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Title: Precipitation, not air temperature, drives functional responses of trees in semi-arid ecosystems

Abstract

Model scenarios of climate change predict that warming and drought will occur simultaneously in the future in many regions. The capacity of woody species to modify their physiology and morphology in response to environmental conditions is widely recognized, but little is known about the responses of trees to reduced precipitation and increased temperature acting simultaneously. In a semi-arid woodland, we assessed in this paper the responses in physiological (needle emergence, maximum photosynthesis, stomatal conductance, water use efficiency (WUE) and shoot elongation) and morphological (needle length and thickness, and leaf mass per area (LMA)) foliar traits of piñon pine (Pinus edulis) in response to three years of a 45% reduction in precipitation, a 4.8 °C increase in air temperature and their simultaneous effects. A strong change in physiological and morphological traits in response to reduced precipitation was observed. Precipitation reduction delayed needle emergence, decreased photosynthesis and stomatal conductance, increased WUE, decreased shoot elongation and induced shorter needles with a higher LMA. Trees subjected to simultaneous reductions in precipitation and warming demonstrated a similar response. However, atmospheric warming did not induce a response in any of the measured traits. Physiological and morphological traits of trees in this semi-arid climate were more responsivemore » to changes in soil moisture than air temperature. Long-term exposure to seasonal drought stress in arid sites may have resulted in strong plastic responses to this first stressor. However, atmospheric warming probably was not experienced as a stress for trees in this warm and dry climate. Finally and overall, our results indicate that in semi-arid ecosystems where tree functioning is already highly limited by soil water availability, atmospheric warming as anticipated with climate change may have less impact on foliar trait responses than previously thought.« less

Authors:
 [1];  [1];  [2];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Oklahoma State Univ., Stillwater, OK (United States). Dept. of Plant Biology, Ecology, and Evolution
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1409755
Report Number(s):
LA-UR-16-20727
Journal ID: ISSN 0022-0477
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Ecology
Additional Journal Information:
Journal Volume: 105; Journal Issue: 1; Journal ID: ISSN 0022-0477
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; climate change; ecophysiology; foliar traits; growth; needle structure; phenology; photosynthesis; Pinus edulis Engelm; plasticity; water use efficiency

Citation Formats

Grossiord, Charlotte, Sevanto, Sanna, Adams, Henry D., Collins, Adam D., Dickman, Lee T., McBranch, Natalie, Michaletz, Sean T., Stockton, Elizabeth A., Vigil, Miguel, and McDowell, Nate G. Precipitation, not air temperature, drives functional responses of trees in semi-arid ecosystems. United States: N. p., 2016. Web. doi:10.1111/1365-2745.12662.
Grossiord, Charlotte, Sevanto, Sanna, Adams, Henry D., Collins, Adam D., Dickman, Lee T., McBranch, Natalie, Michaletz, Sean T., Stockton, Elizabeth A., Vigil, Miguel, & McDowell, Nate G. Precipitation, not air temperature, drives functional responses of trees in semi-arid ecosystems. United States. doi:10.1111/1365-2745.12662.
Grossiord, Charlotte, Sevanto, Sanna, Adams, Henry D., Collins, Adam D., Dickman, Lee T., McBranch, Natalie, Michaletz, Sean T., Stockton, Elizabeth A., Vigil, Miguel, and McDowell, Nate G. 2016. "Precipitation, not air temperature, drives functional responses of trees in semi-arid ecosystems". United States. doi:10.1111/1365-2745.12662. https://www.osti.gov/servlets/purl/1409755.
@article{osti_1409755,
title = {Precipitation, not air temperature, drives functional responses of trees in semi-arid ecosystems},
author = {Grossiord, Charlotte and Sevanto, Sanna and Adams, Henry D. and Collins, Adam D. and Dickman, Lee T. and McBranch, Natalie and Michaletz, Sean T. and Stockton, Elizabeth A. and Vigil, Miguel and McDowell, Nate G.},
abstractNote = {Model scenarios of climate change predict that warming and drought will occur simultaneously in the future in many regions. The capacity of woody species to modify their physiology and morphology in response to environmental conditions is widely recognized, but little is known about the responses of trees to reduced precipitation and increased temperature acting simultaneously. In a semi-arid woodland, we assessed in this paper the responses in physiological (needle emergence, maximum photosynthesis, stomatal conductance, water use efficiency (WUE) and shoot elongation) and morphological (needle length and thickness, and leaf mass per area (LMA)) foliar traits of piñon pine (Pinus edulis) in response to three years of a 45% reduction in precipitation, a 4.8 °C increase in air temperature and their simultaneous effects. A strong change in physiological and morphological traits in response to reduced precipitation was observed. Precipitation reduction delayed needle emergence, decreased photosynthesis and stomatal conductance, increased WUE, decreased shoot elongation and induced shorter needles with a higher LMA. Trees subjected to simultaneous reductions in precipitation and warming demonstrated a similar response. However, atmospheric warming did not induce a response in any of the measured traits. Physiological and morphological traits of trees in this semi-arid climate were more responsive to changes in soil moisture than air temperature. Long-term exposure to seasonal drought stress in arid sites may have resulted in strong plastic responses to this first stressor. However, atmospheric warming probably was not experienced as a stress for trees in this warm and dry climate. Finally and overall, our results indicate that in semi-arid ecosystems where tree functioning is already highly limited by soil water availability, atmospheric warming as anticipated with climate change may have less impact on foliar trait responses than previously thought.},
doi = {10.1111/1365-2745.12662},
journal = {Journal of Ecology},
number = 1,
volume = 105,
place = {United States},
year = 2016,
month = 9
}

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