生物炭处理下干湿交替灌溉稻田活性氮气体排放特性  

Reactive gaseous N losses from an alternate wetting and drying paddy field as affected by biochar application

作　　者：祝宏远 陈涛涛[1,2,3] 张琬婷 于建明 迟道才 孟军[2,3] ZHU Hongyuan;CHEN Taotao;ZHANG Wanting;YU Jianming;CHI Daocai;MENG Jun(College of Water Resources,Shenyang Agricultural University,Shenyang 110866,China;National Biochar Research Institute,Shenyang Agricultural University,Shenyang 110866,China;Key Laboratory of Biochar and Soil Improvement,Ministry of Agriculture and Rural Affairs,Shenyang,110866,China;Research Institute of Water Resources and Hydropower,Shenyang 110003,China)

机构地区：[1]沈阳农业大学水利学院,沈阳110866 [2]沈阳农业大学国家生物炭研究院,沈阳110866 [3]农业农村部生物炭与土壤改良重点实验室,沈阳110866 [4]辽宁省水利水电科学研究院有限责任公司,沈阳110003

出　　处：《农业工程学报》2023年第15期76-85,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：辽宁省应用基础研究计划项目青年专项(2023030237-JH2/1016);中国博士后科学基金面上项目(2019M661129)。

摘　　要：干湿交替灌溉具有节水稳产等优势,但也存在促进NH_(3)挥发和增加N_(2)O排放的风险。而生物炭具有改善土壤、蓄水保肥、降低温室气体排放等诸多正效应。为探究干湿交替灌溉条件下稻田活性氮气体排放(主要为NH_(3)和N_(2)O)对添加生物炭的响应机制,设置不同灌溉模式(淹灌和干湿交替灌溉)和生物炭用量(0和20 t/hm^(2))2个因素4个处理,通过2020和2021年大田原位试验,对稻田土壤环境、NH3挥发、N_(2)O排放、植物氮素吸收和产量等进行了研究。结果表明,2 a间,干湿交替灌溉对水稻产量均未产生显著影响(P>0.05),但却显著增加了NH3挥发(仅2020年)和N_(2)O排放(P<0.05),增幅分别达到8.9%和105.0%~115.0%;而添加生物炭显著降低了NH_(3)挥发(8.7%~20.5%)和N_(2)O排放(21.6%~24.2%)(P<0.05),减少9.0%~20.6%的活性氮气体排放(P<0.05)。较之无炭常规淹灌对照处理,干湿交替灌溉结合生物炭处理,可在实现增产0.2%~12.5%的同时,降低活性氮气体排放6.1%~11.7%。干湿交替灌溉促进N_(2)O排放的主要原因是频繁灌水-落干条件下稻田土壤NO_(3)^(−)-N浓度和氧化还原电位均得到了显著提升;而生物炭增产降氨的主要原因是无机氮固持量得到了显著提升,进而降低了NH3挥发损失,增加了水稻氮素吸收,最终实现增产。研究揭示了生物炭在干湿交替稻田的应用潜力,为实现稻田节水增产,增汇减排及降低活性氮排放带来的环境代价提供理论依据。Alternate wetting and drying irrigation(IAWD)is one types of water-saving technologies to repeatedly dry and reflood the fields.However,the frequent alternate aerobic and anaerobic environment under IAWD has increased the reactive nitrogen gases emission in rice fields.Fortunately,biochar has been widely used to improve the land productivity(including the crop production,carbon sequestration,mitigation of GHG,and remediation of heavy metal pollution)in the agricultural soil amendment.However,little information is available on the effects of biochar on the NH_(3)volatilization,N_(2)O emissions,and reactive nitrogen gas emissions in paddy rice systems,especially under IAWD.This study aims to explore the response mechanism of reactive nitrogen gas emissions to the biochar application under IAWD conditions.A two-year field split-plot experiment was conducted with the biochar application rates(0 and 20 t/hm^(2))under two irrigation regimes(continuously flooded irrigation,ICF and IAWD).Two irrigation regimes were used as the main plots,whereas,two biochar additions were the subplots.Each plot was in the size of 3 m(width)×6 m(length)that separated by the PVC barrier at a depth of 30 cm.in order to avoid the lateral flow of nutrients and water.The results showed that the IAWD increased yields by 1.7%to 5.1%(P>0.05),NH_(3)volatilization 8.9%(only in 2020),and N_(2)O emissions by 105.0%to 115.0%,compared with the ICF(P<0.05).Biochar addition at the rate of 20 t/hm^(2)was significantly reduced the NH3 volatilization by 8.7%to 20.5%and N_(2)O emissions by 21.6%to 24.2%(P<0.05).There was an increase in the yield by 0.2%to 12.5%and a reduction in the reactive nitrogen gas emissions by 6.1%to 11.7%in biochar combined with the IAWD,compared with the control(ICFB0).Furthermore,the inorganic nitrogen existed mainly in the form of NH_(4)^(+)-N in the soil environment of rice field,accounting for 88.6%to 94.7%.The IAWD had no significant some impact on the soil NH_(4)^(+)-N,compared with the ICF,whereas,the significant increase wa

关 键 词：水稻 生物炭 NH3挥发 N2O排放 活性氮排放 干湿交替灌溉 

分 类 号：S511[农业科学—作物学] S154.1