Main content area

Nitrogen Volatilization from Arizona Irrigation Waters

Norton, E.R., Silvertooth, J.C.
Communications in soil science and plant analysis 2008 v.39 no.15-16 pp. 2378-2397
irrigation water, nitrogen content, volatilization, air temperature, water quality, nitrogen fertilizers, geographical variation, ammonium sulfate, ammonium nitrogen, nitrate nitrogen, Arizona
A laboratory study was initiated to investigate the effects of temperature (25, 30, 35, and 40 °C) and water quality on the loss of fertilizer nitrogen (N) through volatilization out of irrigation waters collected from 10 different Arizona sources. A 300-mL volume of each water source was placed in 450-mL beakers open to the atmosphere in a constant-temperature water bath with 10 mg of analytical-grade ammonium sulfate [(NH4)2SO4] dissolved into each sample. Small aliquots were drawn at specific time intervals over a 24-h period and then analyzed for ammonium (NH4 +)-N and nitrate (NO3 -)-N concentrations. Results showed potential losses from volatilization to be highly temperature dependent. Total losses (after 24 h) ranged from 30-48% at 25 °C to more than 90% at 40 °C. Volatilization loss of fertilizer N from irrigation waters was found to be significant and should be considered when making decisions regarding fertilizer N applications for crop production in Arizona particularly when using ammonia-based fertilizers.