不同冬季覆盖作物对稻田CH_4和CO_2排放的影响  

Effects of winter cover crop on methane and carbon dioxide emissions from paddy field

作　　者：周艳飞[1] 刘念[1] 刘章勇[1] 金涛[1] ZHOU Yanfei;LIU Nian;LIU Zhangyong;JING Tao(Engineering Research Center of Ecology and Agricultural Use of Wetland China Ministry of Education,Yangtze University,Jingzhou 434025,China)

机构地区：[1]长江大学湿地生态与农业利用教育部工程研究中心,荆州434025

出　　处：《生态科学》2018年第5期94-101,共8页Ecological Science

基　　金：国家自然科学基金(31501274);湖北省高等学校优秀中青年科技创新团队项目(T201404);湖北省重大科技创新计划(2016AHB023)

摘　　要：冬季稻田排放的甲烷(CH_4)和二氧化碳(CO_2)是影响稻田温室气体排放的重要因素。为探求种植适宜的冬季覆盖作物并减少稻田冬季CH_4和CO_2排放,试验采用静态暗箱法对播种油菜的稻田(YC)、播种小麦的稻田(XM)及冬闲田(CK)三个处理下稻田的CH_4和CO_2排放进行了观测,分析了不同冬季覆盖作物对稻田CH_4和CO_2的排放影响。结果表明,不同处理CH_4排放通量为YC>XM>CK,CO_2排放通量为XM>YC>CK。不同冬季作物覆盖下,各处理CH_4和CO_2的累计排放量表现同其平均排放通量相同。YC处理的CH_4累计排放量与冬闲田(CK)处理的相比较达到显著水平(p<0.05), XM处理CO_2的累计排放量与YC和CK相比都有显著性差异(p<0.05)。根据稻田CH_4和CO_2季节排放量以及在100年尺度上的CO_2当量计算,不同处理温室气体全球增温潜势(GWP)大小顺序为XM>YC>CK,在YC、XM和CK中,小麦(Triticum aestivum L.)处理的增温潜势最大,且最大值达到6442.58 (kg·hm^(–2))。小麦处理的CO_2和CH_4的总温室效应最大,机耕直播油菜(Brassica napus L.)次之,冬闲田最小。研究水稻(Oryza sativa L.)收获后稻田种植不同冬季作物,观察在其生长季节内CH_4和CO_2和的排放特征,为合理利用冬闲稻田控制温室效应提供理论依据。Methane(CH4)and carbon dioxide(CO2)emissions from winter paddy fields are believed to produce great influence on greenhouses gas emissions from paddy field.Thus,it is necessary to explore suitable winter cover crops for reducing CH4 and CO2 emissions from paddy filed.Static chamber technique was employed to observe CH4 and CO2 emissions under three different treatments(tillage and directly sowing rape,YC;tillage and directly sowing winter wheat,XM;fallow was set as control,CK).Effects of different winter cover crops on emissions of CH4 and CO2 from paddy filed were analyzed during growth period.The results showed that CH4 emission flux decreased in order of YC>XM>CK;instead,CO2 emission flux decreased in order of XM>YC>CK.At the same time,cumulative emissions of CH4 and CO2 were observed keeping at the same decreased trends with their emission flux,respectively.CH4 emission in YC treatments was significantly higher than that in CK(P<0.05),However,CO2 cumulative emission in YC treatment was significantly lower than XM and CK(P<0.05).Global warming potential(GWP)(Calculated as the CO2-equivalents on the scale over 100 years)from CH4 and CO2 emissions in different treatments was decreased in order of XM>YC>CK;XM treatment had the largest GWP,with a value of 6442.58(kg·hm^–2).Abovementioned results revealed that XM treatment had the largest total greenhouse effect;however,CK treatment had lowest total greenhouse effect when compared with XM and YC treatment.Object of this study is to seek a reasonable using way for winter paddy field,and expect to provide theoretical basis for effective control of greenhouse gas emissions from paddy field.

关 键 词：油菜 冬稻田 冬小麦 温室气体 

分 类 号：S181[农业科学—农业基础科学]