摘要
采用硅胶管法和微生物分子生态学方法对华北平原典型旱地土壤夏玉米根系密集区与行间土壤产生的N2O及与氨氧化细菌和反硝化细菌数量的关系进行了研究。结果表明:夏玉米三叶期和十叶期的施肥灌水措施以及超过15 mm左右的降雨均显著促进了土壤N2O的产生。夏玉米行间产生的N2O略高于根系密集区,但二者未达显著差异水平。相关分析表明,影响土壤N2O产生的主要环境因子为土壤空隙含水量(WFPS)及土壤NO-3-N含量,二者决定系数分别为0.79和0.51。N2O浓度与氨氧化细菌amoA基因拷贝数及反硝化细菌nirS基因拷贝数之间的显著正相关关系(决定系数分别达0.55和0.62)表明土壤中N2O的产生与氨氧化细菌和nirS基因反硝化细菌数量的增加有关。表明在该试验条件下,夏玉米根系生长对根系密集区土壤中氮和水的消耗以及氨氧化细菌和反硝化细菌数量的变化并未引起根系密集区和玉米行间N2O浓度的显著差异,即在田间布设N2O观测箱时,采样箱是否覆盖作物根系或采样箱覆盖作物根系的多少对N2O排放量的测定结果没有显著性影响。
The teria abundance N2O concentration in [ ammonia-oxidizing the root dense zone and the row of summer maize and the relationships with bacbacteria （AOB） and denitrifiers] were measured using silicon tube method and microbial molecular technology in a typical dry land agricultural soil in the North China Plain. The results showed that the great amount of N2O was produced after fertilization and irrigation measures and above 15 mm precipitation.N2O concentration in the row is higher than in root dense zone of summer maize slightly, but not reached significant difference. The correlation analysis showed that the significant positive relationship were observed between N2O concentration and water-filled porespace （WFPS） and the content of NO3 -N, the determination coefficient reached 0. 79 and 0. 51, respectively; and the significant positive relationship were observed between N2O concentration and the copy numbers of amoA and nirS also, the determination coefficient reached 0. 55 and 0. 62, respectively, it indicated that environment factors （WFPS and the content of NO3 -N） and the changes of AOB and denitrifiers abundance influenced N2O production significantly. In conclusion, in our experiment conditions, the consume of N and water due to maize root growth and the changes of AOB and denitrifiers in the root dense zone not caused N2O production significant difference between the root dense zone and row of summer maize. Thus, when we install the closed chamber in the field, whether included plant root or not have no significant influence to the results of N2O emission.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2011年第5期1156-1165,共10页
Journal of Plant Nutrition and Fertilizers
基金
公益性行业科研专项(201103039)
教育部博士点基金(20100008110004)资助
作者简介
保琼莉（1982-），女，青海乐都人，博士研究生，主要从事旱地农田N2O排放生物学机理方面的研究。E-mail：qionglibao@163．com
通信作者Tel：010—62732006，E-mail：juxt@cau．edu．cn
