Leaf and root of Machilus pauhoi both exhibit different resource acquisition strategies when mixed with evergreen broad-leaved tree species compared to deciduous ones in a mid-subtropical region of China

Mixed forest has become a key approach for enhancing productivity and ecological functions of plantations. Machilus pauhoi is a native precious fast-growing evergreen broad-leaved tree species with multiple functions. However, functional traits and resource utilization strategies after mixture with different life-form plants remain unclear. This study evaluated leaf and root traits of M. pauhoi from three forests (pure forest (CT), mixed forest with Cerasus campanulata (deciduous broad-leaved (MC)), mixed forest with Magnoliaceae glanca (evergreen broad-leaved (MM))). M. pauhoi in MM exhibited higher specific leaf area, leaf relative water content, specific root length and root specific surface area, lower leaf dry matter content and leaf thickness than in MC and CT. No significant differences were observed in leaf and fine root traits between CT and MC. Leaf, root and whole-plant traits were consistently resource-acquisitive in MM. Root trait variation was more sensitive to soil environment compared to leaf traits. The different mixed patterns did not alter the relationship between phenotypic integration and plasticity. This research provided theoretical and technical references for elucidating response characteristics to mixed forests, selecting suitable tree species for mixing and efficiently cultivating plantations. It makes scientific recommendations for sustainable management of precious species plantations across subtropical regions.