Carbon Allocation and Water Relations of Lianas Versus Trees.

ERIC MANZANÉ; ADELA M. PANIZZA; MARIANA VILLAGRA; YA-JUN CHEN; DÉBORA DI FRANCESCANTONIO; PAULA I. CAMPANELLO; LOUIS S. SANTIAGO ; YONG-JIANG ZHANG; SABRINA A. RODRIGUEZ; GUILLERMO GOLDSTEIN

Tropical Tree Physiology. Adaptations and Responses in a Changing Environment.

Springer

Año: 2016; p. 319 - 336

Abstract Despite lianas being fundamental components of tropical and subtropicalforest ecosystems throughout the world, the physiological characteristics of thisgrowth form are not well known. Different behaviors at the seedling stage wereuntil recently largely unnoticed. In one extreme of a continuum of adaptive traits,freestanding liana seedlings invest a large proportion of biomass in self-supporttissue while on the other extreme support-seeker seedlings invest more resources inrapid elongation of slender stems with an efficient hydraulic conductive system.Adult lianas often have lower wood density and higher specific leaf area than treesand have most of their leaves deployed at the top of the canopy, experiencing high>irradiance and transpirational demands, which requires effective regulation of waterloss to avoid desiccation. Recent studies show that lianas have faster stomatalresponses to increasing vapor pressure deficit (VPD) and exhibit stronger partialstomatal closure compared to trees. Strong stomatal control and efficient watertransport help lianas maintain leaf water potential (Ψleaf) within a safe hydraulicrange to avoid xylem dysfunction despite their low stem water storage capacity,which is achieved at a minimum cost in terms of carbon assimilation. Liana colonization of tree crowns can significantly reduce tree growth and transpiration withconsequences for carbon and water economy at individual tree and ecosystemlevels.