土壤硝化和反硝化微生物群落及活性对大气CO_2浓度和温度升高的响应  

Response of Soil Nitrifier and Denitrifier Community and Activity to Elevated Atmospheric CO_2 Concentration and Temperature

作　　者：刘远[1] 王光利[1] 李恋卿[2] 潘根兴[2] LIU Yuan WANG Guang-li LI Lian-qing PAN Gen-xing(College of Life Science, Huaibei Normal University, Huaibei 235000, China College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China)

机构地区：[1]淮北师范大学生命科学学院,淮北235000 [2]南京农业大学资源与环境科学学院,南京210095

出　　处：《环境科学》2017年第3期1245-1252,共8页Environmental Science

基　　金：国家自然科学基金项目(41501304;31100083);农业部公益性行业(农业)科研专项(200903003)

摘　　要：硝化和反硝化微生物参与土壤氮循环转化过程,大气CO_2浓度和温度升高可能会影响它们的群落结构和活性.本试验依托稻-麦轮作农田系统气候变化平台研究大气CO_2浓度单独升高(CE)、升温(WA)以及两者同时升高(CW)对麦田土壤硝化和反硝化微生物基因丰度、群落结构和活性的影响.结果表明,在小麦分蘖期,大气CO_2浓度和温度升高对氨氧化细菌(AOB)和反硝化细菌丰度没有影响,而在抽穗和成熟期,CO_2浓度单独升高显著提高了氨氧化古菌(AOA)和反硝化细菌丰度,升温处理对其没有显著影响.通过对T-RFLP数据分析发现,大气CO_2浓度和温度升高对土壤AOA、AOB和反硝化细菌群落结构没有显著影响,但是在一定程度上改变了AOA和反硝化细菌多样性.另外,CO_2浓度单独升高处理显著提高了成熟期的土壤硝化速率,不同气候变化处理对反硝化速率没有显著影响.研究表明大气CO_2浓度和温度升高对不同生育期的微生物群落影响存在差异,而且功能微生物对不同气候变化因子处理的响应也各不相同.Elevated atmospheric CO2 concentration and temperature may affect nitrifiers and denitrifiers which are related to soil N turnover. A climate change experiment was conducted in the rice-wheat rotation ecosystem. This study was used to investigate effects of elevated CO2 and temperature on soil microbial community structure,as well as abundance and activity of nitrifiers and denitrifiers. The results showed that no change in the abundance of ammonia-oxidizing bacteria（ AOB） and denitrifier was observed at the tillering stage,however at the later stages,elevated CO2 alone significantly increased the abundance of ammonia-oxidizing archaea（ AOA） and denitrifier but there were no changes under CW treatment. The analysis of T-RFLP profiles showed that elevated CO2 and temperature had no obvious effect on community structure of AOA,AOB or denitrifier,but altered diversity index（ H＇） of AOA and denitrifier.Moreover,elevated CO2 alone significantly increased nitrifying rate at the ripening stage. Elevated CO2 and temperature did not result in significant change in denitrifying rate at each single stage. These results suggested that effects of elevated CO2 and temperature on microbial community were different among the tillering, heading and ripening stages, and functional microorganism responded differently to multiple climate change treatments.

关 键 词：CO2浓度升高 温度升高 冬小麦 氨氧化细菌 氨氧化古菌 

分 类 号：X171[环境科学与工程—环境科学]