Differential Responses of Ammonia-oxidizers Communities to Nitrogen and Water Addition in Stipa baicalensis Steppe,Inner Mongolia,Northern China  

氮素和水分添加对贝加尔针茅草原土壤氨氧化微生物群落结构的影响（英文）

作　　者：王杰[1] 李刚[1] 赖欣[1] 宋晓龙[1] 赵建宁[1] 杨殿林[1] 

机构地区：[1]农业部环境保护科研监测所,天津300191

出　　处：《Journal of Resources and Ecology》2015年第1期1-11,共11页资源与生态学报（英文版）

基　　金：National Natural Science Foundation of China(31170435,31000242)

摘　　要：Atmospheric nitrogen deposition and precipitation as an important phenomenon of global climate change have a great impact on grassland ecosystems. However, little is known about how the soil ammonia-oxidizing microorganisms respond to the both changes. Ammonia oxidization is a crucial step in the soil nitrification and greatly inlfuenced by soil nitrogen availability. We used PCR and DGGE （denaturing gradient gel electrophoresis） approaches to investigate the responses of AOB （ammonia-oxidizing bacteria） 16S rRNA and AOA （ammonia-oxidizing archaea）amoA genes to nitrogen and water input inStipa baicalensis steppe, Inner Mongolia, northern China. After two years of nitrogen and water addition treatment, it was found that PNA （potential nitriifcation activity） was greatly enhanced by lower N fertilization treatment under water addition and higher N fertilization under no-water addition, while it decreased markedly in higher N fertilization under water addition. The community structure of AOB responded more sensitively to N fertilization and water input than AOA, resulting in the significantly decreased diversity in the AOB community along with a higher N fertilizer rate, but an obvious increase in the AOA community, demonstrating the active growth of AOA in higher N fertilization soils. Phylogenetic analysis showed that AOB communities were dominated byNitrosospira clusters3, 4 andNitrososmonas clusters 6 under water addition andNitrosospira culsters 1, 3 and 4 and under no-water addition, while AOA communities were grouped intoCrenarchaeote clusters 1, 2 and 5 under no-water addition and Crenarchaeote clusters 1, 2 and water lineage under water addition. The differences between the two water addition regimes strongly suggest that water input acts as an important role in shifting AOA and AOB communities. Moreover, in contrast to the AOA, the diversity of AOB was negatively correlated with total N, NH4^＋, NO3^- and pH under water addition, implying a signiifcant N fertilization and water effect on s应用PCR-DGGE技术研究了连续2年氮素、水分添加处理对贝加尔针茅草原土壤氨氧化细菌(AOB)16S r RNA基因和古菌(AOA)amo A基因遗传多样性的影响。结果表明,土壤硝化势在水分添加低氮(N30)和非水分添加高氮(N300)处理下较对照显著升高(P<0.05),在水分添加高氮(N200、N300)处理下较对照急剧下降(P<0.05)。不同处理下氨氧化细菌的群落结构变化较氨氧化古菌敏感,氮素添加显著改变了氨氧化微生物的群落结构,在高氮素处理下,氨氧化细菌的多样性指数有下降的趋势,而古菌的多样性则有升高的趋势,表明氨氧化古菌在高氮素下生长比较活跃。发育树分析的结果表明,非水分添加处理下,氨氧化细菌的群落由亚硝化螺菌属的Cluster 1、Cluster 3和Cluster 4组成,水分添加处理下由亚硝化螺菌属Cluster 3、Cluster 4和亚硝化单胞菌属的Cluster 6组成,而氨氧化古菌群落在水分添加处理下主要由泉古菌门的Cluster 1、Cluster 2和water lineage组成,在非水分添加处理下主要由泉古菌门的Cluster 1、Cluster 2和Cluster 5组成,两种水分输入机制下,氨氧化微生物群落的不同组成说明,水分在调节氨氧化微生物群落结构方面有重要作用。此外,氨氧化细菌群落多样性与全氮,NH4+和NO3-的含量呈显著负相关,而古菌群落与其呈显著正相关,说明氨氧化细菌与古菌对氮素和水分添加有不同的且互补的反应机制。

关 键 词：Stipa baicalensis steppe water addition N fertilization ammonia-oxidizing bacteria ammoniaoxidizing archaea DGGE community structure 

分 类 号：S812.2[农业科学—草业科学]