不同干耕措施下紫云英还田水稻土中DOM组成特征与CH_(4)排放的关联  

Association Between Association Between DOM Composition Characteristics and CH4 Emission of Chinese Milk Vetch Amended Under Different Water Management

作　　者：刘晗 马停停 万里 陈晓芬 周国朋 孙晋鑫 朱安繁 李燕丽 刘佳[1] LIU Han;MA Ting-ting;WAN Li;CHEN Xiao-fen;ZHOU Guo-peng;SUN Jin-xin;ZHU An-fan;LI Yan-li;LIU Jia(Soil and Fertilizer&Resources and Environment Institute,Jiangxi Academy of Agricultural Sciences,National Engineering&Technology Research Center for Red Soil Improvement,Key Laboratory of Acidified Soil Amelioration and Utilization,Ministry of Agriculture and Rural Affairs,Nanchang 330200,China;College of Agriculture,Yangtze University,Jingzhou 434025,China;State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China,Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China;Agricultural Technology Promotion Center of Jiangxi Province,Nanchang 330046,China)

机构地区：[1]江西省农业科学院土壤肥料与资源环境研究所,国家红壤改良工程技术研究中心,农业农村部酸化土改良与利用重点实验室,江西南昌330200 [2]长江大学农学院,湖北荆州434025 [3]中国农业科学院农业资源与农业区划研究所/北方干旱半干旱耕地高效利用全国重点实验室,北京100081 [4]江西省农业技术推广中心,江西南昌330046

出　　处：《光谱学与光谱分析》2024年第12期3435-3442,共8页Spectroscopy and Spectral Analysis

基　　金：国家重点研发计划项目(2021YFD1700203);国家自然科学基金项目(42267046,32202609,32160766);财政部和农业农村部:国家现代农业产业技术体系(CARS-22)资助。

摘　　要：为研究不同水分管理下(先干耕再复水)紫云英还田水稻土中可溶性有机质(DOM)组成结构与甲烷(CH_(4))排放量之间的关系,采用室内培养法,以不添加绿肥(紫云英)不干耕(DW-0)为对照,设置不同水分管理处理(不干耕、干耕5 d、干耕10 d),运用三维荧光光谱(3DEEM)和平行因子分析(PARAFAC)评估土壤DOM组成、荧光光谱对CH_(4)排放的影响。结果表明,添加紫云英干耕5 d(G+DW-5)处理下DOM含量与CH_(4)累计排放量均显著降低;随着干耕时间延长,DOM含量与CH_(4)累计排放量都呈上升趋势。通过3DEEM-PARAFAC法得到三种荧光组分,包括类富里酸(C1)、类腐殖酸(C2)、类蛋白质(C3),且不同水分管理措施下土壤DOM荧光组分组成存在明显差异。G+DW-5处理下土壤DOM中类腐殖质组分(C1+C2)含量最高,占比可达79.88%;限制性主成分分析表明,不同水分管理下土壤DOM组分分异明显。G+DW-5处理下DOM腐殖化指数(HIX)为5.11,显著高于其他水分处理。相关性分析表明,CH_(4)排放量与C1组分、HIX指数显著负相关,而与C2组分、自生源指数(BIX)显著正相关,说明短期干耕可通过增加C1组分含量及土壤DOM腐质化程度来降低CH_(4)排放。不同水分管理措施下紫云英还田水稻土DOM组成和结构特征与CH_(4)排放量密切相关,可为稻田减排提供科学依据。In order to study the relationship between the composition and structure of dissolved organic matter(DOM)and methane(CH_(4))emissions in the paddy soil with Chinese milk vetch returning under different water managements(flooding after a short time delay),we set an incubation experiment,with no green manure and no tillage(DW-0)as control,different water management treatments(immediately flooding,flooding after 5 and 10 days)were set up,three-dimensional fluorescence spectroscopy(3DEEM)and parallel factor analysis(PARAFAC)were used to assess the effects of soil DOM composition and the effect of fluorescence spectra on CH_(4) emissions.The results showed that both DOM content and cumulative CH_(4) emissions significantly decreased under G+DW-5 treatment,and both DOM content and cumulative CH_(4) emissions increased with the extension of dry tillage time.Three fluorescence components,including fulvic-like(C1),humic-like(C2),and protein-like(C3),were obtained by the 3DEEM-PARAFAC method.There were significant differences in the fluorescence components of soil DOM under different water management practices.The highest content of humus-like components(C1+C2)was found in soil DOM under the G+DW-5 treatment,which reached 79.88%,and the restricted principal component analysis indicated that soil DOM components were significantly different under different water management.The DOM Humification Index(HIX)of G+DW-5 was 5.11,significantly higher than other treatments.The correlation analysis showed that CH_(4) emissions were negatively correlated with the C1 and HIX index but positively correlated with the C2 and BIX index;the results showed that flooding after a short time delay could reduce CH_(4) emissions by increasing the content of C1 and the level of soil DOM humification.Overall,the composition and structure of DOM in the paddy soil under different water managements are closely related to CH_(4) emissions,which could provide a scientific basis for reducing CH_(4) emissions from paddy soil.

关 键 词：绿肥 干耕 甲烷 可溶性有机质 三维荧光光谱 平行因子分析 

分 类 号：S142[农业科学—肥料学]