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Extreme drought impacts have been underestimated in grasslands and shrublands globally

Melinda D. Smith·Kate D Wilkins·Martin C. Holdrege·Peter A. Wilfahrt·Scott L. Collins·Alan K. Knapp·Osvaldo E. Sala·Jeffrey S. Dukes·Richard P. Phillips·Laura Yahdjian·Laureano A. Gherardi·Timothy Ohlert·Claus Beier·Lauchlan H. Fraser·Anke Jentsch·Michael E. Loik·Fernando T. Maestre·Sally A. Power·Qiang Yu·Andrew J. Felton·Seth M. Munson·Yiqi Luo·Hamed Abdoli·Mehdi Abedi·Concepcion L. Alados·Juan Alberti·Moshe Alon·Hui An·Brian Anacker·Maggie Anderson·Harald Auge·Seton Bachle·Khadijeh Bahalkeh·Michael Bahn·Amgaa Batbaatar·Taryn Bauerle·Karen H. Beard·Kai Behn·Ilka Beil·Lucio Biancari·Irmgard Blindow·Viviana Florencia Bondaruk·Elizabeth T. Borer·Edward W. Bork·Carlos Martin Bruschetti·Kerry M. Byrne·James F. Cahill Jr.·Dianela A. Calvo·Michele Carbognani·Augusto Cardoni·Cameron N. Carlyle·Miguel Castillo-Garcia·Scott X. Chang·Jeff Chieppa·Marcus V. Cianciaruso·Ofer Cohen·Amanda L. Cordeiro·Daniela F. Cusack·Sven Dahlke·Pedro Daleo·Carla M. D'Antonio·Lee H. Dietterich·Tim S. Doherty·Maren Dubbert·Anne Ebling·Nico Eisenhauer·Felicia M. Fischer·T’ai G. W. Forte·Tobias Gebauer·Beatriz Gozalo·Aaron C. Greenville·Karlo G. Guidoni-Martins·Heather J. Hannusch·Siri Vatso Haugum·Yann Hautier·Mariet Hefting·Hugh A. L. Henry·Daniela Hoss·Johannes Ingrisch·Oscar Iribarne·Forest Isbell·Yari Johnson·Samuel E. Jordan·Eugene F. Kelly·Kaitlin Kimmel·Juergen Kreyling·György Kröel-Dulay·Alicia Kropfl·Angelika Kubert·Andrew Kulmatiski·Eric G. Lamb·Klaus Steenberg Larsen·Julie Larson·Jason Lawson·Cintia V. Leder·Anja Linstadter·Jielin Liu·Shirong Liu·Alexandra G. Lodge·Grisel Longo
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Abstract

Drought has well-documented societal and economic consequences. Climate change is expected to intensify drought to even more extreme levels, but because such droughts have been historically rare, their impact on ecosystem functioning is not well known. We experimentally imposed the most frequent type of intensified drought—one that is ~1 y in duration—at 100 grassland and shrubland sites distributed across six continents. We found that loss of aboveground plant growth, a key measure of ecosystem function, was 60% greater when short-term drought was extreme (≤1-in-100-y historical occurrence). This drought-induced loss in function greatly exceeds previously reported losses for grasslands and shrublands, suggesting that the global impacts of projected increases in drought severity have been substantially underestimated.

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Melinda D. Smith, Kate D Wilkins, Martin C. Holdrege, Peter A. Wilfahrt, Scott L. Collins, Alan K. Knapp, Osvaldo E. Sala, Jeffrey S. Dukes, Richard P. Phillips, Laura Yahdjian, Laureano A. Gherardi, Timothy Ohlert, Claus Beier, Lauchlan H. Fraser, Anke Jentsch, Michael E. Loik, Fernando T. Maestre, Sally A. Power, Qiang Yu, Andrew J. Felton, Seth M. Munson, Yiqi Luo, Hamed Abdoli, Mehdi Abedi, Concepcion L. Alados, Juan Alberti, Moshe Alon, Hui An, Brian Anacker, Maggie Anderson, Harald Auge, Seton Bachle, Khadijeh Bahalkeh, Michael Bahn, Amgaa Batbaatar, Taryn Bauerle, Karen H. Beard, Kai Behn, Ilka Beil, Lucio Biancari, Irmgard Blindow, Viviana Florencia Bondaruk, Elizabeth T. Borer, Edward W. Bork, Carlos Martin Bruschetti, Kerry M. Byrne, James F. Cahill Jr., Dianela A. Calvo, Michele Carbognani, Augusto Cardoni, Cameron N. Carlyle, Miguel Castillo-Garcia, Scott X. Chang, Jeff Chieppa, Marcus V. Cianciaruso, Ofer Cohen, Amanda L. Cordeiro, Daniela F. Cusack, Sven Dahlke, Pedro Daleo, Carla M. D'Antonio, Lee H. Dietterich, Tim S. Doherty, Maren Dubbert, Anne Ebling, Nico Eisenhauer, Felicia M. Fischer, T’ai G. W. Forte, Tobias Gebauer, Beatriz Gozalo, Aaron C. Greenville, Karlo G. Guidoni-Martins, Heather J. Hannusch, Siri Vatso Haugum, Yann Hautier, Mariet Hefting, Hugh A. L. Henry, Daniela Hoss, Johannes Ingrisch, Oscar Iribarne, Forest Isbell, Yari Johnson, Samuel E. Jordan, Eugene F. Kelly, Kaitlin Kimmel, Juergen Kreyling, György Kröel-Dulay, Alicia Kropfl, Angelika Kubert, Andrew Kulmatiski, Eric G. Lamb, Klaus Steenberg Larsen, Julie Larson, Jason Lawson, Cintia V. Leder, Anja Linstadter, Jielin Liu, Shirong Liu, Alexandra G. Lodge, Grisel Longo. 2024-01-08. Extreme drought impacts have been underestimated in grasslands and shrublands globally. https://doi.org/10.1073/pnas.2309881120

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