A global research project has uncovered new findings on how insects aid in the decomposition of wood, giving vital insights into their role in the carbon cycle and the health of forests around the world.

International research teams worked in 55 different locations spanning six continents, recently determined the annual contribution made by deadwood to the global carbon cycle and quantified the importance of insects in the decomposition of wood for the first time.

Reader in Ecology at Edge Hill University, Dr Anne Oxbrough, led the UK research group taking part in the project.

Anne said: “It has been really exciting to represent the UK in this global project looking at woodlands and forests, from the boreal to the tropics.

“While it’s been known for some time that fungi are essential to breaking down wood, the precise role and importance of insects in the process has remained a mystery.

Whilst insect populations are declining due to climate change and habitat loss, this new research shows that a drop in insect numbers could lead to huge changes to the carbon cycle across the world, with unknown effects for the carbon cycle and forests around the world.

“It was clear that wood without access to insects decomposes much more slowly.” Anne explained. “And, in the tropics, insects accounted for almost one third of wood decomposition. If we continue to see a decline in insect populations this would have a massive effect on rates of wood decomposition, and through it, the global carbon cycle.”

The project was led by PD Dr Sebastian Seibold from the Technical University of Munich (TUM) who worked with colleagues to test more than 140 tree species to assess the influence of insects, fungi and the climate on the rate of decomposition. Amongst the international research team, Edge Hill University colleagues set up the three-year experiment in Roudsea Wood in Cumbria. They placed different species of dead wood in special mesh cages to exclude insects and left another set of wood exposed for insects to find.

Dr Werner Rammer, a scientist at TUM who played the leading role in the global calculations added: “According to the report, some 10.9 giga-tons of carbon are released from deadwood worldwide every year. In this context, part of the carbon is absorbed into the soil, while another part is released into the atmosphere. The amount of carbon released from deadwood is equivalent to roughly 115 percent of the emissions from fossil fuels.” 

PD Dr Sebastian Seibold said: “At a time of global change, we can see some dramatic declines in biodiversity and changes in climate. This study has demonstrated that both climate change and the loss of insects have the potential to alter the decomposition of wood, and therefore, the carbon and nutrient cycles worldwide.”

It is hoped this research will provide evidence to support global policy, which will be part of the discussion at COP26 climate change conference in Glasgow next month.

The full research paper can be found using this link: https://rdcu.be/cwBDZ.

Edge Hill offers degrees in BiologyPlant Science and Ecology and Conservation. For more information about the range of BioSciences degree courses on offer at Edge Hill University, visit edgehill.ac.uk/study/undergraduate/biosciences/.