Functional coordination between branch hydraulic properties and leaf functional traits in miombo woodlands: implications for water stress management and species habitat preference

摘要

We investigated functional coordination between branch hydraulic properties and leaf functional traits among nine miombo woodlands canopy tree species differing in habitat preference and phenology. Specifically, we were seeking to answer the question: are branch hydraulic properties coordinated with leaf functional traits linked to plant drought tolerance in seasonally dry tropical forests and what are the implications for species habitat preference? The hydraulic properties investigated in this study were stem area specific hydraulic conductivity (K _S), Huber value (H _v), and xylem cavitation vulnerability (Ψ₅₀). The leaf functional traits measured were specific leaf area (SLA), leaf dry matter content (LDMC), and mean leaf area (MLA). Generalists displayed significantly (P < 0.05) higher cavitation resistance (Ψ₅₀) and SLA, but lower sapwood specific hydraulic conductivity (K _S), leaf specific conductivity (K _L), MLA, and LDMC than mesic specialists. Although MLA was uncorrelated with Ψ₅₀, we found significant (P < 0.05) positive and negative correlations between plant hydraulic properties and leaf functional traits linked to plant drought tolerance ability, indicating that the interactions between branch hydraulics and leaf functional traits related to plant drought tolerance ability may influence tree species habitat preference in water-limited ecosystems.