Nitrous oxide emissions from fertilized upland fields in Thailand

Nitrous oxide (N2O) emission from fertilized maize fields was measured usin g a closed chamber at four experimental sites in Thailand. The average meas ured N2O flux from unfertilized plots through crop season was 4.16 +/- 1.52 , 5.05 +/- 1.65, 5.25 +/- 1.68 and 6.74 +/- 2.95 mu g N2O-N m(-2) h(-1), at Nakhon Sawan, Phra Phutthabat, Khon Kaen and Chiang Mai, respectively. Inc reased N2O emissions by the application of nitrogen fertilizer were 0.22-0. 44, 0.19-0.38%, 0.12-0.24 and 0.08-0.15% of the applied N, respectively. Co mpared to other data, N2O emission rate to applied nitrogen was not signifi cantly different between the data of Thailand and the Temperate Zone.