摘要
本研究以北京地区冬小麦-夏玉米轮作农田为研究对象,运用静态箱法针对不同施肥措施进行了1年CO2、N2O和CH4交换通量的连续观测.与对照区相比,施肥促进了CO2的排放,并且CO2排放通量表现为尿素区>硝态氮肥区;小麦季灌溉也引起了CO2排放的增加;此外,气温和地表温度是影响CO2排放的重要影响因素.冬小麦-夏玉米轮作过程中,N2O的排放集中在玉米季,温度成为小麦季N2O排放的限制因子.氮肥的施加极大地促进了N2O的排放,且等量氮素的硝态氮肥对N2O排放的促进作用明显小于尿素.土壤湿度的骤然变化也是引起N2O排放增加的一个重要因素.由多元线性回归模型分析知,pH、有机质、铵态氮、过氧化氢酶对N2O排放的贡献较大,是N2O排放的主要影响因子.施肥对所研究农田CH4交换通量没有显著影响,但研究区域的平均交换通量均为负值,表现为大气中CH4的一个汇.
The exchange fluxes of CO2, CH4 and N20 from a winter wheat-summer maize crop rotation farmland were investigated by static chamber method in Beijing area. They were all investigated during one wheat growing season and one maize growing season. Compared with the control plot, fertilizer application and cultivation evidently simulated CO2 emission. Higher CO2 emissions appeared in the urea plot than the nitrate fertilizer plot. Irrigation during wheat growing season also caused an increase in CO2 emission. Additionally, atmospheric temperature and soil surface temperature were important factors of CO2 emission. During the crop rotation process, N2O emission mostly occurred in the maize growing season and temperature became the limiting factor of N2O emission in the wheat growing season, N-fertilizer application greatly promoted N2O emission. Despite the same amount of nitrogen application, nitrate fertilizer plot emitted less N2O than urea plot. The sudden change of soil moisture also caused an increase in N2O emission. According to multiple linear regression analysis, pH, organic matter, ammonium, catalase contributed largely to N2O emission. Fertilizer application had no significant impact on CH4 fluxes, but the average exchange fluxes of the investigated plots were all negative values, indicating that the investigated soil was a sink of CH4.
出处
《环境化学》
CAS
CSCD
北大核心
2014年第4期591-596,共6页
Environmental Chemistry
基金
国家林业公益性行业科研项目(20130430104)
中央高校基本科研业务费专项(YX2011-14)
北京林业大学大学生创新创业训练项目(201210022078)
国家自然科学基金资助(51078034
51278051)资助
关键词
温室气体
施肥
影响因素
冬小麦-夏玉米轮作农田
北京地区
greenhouse gases, fertilizer, influencing factors, winter wheat-summer maize croprotation farmland, Beijing area.
