Files
Abstract
In forests, mycorrhizal associations are key drivers of soil biogeochemistry. Previous literature has primarily focused on ectomycorrhizae (EcM) and arbuscular mycorrhizae (AM). Ericoid mycorrhizal (ErM) shrubs are common in forest understories but are rarely considered in biogeochemical studies. We investigated the effects of ErM shrubs on soil carbon (C) and nitrogen (N) in a southern Appalachian temperate forest. We sampled the 0-10 cm mineral soil layer from 43 plots at Coweeta Hydrologic Laboratory, across gradients in AM-EcM dominance and understory biomass of ErM shrubs. Total mineral-associated organic matter (MAOM) C and N was negatively associated with EcM trees, while proportion of particulate organic matter (POM) C and N was positively associated with ErM shrubs. This suggests ErM shrubs may facilitate POM formation while EcM trees impair MAOM formation. This supports previous evidence about ErM effects on soil organic matter (SOM), further advocating for their inclusion in future mycorrhizal-based SOM studies.