Fig. 3From: Enhancing nitrogen use efficiency and yield of maize (Zea mays L.) through Ammonia volatilization mitigation and nitrogen management approachesFluxes of NH3 as affected by application of urea coated with S and S applied from gypsum. Values are means with standard error shown by vertical bars (n = 3). The solid arrows indicate the timing of N fertilization. Urea applied with 1st irrigation (1st dose) and urea applied at knee high stage (2nd dose)Back to article page