Sensitivity of soil CO2 emissions to fertilizer nitrogen species: urea, ammonium sulfate, potassium nitrate, and ammonium nitrate

Abstract

Batch aerobic incubation experiment was conducted using an acidic loam soil for 110 days with five N treatments: no N [Control], (NH 2 ) 2 CO [U], (NH 4 ) 2 SO 4 [AS], KNO 3 [PN], and NH 4 NO 3 [AN]. Cumulative amount of CO 2 emission (mg · C/kg) was 1066.5 [U], 951.4 [AS], 753.8 [PN] and 847.0[AN] during the entire incubation period. Sensitivity of soil organic carbon (SOC) mineralization (expressed as the ratio of the amount of N fertilization-induced CO 2 -C emission to a given amount of N addition) was greatest in U followed by AS, AN, and PN treatments, suggesting that application of NO 3 --based fertilization would be helpful in reducing fertilizer-induced SOC mineralization in agricultural soils.

High resolution short-term investigation of soil CO2, N2O, NOx and NH3 emissions after different chabazite zeolite amendments

“…In the present work, it has to be noticed that cumulative CO2 emissions were similar between fertilized and unfertilized conditions, highlighting that microbial activity was high in this agricultural soil even without adding a fresh N-C input. Concerning this aspect, contrasting effects were reported in the scientific literature; while urea fertilization was found to increase soil CO2 emissions because of increased mineralization of soil organic carbon by heterotrophic bacteria (Choi et al, 2011), the opposite effect was reported by Wilson and Al-Kaisi (2008) after fertilization with NH4NO3. However, the reason why no significant differences in CO2 emissions were observed under unfertilized conditions is hard to explain without a more detailed investigation on treatment specific microbial CUE and CO2 adsorption mechanisms.…”

Alterations of ecosystem nitrogen status following agricultural land abandonment in the Karst Critical Zone Observatory (KCZO), Southwest China

“…In agroecological systems, crops mainly absorb bioavailable N (NH 4 + and NO 3 − ) from chemical N fertilizer ( Choi, Matushima & Ro, 2011 ; Muhammed et al., 2018 ). In addition, some leguminous crops can utilize atmospheric N through symbiotic N 2 fixing ( Hogberg, 1997 ).…”

Stable nitrogen and carbon isotope compositions in plant-soil systems under different land-use types in a red soil region, Southeast China

“…For example, applying manure with a low C/N ratio enhances the SON mineralization rate, which produces 15 N-depleted ammonium ( ) and causes 15 N enrichment in residual organic matter and microbes ( Choi et al, 2017 ; Koopmans et al, 1997 ). Applying fertilizer accelerates nitrification and NH 3 volatilization, which causes 15 N enrichment in residual and produces 15 N-depleted and NH 3 , respectively ( Choi, Matushima & Ro, 2011 ). Applying fertilizer affects denitrification and increases -N leaching loss.…”

“…Although δ 15 N fractionation does not occur in the process of -N leaching, the effect on the whole soil δ 15 N composition is significant ( Corre et al, 2007 ). Microbial assimilation preferentially absorbs rather than due to the higher energy requirement in utilizing as an N source, except when the supply of is insufficient ( Choi, Matushima & Ro, 2011 ). Thus, the application of N fertilizer alters the original soil N cycling patterns, as well as the δ 15 N composition of different N pools ( Choi et al, 2017 ).…”