摘要
土壤氮循环是构成全球生物化学循环的关键组成部分,其中氨氧化微生物介导的硝化作用是驱动氮循环的重要动力.为了解不同海拔梯度森林土壤氨氧化微生物的空间分布规律,采用qPCR技术,以参与编码的氨单加氧酶(amoA)为标记,调查各海拔梯度(1 800-4 100 m)贡嘎山森林土壤氨氧化细菌(Ammonia oxidizing bacteria,AOB)和氨氧化古菌(Ammonia oxidizing archaea,AOA)的数量,并揭示其与环境因子的相关性.结果表明,不同海拔梯度森林表层土壤中均具有一定数量的AOA和AOB,且在低海拔地区(1 800-3 200 m)均高于高海拔地区(3 600-4 100 m).AOA数量在海拔较低地区变化趋势为0.04%-5.63%,垂向尺度上最高降低10.7%;AOB数量在不同海拔之间均存在显著差异,3 800 m较1 800 m高出22.5%. Spearman相关分析表明,不同海拔梯度氨氧化微生物数量对环境变化的响应模式不同,AOB与气候(年均温度、年均降水量)、pH、土壤温度、碳氮含量及电导率相关,而AOA变化仅与气候(年均温度、年均降水量)和土壤温度相关,与其他土壤因素不相关.本研究揭示出贡嘎山不同海拔梯度气候和土壤性质的综合作用可能是引起AOA和AOB数量及丰度变化的因子,且AOA和AOB数量具有极强的空间异质性;结果可为进一步研究大尺度森林生态系统氮循环相关微生物的海拔分布格局提供数据支撑.(图2表2参30)
The soil nitrogen cycle is a key component of the global biochemical cycle, of which the microorganism-mediated ammonia oxidation is an important driving force. However, the spatial distribution of forest soil ammonia-oxidizing microorganisms along elevation gradients has yet to be clarified. In this study, the abundance of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in the forest soil of Mount Gongga was investigated. The effect of environmental factors was analyzed using the qPCR technique with the encoded ammonia monooxygenase (amoA) as a marker. The results showed that there was a variable quantity of AOA and AOB in the surface soil of different altitude gradient forests, and the abundance in the low altitude area (1 800-3 200 m) was higher than in the high altitude area (3 600-4 100 m). The abundance of AOA in the lower altitude areas ranged from 0.04%-5.63%, with a peak of 10.7% on the vertical scale. The abundance of AOB varied significantly with different altitudes, and was 22.5% higher at 3 800 m than at 3 600 m. Spearman correlation analyses showed that the response patterns of ammoxidation microbial abundance to environmental changes were different in different elevation gradients. AOB are affected by climate (annual average temperature, average annual precipitation), pH, soil temperature, carbon and nitrogen content, and electrical conductivity, while AOA are only affected by climate (annual average temperature, annual precipitation) and soil temperatures. The comprehensive effects of the climate and soil properties at various altitudes may be the factor that leads abundance differences in AOA and AOB. This study revealed that the ammonia-oxidizing microorganisms at different altitude gradients on Mount Gongga have a strong spatial heterogeneity and are significantly affected by environmental factors. This can provide data support for a further in-depth study of the distribution pattern of nitrogen cycle-related microorganisms in a large-scale forest ecosystem.
作者
王晓胡
寇涌苹
赵文强
严贤春
WANG Xiaohu;KOU Yongping;ZHAO Wenqiang;YAN Xianchun(College of Life Science, China West Normal University, Nancong 637002, China;CAS Key Laboratory Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2019年第2期275-280,共6页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学青年基金项目(31500445)
中国科学院"西部之光"项目(Y7K2031101)
西华师范大学英才科研基金项目(17YC353)资助~~
关键词
氨氧化微生物
基因丰度
分布特征
海拔梯度
贡嘎山
环境因子
ammonia-oxidizing microorganism
gene abundance
distribution pattern
elevation gradient
Gongga Mountain
environmental factor
