易利用态有机物质对水稻土甲烷排放的激发作用  

Priming Effects of Labile Organic Substances on Methane Emission in Flooded Paddy Soil

作　　者：邱虎森[1,2,3] 苏以荣 刘杰云[1] 葛体达[1,2] 胡亚军[1,2] 陈香碧[1,2] 吴金水[1,2] 张振华[4] QIU Husen;SU Yirong;LIU Jieyun;GE Tida;HU Yajun;CHEN Xiangbi;WU Jinshui;ZHANG Zhenhua(Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China;Changsha Research Station for Agricultural ＆ Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China;University of Chinese Academy of Sciences, Beij＇ing 100049, China;Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha 410128, China)

机构地区：[1]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,长沙410125 [2]中国科学院长沙农业环境观测研究站,长沙410125 [3]中国科学院大学,北京100049 [4]湖南农业大学南方粮油作物协同创新中心,长沙410125

出　　处：《土壤》2018年第3期537-542,共6页Soils

基　　金：国家自然科学基金项目(41430860;41471199);中国科学院战略性先导科技专项项目(XDB15020401)资助

摘　　要：为探讨外源有机物质对淹水稻田土壤CH4排放的激发作用,对比不同外源有机物质对土壤CH4排放的贡献差别,本研究选取3种标记的易利用态有机物(葡萄糖、乙酸和草酸)分别加入水稻土,进行了为期1个月的培养。结果表明:培养30 d后不同处理CH4的累计排放量差异显著(P<0.05),其中,乙酸>葡萄糖>草酸>对照;双因素方差分析结果显示,外源有机物质的添加加速了土壤易利用态有机质的矿化(即产生正激发效应);不同处理条件下激发作用产生的CH4分别占各处理CH4总累计排放量的73.3%(葡萄糖处理)、71.5%(乙酸处理)和40.9%(草酸处理),且CH4排放量与CH4激发效应之间极显著正相关关系说明土壤CH4排放主要要来自于土壤原有机质的分解,外源有机物质可能主要对土壤微生物活性及代谢途径有影响。In order to clarify the priming effect and contribution of exogenous organic matter on CH4 emissions, an incubation experiment was carried out with three ^13C-labeled organic substances （glucose, acetic acid, and oxalic acid） in a paddy soil for one month. The results showed that cumulative CH4 emissions were significantly different among different treatments, in an order of acetic acid 〉 glucose 〉 oxalic acid 〉 control （P〈0.05）. Two-way ANOVA indicated that the decomposition of soil native organic matter was accelerated with the addition of exogenous organic matter （positive priming effect）. The percentages of priming effect （PE） CH4 from soil were about 73.3% （glucose）, 71.5% （acetic acid） and 40.9% （oxalic acid） of total CH4, respectively. Different PEs and the significantly positive correlations between CH4 production and PE demonstrated that exogenous organic matter can promote soil CH4 emission, mainly because of their PE on original soil organic matter. The major role of exogenous organic matter on soil native organic matter decomposition may be due to their effects on soil microbial activity metabolism.

关 键 词：甲烷 有机质 稳定性同位素 激发效应 

分 类 号：S154.1[农业科学—土壤学]