Nitrous oxide is one of main greenhouse gases and with 200 times warmming potential comparing with carbon dioxide.Nitrogen fertilizer inputs in particular have been identified as the main source of N2O emissions from agricultural soils.Trends in fertilizer N use suggest this affect will continue into the future.Much of the recent growth in world N fertilizer consumption occurred in developing countries.Nitrogen fertlizer types, use rates and placements had a different influence on nitrous oxide emission.Lab experment and field study also show that the main reason for the N2O fluxes increae is nitrite accumulation in the soil during the nitrification process.Urea nest placement and high does inhibited nitrite oxides and result in more nitrite in soil and higher nitrous oxide emission.