Assessment of Microbial Dynamics in Soil under Peroxide-Aeration Treated Cassava Effluent: Impacts on Soil Health and Potential Plant Productivity

Abstract

This study assessed the impact of cassava processing effluent (CPE) treated via peroxide aeration on microbial soil dynamics, and its potential impact on plant productivity. Soil microbial counts, and soil respiration were examined under raw wastewater and peroxide-aeration combination treated effluent dilutions (0, 25, 50, 75, and 100%). The initial soil bacterial load in the soil of 3.20 x 108 CFU/g soil was increased to 8.90 x 108 CFU/g soil in raw wastewater, while dilutions using treated effluent exhibited modest increases from 6.55 to 6.69 x 108 CFU/g soil. The same pattern was observed in fungal populations, which increased from 3.00 to 64.00 x 108 CFU/g soil under raw wastewater and 18.6 to 19.00 x 108 CFU/g soil under dilution treatments. Soil respiration increased from 10.35 to 13.40 mg CO₂-kg⁻¹ day⁻¹ under the 50% dilution, indicating enhanced microbial activity. These results showed that reuse of cassava effluent can enhance soil microbial activities central to nutrient cycling and soil fertility. However, the highest microbial population and respiration under raw wastewater point toward the possibility of hazards such as microbial imbalance and toxic compounds like cyanide build-up. The moderate dilution levels, especially 50%, provided a compromise between stimulation of microbial activity and minimization of negative effects, which is aligned with sustainable agricultural management practice. It is concluded that careful dilution management of peroxide-aerated cassava effluent is key to maximizing soil health benefits while minimizing risks.