Application of Chemical Stabilizers to Sustain Urease Inhibition in Soil–Plant Systems

Abstract

Nitrogen fertilizers play a crucial role in enhancing crop yield and quality in agricultural production. However, urea, as a major nitrogen source, is rapidly hydrolyzed by urease in soil, leading to nitrogen loss through ammonia volatilization or nitrate leaching. This not only reduces fertilizer use efficiency but also increases environmental pollution. Urease inhibitors can delay urea decomposition and improve nitrogen utilization, but their activity in soil is often rapidly diminished due to temperature, moisture, and microbial activity, limiting their long-term application. The introduction of chemical stabilizers provides a new strategy to prolong the effective period of urease inhibitors. In this study, urea and urease inhibitors were applied in a simulated soil–plant system, with the addition of different types of chemical stabilizers. The effects on urease activity, soil nitrogen dynamics, and plant growth and nitrogen uptake were systematically evaluated. The results showed that chemical stabilizers significantly slowed the degradation of urease inhibitors, maintaining low soil urease activity for an extended period. Correspondingly, ammonia volatilization was markedly reduced, and nitrate retention increased, indicating effective control of soil nitrogen loss. Meanwhile, plant nitrogen uptake and growth performance were improved, demonstrating that stabilizers can not only prolong the inhibitory effect but also promote crop growth. Mechanistic analysis suggested that chemical stabilizers may extend inhibitor activity by forming protective complexes with the inhibitors or by reducing microbial degradation rates. This strategy has significant potential for agricultural applications, as it can improve nitrogen use efficiency, reduce environmental pollution, and provide a theoretical basis for optimizing soil–plant nitrogen management. Future studies could further explore the effectiveness and applicability under different soil types, crop species, and long-term field conditions.