Soil Carbon Sequestration Dynamics Under Differential Mycorrhizal Inoculation Regimes in Fragmented Temperate Deciduous Woodlands: A Microcosm-to-Landscape Scaling Analysis

Abstract

Mycorrhizal fungal networks play a pivotal yet poorly quantified role in mediating soil organic carbon (SOC) stabilization within fragmented temperate deciduous woodlands. This study examined arbuscular and ectomycorrhizal inoculation gradients across experimentally isolated woodland patches in central Germany, combining phospholipid fatty acid (PLFA) profiling, stable isotope (δ¹³C) tracing, and landscape-scale LiDAR-derived canopy fragmentation indices. Results from 48 monitored microcosm plots, upscaled using spatially explicit carbon flux modelling, demonstrated that ectomycorrhizal dominance significantly enhanced recalcitrant SOC fractions (particulate organic matter; POM) by 23.4% relative to arbuscular-dominated plots. Edge-effect amplification under high landscape fragmentation reduced mycorrhizal hyphal network continuity by up to 38%, substantially diminishing SOC stabilization efficiency. These findings highlight the critical interdependence between woodland patch geometry, mycorrhizal community structure, and long-term carbon sink functionality.