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Title: Drought drives rapid shifts in tropical rainforest soil biogeochemistry and greenhouse gas emissions

Abstract

Climate change models predict more frequent and severe droughts in the humid tropics. How drought will impact tropical forest carbon and greenhouse gas dynamics is poorly understood. Here we report the effects of the severe 2015 Caribbean drought on soil moisture, oxygen, phosphorus (P), and greenhouse gas emissions in a humid tropical forest in Puerto Rico. Drought significantly decreases inorganic P concentrations, an element commonly limiting to net primary productivity in tropical forests, and significantly increases organic P. High-frequency greenhouse gas measurements show varied impacts across topography. Soil carbon dioxide emissions increase by 60% on slopes and 163% in valleys. Methane (CH4) consumption increases significantly during drought, but high CH4 fluxes post-drought offset this sink after 7 weeks. The rapid response and slow recovery to drought suggest tropical forest biogeochemistry is more sensitive to climate change than previously believed, with potentially large direct and indirect consequences for regional and global carbon cycles

Authors:
ORCiD logo [1];  [1]; ORCiD logo [1]
  1. Univ. of California, Berkeley, CA (United States)
Publication Date:
Research Org.:
Univ. of California, Berkeley, CA (United States)
Sponsoring Org.:
Office of Science (SC), Biological and Environmental Research (BER). Earth and Environmental Systems Science Division
Contributing Org.:
International Institute of Tropical Forestry, USDA Forest Service, University of Puerto Rico, LBNL, LLNL
OSTI Identifier:
1484042
Report Number(s):
DOE-UCB-10567-1
Journal ID: ISSN 2041-1723
Grant/Contract Number:  
SC0010567
Resource Type:
Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 9; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 58 GEOSCIENCES; Biogeosciences; data-model synthesis; tropical forest; greenhouse gases; oxygen; drought; hurricanes

Citation Formats

O’Connell, Christine S., Ruan, Leilei, and Silver, Whendee L. Drought drives rapid shifts in tropical rainforest soil biogeochemistry and greenhouse gas emissions. United States: N. p., 2018. Web. doi:10.1038/s41467-018-03352-3.
O’Connell, Christine S., Ruan, Leilei, & Silver, Whendee L. Drought drives rapid shifts in tropical rainforest soil biogeochemistry and greenhouse gas emissions. United States. https://doi.org/10.1038/s41467-018-03352-3
O’Connell, Christine S., Ruan, Leilei, and Silver, Whendee L. Mon . "Drought drives rapid shifts in tropical rainforest soil biogeochemistry and greenhouse gas emissions". United States. https://doi.org/10.1038/s41467-018-03352-3. https://www.osti.gov/servlets/purl/1484042.
@article{osti_1484042,
title = {Drought drives rapid shifts in tropical rainforest soil biogeochemistry and greenhouse gas emissions},
author = {O’Connell, Christine S. and Ruan, Leilei and Silver, Whendee L.},
abstractNote = {Climate change models predict more frequent and severe droughts in the humid tropics. How drought will impact tropical forest carbon and greenhouse gas dynamics is poorly understood. Here we report the effects of the severe 2015 Caribbean drought on soil moisture, oxygen, phosphorus (P), and greenhouse gas emissions in a humid tropical forest in Puerto Rico. Drought significantly decreases inorganic P concentrations, an element commonly limiting to net primary productivity in tropical forests, and significantly increases organic P. High-frequency greenhouse gas measurements show varied impacts across topography. Soil carbon dioxide emissions increase by 60% on slopes and 163% in valleys. Methane (CH4) consumption increases significantly during drought, but high CH4 fluxes post-drought offset this sink after 7 weeks. The rapid response and slow recovery to drought suggest tropical forest biogeochemistry is more sensitive to climate change than previously believed, with potentially large direct and indirect consequences for regional and global carbon cycles},
doi = {10.1038/s41467-018-03352-3},
journal = {Nature Communications},
number = 1,
volume = 9,
place = {United States},
year = {Mon Apr 09 00:00:00 EDT 2018},
month = {Mon Apr 09 00:00:00 EDT 2018}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 93 works
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Figures / Tables:

Figure 1 Figure 1: Recent annual precipitation data for El Verde Research Station. Years 2004–2013 serve as recent comparison (mean and ±1 s.d. reported); this study includes observational data collected from 2014 to 2015

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Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.