Abstract:Laboratory work had been conducted to evaluate NO2- and NO3- accumulation capacity in the process of nitrification in 9 Chinese agricultural soils, and to investigate stability of NO2- in the 9 soils. Dynamic procedure was also done to observe the duration of NO2- in 3 soils of different properties and locations at the same NH4+ levels. Results showed that acid and fine-textured soils, Red earth and Yellow-brown earth, had no NO2- accumulation at all NH4+ levels, while alkaline or calcareous soils, such as Sajiang black soil, Fluvo-aquic soil, Coastal solonchaks, Cinnamon soil, Irrigated desert soil, and Sierozem had significant NO3-accumulation. NO2- accumulation in each soil of pH>7 increased with the elevation of NH4+ levels. NO2- in 2 acid soils was independent of the NH4+ levels, but in the other 7 soils inhibited by high NH4+ input. It was found that NO2- was unstable in acid soils, but durable in alkaline soils or even in neutral soils. The results obtained in the study showed that NO2- accumulation in the process of nitrification in soils with pH more than 7 should attract more attention.