@article{Metivier:253330,
      recid = {253330},
      author = {Metivier, Leann and Whalen, Joann and Gouveia, Gregory},
      title = {NITROUS OXIDE PRODUCTION IN TROPICAL SOILS UNDER DIFFERENT  MOISTURE REGIMES AND N-APPLICATION RATES},
      address = {2014},
      number = {538-2016-38619},
      pages = {13},
      year = {2014},
      abstract = {Nitrous oxide (N2O) is a potent trace gas responsible for  approximately 6% of the current greenhouse gas (GHG) effect  with 60 to 80% of total global emissions originating from  the agricultural sector.  Within this sector, the majority  of N2O emissions come from soils arising mainly from N  fertilizer additions. In the Caribbean, no studies have  been conducted to quantify the N2O flux from our soils,  although this information is crucial in gaining a better  understanding of how to manage N fertilizers, such as urea,  to minimize N2O fluxes.  In our region, urea represents  approximately 80% of N-fertilizer used.   In this  laboratory study, the effects of ureaN rate and soil  moisture on N2O, CH4 and CO2 flux were investigated on  three soils from Trinidad. The18 treatment combinations  were arranged in a completely randomized design with four  replicates (72 experimental units).  The equivalent of 220  g oven dried soil were placed in 1L mason jars and  incubated at 50% Water Filled Pore Space (WFPS) for 7 days.  Then, urea-N solutions of 0, 75 and 150 kg N/ha were  applied and the soil moisture was further adjusted to 60%  and 90% WFPS. Jars were then sealed and headspace air was  sampled using a syringe via a rubber septum on the lid at  regular intervals: three times on day 1 and then once per  day for the next two weeks. Gas samples were injected into  evacuated exetainers and analyzed for N2O, CO2 and CH4  concentrations using a gas chromatograph equipped with a  Flame Ionization Detector (FID) and an Electron Capture  Detector (ECD). Increases in N-fertilizer application rate  did not have a significant effect on N2O production however  it must be noted that N2O emissions were greater as  N-applicate rate increased. Soil moisture was significant  to N2O production with highest emissions under 90% WFPS  compared to 60%WFPS.   Soil type also had a significant  effect with the greatest emission from the Nariva peaty  clay soil type.  The N2O flux data presented in this paper  is the first report for Trinidad soils. This study has  implications for improving urea-N fertilizer use  efficiency, which could enhance soil productivity while  minimizing environmental pollution.},
      url = {http://ageconsearch.umn.edu/record/253330},
      doi = {https://doi.org/10.22004/ag.econ.253330},
}