Differential impact of liana colonization on the leaf functional traits of co-occurring deciduous and evergreen trees in a tropical dry scrub forest

The present study was carried out to analyze the leaf functional traits of co-occurring evergreen and deciduous tree species in a tropical dry scrub forest. This study also intended to check whether the species with contrasting leaf habits differ in their leaf trait plasticity, responding to the canopy infestation by lianas. A total of 11 leaf functional traits were studied for eight tree species with contrasting leaf habits (evergreen and deciduous) and liana-colonization status (with or without liana). In the liana-free environment (L), evergreen trees had significantly higher leaf tissue density (LTD) and total chlorophyll (CHL) than the deciduous species. Whereas the deciduous trees had higher specific leaf area (SLA) and mass-based leaf nitrogen concentration (N). The leaf trait-pair relationship in the present study agreed with the well-established global trait-pair relationships (leaf thickness (LT) vs. SLA, N vs. LT, SLA vs. N, and LDMC vs. SLA). There was a significant difference between L and L individuals in leaf area (LA), petiole length (PL), SLA, LDMC, and CHL in the deciduous species. On the other hand, evergreen species showed marked differences across LT, SLA, LTD, N and chlorophyll components between L and L individuals of the same species. The results revealed the differential impact of liana colonization on the host trees with contrasting leaf habits. The deciduous species with the acquisitive strategy can have a competitive advantage over evergreen species in the exposed environments (L), whereas evergreen species with shade-tolerant properties were better acclimated to the shaded environments (L). Therefore, liana colonization can significantly impact the C-fixation strategies of the host trees by altering their light environment and further, the magnitude of such impact may vary among species of different leaf habits. The result also indicated the patterns of convergence and divergence in some of the leaf functional traits between evergreen and deciduous species explaining the patterns of species co-existence.