Abstract:

Abstract: Diurnal variation of soil respiration affected by long-term different fertilization at various growth stages of wheat in red soil dry-land was investigated with the static dark chamber method and gas chromatograph technique at the Experimental station of red soil CAAS. Results show that the different soil fertility and crop growth under long-term different fertilization is an important factor to effect the soil CO2, N2O emissions. During the growth stages of wheat, soil respiration rate displayed an obvious seasonal curve. CO2, N2O emission fluxes in different experimental treatments had significant differences Cumulative emissions of CO2 and N2O in the year varying in the range of 8284.02 kg?ha-1～15863.48 kg?ha-1 and 0.37 kg?ha-1～2.04 kg?ha-1. In terms of the effect of fertilization, the CO2 emissions followed an order of 1.5NPKM>NPKM>NPK>CK>NP, and N2O emissions followed an order of 1.5NPKM>NPKM>NPK>NP>CK, The treatment with organic manure increase in CO2 and N2O emissions significantly (p < 0.05) than the others. The change of CO2 emissions was obviously related to soil temperature, but the change of N2O emissions was obviously related to soil water content.