中文摘要：

采用人工模拟UV-B增强方式,通过大田试验,研究了UV-B增强与秸秆施用对土壤-大豆系统呼吸速率和N2O排放通量的影响.结果表明：在三叶-分枝期、开花-结荚期、鼓粒成熟期和全生长期,UV-B增强,系统平均呼吸速率分别降低了59.88%,65.47%,67.35%和64.44%,N2O平均排放通量分别降低了37.94%,24.61%,48.42%和34.16%;秸秆施用促进了系统呼吸速率,4个时期平均呼吸速率分别增加了59.88%,61.50%,99.16%和64.44%;降低了全生长期的N2O平均排放通量,但没有达到显著差异水平（P=0.236）.UV-B增强和秸秆施用复合处理显著增大土壤-大豆系统的呼吸速率,降低全生长期的N2O平均排放通量,但没有达到显著差异水平（P=0.229）.

英文摘要：

To investigate the combined influence of enhanced UV-B radiation and straw addition on respiration rate and N2O emission from soybean ecosystem,field experiments were carried out during soybean growing season. Enhanced UV-B radiation significantly declined mean respiration rate （MRR） and mean N2O flux （MNF）. During the trefoil-branching stage,flowering-podding stage,filling-ripening stage and whole growth stage,MRR were declined by 59.88%,65.47%,67.35% and 64.44%,respectively,MNF were decreased by 37.94%,24.61%,48.42% and 34.16%,respectively. Straw addition （S） had a positive effect on respiration rate,which increased by 59.88%,61.50%,99.16% and 64.44% in above 4 stages. Though S treatment declined MNF of whole growth stage,there was no significant difference between S and the control （C） （P=0.236）. Combined treatment of straw addition and enhanced UV-B radiation （SU） significantly accelerated the reapiration rate,declined MNF of whole growth stage,but there was no significant difference in MNF between SU and C （P=0.229）.