Evaluation of the relationship between soil properties and functional traits in three forest types in a subtropical mountain in Mexico

Although it is well-established that soil nutrients determine leaf morpho-physiology and tree dimensions, linking soil physicochemical properties with functional community patterns under field conditions remains difficult. We examine how soil properties shape community-weighted mean (CWM) traits and species composition in pine, mixed, and broadleaf forests along a topographic gradient in the subtropical mountains of western Mexico. We related pH, organic matter, calcium, boron, and silt with stomatal density, stomatal conductance, leaf water potential (Ψ), specific leaf area (SLA), diameter at breast height (DBH), and tree height across three forest types and nine 1000 m 2 plots along the gradient. Pine forests, with distinct species composition, occupied stressful environments characterized by acidic soils and low organic matter. They adopted a conservative resources use strategy, with lower CWM-SLA and higher CWM-DBH, along with less negative CWM-Ψ, indicating reduced water stress compared to broadleaf and mixed forests. In contrast, broadleaf and mixed forests inhabit soils without nutrient limitations, showed a more acquisitive strategy, and high species turnover resulted in similar CWM values between them. This functional heterogeneity may be a key factor in the resilience of subtropical forest to disturbances.