DOI: 10.5061/dryad.9s4mw6mtc
title: Data from: Predicting climatic limits along a rainfall gradient of dipterocarp species based on leaf turgor loss point

description: Drought tolerance is an integral determinant of drought survival in trees;
 thus, an accurate and rapid assessment of drought tolerance can lead to
 improved prediction of forest responses to droughts. The osmometer method
 enables the rapid determination of the leaf water potential at turgor loss
 (πtlp), a key parameter of drought tolerance, from the osmotic potential
 at full turgor (πsat). However, despite its wide applications, there have
 been few validations in ever-wet tropical rainforests. Here, we assessed
 the efficacy of the osmometer method in dipterocarps, a dominant tree
 group in SE Asia in ever-wet Malaysia, and examined the linkage between
 πtlp and distribution along a rainfall gradient. The πtlp determined using
 conventional method was strongly and linearly correlated with the πsat
 determined using an osmometer. The coefficients of our model were
 statistically identical to those previously represented, but with a
 slightly larger intercept (0.21 MPa). Species with more negative πtlp were
 distributed in drier habitats, with a relatively larger variation in πtlp
 for species confined to ever-wet climates than for those occurring in
 ever-wet and seasonally dry climates. Some leaf traits, individual leaf
 area and dry matter content, were associated with πtlp, but these traits
 alone could not predict species distribution. We demonstrated the
 robustness of osmometer method in ever-wet tropical rainforest species and
 that πtlp is associated with current distribution along large-scale
 moisture availabilities.
description: # Data from: Predicting climatic limits along a rainfall gradient of
 dipterocarp species based on leaf turgor loss point Dataset DOI:
 [10.5061/dryad.9s4mw6mtc](10.5061/dryad.9s4mw6mtc) ## Description of the
 data and file structure This dataset represents complete data used in this
 paper. ### Files and variables #### Files: ####
 ・230325data\_Kawai\_et\_al\_Biotropica\_πsat\_osm.csv ####
 ・080425data\_Kawai\_et\_al\_Biotropica\_P-Vcurve\_and\_other\_traits\_rev.csv #### ・230325data\_Kawai\_et\_al\_Biotropica\_Species\_distribution.csv **Description:**  "n/a" indicates no data.  ##### Variables * Species: name of species  * Individual: identity of individual within species  * Leaf: identity of leaf within individual * πsat_osm: osmotic potential at full turgor estimated from an osmometer. Unit in MPa. * πsat: osmotic potential at full turgor estimated from a pressure-volume curve. Unit in MPa. * πtlp: leaf water potential at turgor loss. Unit in MPa. * RWCtlp: relative water content at turgor loss. No units. * af: apoplastic water fraction. No units. * ε: modulus of elasticity. Unit in MPa. * Cleaf: leaf hydraulic capacitance. Unit in mol m^-2 MPa^-1. * LMA: leaf dry mass per area. Unit in g m^-2. * LDMC: leaf dry matter content. Unit in g g^-1. * LA: individual leaf area. Unit in cm^2. * MAP5th: 5th percentile of the mean annual rainfall. Unit in mm. * MAP50th: 50th percentile of the mean annual rainfall. Unit in mm. * MAP95th: 95th percentile of the mean annual rainfall. Unit in mm. * MPD5th: 5th percentile of  the mean precipitation of the driest month. Unit in mm. * MPD50th: 50th percentile of  the mean precipitation of the driest month. Unit in mm. * MPD95th: 95th percentile of  the mean precipitation of the driest month. Unit in mm.