巢湖圩区再生稻田甲烷及氧化亚氮的排放规律研究  

Reduced methane and nitrous oxide emissions from ratoon rice paddy in Chaohu polder area, China

作　　者：王天宇 樊迪 宋开付 张广斌[1] 徐华[1] 马静[1] WANG Tianyu;FAN Di;SONG Kaifu;ZHANG Guangbin;XU Hua;MA Jing(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]土壤与农业可持续发展国家重点实验室,中国科学院南京土壤研究所,南京210008 [2]中国科学院大学,北京100049

出　　处：《农业环境科学学报》2021年第8期1829-1838,共10页Journal of Agro-Environment Science

基　　金：国家重点研发计划项目(2017YFD0300105);国家自然科学基金项目(41877325,41671241);中国科学院青年创新促进会项目(2018349)。

摘　　要：为明确巢湖圩区再生稻田甲烷(CH_(4))及氧化亚氮(N_(2)O)的排放规律,采用静态箱-气相色谱法对比观测了巢湖圩区2019—2020年再生稻田(RR)和稻麦轮作田(SW)的CH_(4)和N_(2)O排放通量,测定了土壤氧化还原电位(Eh)、土壤溶解性有机碳(DOC)、土壤铵态氮(NH+_(4)-N)和硝态氮(NO-_(3)-N)。研究结果表明:SW处理在水稻返青期和分蘖期出现较大CH_(4)排放峰,RR处理的CH_(4)排放峰不仅出现在中稻季返青期和分蘖期,还出现在成熟期和再生季前期。SW处理N_(2)O排放峰主要出现在麦季降雨之后、稻季烤田及排水落干时,而RR处理N_(2)O排放峰主要出现在促苗肥施用后。与SW处理相比,RR处理的全年CH_(4)排放量、N_(2)O排放量、总温室气体排放量(TGHG)和温室气体排放强度(GHGI)分别降低了22.3%、86.5%、36.3%和15.9%(P<0.05)。RR处理无小麦产量,但水稻产量增加了16.2%(P<0.05)。稻季CH_(4)排放通量与土壤Eh呈显著负相关(P<0.01),但与土壤DOC含量无显著相关性(P>0.05)。RR处理的稻季N_(2)O排放通量与土壤NH_(4)^(+)-N浓度呈显著正相关(P<0.05)。综合来看,在巢湖圩区种植再生稻不仅能提高水稻产量,还大幅减少总温室气体排放量和温室气体排放强度。A field experiment was conducted from 2019 to 2020 to compare the differences in methane(CH_(4))and nitrous oxide(N_(2)O)emissions between ratoon rice(RR)fields and rice-wheat rotation(SW)fields in Chaohu polder using the static chamber-gas chromatograph technique.CH_(4) and N_(2)O fluxes from the RR and SW fields were observed,while the soil redox potential(Eh),soil dissolved organic carbon(DOC),soil ammonium(NH4+-N),and soil nitrate(NO_(3)--N)contents were determined during the rice-growing season.The study results revealed that larger CH_(4) flux peaks appeared in the SW treatment during the rice greening and tillering stages.However,CH_(4) flux peaks of the RR treatment appeared at the regreening and tilling stages in the main season,and at the ripening stage of the main season,and in the first half of the ratoon season.The N_(2)O flux peaks of the SW treatment primarily appeared after precipitation in the wheat season and during drainage periods,while N_(2)O flux peaks for the RR treatment mainly appeared after fertilizer application for bud promotion.Compared with SW,the annual total CH_(4) emissions,total N_(2)O emissions,total greenhouse gas emissions,and greenhouse gas emission intensities of RR were reduced by 22.3%,86.5%,36.3%,and 15.9%,respectively(P<0.05).No wheat grain was produced in the RR treatment,and rice yield increased by 16.2%(P<0.05).The seasonal variation in CH_(4) flux during the rice-growing season for each treatment was significantly negatively correlated with soil Eh(P<0.01),but no significant correlation was found between CH_(4) flux and soil DOC concentration(P>0.05).The seasonal variation of N_(2)O flux for RR treatment during the rice-growing season was significantly positively correlated with soil NH_(4)^(+)-N content(P<0.05).In conclusion,planting ratooning rice in the Chaohu polder area increases rice yield and dramatically reduces the comprehensive greenhouse effect and greenhouse gas emission intensity.

关 键 词：再生稻 稻麦轮作 温室气体排放 巢湖圩区 

分 类 号：X16[环境科学与工程—环境科学] S511[农业科学—作物学]