Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Microb Ecol. 2018 Nov;76(4):1041-1052. doi: 10.1007/s00248-018-1183-3. Epub 2018 Apr 11.
Understanding how microorganisms respond to environmental disturbance is one of the key focuses in microbial ecology. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are responsible for ammonia oxidation which is a crucial step in the nitrogen cycle. Although the physiology, distribution, and activity of AOA and AOB in soil have been extensively investigated, their recovery from a natural disturbance remains largely unknown. To assess the recovery capacities, including resistance and resilience, of AOA and AOB, soil samples were taken from a reservoir riparian zone which experienced periodically water flooding. The samples were classified into three groups (flooding, recovery, and control) for a high-throughput sequencing and quantitative PCR analysis. We used a relative quantitative index of both the resistance (RS) and resilience (RL) to assess the variation of gene abundance, alpha-diversity, and community composition. The AOA generally demonstrated a better recovery capability after the flooding disturbance compared to AOB. In particular, AOA were more resilient after the flooding disturbance. Taxa within the AOA and AOB showed different RS and RL values, with the most abundant taxa showing in general the highest RS indices. Soil NH and Fe/Fe were the main variables controlling the key taxa of AOA and AOB and probably influenced the resistance and resilience properties of AOA and AOB communities. The distinct mechanisms of AOA and AOB in maintaining community stability against the flooding disturbance might be linked to the different life-history strategies: the AOA community was more likely to represent r-strategists in contrast to the AOB community following a K-life strategy. Our results indicated that the AOA may play a vital role in ammonia oxidation in a fluctuating habitat and contribute to the stability of riparian ecosystem.
了解微生物如何响应环境干扰是微生物生态学的重点之一。氨氧化细菌（AOB）和古菌（AOA）负责氨氧化，这是氮循环中的关键步骤。尽管已经广泛研究了土壤中 AOA 和 AOB 的生理学、分布和活性，但它们从自然干扰中的恢复情况在很大程度上仍不清楚。为了评估 AOA 和 AOB 的恢复能力，包括抵抗力和恢复力，从经历周期性水淹的水库河岸带采集土壤样本。将样本分为三组（水淹、恢复和对照）进行高通量测序和定量 PCR 分析。我们使用抵抗（RS）和恢复力（RL）的相对定量指数来评估基因丰度、α多样性和群落组成的变化。与 AOB 相比，AOA 在水淹干扰后通常表现出更好的恢复能力。特别是，AOA 在水淹干扰后更具恢复力。AOA 和 AOB 中的分类群表现出不同的 RS 和 RL 值，最丰富的分类群通常表现出最高的 RS 指数。土壤 NH 和 Fe/Fe 是控制 AOA 和 AOB 关键分类群的主要变量，可能影响 AOA 和 AOB 群落的抵抗力和恢复力特性。AOA 和 AOB 维持群落稳定性以应对水淹干扰的不同机制可能与不同的生活史策略有关：与遵循 K 生活策略的 AOB 群落相比，AOA 群落更可能代表 r 策略者。我们的结果表明，AOA 可能在波动生境中的氨氧化中发挥重要作用，并有助于河岸带生态系统的稳定性。
