开放式空气CO_2增高对稻田CH_4和N_2O排放的影响

Effects of elevated atmospheric CO_2 on CH_4 and N_2O emissions from paddy fields.

在FACE(free aircarbondioxideenrichment)平台上 ,采用静态暗箱 气相色谱法观测研究了大气CO2 浓度增加对稻田CH4和N2 O排放的影响 .结果表明 ,在 15 0和 2 5 0kgN·hm-2 两种氮肥水平下大气CO2 浓度增加 2 0 0 μmol·mol-1均明显促进水稻生长 ,水稻生物量积累 .大气CO2 浓度增加对 15 0和 2 5 0kgN·hm-2 两种氮肥水平下稻田CH4排放均无显著影响 ,并简要分析了与现有文献报道结果不一致的原因 .大气CO2 浓度增加也未导致 15 0和 2 5 0kgN·hm-2 两种氮肥水平下稻田N2 O排放的明显变化 ,与大多数研究结果一致 .

Effects of elevated atmospheric CO 2 on CH 4 and N 2O emissions during the paddy rice-growing season were examined in a FACE (free-air carbon dioxide enrichment) study. The emission fluxes of CH 4 and N 2O from paddy rice fields were measured using methods based on static opaque-chamber and gas chromatography techniques. Synthetic fertilizer N was amended for the rice-growing season at two rates, 150 and 250kgN·hm~ -2 and the atmospheric CO 2 was enriched by 200μmol·mol~ -1. At both N levels, the preliminary results indicate that no significant effect of CO 2 enrichment on CH 4 and N 2O emissions from the rice paddy fields was detected. The result on CH 4 emissions is inconsistent with the most literatures, and the result on N 2O emissions is consistent with the most literatures.