Wood decay is an important process in forest ecosystems, which relies on wood chemical properties and the action of a complex community of decomposers. While the important role of fungi in this process is recognized, our knowledge concerning the colonization of decaying wood by bacteria, their relative distribution as well as their potential functional roles remain under-investigated. In this context, our aim was to characterize how the bacterial communities are structured at both taxonomic and functional levels along the soil-wood continuum, using oak discs positioned on the forest floor for nine months. Using a combination of culture-dependent and -independent methods associated to a physical measure of wood decay, we evidenced that at the middle stage of decay investigated, the heartwood- and sapwood-inhabiting bacterial communities significantly differed from one another in term of richness and taxonomic composition, but also from those of the bulk soil. The functional screening revealed low metabolic potentials and a higher frequency of cellulose decomposing bacteria in wood than in the bulk soil, suggesting an adaptation of these communities to this habitat and to the physical-chemical conditions occurring in decaying wood. Together, our data evidence that the colonization of decaying wood by bacteria is based on a deterministic process linking extrinsic and intrinsic factors.

木材腐烂是森林生态系统中的一个重要过程，它依赖于木材的化学特性和复杂的分解者群落的作用。尽管人们认识到了真菌在该过程中的重要作用，但是我们对细菌在腐烂的木材上定植，其相对分布以及它们潜在的功能作用的知识仍未得到充分研究。在这种情况下，我们的目的是利用放置在森林地面上九个月的橡树圆盘，表征沿土壤-木材连续体的细菌群落在分类和功能水平上的结构。通过结合依赖文化的方法和独立于木材腐烂的物理测量方法，我们证明了在腐烂的中间阶段，居住在心材和边材上的细菌群落在丰富度和生物分类组成方面彼此显着不同，但在散装土壤中也显着不同。功能筛选显示，与大块土壤相比，木材中的新陈代谢潜力低，纤维素分解细菌的频率更高，这表明这些群落适应了该生境和腐烂木材中发生的物理化学条件。总之，我们的数据证明细菌对腐烂木材的定殖是基于将外在因素和内在因素联系在一起的确定性过程。功能筛选显示，与大块土壤相比，木材中的新陈代谢潜力低，纤维素分解细菌的频率更高，这表明这些群落适应了该生境和腐烂木材中发生的物理化学条件。总之，我们的数据证明细菌对腐烂木材的定殖是基于将外部和内在因素联系在一起的确定性过程。功能筛选显示，与大块土壤相比，木材中的新陈代谢潜力低，纤维素分解细菌的频率更高，这表明这些群落适应了该生境和腐烂木材中发生的物理化学条件。总之，我们的数据证明细菌对腐烂木材的定殖是基于将外部和内在因素联系在一起的确定性过程。