摘要
【目的】研究不同灌水量下冬小麦农田土壤N2O和CO2的排放特征及影响因子,为制定科学的农田灌溉策略和温室气体减排方案提供理论依据。【方法】选择河北省晋州市长期玉米-小麦轮作农田土壤作为研究对象,设置CK(89.96 mm)、T1(80.96 mm)、T2(71.97 mm)、T3(62.97 mm)、T4(53.98 mm)、T5(44.98 mm)6种灌溉水量处理,采用静态暗箱-气相色谱法采集和分析了冬小麦全生育期内土壤N2O和CO2的排放通量。【结果】①灌水量的减少降低了土壤N2O和CO2的排放通量,与CK相比,T1—T5处理土壤N2O累积排放量分别减少24.99%(P=0.18)、10.89%(P=0.53)、39.14%(P=0.06)、48.99%(P<0.05)和56.11%(P<0.05);土壤CO2累积排放量分别减少5.47%、4.75%、9.65%、7.52%和12.33%,但均未达到显著水平(P>0.05);②N2O排放通量与0~10、10~20 cm土壤孔隙度含水率(WFPS)和0~5 cm土壤温度正相关,CO2排放通量与0~10 cm土壤WFPS和0~5 cm土壤温度正相关,与10~20 cm土壤WFPS负相关。③与CK相比T1—T5处理,土壤N2O和CO2的综合排放温室效应减少了5.70%~19.08%,T3处理小麦产量最高。【结论】综合考虑气体排放和小麦产量,T3处理对应的灌水量是兼顾节水、作物产量和温室气体减排的推荐灌溉水量。
【Background】Global warming instigated by anthropological activities is the greatest environmental concern faced by the world,in which emission of N2O and CO2 from soil plays an important part.【Objective】The overarching objective of this paper is to understand the mechanisms underlying the emissions of N2O and CO2 from winter wheat field under different irrigations in attempts to provide guidance on improving agronomical management and consequently reducing greenhouse gas emissions.【Method】The experiment was conducted in a maize-wheat rotation field at Jinzhou city,Hebei province;it consists of six irrigation treatments:89.96 mm(CK),80.96 mm(T1),71.97 mm(T2),62.97 mm(T3),53.98 mm(T4)and 44.98 mm(T5).In each treatment,we measured and analyzed the emission flux of N2O and CO2 using the static chamber-gas chromatography.【Result】①The emission of N2O and CO2 increased with irrigating water.Compared with CK,T1 to T5 reduced the cumulative emission of N2O by 24.99%(P=0.18),10.89%(P=0.53),39.14%(P=0.06),48.99%(P<0.05)and 56.11%(P<0.05)respectively,while reduced the CO2 emission by 5.47%,4.75%,9.65%,7.52%and 12.33%,respectively,although not at significant level(P>0.05).②Correlation analysis showed that N2O emission was positively correlated with moisture in the 0~20 cm soil and temperature in the 0~5 cm soil.In contrast,CO2 emission was positively correlated with moisture in the 0~10 cm soil and temperature in the 0~5 cm soil,and negatively correlated with moisture in the 10~20 cm soil.③Compared with CK,T1—T5 reduced the combined greenhouse effect of N2O and CO2 emission by 5.70%~19.08%,and T3 gave the highest wheat yield.【Conclusion】Irrigating 62.97 mm of water is optimal in terms of water use efficiency,crop yield and reducing greenhouse gases emission in the studied area.
作者
熊浩
张保成
李建柱
张旭
石建华
XIONG Hao;ZHANG Baocheng;LI Jianzhu;ZHANG Xu;SHI Jianhua(Tianjin University School of Civil Engineering,Tianjin 300350,China;Beijing Sino-water Keyuan Engineering Consulting Co.,Ltd.,Beijing 100053,China)
出处
《灌溉排水学报》
CSCD
北大核心
2020年第9期41-50,共10页
Journal of Irrigation and Drainage
基金
全球环境基金水资源与水环境综合管理推广(主流化)项目(P145897)。
