Unlocking soil carbon potential in giant panda habitat

ABSTRACT:

Forest management in giant panda habitats necessitates strategies that simultaneously support biodiversity and ecosystem carbon sequestration. Here, we demonstrate that protecting understory vegetation is indispensable for sustaining the soil carbon sink in restored subalpine coniferous plantations. Through a field experiment comparing natural forest with unthinned and thinned plantations (with or without understory removal), we uncovered a critical microbial mechanism. Understory removal triggered a detrimental cascade by elevating soil pH and shifting the carbon pool from labile to recalcitrant dominance. This environmental shift imposed a strong deterministic filter (Normalized stochasticity ratio, NST = 39.8%) on the microbial community, displacing pH-sensitive, labile carbon-dependent taxa (e.g., Gaiella) while enriching oligotrophs adept at recalcitrant carbon degradation (e.g., Ktedonobacter, Streptomyces). Community restructuring drove a functional metamorphosis: it reduced antibiotic synthesis and, under the dual stress of high pH and carbon quality decline, induced a novel RNA modification response (via N4-acetylcytidine accumulation) that enhanced the synthesis of recalcitrant carbon-degrading enzymes. Crucially, these adaptations precipitated a significant decline in microbial carbon use efficiency (CUE), shifting the soil carbon cycle from an accumulation to an inefficient consumption phase. Our findings provide a mechanistic basis for using understory vegetation as a primary tool to align giant panda habitat conservation with climate-smart forestry goals.

INSTRUMENT(S): Liquid Chromatography MS - positive, Liquid Chromatography MS - negative

PROVIDER: MTBLS13433 | MetaboLights | 2025-12-02

REPOSITORIES: MetaboLights