Zhang Cui-Jing, Shen Ju-Pei, Sun Yi-Fei, Wang Jun-Tao, Zhang Li-Mei, Yang Zhong-Ling, Han Hong-Yan, Wan Shi-Qiang, He Ji-Zheng
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
FEMS Microbiol Ecol. 2017 Apr 1;93(4). doi: 10.1093/femsec/fix037.
Global climate change could have profound effects on belowground microbial communities and subsequently affect soil biogeochemical processes. The interactive effects of multiple co-occurring climate change factors on microbially mediated processes are not well understood. A four-factorial field experiment with elevated CO2, watering, nitrogen (N) addition and night warming was conducted in a temperate steppe of northern China. Real-time polymerase chain reaction and terminal-restriction fragment length polymorphism, combined with clone library techniques, were applied to examine the effects of those climate change factors on N-related microbial abundance and community composition. Only the abundance of ammonia-oxidizing bacteria significantly increased by nitrogen addition and decreased by watering. The interactions of watering × warming on the bacterial amoA community and warming × nitrogen addition on the nosZ community were found. Redundancy analysis indicated that the ammonia-oxidizing archaeal community was affected by total N and total carbon, while the community of bacterial amoA and nosZ were significantly affected by soil pH. According to a structural equation modeling analysis, climate change influenced net primary production indirectly by altering microbial abundance and activities. These results indicated that microbial responses to the combination of chronic global change tend to be smaller than expected from single-factor global change manipulations.
全球气候变化可能对地下微生物群落产生深远影响，进而影响土壤生物地球化学过程。多种同时发生的气候变化因素对微生物介导过程的交互作用尚未得到充分理解。在中国北方温带草原进行了一项包含二氧化碳浓度升高、浇水、添加氮（N）和夜间增温的四因素田间试验。应用实时聚合酶链反应和末端限制性片段长度多态性，并结合克隆文库技术，来研究这些气候变化因素对与氮相关的微生物丰度和群落组成的影响。仅添加氮显著增加了氨氧化细菌的丰度，而浇水则使其降低。发现了浇水×增温对细菌氨单加氧酶基因（amoA）群落的交互作用以及增温×添加氮对一氧化二氮还原酶基因（nosZ）群落的交互作用。冗余分析表明，氨氧化古菌群落受总氮和总碳的影响，而细菌amoA和nosZ群落则受土壤pH的显著影响。根据结构方程模型分析，气候变化通过改变微生物丰度和活性间接影响净初级生产力。这些结果表明，微生物对长期全球变化组合的响应往往小于单因素全球变化操纵预期的响应。
