『Abstract
　Vascular plants and associated microbial communities affect the nutrient resources of terrestrial ecosystems by impacting chemical weathering that transfers elements from primary minerals to other ecosystem pools, and chemical denudation that transports weathered elements out of the system in solution. We performed a year-long replicated flow-through column growth experiment to isolate the effects of vascular plants, ectomycorrhiza-forming fungi and associated bacteria on chemical weathering and chemical denudation. The study focused on Ca²⁺, K⁺ and Mg²⁺, for which the sole sources were biotite and anorthite mixed into silica sand. Concentrations of the cations were measured in input and output solutions, and three times during the year in plant biomass and on exchangeable cation sites of the growth medium. Weathering and denudation fluxes were estimated by mass balance, and mineral surface changes, biofilm and microbial attachments to surfaces were investigated with scanning electron microscopy. Both bacteria and fungi increased weathering fluxes compared to abiotic controls. Without a host plant denudation rates were as large as weathering rates i.e. the weathering to denudation ratio was about one. Based on whole year fluxes, ectomycorrhizal seedlings produced the greatest weathering to denudation ratios (1.5). Non-ectomycorrhizal seedlings also showed a high ratio of 1.3. Both ectomycorrhizal hyphal networks and root hairs of non-ectomycorrhizal trees, embedded in biofilm (microorganisms surrounded by extracellular polymers), transferred nutrients to the host while drainage losses were minimized. These results suggest that biofilms localize both weathering and plant nutrient uptake, isolating the root-hypha-mineral interface from bulk soil solution.

Keywords: biofilm; chemical weathering; chemical denudation; column experiment; ectomycorrhiza; root-hypha-mineral interface

Abbreviation
EMF=Ectomycorrhiza-forming fungi』

Introduction
Materials and methods
　Growth medium and inoculation
　Experimental design and conditions
　Sample collection and analyses
　Calculations and statistics
Results
　Cation uptake by pine
　Drainage water chemistry
　Exchangeable cations
　Mineral surfaces
　Chemical weathering and denudation mass-balance
Discussion
　Effect of vascular host on microbial and fungal weathering and denudation
　Bacterial and fungal weathering and denudation dynamics without vascular host
Summary and conclusions
Acknowledgments
References