油菜-水稻复种系统一次性施肥对CH_4和N_2O净排放的影响  

The Impacts of CH_4 and N_2O Net Emission Under One-Off Fertilization of Rape-Paddy Replanting System

作　　者：徐驰 谢海宽 丁武汉 戴震 张婧[1] 王立刚[1] 李虎[1] XU Chi;XIE HaiKuan;DING WuHan;DAI Zhen;ZHANG Jing;WANG LiGang;LI Hu(Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences/Key Laboratory of Agricultural Non-point Source Pollution Control,Ministry of Agriculture/Joint Research Laboratory for Sustainable Agro-ecosystem Research between Chinese Academy of Agricultural Sciences and University of New Hampshire(CAAS-UNH),Beijing 100081)

机构地区：[1]中国农业科学院农业资源与农业区划研究所/农业部面源污染控制重点实验室/中国农业科学院-美国新罕布什尔大学可持续农业生态系统研究联合实验室,北京100081

出　　处：《中国农业科学》2018年第20期3972-3984,共13页Scientia Agricultura Sinica

基　　金：国家重点研发计划(2016YFE010110;2016YFD0201204;2018YFD0800402);国家自然科学基金(41671303);中央级公益性科研院所基本科研业务费(1610132016042);国家公益性行业(农业)科研专项(201303103)

摘　　要：【目的】探究一次性施肥技术对油菜-水稻复种系统CH_4和N_2O排放及其特征的影响并分析其影响因素,综合计算全球增温潜势,以期了解一次性施肥技术对温室气体排放的贡献大小,从而为温室气体减排提供科学依据和技术参考。【方法】针对长江中下游地区典型的油菜-水稻复种模式,在荆州太湖港农场(30.36N,112.08E)油菜-水稻复种试验田设置了5个处理:对照处理(CK)、农民习惯施肥处理(FP)、优化施肥处理(OPT)、一次性尿素基施处理(UA)和一次性控释肥基施处理(CRF),重复3次。采用静态暗箱-气相色谱法对整个油菜-水稻季的CH_4和N_2O排放通量进行监测,并测定土壤种植前后的理化性质与作物产量。【结果】(1)N_2O和CH_4的排放均具有明显的水稻季排放高、油菜季排放低的季节动态变化规律。各处理N_2O排放通量在油菜季的变化范围为-4.08—35.51μg N·m^(-2)·h^(-1),水稻季则为-16.52—193.30μg N·m^(-2)·h^(-1),年平均排放通量3.66—23.70μg N·m^(-2)·h^(-1);各处理CH_4的通量变化在油菜季的排放量为-0.08—0.05 mg C·m^(-2)·h^(-1),水稻季则为-0.54—4.81 mg C·m^(-2)·h^(-1),年平均排放通量0.42—0.66 mg C·m^(-2)·h^(-1);(2)N_2O年排放总量从高到低依次是FP、CRF、OPT、UA、CK,分别为1.31、1.19、1.04、0.82、0.37 kg N·hm^(-2),排放系数介于0.14%—0.25%,均低于IPCC的推荐值1%。两个一次性施肥处理的UA和CRF相比同等施氮量的OPT处理,均能有效减少CH_4年排放量29.0%和29.9%, UA处理同时能减少21.2%的N_2O年排放总量,而CRF处理却增加了14.8%的N_2O年排放总量;(3)在同等施氮量的条件下,一次性施肥CRF比OPT显著增加油菜产量10.6%,而对水稻产量的影响不显著。温室气体排放强度呈现油菜季低,而水稻季高的特征,油菜和水稻季中各处理差异均不显著,油菜季中CRF和UA的排放强度最低为0.038 kgCO_(2-eq)·kg^(-1),OPT最高为0.057kgCO_(2-eq)·kg^(-1),�【Objective】The objective of this paper was to explore the impacts of one-off fertilization on CH4 and N2O emissions and its impacting factors in rape-paddy replanting system to calculate global warming potential,and to understand the contribution of one-off fertilization to the greenhouse gas emission,so as to provide scientific basis and technical reference for greenhouse gas emission reduction.【Method】Based on the typical rape-paddy replanting system in the middle and lower reaches of the Yangtze River,the experiments were set up in the(30.36N,112.08E)rape-paddy replanting test field in Taihu port farm of Jingzhou from October 2015 to September 2016 with 5 treatments,including Control treatment(CK),Farmers'Practice treatment(FP),Optimal fertilizer treatment(OPT),Urea fertilizer treatment(UA)and Controlled release fertilizer treatment(CRF),with 3 replicates.In the whole growth period,the static chamber gas chromatography method was used for determination of CH4 and N2O emission flux.Before and after planting,the physicochemical properties of soil and yield of the crop were measured.【Result】(1)The emissions of N2O and CH4 had obvious seasonal dynamics of high in paddy season and low in rape season.The fluxes of N2O varied-4.08-35.51μg N·m^-2·h^-1 and varied-16.52-193.30μg N·m^-2·h^-1 in the paddy season.The average annual emission flux varied 3.66-23.70μg N·m^-2·h^-1;the fluxes of CH4 varied-0.08-0.05 mg C·m^-2·h^-1 in rape season.The fluxes of CH4 in rice season varied-0.54-4.81 mg C·m^-2·h^-1.The annual average flux varied 0.42-0.66 mg C·m^-2·h^-1.(2)The amounts of N2O emissions from high to low were FP,CRF,OPT,UA,and CK,respectively,and the value of them was 1.31,1.19,1.04,0.82 and 0.37 kg N·hm^-2,respectively.The emission factors were a range in 0.14%-0.25%,all values were lower than 1%,which were IPCC Recommended.Compared with OPT treatment with the same amount of nitrogen input,the two one-off fertilization UA and CRF treatments could effectively reduce CH4 emissions by 29.0%and

关 键 词：一次性施肥 油菜-水稻复种系统 温室气体 全球增温潜势 

分 类 号：S511[农业科学—作物学] S565.4