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Cited by 148Plant Water Relations and Carbon DynamicsHydrology and Drought AnalysisRemote Sensing in Agriculture

Vulnerability of Amazonian forests to repeated droughts

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Anderson, Liana Oighenstein, Ribeiro Neto, Germano, Cunha, Ana Paula, Fonseca, Marisa Gesteira, Mendes de Moura, Yhasmin, Dalagnol, Ricardo, Wagner, Fabien Hubert, de Aragão, Luiz Eduardo Oliveira e Cruz·2018·Philosophical Transactions of the Royal Society B: Biological Sciences
DOI 10.1098/rstb.2017.0411PMC PMC6178446
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Abstract

Extreme droughts have been recurrent in the Amazon over the past decades, causing socio-economic and environmental impacts. Here, we investigate the vulnerability of Amazonian forests, both undisturbed and human-modified, to repeated droughts. We defined vulnerability as a measure of (i) exposure, which is the degree to which these ecosystems were exposed to droughts, and (ii) its sensitivity, measured as the degree to which the drought has affected remote sensing-derived forest greenness. The exposure was calculated by assessing the meteorological drought, using the standardized precipitation index (SPI) and the maximum cumulative water deficit (MCWD), which is related to vegetation water stress, from 1981 to 2016. The sensitivity was assessed based on the enhanced vegetation index anomalies (AEVI), derived from the newly available Moderate Resolution Imaging Spectroradiometer (MODIS)/Multi-Angle Implementation of Atmospheric Correction algorithm (MAIAC) product, from 2003 to 2016, which is indicative of forest's photosynthetic capacity. We estimated that 46% of the Brazilian Amazon biome was under severe to extreme drought in 2015/2016 as measured by the SPI, compared with 16% and 8% for the 2009/2010 and 2004/2005 droughts, respectively. The most recent drought (2015/2016) affected the largest area since the drought of 1981. Droughts tend to increase the variance of the photosynthetic capacity of Amazonian forests as based on the minimum and maximum AEVI analysis. However, the area showing a reduction in photosynthetic capacity prevails in the signal, reaching more than 400 000 km 2 of forests, four orders of magnitude larger than areas with AEVI enhancement. Moreover, the intensity of the negative AEVI steadily increased from 2005 to 2016. These results indicate that during the analysed period drought impacts were being exacerbated through time. Forests in the twenty-first century are becoming more vulnerable to droughts, with larger areas intensively and negatively responding to water shortage in the region. This article is part of a discussion meeting issue ‘The impact of the 2015/2016 El Niño on the terrestrial tropical carbon cycle: patterns, mechanisms and implications’.

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  • Drought regimes are intensifying across the region, possibly due to deforestation that continues to expand within the system.

    “Drought regimes are intensifying across the region41, possibly due to deforestation42 that continues to expand within the system (Extended Data Fig. 5).”

    From Critical transitions in the Amazon forest system (2024) · cites this paper as [41]

    The Discussion (section 4(a)) says increasing dry and very dry events appear to be occurring in southern Amazonia, but explicitly says the proposed broader trend toward more frequent and intense droughts is not supported by its observed long-term patterns in other regions. The Conclusion (section 5) likewise reports wetter conditions in some regions and no increase in drought intensity or duration in central areas. Citation 41 is attached to the region-wide drought claim, not the separate deforestation claim attached to citation 42. (LLM, conf=0.86)

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Authors
Anderson, L. O., Ribeiro Neto, G., Cunha, A. P., Fonseca, M. G., Mendes de Moura, Y., Dalagnol, R., Wagner, F. H., & de Aragão, L. E. O. E. C.
Affiliations
  • Centro Nacional de Monitoramento e Alertas de Desastres Naturais (BR)
  • National Centre for Monitoring and Early Warning of Natural Disasters—Cemaden, Ministry of Science, Technology, Innovation and Communication MCTIC, Brazil, Estrada Doutor Altino Bondesan, 500 - Distrito de Eugênio de Melo, São José dos Campos CEP:12.247-016, Brazil
  • Instituto Nacional de Pesquisas Espaciais (BR)
  • Department of Biological Sciences, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
  • National Institute for Space Research – INPE, Brazil, Remote Sensing Division, Av. Dos Astronautas 1758, Jardim da Granja, São José dos Campos/SP CEP:12.227-010, Brazil
Corresponding author
Anderson, Liana Oighenstein
ORCID
Venue
Philosophical Transactions of the Royal Society B: Biological Sciences
Publisher
The Royal Society
Published
2018-10-08
Volume
373
Issue
1760
Pages
20170411
ISSN
  • 0962-8436 (ISSN-L)
  • 1471-2970
DOI
10.1098/rstb.2017.0411
PMC
PMC6178446
OpenAlex
W2896921795
Cited by
148
References
3
Citations by year
2026: 15 · 2025: 10 · 2024: 20 · 2023: 31 · 2022: 27 · 2021: 30 · 2020: 5 · 2019: 8 · 2018: 2
FWCI
6.34
Type
journal article
Language
en
Open access
Licence
royalsociety.org/journals/ethics-policies/data-sharing-mining/ (tdm)
Locations
  • Philosophical Transactions of the Royal Society B Biological Sciences (publishedVersion)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Lancaster EPrints (Lancaster University) (submittedVersion)
  • Biblioteca Digital da Memória Científica do INPE (National Institute for Space Research) (submittedVersion)
Funders
  • Royal Society/Newton International Fellowship (NF170036)
  • Brazilian National Council for Scientific and Technological Development (309247/2016-0)
  • São Paulo Research Foundation (15/50484-0 ; 16/17652-9 ; 2015/22987-7 ; 2017/1525)
Topics
  • Physical Sciences › Environmental Science › Global and Planetary Change › Plant Water Relations and Carbon Dynamics
  • Physical Sciences › Environmental Science › Global and Planetary Change › Hydrology and Drought Analysis
  • Physical Sciences › Environmental Science › Ecology › Remote Sensing in Agriculture
Keywords
Amazon rainforest, drought vulnerability, recurrent drought, 2015-2016 El Niño, vegetation water stress, Standardized Precipitation Index, human-modified forests
MeSH terms
Brazil, Photosynthesis, Trees, Droughts, Climate Change, El Nino-Southern Oscillation, Satellite Imagery, Forests

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