The effect of urea-ammonium-nitrate fertilizer amended with urease and nitrification inhibitors on nitrogen cycling in highly organic agricultural soil

Starting in the mid 20th century the use of nitrogen fertilizers has steadily increased due to the rising demand in food production. Currently, urea-based nitrogen fertilizers are the most commonly used source of nitrogen in agriculture worldwide. Although there are benefits to urea fertilizers (high nitrogen content, high solubility, and low cost), its rapid decomposition to ammonia and carbon dioxide could lead to environmental and human health concerns. Laboratory experimentation was conducted to determine the rate of urea decomposition, ammonia volatilization, influence of soil moisture on urea decomposition, potential for fertilizer loss below the rooting zone, and the response of the microbial community to fertilization of highly organic agricultural soil with urea-ammonium-nitrate (UAN). In addition, urease and nitrification inhibitors were added to UAN fertilizer in order to determine if these amendments altered the rate of N transformations in soil