地表UV-B辐射增强对土壤-冬小麦系统呼吸速率和N_2O排放的影响  

Influence of Enhanced UV-B Radiation on Respiration Rate and N_2O Emission from Soil-Winter Wheat System

作　　者：胡正华[1] 蒋静艳[1] 牛传坡[1] 孙文娟[2] 黄耀[1] 

机构地区：[1]南京农业大学资源与环境科学学院 [2]中国科学院大气物理研究所,北京100029

出　　处：《环境科学》2007年第3期449-454,共6页Environmental Science

基　　金：国家自然科学基金项目(40605029);中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室开放课题项目(LAPC-KF-2004-03);南京信息工程大学科研基金项目(Y410)

摘　　要：通过室外盆栽实验,用静态箱-气相色谱法测定土壤-冬小麦系统的呼吸速率和N2O排放通量,研究了UV-B辐射增强20%对土壤-冬小麦系统的呼吸速率和N2O排放的影响.结果表明,相同的气象条件和田间管理下,UV-B辐射增强处理对呼吸速率和N2O排放的季节变化模式无明显影响.在返青期,UV-B辐射增强显著降低了土壤-冬小麦系统的呼吸速率,但对N2O的排放通量没有产生显著影响;在拔节孕穗期,UV-B辐射增强处理显著降低了土壤-冬小麦系统的呼吸速率和N2O的排放通量;在抽穗-成熟期,UV-B辐射增强处理对土壤-冬小麦系统的呼吸速率和N2O的排放没有显著影响.返青-齐穗期,UV-B增强处理显著降低土壤-冬小麦系统的N2O累积排放量;但从齐穗开始至小麦成熟,UV-B增强处理对土壤-冬小麦系统的N2O累积排放量没有显著影响.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-R 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.

关 键 词：UV-B辐射 土壤-冬小麦系统 呼吸速率 N2O排放 

分 类 号：X511[环境科学与工程—环境工程]