Field experiment was conducted in farmer’s rice field with loamy soil in Khon Kaen province, northeast of Thailand during to study the effect of different levels of sulfate (SO42-) on methane emission and rice yield. SO42- was applied at the rate of 0, 50, 100, and 210 kg SO42- ha-1 by using ammonium phosphate (42% SO42-) with balanced amount of 80 kg N, 100 kg P2O5 and 80 kg K2O ha-1 by adding various fertilizers. The experiment was laid out in randomized completely block design (RCBD) with tripled replication. CH4 flux was measured every week by using closed chambers method. Global warming potential (GWP) was also calculated. Soil samples were collage at each growth stage to determine SO42-, NH4+ and Fe2+. Rice yield was measured at harvest. The... |