Electrolysis‐treated biosolids enhance wheat growth and alter soil health parameters

Abstract

Biosolid‐based fertilizers can benefit agriculture by supporting circular nutrient economies, reducing fertilizer costs, and minimizing environmental impacts compared to inorganic fertilizers. A 125‐day greenhouse experiment was conducted to assess the effects of electrolysis‐treated biosolids on wheat ( Triticum aestivum ) growth and soil health parameters. Treatments included electrolysis‐treated biosolids (E‐GROW), raw biosolids (RB), inorganic nutrient solution (NS), composted biosolids (Dillo Dirt), and an unamended Control. Average germination across treatments was 91% (±9%) with no significant differences. Permanganate oxidizable carbon, microbial biomass carbon and nitrogen were increased in soils amended with biosolid products. E‐GROW resulted in significantly higher soil nitrate (2.35x higher than NS; 1.69x higher than Dillo Dirt) and extractable phosphorus (1.89x higher than RB). E‐GROW produced approximately 32% higher wheat biomass than RB and Dillo Dirt, 42% higher than Control, while comparable to NS. Agronomic and recovery efficiencies of phosphorus were found to be higher in E‐GROW compared to Dillo Dirt. Trace metal (Mo, Ni, Pb, V, As, Ce, Cr, and La) concentrations were below the US Environmental Protection Agency limits in all products and amended soil. Fecal coliforms were not detected in E‐GROW‐amended soils at the end of the experiment, indicating effective pathogen inactivation by electrolysis. These results suggest that electrolysis‐treated biosolids have potential value as a soil amendment for promoting a circular nutrient economy. However, long‐term field studies are needed to evaluate nutrient dynamics, contaminants, and in‐field crop productivity before widespread agricultural adoption.