DOI: 10.5061/dryad.z8w9ghxnp
title: Data from: Wood anatomical and hydraulic traits of Tamarix species across a large Eurasian gradient show a stronger climatic than phylogenetic signal

description: Aim: Tamarisk (Tamarix) is the predominant but taxonomically complex genus
 of the Tamaricaceae. The morphologically similar shrub or tree species
 grow in arid, salt-influenced habitats of Eurasia and Africa. We sampled
 woody shoots of seven species at the eastern margin (NW China;
 T. ramosissima) and the centre (Uzbekistan; T. hispida)
 of the Indo-Turanian region as well as at the eastern (Israel;
 T. aphylla, T. negevensis, T. nilotica) and
 western margin (southern Spain; T. boveana, T. gallica)
 of the Mediterranean region, the two diversity centres of the genus. To
 explore the drivers of intrageneric trait variability, we investigated
 whether differences in the anatomical-hydraulic wood traits among the
 species are related to climate or phylogeny. Location: Eurasia. Taxon:
 Tamarix L. (Tamaricaceae). Methods: We determined features of wood anatomy
 and calculated the hydraulic conductivity (kt) and the water potential at
 50% loss of hydraulic conductance (P50). We related these traits to
 climate variables and to the phylogenetic distances among the species.
 Results: Tamarix nilotica, T. negevensis and
 T. ramosissima exhibited large conduit areas, large hydraulic
 diameters and high kt, whereas the Spanish species T. gallica and
 T. boveana displayed high wood densities and a small fraction of
 large conduits. The phylogenetically distant species T. aphylla
 and T. hispida took intermediate positions. Tamarix ramosissima,
 which grows in regions with cold winters and hot-dry summers, exhibited
 the most negative P50 values, indicative of a low susceptibility to a
 failure of the water-conducting system. Trait differences among the
 species were unrelated to the species' phylogenetic relatedness but
 correlated with climate variables. Main Conclusions: Despite strong
 similarity in morphology and habitat preferences, Tamarix species
 displayed significant differences in their anatomical-hydraulic traits.
 These differences were related to climate conditions rather than phylogeny
 and are indicative of specific local adaptations to environmental
 conditions.
description: # **Wood anatomical and hydraulic traits of *Tamarix* species across a
 large Eurasian gradient**
 [https://doi.org/10.5061/dryad.z8w9ghxnp](https://doi.org/10.5061/dryad.z8w9ghxnp) In the "Wood traits" spreadsheet, the *Tamarix* species, samplings sites, the number of plants sampled, and the individual samples are listed together with their wood anatomical and hydraulic traits. The "Conduit area distribution" spreadsheet provides the classes of conduit areas and the log percentages of conduits in the individual conduit area classes for the *Tamarix* species listed in the "Wood traits" spreadsheet. ## Description of the data and file structure Conduits are the individual water-conducting elements of the wood (xylem). % Conduit area refers to the total cross-sectional area of all conduits related to a unit cross section of the xylem. *k*ttot is the hydraulic conductivity of the xylem, related to a unit cross section of the xylem. *k*tcond is the hydraulic conductivity of the xylem, related to the sum of the conduit areas of the respective cross-sectional area analysed. *d*h is the hydraulic diameter of the conduits, calculated according to Kolb, K. J., & Sperry, J. S. (1999), Differences in drought adaptation between subspecies of sagebrush *(Artemisia tridentata)*. *Ecology, 80*(7), 2373-2384. *P*50 is the xylem water potential at 50% loss of hydraulic conductance, calculated according to Hacke, U. G., Sperry, J. S., Pockman, W. T., Davis, S. D., & McCulloh, K. A. (2001), Trends in wood density and structure are linked to prevention of xylem implosion by negative pressure. *Oecologia, 126*(4), 457-461. doi:10.1007/s004420100628. "n/a" means "no data available".