等氮替代施入生物炭对南方免耕早稻田温室气体排放的影响  

Effect of Isonitrogen Substitution for Biochar Application on Greenhouse Gas Emissions from Southern No-till Early Rice Fields

作　　者：李诗 张俊辉[1] 胡钧铭[1] 周凤珏[2] 李婷婷[1] 徐美花 马洁萍 陆展彩 LI Shi;ZHANG Jun-hui;HU Jun-ming;ZHOU Feng-jue;LI Ting-ting;XU Mei-hua;MA Jie-ping;LU Zhan-cai(Agricultural Resource and Environment Research Institute,Guangxi Academy of Agricultural Sciencess/Guangxi Key Laboratory of Arable Land Conservation,Nanning 530007,China;Agricultural College,Guangxi University,Nanning 530004)

机构地区：[1]广西农业科学院农业资源与环境研究所/广西耕地保育重点实验室,南宁530007 [2]广西大学农学院,南宁530004

出　　处：《中国农业气象》2023年第10期863-875,共13页Chinese Journal of Agrometeorology

基　　金：国家自然科学基金项目(41661074);广西“新世纪十百千人才工程”专项资金(2018221);广西科技基地和人才专项(2022AC18008);广西农业科学院创新团队项目(桂农科2021YT040)。

摘　　要：生物炭是新型外源有机底物,其稳定性好,吸附性强,富含碳营养物,常作为固碳减排的重要有机资源。中国南方早籼稻产量高,雨热同期且种植制度独特,2021-2022年试验在典型籼稻区南宁开展,共设置3种处理分别为,对照处理(CK):不施肥;无机氮投入(T1,化肥)处理:化肥施用量为常规施肥水平,复合肥800kg·hm^(-2),尿素260.87kg·hm^(-2),钾肥193.55kg·hm^(-2);无机氮配施有机氮(T2,生物炭+化肥)处理:生物炭4000kg·hm^(-2),复合肥738.67kg·hm^(-2),尿素146.09kg·hm^(-2),钾肥34.19kg·hm^(-2)。本研究在水稻插秧5d后,采用分离式静态箱-气相色谱法,定期监测水稻生育期内稻田土壤温室气体排放,解析其温室气体累计排放量、排放当量及水稻产量性状,探讨等氮替代施入生物炭对南方早稻田温室气体排放、水稻产量的影响,为优化集约化早籼稻低碳种植和减肥增效提供依据。结果表明:(1)生物炭能降低稻田土壤CH_(4)、CO_(2)排放,通过减缓CH_(4)排放而减小综合排放当量。化肥配施生物炭可减缓单施化肥引起的温室气体碳源增排效应,其减缓CO_(2)排放的延后效应较明显,生物炭处理(T2)中,与化肥处理(T1)相比,2021年CH_(4)最大排放通量降低41.38%,累计排放量降低31.25%,2022年最大排放通量降低50.50%,累计排放量显著降低50%,2a的综合排放当量显著低于T1处理;2021年CO_(2)最大排放通量、累计排放量分别比T1处理减小57.38%和37.68%,2022年比T1处理分别相应减小16.06%和35.52%。(2)生物炭可抑制N_(2)O排放,显著降低累计排放量,减小氮源排放当量。与T1处理对比,T2处理2021年N_(2)O最大排放通量减小5.43%,而累计排放量显著降低33.53%;2022最大排放通量减小73.75%,累计排放量显著降低54.33%。(3)生物炭利于集约化早籼稻种植结构优化,提升早籼稻生产力。生物炭投入稻田2a后,增产效果明显,T2处理的理论产量为T1处理的1.02~1.33倍,实际产量则Biochar has been recognized as a new exogenous organic substrate and is often used as an important organic resource for carbon reduction because of its stability,adsorption and carbon nutrient richness.The study was conducted in a typical indica rice area of Nanning from 2021 to 2022,against the background of having high early indica rice yields,simultaneous rain and heat,and unique cropping system.In this paper,authors set three treatments:Control treatment(CK):no fertilizer.Inorganic N input(T1,chemical fertilizer) treatment:chemical fertilizer application at conventional fertilizer level,compound fertilizer 800kg·ha^(-1),urea 260.87kg·ha^(-1),potassium 193.55kg·ha^(-1).Inorganic N with organic N(T2,biochar + chemical fertilizer) treatment:biochar 4000kg·ha^(-1),compound fertilizer 738.67kg·ha^(-1),urea 146.09kg·ha^(-1),potassium 34.19kg·ha^(-1).The cumulative greenhouse gas emissions,emission equivalents,rice yield traits and the effect of isonitrogen substitution of biochar application on greenhouse gas emissions and rice yield in early southern rice fields were analyzed by regular monitoring of soil greenhouse gas emissions in rice fields during the rice reproductive period using a split static box-meteorological chromatography method 5d after rice transplanting,this study provide a basis for optimizing intensive early rice low-carbon cultivation and reduce fertilizer and increase efficiency.The results showed that:(1) biochar can reduce CH_(4) and CO_(2) emissions from paddy soils,and reduce the combined emission equivalent by slowing down CH_(4) emissions.The application of fertilizer with biochar can mitigate the increase of greenhouse gas carbon emissions caused by fertilizer application alone,and its delayed effect of mitigating CO_(2) emissions is more obvious.In biochar treatment(T2),compared with the chemical fertilizer treatment(T1),the maximum CH_(4) emission flux in 2021 was reduced by 41.38% and the cumulative emission was reduced by 31.25%,and the maximum emission flux in 2022 was reduced

关 键 词：温室气体 生物炭 低碳优化 集约化稻田 早籼稻 

分 类 号：S511[农业科学—作物学]