DOI: 10.5061/dryad.zcrjdfnpb
title: Data from: Plasticity in hydraulic architecture: Riparian trees respond to increased temperatures with genotype-specific adjustments to leaf traits

description: Climate means and variability are shifting rapidly, leading to mismatches
 between climate and locally adapted plant traits. Phenotypic plasticity,
 the ability of a plant to respond to environmental conditions within a
 lifetime, may provide a buffer for plants to persist under increasing
 temperature and water stress. We used two reciprocal common gardens across
 a steep temperature gradient to investigate plasticity in six populations
 of Fremont cottonwood, an important foundation tree species in arid
 riparian ecosystems. We investigated two components of leaf hydraulic
 architecture: leaf venation and stomatal morphology, both of which
 regulate leaf water potential and photosynthesis. These traits will likely
 affect plant performance under climate stressors, but it is unclear
 whether they are controlled by genetic or environmental factors, and
 whether they respond to the environment in parallel or independent
 directions. We found that: 1) Populations had divergent responses to a
 hotter growing environment, increasing or decreasing vein density. 2)
 Populations showed surprisingly independent responses of venation vs.
 stomatal traits. 3) As a result of these different responses, plasticity
 in hydraulic architecture traits was not predictable from historic climate
 conditions at population source locations, and often varied substantially
 within populations. 4) Hydraulic architecture was clearly linked to
 growth, with higher vein and stomatal density predicting greater tree
 growth in the hottest growing environment. However, higher plasticity in
 these traits did not increase average growth across multiple environments.
 Thus, P. fremontii populations and genotypes vary in their capacity to
 adjust their leaf hydraulic architecture and support growth in contrasting
 environments, but that this plasticity is not clearly predictable or
 beneficial. Identifying genotypes suitable for future conditions will
 depend on the relative importance of multiple traits, and on both
 evolutionary and ecological responses to changing temperature and water
 availability.
description: # Plasticity in hydraulic architecture: Riparian trees respond to
 increased temperatures with genotype-specific adjustments to leaf traits
 **Dataset 1: vein_traits.csv** This file lists information about each tree
 (Garden, Population, Genotype) and the trait values for that tree.
 VTOTVD_mm = vein volume, vd_mm = vein density, witdth_mm = vein width,
 VLoop_mm = vein reticulation. **Dataset 2: stomatal_traits** This file
 lists information about each tree (Garden, Population, Genotype) and the
 trait values for that tree. sd = stomata density, Gsmax_molperm2pers =
 Gsmax, Length_mm = stomata length. **Dataset 3: growth.csv** This file
 lists information about each tree (Garden, Population, Genotype) and the
 trait values for that tree. All datasets: * Please refer to Table 2 of the
 manuscript for the long form names of the populations (e.g., CAF-AUG =
 Agua Fria, Horseshoe). * Garden column: AF = Agua Fria Garden, YU = Yuma
 Garden. * Garden.MAT = Mean Annual temperature of the Garden location. *
 Pop.MAT = Mean Annual Temperature of Population location. * Other columns
 including Plot, PlotX, PlotY, GarTree, Block refer to the sample location
 in the Garden. All climate and hydrology data is open source and available
 at the cited sources in manuscript (Climate WNA, USGS, and WorldClim).