EGU General Assembly 2020
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Amazon forest responses to drought: scaling from individuals to ecosystems.

Scott R. Saleska1, Natalia Restrepo-Coupe1,2, Fernanda V. Barros3, Paulo R. L. Bittencourt3, Neill Prohaska1, Deliane V. Penha4, Loren P. Albert5, Mauro Brum1, Luciano Pereira3, Leila S. M. Leal12, Alessandro C. Araujo6, Scott C. Stark7, Luciana Alves8, Edgard Tribuzy4, Plinio B. Camargo9, Raimundo Cosme de Oliveira10, Valeriy Ivanov11, Jose Mauro4, Luiz Aragao13, and Rafael S. Oliveira3
Scott R. Saleska et al.
  • 1Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
  • 2School of Life Science, University of Technology Sydney, Sydney, NSW, Australia
  • 3Department of Plant Biology, Institute of Biology, CP 6109, University of Campinas – UNICAMP, 13083-970, Campinas, SP, Brazil
  • 4Universidade Federal do Oeste do Pará, Santarem, Para, Brazil
  • 5Institute at Brown for Environment and Society, Brown University, Providence, RI, USA
  • 6LBA Program Micrometeorology Group, INPA, Manaus, Amazonas, Brazil
  • 7Department of Forestry, Michigan State University, East Lansing, MI, USA
  • 8UCLA Institute of the Environment and Sustainability, University of Califormia Los Angeles, Los Angeles, CA, USA
  • 9Laboratório de Ecologia Isotópica, Centro de Energia Nuclear na Agricultura da Universidade de São Paulo, Piracicaba, SP, Brazil
  • 10Embrapa Amazônia Oriental, Santarem, PA, Brazil
  • 11Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI 48019, USA
  • 12Laboratory of Sustainable Systems Analyses, Oriental Amazon Embrapa, Belém, Pará, Brazil
  • 13College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom

Scaling from individuals or species to ecosystems is a fundamental challenge of modern ecology and understanding tropical forest response to drought is a key challenge of predicting responses to global climate change.  We here synthesize our developing understanding of these twin challenges by examining individual and ecosystem responses to the 2015 El Niño drought at two sites in the central Amazon of Brazil, near Manaus and Santarem, which span a precipitation gradient from moderate (Manaus) to long (Santarem) dry seasons.  We will focus on how ecosystem water and carbon cycling, measured by eddy flux towers, emerges from individual trait-based responses, including photosynthetic responses of individual leaves, and water cycle responses in terms of stomatal conductance and hydraulic xylem embolism resistance.  We found the Santarem forest (with long dry seasons) responded strongly to drought: sensible heat values significantly increased and evapotranspiration decreased.  Consistent with this, we also observed reductions in photosynthetic activity and ecosystem respiration, showing levels of stress not seen in the nearly two decades since measurements started at this site.  Forests at the Manaus site showed significant, however, less consistent reductions in water and carbon exchange and a more pronounced water deficit.  We report an apparent community level forest composition selecting for assemblies of traits and taxa manifest of higher drought tolerance at Santarem, compared to the Manaus forest (short dry seasons) and other forest sites across Amazonia.  These results suggest that we may be able to use community trait compositions (as selected by past climate conditions) and environmental threshold values (e.g. cumulative rainfall, atmospheric moisture and radiation) as to help forecast ecosystem responses to future climate change.

How to cite: Saleska, S. R., Restrepo-Coupe, N., Barros, F. V., Bittencourt, P. R. L., Prohaska, N., Penha, D. V., Albert, L. P., Brum, M., Pereira, L., Leal, L. S. M., Araujo, A. C., Stark, S. C., Alves, L., Tribuzy, E., Camargo, P. B., Cosme de Oliveira, R., Ivanov, V., Mauro, J., Aragao, L., and Oliveira, R. S.: Amazon forest responses to drought: scaling from individuals to ecosystems., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12746,, 2020