Potential Application of Urease and Nitrification Inhibitors to Mitigate Emissions from the Livestock Sector: A Review
Human activities have caused an increase in greenhouse gas emissions, resulting in climate change that affects many factors of human life including its effect on water and food quality in certain areas with implications for human health. CH<sub>4</sub> and N<sub>2</sub>O are known as potent non-CO<sub>2</sub> gases. The livestock industry contributes to direct emissions of CH<sub>4</sub> (38.24%) and N<sub>2</sub>O (6.70%) through enteric fermentation and manure treatment, as well as indirect N<sub>2</sub>O emissions via NH<sub>3</sub> volatilization. NH<sub>3</sub> is also a secondary precursor of particulate matter. Several approaches have been proposed to address this issue, including dietary management, manure treatment, and the possibility of inhibitor usage. Inhibitors, including urease and nitrification inhibitors, are widely used in agricultural fields. The use of urease and nitrification inhibitors is known to be effective in reducing nitrogen loss from agricultural soil in the form of NH<sub>3</sub> and N<sub>2</sub>O and can further reduce CH<sub>4</sub> as a side effect. However, the effectiveness of inhibitors in livestock manure systems has not yet been explored. This review discusses the potential of inhibitor usage, specifically of N-(n-butyl) thiophosphoric triamide, dicyandiamide, and 3,4-dimethylpyrazole phosphate, to reduce emissions from livestock manure. This review focuses on the application of inhibitors to manure, as well as the association of these inhibitors with health, toxicity, and economic benefits.