Chiba Akane, Uchida Yoshitaka, Kublik Susanne, Vestergaard Gisle, Buegger Franz, Schloter Michael, Schulz Stefanie
Research Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan.
Research Unit Comparative Microbiome Analysis, Helmholtz Zentrum München, German Research Centre for Environmental Health, 85764 Neuherberg, Germany.
Microorganisms. 2021 Feb 11;9(2):357. doi: 10.3390/microorganisms9020357.
This study aimed to investigate the effects of different levels of soil- and plant-associated bacterial diversity on the rates of litter decomposition, and bacterial community dynamics during its early phases. We performed an incubation experiment where soil bacterial diversity (but not abundance) was manipulated by autoclaving and reinoculation. Natural or autoclaved maize leaves were applied to the soils and incubated for 6 weeks. Bacterial diversity was assessed before and during litter decomposition using 16S rRNA gene metabarcoding. We found a positive correlation between litter decomposition rates and soil bacterial diversity. The soil with the highest bacterial diversity was dominated by oligotrophic bacteria including Acidobacteria, , and , and its community composition did not change during the incubation. In the less diverse soils, those taxa were absent but were replaced by copiotrophic bacteria, such as and , until the end of the incubation period. SourceTracker analysis revealed that litter-associated bacteria, such as , only became part of the bacterial communities in the less diverse soils. This suggests a pivotal role of oligotrophic bacteria during the early phases of litter decomposition and the predominance of copiotrophic bacteria at low diversity.
本研究旨在调查不同水平的土壤和植物相关细菌多样性对凋落物分解速率的影响，以及在其早期阶段细菌群落的动态变化。我们进行了一项培养实验，通过高压灭菌和重新接种来控制土壤细菌多样性（而非丰度）。将天然或经高压灭菌的玉米叶施用于土壤，并培养6周。在凋落物分解之前和期间，使用16S rRNA基因宏条形码技术评估细菌多样性。我们发现凋落物分解速率与土壤细菌多样性之间存在正相关。细菌多样性最高的土壤以贫营养细菌为主，包括酸杆菌属、 和 ，其群落组成在培养期间没有变化。在多样性较低的土壤中，这些类群不存在，但被富营养细菌如 和 取代，直到培养期结束。SourceTracker分析表明，与凋落物相关的细菌，如 ，仅在多样性较低的土壤中成为细菌群落的一部分。这表明贫营养细菌在凋落物分解早期阶段起关键作用，而富营养细菌在低多样性时占主导地位。
