22 June 2023

Based on soil sounds, ecoacoustics helps us protect forests


A study highlights the potential of ecoacoustics: by listening to ecosystem sounds, it is possible to monitor and restore forest soil health. And better assess the effectiveness of interventions

by Matteo Cavallito

Ecoacoustics, or listening to the sounds of nature, can gain important insights into the health of the ecosystem and the forest it supports. This is suggested by a study published in the journal Restoration Ecology.

The investigation, which involved researchers from Flinders University in Bedford Park, Australia, and Trent University in Nottingham, UK, applied this analysis strategy to measure the soil and subsoil biodiversity of a British forest.

The study

“We hypothesised that the soils of forests restored to a healthier state would have a higher diversity of sounds than the soils of recently deforested plots,” the authors explained in a statement released on the Australian network The Conversation. Such acoustic diversity, they point out, would be the result of a greater presence of living organisms in the regenerated soils.

During the spring and summer of 2022, the researchers collected 378 samples from three plots of Greno Woods forest near Sheffield that had been cleared in the past three years, and from three plots that had been restored for no less than 30 years. After inserting special “contact” microphones into the soil and then isolating and excluding disturbing noises such as those of wind and human activity, the scholars were able to draw interesting conclusions.

Healthy soil is also more tuneful

“Restored soils had significantly higher invertebrate abundance than deforested soils,” the research states. “Soil invertebrate community composition was significantly different between deforested and restored plots. Earthworms were the dominant invertebrate in the soil for both treatment groups and were more abundant in the restored plots.”

The authors compared forest soil to an orchestra: a degraded ecosystem reckons with the absence of part of its “musicians” and, as such, produces less elaborate sounds. “In contrast, the other orchestra has all its members and will therefore be louder, with more complex and diverse sounds,” they say. The results of the study “confirmed our suspicions that healthier soil would be more tuneful.”

Ecoacoustics can help us protect forests and climate

With ecoacoustics, the study notes, it is possible to monitor the health of the soil that underlies our food systems and supports all other life on earth. “The “unseen” and “unheard” organisms living in the soil maintain its health,” the researchers explain. “Below-ground organisms, such as earthworms and beetles, play a crucial role in nutrient cycling and soil health. Without them, forests can’t thrive.”

Sound analysis, in short, also makes it possible to better assess the effectiveness of restoration efforts. Thus enabling better decisions to be made in counteracting climate change related to deforestation and the subsequent release of carbon stored in forests.

“The use of ecoacoustics in restoration efforts is still relatively new, but it’s an important step towards a more holistic and effective approach to ecosystem recovery,” the researchers conclude. “By embracing new technologies and approaches, we can work towards a healthier and more sustainable planet.”