The effects of humic acid urea and polyaspartic acid urea on reducing nitrogen loss compared with urea
Yuwen Shen, Haitao Lin, Wensheng Gao, Mingli Li
Abstract
Abstract BACKGROUND The utilization rate of urea‐N in fertilizer plays a very important role in agricultural production and environmental protection. Humic acid urea (HAU) and polyaspartic acid urea (PAU) are two similar synergistic nitrogen fertilizers. METHODS Fourier‐transform infrared spectroscopy (FTIR), X‐ray powder diffraction (XRD) and carbon‐13‐nuclear magnetic resonance ( 13 C‐NMR) were used to determine the loading of urea‐N into humic acid (HA) and polyaspartic acid (PA). Thermal stability and physical adsorption properties of HAU and PAU were assessed by thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) surface measurement. The soil incubation experiment was conducted to investigate the effects of HAU and PAU on nitrogen transformation and gaseous nitrogen loss compared with commercial urea. RESULTS Nitrogen transformation from HAU and PAU was slowed down compared with urea. After 90 days of incubation, HAU and PAU reduced the cumulative ammonia (NH 3 ) volatilization (by 9.70% and 6.30%, respectively) and nitrous oxide (N 2 O) emission (by 40.48% and 43.00%, respectively) from soil compared with the urea‐alone treatment. CONCLUSION HAU and PAU could improve the nitrogen use efficiency. © 2020 Society of Chemical Industry