Hopkins Jacob R, Vizzari Giuseppina, Bennett Alison E, Malacrinò Antonino
Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, Ohio, USA.
Department of Biology, Indiana University, Bloomington, Indiana, USA.
Glob Chang Biol. 2025 Aug;31(8):e70386. doi: 10.1111/gcb.70386.
Fire is a globally pervasive force reshaping ecosystems, yet its influence on the ecological processes structuring soil microbiomes remains poorly understood. Using a meta-analysis of > 2600 amplicon sequencing samples across 19 global studies, we tested whether fire alters soil microbiome assembly processes, diversity, and ecological selection for pyrophilic specialists. Contrary to prevailing assumptions, we found that fire did not significantly shift ecological selection processes in bacteria or fungi but instead constrained dispersal, particularly reducing dispersal in bacterial and fungal communities and increasing ecological drift in fungi. Despite limited evidence for ecological selection, fire consistently filtered for specialist taxa, increasing their relative abundance across microbial communities. Fire also reduced fungal diversity and evenness, while bacterial communities exhibited greater dominance and loss of rare taxa. These findings support the idea that fire promotes microbial post-fire niche specialization while disrupting dispersal pathways. Our results indicate that increasing fire frequency and severity under climate change may homogenize soil microbial communities, reduce microbial resilience, and constrain ecosystem recovery.
火灾是一种重塑生态系统的全球性普遍力量，然而其对构建土壤微生物群落的生态过程的影响仍知之甚少。通过对19项全球研究中的2600多个扩增子测序样本进行荟萃分析，我们测试了火灾是否会改变土壤微生物群落的组装过程、多样性以及对嗜热专家的生态选择。与普遍假设相反，我们发现火灾并未显著改变细菌或真菌的生态选择过程，而是限制了扩散，特别是减少了细菌和真菌群落中的扩散，并增加了真菌中的生态漂变。尽管生态选择的证据有限，但火灾始终对特定类群进行筛选，增加了它们在微生物群落中的相对丰度。火灾还降低了真菌的多样性和均匀度，而细菌群落则表现出更大的优势和稀有类群的丧失。这些发现支持了火灾促进火灾后微生物生态位特化同时扰乱扩散途径的观点。我们的结果表明，气候变化下火灾频率和严重程度的增加可能会使土壤微生物群落同质化，降低微生物恢复力，并限制生态系统恢复。
