【Objective】Nitrous oxide (N₂O) is an important greenhouse gas contributing to global warming and depleting stratospheric ozone. Agricultural soils are the major sources of anthropogenic N₂O emissions. N₂O emitted from natural and cultivated soils is mainly generated through nitrification and denitrification, accounting for about 70% of the global total, but contributions of other processes (such as chemodenitrification) are poorly understood. Hydroxylamine (NH₂OH) and nitrite (NO₂⁻-N) are two main intermediate products of nitrification, and the latter is also an intermediate product of denitrification, both of which can produce N₂O through abiotic processes. However, relative contributions of these two products to N₂O emission in the same soil remain unclear. 【Method】To determine contributions of the two products, NH₂OH and NO₂⁻-N, through abiotic processes in soil to emission of N₂O and to identify related affecting factors, an indoor incubation experiment was designed and carried out, using soil samples collected from a tea garden in Quzhou, an upland field in Yingtan, a vegetable garden in Changshu, an upland field in Hailun, an orchard in Changshu and an upland field in Fengqiu, representing four types of land use. The soil samples, sterilized (autoclaved three times at 121℃ for 1 h before nitrogen fertilization) and unsterilized, were spiked with NH₂OH or NO₂^--N, separately, and incubated. Emissions of N₂O from the soil samples were monitored after 2 hours of incubation. 【Result】Addition of NH₂OH or NO₂^--N increased N₂O emission from each tested soil, with N₂O flux peaking 2 h after the addition of NH₂OH during the observed period, and the highest peak was observed from the soil samples collected from the orchard in Changshu Orchard (1 585 μg kg⁻¹ h⁻¹). N₂O emissions from the soils spiked with NO₂⁻-N varied in the range of 6.42~61.28 μg kg⁻¹ h⁻¹ in flux. In unsterilized or natural soil samples spiked with NH₂OH, N₂O emission coefficients varied from 18.63% to 35.95%, which were 10.03 times~76.46 times that in the soil samples spiked with NO₂^--N. Effect of sterilization on N₂O emission differed between the soil samples spiked with NH₂OH and their respective ones spiked with N₂O⁻-N. Sterilization significantly reduced N₂O emission in all the soil samples spiked with NH2OH, especially in the soil samples from the tea garden in Quzhou, with the reduction reaching, up to 94%, while in the soil samples spiked with NO₂⁻-N, the effect of sterilization was observed only in those from Changshu and Fengqiu, but reverse effects were found in those from Quzhou, Yingtan, Changshu and Hailun. In all the soil samples, abiotic processes of NH₂OH contributed 6%~73% to total of N₂O emission, whereas abiotic process of NO₂⁻-N did 3%~236%. In the soil samples from Quzhou, Yingtan, Changshu and Hailun, all being higher than 7 in pH, abiotic process of NO₂⁻-Ncontributed more than abiotic process of NH₂OH did to N₂O emission but in the soil samples from Changshu and Fengqiu, both being higher than 7 in pH too, reverse trends were found, indicating soil pH is a key factor affecting abiotic N₂O production from NH₂OH or NO₂⁻-N. In the soil samples spiked with NH2OH, the contribution of abiotic process, in terms of proportion, to the total N₂O emission was significantly and positively related to soil pH (p< 0.05), while in the soil samples spiked with NO₂⁻-N, it was negatively related (p< 0.01). 【Conclusion】All the above-describedfindings suggest that the formation of N₂O from NO₂⁻-N is probably mainly attributed to abiotic processes in acid soils and to biotic processes in alkaline soils, while the formation of N₂O from NH₂OH goes just the opposite.