Controlled release fertilizer product effects on potato crop response and nitrous oxide emissions under rain-fed production on a medium-textured soil

Abstract

R. 2012. Controlled release fertilizer product effects on potato crop response and nitrous oxide emissions under rain-fed production on a medium-textured soil. Can. J. Soil Sci. 92: 759Á769. Controlled release fertilizers and split fertilizer N applications are expected to provide plant-available nitrogen (N) in synchrony with crop requirements, which should mitigate nitrous oxide (N 2 O) emissions from agricultural soils. This study compared a polymer coated urea (PCU) controlled release N fertilizer (Environmentally Smart Nitrogen), split fertilizer N application and conventional fertilizer N management on the crop response and growing season N 2 O emissions from rain-fed potato (Solanum tuberosum L.) production on a medium-textured soil in Atlantic Canada from 2008 to 2010. Fertilizer were applied at the recommended rate (193 kg N ha (1 ) and treatments included the PCU product banded at planting, conventional fertilizer in a split application (60% as diammonium phosphate plus ammonium nitrate at planting plus 40% as ammonium nitrate at final hilling), conventional fertilizer (diammonium phosphate plus ammonium nitrate) banded at planting, and an unfertilized control. Within each year, cumulative growing season N 2 O emissions were closely related to soil nitrate availability as measured by nitrate exposure (sum of daily nitrate concentration in the surface soil). Split N application had no effect on crop response, and significantly reduced nitrate exposure, but did not reduce N 2 O emissions. With the PCU, there was evidence of increased plant N availability and greater N 2 O emissions. In situations where the risk of nitrate leaching is limited, substitution of a PCU product for conventional fertilizer at the same N application rate will not necessarily reduce growing season N 2 O emissions and may in some cases increase the risk of N 2 O emissions. Further research is required to determine if lowering N rates with PCU products will be effective agronomically and environmentally. . et Dowbenko, R. 2012. Incidence des engrais a`libe´ration lente sur le rendement de la pomme de terre et sur les e´missions d'oxyde nitreux dans les sols non irrigue´s de granulome´trie moyenne. Can. J. Soil Sci. 92: 759Á769. L'application d'engrais a`libe´ration lente ou leur application fractionne´e devrait procurer aux plantes suffisamment d'azote (N) assimilable, en synchronisme avec les besoins de la culture, ce qui devrait re´duire les e´missions d'oxyde nitreux (N 2 O) des sols agricoles. La pre´sente e´tude compare l'incidence des engrais N a`libe´ration lente ab ase d'ure´e enrobe´e de polyme`re (PCU), aussi appele´s azote e´cologique, de l'application fractionne´e d'engrais N et des pratiques courantes d'amendement sur la re´action de la culture et sur les e´missions saisonnie`res de N 2 O pour la pomme de terre (Solanum tuberosum L.) cultive´e sans irrigation sur un sol de texture moyenne, dans les provinces de l'Atlantique, de 2008 a`2010. L'engrais a e´te´applique´au taux recommande´(193 kg de N par hectare) et les t...

Nitrous oxide emission and fertiliser nitrogen efficiency in a tropical sugarcane cropping system applied with different formulations of urea

“…However, the delayed release of N from PCU was not translated into lower or higher N 2 O emissions compared with the conventional urea treatments, again demonstrating that N 2 O emission rates were not sensitive to variation in mineral N contents in this specific cropping system. Zebarth et al (2012) also found no significant difference in annual cumulative N 2 O emissions between PCU and conventional fertiliser. Polymer-coated urea would more likely reduce N 2 O emissions if applied at a lower rate, without causing a loss in crop yield.…”

Effect of polymer-coated urea on nitrous oxide emission in zero-till and conventionally tilled silage corn

“…In both years it was apparent that emissions with CRU were higher than urea about a month after application, and this is consistent with a previous study on Vancouver Island, British Columbia, where weather patterns are similar to this study (Jassal et al 2008). There have been other reports of delayed N 2 O emissions with application of CRU compared with urea, but this effect is not consistent across years and locations, although CRU frequently affects the magnitude of the emission peaks (Drury et al 2012;Li et al 2012;Zebarth et al 2012 …”

“…For example, Gagnon et al (2012) reported that grain corn yields were higher with PCU than with untreated urea in Quebec but the agronomic benefits of PCU were less consistent for small grain crops on the Canadian prairies, silage corn (Zea mays L.) in British Columbia, or potatoes (Solanum tuberosum) in New Brunswick (Soon et al 2011;Grant et al 2012;Zebarth et al 2012). Hyatt et al (2010) reported higher potato yields and lower N 2 O emissions from PCU than from conventional urea on sandy soils in Minnesota.…”

Nitrous Oxide Emissions from a Clay Soil Receiving Granular Urea Formulations and Dairy Manure

“…Li et al (2012) recently showed that polymer-coated urea reduced N 2 O emissions compared with conventional urea. Other studies, however, found more N 2 O emissions from polymer-coated than from conventional urea (Sistani et al, 2011;Jiang et al, 2010;Zebarth et al, 2012) and that the effectiveness of stabilizers varied with soil properties (Kelliher et al, 2008), highlighting uncertainty in the effectiveness of enhanced-efficiency N fertilizer products to mitigate emissions. Nitrate intensity, sometimes referred as nitrate exposure, was introduced by Zebarth et al (2008aZebarth et al ( , 2008b and Burton et al (2008aBurton et al ( , 2008b as an assessment of the magnitude and duration of soil NO 3 -and its potential impact on soil biology and the potential for NO 3 -loss to the environment.…”