Azra Hoosen | ah@radioislam.co.za
9 November 2024 | 14:00 CAT
4 min read

In a ground-breaking discovery in South Africa’s Namaqualand, scientists from Stellenbosch University have uncovered a 34,000-year-old termite mound, revealing the ancient and surprising role of termites in enhancing ecosystems and fighting climate change.

Researchers Cathy Clarke and Michele Francis found that these tiny insects act as natural engineers, enriching the soil, boosting biodiversity, and storing carbon over millennia. This remarkable find challenges the traditional view of termites as pests and could revolutionise our understanding of their potential in global carbon models, offering new hope in the fight against climate change.

What brought soil scientists Cathy Clarke and Michele Francis to Buffelsrivier was their interest in understanding why the groundwater there was saline but not uniformly so. They hypothesised that the salt in the termite mounds might be contributing to the groundwater salinity, which led them to excavate the mounds.

Professor Cathy Clarke told Radio Islam: “We saw these deep termite nests while excavating, and they were very hard; that is when we realised these things must be pretty ancient; that’s what led us to carbon date those mounds.”

This ancient mound, created by southern harvester termites, was initially part of a project to understand the region’s hypersaline groundwater. However, the excavation revealed much more than expected.

She said they found exactly what they were looking for – and a little extra. “It was a bit of luck that we found this while excavating, but that’s how science goes right,” she joked.

The tests on soil and organic materials from the mound revealed that the termites have been active in the area for at least 19,000 years, with some materials dating back 34,000 years to before the last Ice Age. The findings highlight the termites’ role as ecosystem engineers—redistributing organic matter and altering soil composition. This has allowed for the growth of distinct plant species, contributing to the incredible biodiversity of the Namaqualand region, which is considered the world’s most biodiverse desert.

“We have come up with pretty good evidence that these mounds are contributing to groundwater salinity; these mounds have sat in our landscaping for tens of thousands of years. With the marine fog that blows off the Atlantic, that fog often settles on plants, and then the termites gather that plant material in, so they are constantly accumulating salts,” she said.

The research also sheds light on the termites’ unexpected role in combating climate change. By collecting sticks and twigs and dragging them underground, termites store organic carbon deep in the soil, reducing the chances of it being released into the atmosphere. Moreover, the biological breakdown of their excrement leads to the formation of calcium carbonate, a stable form of carbon that can be locked in the soil for thousands of years.

Clarke highlighted that termites also accumulate nutrients; she referred to them as “nutrient hotspots”. She also pointed out that recent research has revealed termites are creating carbon sinks, which has been an exciting discovery for them.

The termites’ activity has turned their mounds into long-term carbon sinks, storing approximately 14.6 metric tonnes of carbon per mound. This accidental discovery has led researchers to suggest that termite mounds could be an important factor in carbon sequestration models, which traditionally focus on forests and oceans.

Clarke explained that in addition to their carbon storage abilities, termites also support a variety of other species. For instance, a species of hoverfly relies on termite frass as a larval habitat. Without termites, this species could go extinct.

“Termites are often misunderstood,” she explained. They’re typically seen as pests, but we don’t fully understand their ecological roles. The tide is turning as more studies highlight the benefits termites bring to environments, especially in terms of nutrients and carbon cycling. Not all termite species are the same—the southern harvester termites in the Western Cape, for example, are not pests at all. They play a crucial role in the ecosystem.

“You have got diversity on top of diversity. When you talk about an ecosystem engineer, it is an organism that stimulates the environment and the ecosystem. The termite is a wonderful forgotten organism that works silently behind the scenes but creates so much diversity,” she said.

She stressed the need for greater awareness and more research to differentiate between harmful species and those that should be protected for their vital ecological functions.

“We are only looking at one side; termites can also be a great generator of methane, so we need to understand what their emissions are, which has just not been researched; that is what we would like to look at next to get a better understanding of the net carbon capture of these mounds and their importance in terms of land management,” she said. Clarke joked, “As scientists always, requires further work.”

Scientists believe studying termite activity further could enhance our understanding of carbon dynamics and how termite mounds could help in fighting climate change.

LISTEN to the full interview with Muallimah Annisa Essack and Professor Cathy Clarke – Chair and Associate Professor in the Department of Soil Science at Stellenbosch University, here.