H. Cantarella, R. Otto, J. Soares
May 24, 2018
Citations
18
Influential Citations
249
Citations
Quality indicators
Journal
Journal of Advanced Research
Abstract
Graphical abstract Schematic diagram of urea dissolution, diffusion and hydrolysis in the soil. (a) Without an inhibitor, hydrolysis is fast (dark blue color) causing NH3/NH4+ accumulation and increasing the pH close to the soil surface around the fertilizer granule, driving NH3 volatilization. As the ammonia species are less mobile in soil, diffusion is limited. (b) The inhibitor maintains urea unhydrolyzed for some time. Urea has no electrical charges and diffuses easily into the soil solution. When the effect of the inhibitor phases down and urea starts to hydrolyze, both the pH and the NH3/NH4+ concentrations are lower (light blue color) as a result of dilution. Part of the urea is incorporated into the soil before hydrolysis; the NH3 produced inside the soil is retained by the negative charges of colloidal material and losses are reduced even if no rain or irrigation incorporates urea into the soil.