Data for "Short-Term Soil Microbial Succession Responds Conversely to Fire Severity across Temperate Single and Mixed Forests"

Amplicon sequencing raw data
Abstract
Background
Under intensifying global climate change, increased wildfires threat forest ecosystem functions by altering soil physicochemical properties and microbial communities. Post-fire soil microbial succession is interactively regulated by forest type, fire severity, and recovery time, yet their seasonal successional trajectories remain unclear. This study investigates how fire severity and forest type (single/mixed) regulate soil microbial composition, structure, and successional trajectories in northern China’s warm-temperate forests across non-growing (NGS) and growing seasons (GS), while identifying key soil physicochemical drivers.
Results
Results demonstrate fire significantly shifts seasonal successional trajectories by expanding bacterial seasonal niche differentiation and disrupting fungal seasonal stability. Succession transitions from NGS communities dominated by Muribaculaceae (bacteria) and Archaeorhizomyces (fungi) to GS communities dominated by stress-tolerant bacteria (e.g., Sphingomonas, Pseudomonas) and plant-symbiotic fungi (e.g., Russula, Inocybe). High-severity fire elevated pH, inhibiting acid-sensitive ectomycorrhizal fungi while exacerbating nitrogen-phosphorus limitation, promoting bacterial reliance on phosphorus metabolism repair and fungal enzymatic strategies for nutrient acquisition. Forest type significantly regulated soil microbial succession: high-severity fire in single forests caused SOC loss, replacement of oligotrophic Acidobacteriota by copiotrophic Proteobacteria, and severe fungal diversity decline. Conversely, mixed forests sustained mutualistic interactions involving Actinobacteria and drought-tolerant fungi (Mortierellales), demonstrating greater resilience. Soil pH, TN, and TP were identified as key drivers of microbial restructuring.
Conclusion
This study highlights that fire severity and forest type jointly shape short-time microbial succession by regulating soil pH, nutrient availability, and microhabitat stability after fire. Our results recommend prioritizing mixed forest conservation in fire-prone regions to enhance ecosystem resilience and microbial-mediated nutrient cycling.