Mycorrhiza Better Predict Soil Fungal Community Composition and Function than Aboveground Traits in Temperate Forest Ecosystems

Abstract Forests in the northeastern US are experiencing shifts community composition due to northward migration of warm-adapted tree species and certain species’ declines (for example, white ash eastern hemlock) invasive insects. Changes belowground fungal communities associated functions will inevitably follow. Therefore, we sought investigate relative importance two important characteristics—mycorrhizal type [ectomycorrhizal (EcM) or arbuscular mycorrhizal (AM)] leaf habit (deciduous evergreen) on soil organic matter cycling. We sampled mineral horizons beneath AM-associated ( Fraxinus americana Thuja occidentalis) ECM-associated Betula alleghaniensis Tsuga canadensis ), with an evergreen deciduous each group. To characterize decomposition species, sequenced ITS1 region DNA measured potential activity carbon- nitrogen-targeting extracellular enzymes. Each harbored distinct communities, supporting need consider both habit. However, between characteristics, better predicted communities. Across guilds, saprotrophic fungi were most group shaping differences soils all species. The effect hydrolytic enzymes depended association horizon, while oxidative enzyme activities higher EcM-associated trees across habits.