@article{2d5d5384de79443ab5f7416c91444ed6,
title = "Carbon starvation following a decade of experimental drought consumes old reserves in Pinus edulis",
abstract = "Shifts in the age or turnover time of non-structural carbohydrates (NSC) may underlie changes in tree growth under long-term increases in drought stress associated with climate change. But NSC responses to drought are challenging to quantify, due in part to large NSC stores in trees and subsequently long response times of NSC to climate variation. We measured NSC age (Δ14C) along with a suite of ecophysiological metrics in Pinus edulis trees experiencing either extreme short-term drought (−90% ambient precipitation plot, 2020–2021) or a decade of severe drought (−45% plot, 2010–2021). We tested the hypothesis that carbon starvation – consumption exceeding synthesis and storage – increases the age of sapwood NSC. One year of extreme drought had no impact on NSC pool size or age, despite significant reductions in predawn water potential, photosynthetic rates/capacity, and twig and needle growth. By contrast, long-term drought halved the age of the sapwood NSC pool, coupled with reductions in sapwood starch concentrations (−75%), basal area increment (−39%), and bole respiration rates (−28%). Our results suggest carbon starvation takes time, as tree carbon reserves appear resilient to extreme disturbance in the short term. However, after a decade of drought, trees apparently consumed old stored NSC to support metabolism.",
keywords = "bomb-spike, carbohydrates, mortality, nonstructural carbohydrates, radiocarbon, rain-out",
author = "Peltier, {Drew M.P.} and Carbone, {Mariah S.} and McIntire, {Cameron D.} and Nathan Robertson and Thompson, {R. Alex} and Shealyn Malone and Jim LeMoine and Richardson, {Andrew D.} and McDowell, {Nate G.} and Adams, {Henry D.} and Pockman, {William T.} and Trowbridge, {Amy M.}",
note = "Funding Information: We thank Lauren Baur, Renee Brown, and Don Natvig at the Sevilleta LTER, Michael Friedman for assistance with field monitoring, Chris Ebert and Kiona Ogle at NAU, and Xiaomei Xu at UC Irvine. We gratefully acknowledge the financial support of the Office of the President and Vice President of Research at Northern Arizona University for support in acquiring the MICADAS. This work was funded by the NSF via IOS‐RAPID‐1936205, IOS‐1755345, and IOS‐1755346, and NSF GRFP 1‐842493. HDA was also supported by the US Department of Agriculture, National Institute of Food and Agriculture, McIntire Stennis project 1019284. Funding Information: We thank Lauren Baur, Renee Brown, and Don Natvig at the Sevilleta LTER, Michael Friedman for assistance with field monitoring, Chris Ebert and Kiona Ogle at NAU, and Xiaomei Xu at UC Irvine. We gratefully acknowledge the financial support of the Office of the President and Vice President of Research at Northern Arizona University for support in acquiring the MICADAS. This work was funded by the NSF via IOS-RAPID-1936205, IOS-1755345, and IOS-1755346, and NSF GRFP 1-842493. HDA was also supported by the US Department of Agriculture, National Institute of Food and Agriculture, McIntire Stennis project 1019284. Publisher Copyright: {\textcopyright} 2023 The Authors New Phytologist {\textcopyright} 2023 New Phytologist Foundation This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.",
year = "2023",
month = oct,
doi = "10.1111/nph.19119",
language = "English (US)",
volume = "240",
pages = "92--104",
journal = "New Phytologist",
issn = "0028-646X",
publisher = "Wiley-Blackwell",
number = "1",
}