Influence of Enhanced UV-B Radiation on Respiration Rate and N2O Emission from Soil-Winter Wheat System
地表UV-B辐射增强对土壤-冬小麦系统呼吸速率和N2O排放的影响

To investigate the impact of enhanced UV-B radiation on respiration rate and N2O emission from soil-winter wheat system, outdoor pot experiments with simulating 20% supplemental of UV-B were conducted, and static dark chamber\|gas chromatograph method were used. Results indicated that the enhanced UV-B radiation did not change the seasonal pattern of respiration rate and N2O emission. Enhanced UV-B radiation declined the rate of soil-winter wheat system's respiration but had no significant impact on N2O emission in turning-green stage. While enhanced UV-B radiation declined both respiration rate and the N2O emission in elongation-pregnant stage. From heading to maturity, the respiration rate and N2O emission from soil-winter wheat system were not found to be significantly difference under UV-B radiation compared with ambient conditions. A further analysis suggested that enhanced UV-B radiation declined significantly cumulative amount of N2O from soil-winter wheat system from wheat turning green to full heading stage, while no significant impact occurred from full heading to maturity.