Journal Article

Tropical tree mortality has increased with rising atmospheric water stress

Santos-Andrade, Paul, E, David Bauman was funded by the Belgian American Educational Foundation (BAEF), the Philippe Wiener–Maurice Anspach Foundation, and the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 895799, University of New South Wales [Sydney] (UNSW), Australian National University (ANU), Universidad Nacional de San Antonio Abad del Cusco (UNSAAC), James Cook University (JCU), Bentley, Lisa Patrick, European Project: 895799,TropDemTrait, Rifai, Sami W, Malhi, Yadvinder, University of Leeds, Sonoma State University [Rohnert Park], Oliveras Menor, Imma, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-U

2022

Overview

Evidence exists that tree mortality is accelerating in some regions of the tropics1,2, with profound consequences for the future of the tropical carbon sink and the global anthropogenic carbon budget left to limit peak global warming below 2 °C. However, the mechanisms that may be driving such mortality changes and whether particular species are especially vulnerable remain unclear3–8. Here we analyse a 49-year record of tree dynamics from 24 old-growth forest plots encompassing a broad climatic gradient across the Australian moist tropics and find that annual tree mortality risk has, on average, doubled across all plots and species over the last 35 years, indicating a potential halving in life expectancy and carbon residence time. Associated losses in biomass were not offset by gains from growth and recruitment. Plots in less moist local climates presented higher average mortality risk, but local mean climate did not predict the pace of temporal increase in mortality risk. Species varied in the trajectories of their mortality risk, with the highest average risk found nearer to the upper end of the atmospheric vapour pressure deficit niches of species. A long-term increase in vapour pressure deficit was evident across the region, suggesting that thresholds involving atmospheric water stress, driven by global warming, may be a primary cause of increasing tree mortality in moist tropical forests.

• Publisher: Nature Publishing Group,HAL CCSD,Nature Publishing Group UK
• Subject: 631/158/1745 / 631/158/2165 / 631/158/2450 / 631/158/2454 / 631/158/853 / Acclimatization / Anthropogenic factors / Atmosphere - chemistry / Atmospheric water / Australia / Biodiversity / Biodiversity and Ecology / Biomass / Botanics / Carbon / Carbon - metabolism / Carbon budget / Carbon Sequestration / Carbon sinks / Climate change / Climate prediction / Cyclones / Dehydration / Ecology, environment / Ecosystems / Environmental Sciences / Forests / Global warming / Global Warming - statistics & numerical data / Health risks / History, 20th Century / History, 21st Century / Humanities and Social Sciences / Humidity / Life expectancy / Life Sciences / Life span / Local climates / Mortality / Mortality risk / multidisciplinary / Population Density / Risk / Science / Science (multidisciplinary) / Species / Stress, Physiological / Systematics, Phylogenetics and taxonomy / Threatened species / Time Factors / Trees / Trees - classification / Trees - growth & development / Trees - metabolism / Tropical Climate / Tropical environments / Tropical forests / Vapor pressure / Vegetal Biology / Water - analysis / Water - metabolism / Water stress
• ISBN: 0007973324000