TY - JOUR
T1 - Comparison of urease inhibitor N-(n-butyl) thiophosphoric triamide and oxidized charcoal for conserving urea-N in soil
AU - Guimarães, Gelton G.F.
AU - Mulvaney, Richard L.
AU - Khan, Saeed A.
AU - Cantarutti, Reinaldo B.
AU - Silva, Antônio M.
N1 - Publisher Copyright:
Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2016/8/1
Y1 - 2016/8/1
N2 - Charcoal-based amendments have a potential use in controlling NH3 volatilization from urea fertilization, owing to a high cation-exchange capacity (CEC) that enhances the retention of NH $ _4^+ $. An incubation study was conducted to evaluate the potential of oxidized charcoal (OCh) for controlling soil transformations of urea-N, in comparison to urease inhibition by N-(n-butyl) thiophosphoric triamide (NBPT). Four soils, ranging widely in texture and CEC, were incubated aerobically for 0, 1, 3, 7, and 14 d after application of 15N-labeled urea with or without OCh (150 g kg−1 fertilizer) or NBPT (0.5 g kg−1 fertilizer), and analyses were performed to determine residual urea and 15N recovery as volatilized NH3, mineral N (as exchangeable NH $ _4^+ $, NO $ _3^ - $, and NO $ _2^ - $), and immobilized organic N. The OCh amendment reduced NH3 volatilization by up to 12% but had no effect on urea hydrolysis, NH $ _4^+ $ and NO $ _3^ - $ concentrations, NO $ _2^ - $ accumulation, or immobilization. In contrast, the use of NBPT to inhibit urea hydrolysis was markedly effective for moderating the accumulation of NH $ _4^+ $, which reduced immobilization and also controlled NH3 toxicity to nitrifying microorganisms that otherwise caused the accumulation of NO $ _2^ - $ instead of NO $ _3^ - $. Oxidized charcoal is not a viable alternative to NBPT for increasing the efficiency of urea fertilization.
AB - Charcoal-based amendments have a potential use in controlling NH3 volatilization from urea fertilization, owing to a high cation-exchange capacity (CEC) that enhances the retention of NH $ _4^+ $. An incubation study was conducted to evaluate the potential of oxidized charcoal (OCh) for controlling soil transformations of urea-N, in comparison to urease inhibition by N-(n-butyl) thiophosphoric triamide (NBPT). Four soils, ranging widely in texture and CEC, were incubated aerobically for 0, 1, 3, 7, and 14 d after application of 15N-labeled urea with or without OCh (150 g kg−1 fertilizer) or NBPT (0.5 g kg−1 fertilizer), and analyses were performed to determine residual urea and 15N recovery as volatilized NH3, mineral N (as exchangeable NH $ _4^+ $, NO $ _3^ - $, and NO $ _2^ - $), and immobilized organic N. The OCh amendment reduced NH3 volatilization by up to 12% but had no effect on urea hydrolysis, NH $ _4^+ $ and NO $ _3^ - $ concentrations, NO $ _2^ - $ accumulation, or immobilization. In contrast, the use of NBPT to inhibit urea hydrolysis was markedly effective for moderating the accumulation of NH $ _4^+ $, which reduced immobilization and also controlled NH3 toxicity to nitrifying microorganisms that otherwise caused the accumulation of NO $ _2^ - $ instead of NO $ _3^ - $. Oxidized charcoal is not a viable alternative to NBPT for increasing the efficiency of urea fertilization.
KW - N
KW - NBPT
KW - ammonia volatilization
KW - fertilizer efficiency
KW - immobilization
KW - oxidized charcoal
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U2 - 10.1002/jpln.201500622
DO - 10.1002/jpln.201500622
M3 - Article
AN - SCOPUS:84982938646
SN - 1436-8730
VL - 179
SP - 520
EP - 528
JO - Journal of Plant Nutrition and Soil Science
JF - Journal of Plant Nutrition and Soil Science
IS - 4
ER -