Ecoacoustic studies at Flinders University suggest that healthier soils have more complex soundscapes, suggesting a novel tool for environmental restoration.
Healthy soils produce a cacophony of sounds in many forms that are barely audible to the human ear – a bit like a concert of popping and clicking soap bubbles.
In a new study published in Journal of Applied EcologyEcologists at Flinders University have made special recordings of this chaotic mix of soundscapes. Their research shows that these ground acoustics may be a measure of the diversity of tiny creatures in the soil that make sounds as they move and interact with their environment.
With 75% of the world’s soils degraded, the future of the teeming community of living species that life underground faces a bleak future without restoration, says microbial ecologist Dr. Jake Robinson of the Limits of restoration ecology Laboratory in the College of Science and Engineering, Flinders University.
This new field of research aims to study the vast, species-rich hidden ecosystems in which almost 60 percent of all species on Earth live, he says.
Advances in ecoacoustics
“Restoring and monitoring soil biodiversity has never been more important.
“Although ecoacoustics is still in its early stages, it is emerging as a promising tool for detecting and monitoring soil biodiversity and is now being used in Australian bushland and other ecosystems in the UK.
“The acoustic complexity and diversity are significantly higher on replanted and residual areas, both on site and in soundproofing chambers, than on cleared areas.
“The acoustic complexity and diversity are also significantly related to the abundance and diversity of soil invertebrates.”
The study, which also included expert Associate Professor Martin Breed from Flinders University and Professor Xin Sun from the Chinese Academy of Sciences, compared the results of acoustic monitoring of remnant vegetation with degraded plots and land that was replanted 15 years ago.
Passive acoustic monitoring used various tools and indices to measure soil biodiversity over five days in the Mount Bold region of the Adelaide Hills, South Australia. A subsurface sampling device and sound attenuation chamber were used to record soil invertebrate communities, which were also manually counted.
“It is clear that the acoustic complexity and diversity of our samples are related to the abundance of soil invertebrates – from earthworms and beetles to ants and spiders – and appear to be a clear indicator of soil health,” says Dr Robinson.
“All living organisms produce sounds and our preliminary results suggest that different soil organisms produce different sound profiles depending on their activity, shape, limbs and size.
“This technology holds great promise in meeting the global need for more effective methods to monitor soil biodiversity and thus protect our planet’s most diverse ecosystems.”
Reference: “Sounds of the underground reflect soil biodiversity dynamics across a grassy woodland restoration chronoseqence” by Jake M. Robinson, Alex Taylor, Nicole Fickling, Xin Sun and Martin F. Breed, August 15, 2024, Journal of Applied Ecology.
DOI: 10.1111/1365-2664.14738
