Photo credit: Edwin Remsberg and USDA-SARE
In August, a team published a proof-of-concept study in the Journal of the Electrochemical Society demonstrating that they could use electrodes to measure electric currents produced by those microbes. Detecting a current, they concluded, meant that the soil was healthy, because those microbes were conducting metabolic activity—doing things like recycling nutrients and creating compounds that help crops weather environmental stressors.
Jenny Kao-Kniffin, a professor at the School of Integrative Plant Science at Cornell University, who was not involved with the study, says she sees promise in soil scientists teaming up with engineers in this way. “A scenario where this tool could work well is to assess the impact of a management strategy on soil health or soil microbial activity, like quantifying the effect of a pesticide or fumigant on soil biological activity,” Kao-Kniffen says. “Another example is to assess the temporal changes in soil biological activity, with a shift from conventional to organic farming practices.”