.

They found microbes behaved according to well-established trends, but the role of termites in breaking down wood became disproportionately higher as the temperature increased.

For every 10 degrees Celsius increase in the temperature, termites can increase in decomposition by up to seven times, said Alex Cheesman, a senior research fellow at James Cook University in Cairns.

The idea for the study came at a research workshop in the world heritage-listed Daintree Rainforest in far north Queensland.

More than 100 collaborators have been involved, setting up a network of 133 sites across every continent except Antarctica.

Two blocks of PInus radiata, a type of wood commonly used in house frames, were placed at each site to measure the relative roles of termites and microbes in breaking down the wood.

Termites are already found in cooler areas, such as Tasmania, but they usually play a more limited role in wood decay there compared to fungi and microbes.

The extent to which termites could only be found in the tropics might spread south, or northward in the northern hemisphere, is not yet known, according to Dr Cheesman.

He said that a 2 C or 3 C rise could cause a significant expansion of their home range, and we are expecting a 2 C or 3 C rise.

The consequences a termite expansion could have on natural ecosystems are still to be determined.

As the temperature warms, increased termite activity will send carbon back into the atmosphere faster, fuelling further warming.

The huge impact that termites could have on carbon cycling and interactions with climate change is not accounted for, according to the University of Miami tropical biologist Amy Zanne, a researcher and university of Miami tropical biologist.

According to Cheesman, termites can transfer carbon into methane when they break wood down, unlike microbes.

He said that methane actually has a greater warming potential than CO 2 itself.

He said it was important to understand the risks of positive feedback loops, which mean you have uncontrolled carbon release. Cheesman said that this research focused on the role of termites in natural systems rather than the four per cent of termites considered pests.

James Cook University researchers will work on a project next month with colleagues in Miami to look at the effect termites have on standing biomass rather than deadwood.