Soil is one of our most precious resources. Ecoacoustics, or the study of environmental sounds, has been around for a century, but it has only recently been applied to understanding soils. This emerging approach, called “soilsmology,” uses sound waves to assess soil health with minimal disturbance.
Traditional soil sampling requires digging holes and taking samples to be analyzed in a laboratory. It is messy, time-consuming, and expensive, and it often damages the very soil it aims to protect and improve.
Soilsmology involves placing a metal plate on the ground, striking it with a hammer, and monitoring how the seismic waves move through the earth. The way the waves bounce back provides a remarkably detailed picture of conditions underground. The waves rebound off rocks and compacted soil, making their way back to the surface through all the interstices in the soil. Each type of soil microorganism has its own sound profile. The waves pick up the differing footprints of these tiny underground creatures — earthworms, millipedes, and microbes — as well as moisture levels.