By Maitrayee Basu
When we think about termites, we know they are bad news. Let me share an anecdote. I lived in a house once that was forty years old in Australia. My mother was walking down our hallway on her heels for an event we were about to leave for. Out of nowhere, I heard my mother groan and something fall on the floor. I ran out of my room to see my mother standing, holding the chair for support and folders scattered around her feet. That’s when I noticed that one of her heels had pierced through the floorboards. But how? The answer: termites. They had been chewing through the wood panels of our house 2 years into buying it.
Only 4% of the 3,000 termite species are known pests, but the rest are known for contributing to 2% of global carbon emissions. Talk about a bad reputation. At the same time, termites perform an important ecological roles as decomposers. Known as the most dominant macro-invertebrate group, they have high biomass in many tropical ecosystems and impact soil function and nutrient cycling.
These seemingly mixed signals may leave you wondering – what is their exact role?
In a recent paper published by Science, a team of scientists descended in a patch of rainforest in the Maliau Basin in Malaysian Borneo to determine just that. The basis of their research focused on the hypothesis that termites mitigate the effects of drought in tropical rainforests, and experiments were conducted to quantify their role during the 2015-2016 “super El Niño” drought in the Malaysian rainforest. To their knowledge, termites “engineered” their way through the ecosystem, digging tunnels and chewing on fallen dead food, literally vacuuming the forest floors of dead material and dispersing it into the system to be used by other plants or animals. Termites also regulate soil moisture by transporting water upward through the soil which can reduce the water stress experienced by plants.
Thus, to quantify the role of termites, researchers set up a controlled spot in the rainforest where they dropped little piles of poisoned cellulose, such as paper that only termites could digest but also killed them. It turned out that during the drought, areas where termites hadn’t been poisoned, soil stayed moist due to their regular activity. Seedlings sprouted in this soil and acted as a buffer to the drought.
So in answer to our questions about meeting the challenges of climate change, termites might just be a key answer. The conclusion reached was that termites are sensitive to changes in soil moisture and may be more abundantly active in rainforests during drought. Droughts are becoming more severe as climate change progresses, causing stress to the rainforest. An increase in termite activity during these extended dry periods could help maintain soil moisture, facilitate the movement of soil nutrients, and create a heterogeneous environment.
The mechanisms driving the termite activity in helping rainforests are not completely understood. No other decomposer group are more active than the termites. If only they had reduced predation pressure from ants and a high survival rate from climate change… Yet who knew that these little creatures would end up being an unsung hero for rainforests.
In this time of climate change and increased discussion of mitigating its effects, the value of tropical forests still goes unnoticed for how much of an important role they can play. While the termites play their role in protecting the rainforest, through Rainforest Partnership’s projects and your help, we too can assist!
1 Termites mitigate effects of drought in tropical rainforests – ScienceDaily
2 Global Impact of Termites on the Carbon Cycle and Atmospheric Trace Gases – ResearchGate
- Borunda, A. (2019). How termites help rainforests survive climate change. [online] Nationalgeographic.com. Available at: https://www.nationalgeographic.com/environment/2019/01/termites-protect-rainforests-climate-drought/ [Accessed 16 Jan. 2019].
- L. A. Ashton et al. Termites mitigate the effects of drought in tropical rainforest. Science, 2019 DOI: http://science.sciencemag.org/content/363/6423/174.editor-summary
- The University of Hong Kong. “Termites mitigate effects of drought in tropical rainforests.” ScienceDaily. ScienceDaily, 10 January 2019. <www.sciencedaily.com/releases/2019/01/190110141753.htm>.
- Sugimoto, Atsuko & Bignell, David & A. MacDonald, Jannette. (2000). Global Impact of Termites on the Carbon Cycle and Atmospheric Trace Gases. https://www.researchgate.net/publication/289846016_Global_Impact_of_Termites_on_the_Carbon_Cycle_and_Atmospheric_Trace_Gases