title: The response of tropical rainforests to drought-lessons from recent research and future prospects.
abstract: CONCLUSIONS
  We review the recent findings on the influence of drought on tree mortality, growth or ecosystem functioning in tropical rainforests. Drought plays a major role in shaping tropical rainforests and the response mechanisms are highly diverse and complex. The numerous gaps identified here require the international scientific community to combine efforts in order to conduct comprehensive studies in tropical rainforests on the three continents. These results are essential to simulate the future of these ecosystems under diverse climate scenarios and to predict the future of the global earth carbon balance.
  
  
  BACKGROUND
  Tropical rainforest ecosystems are characterized by high annual rainfall. Nevertheless, rainfall regularly fluctuates during the year and seasonal soil droughts do occur. Over the past decades, a number of extreme droughts have hit tropical rainforests, not only in Amazonia but also in Asia and Africa. The influence of drought events on tree mortality and growth or on ecosystem functioning (carbon and water fluxes) in tropical rainforest ecosystems has been studied intensively, but the response mechanisms are complex.
  
  
  OBJECTIVE
  Herein, we review the recent findings related to the response of tropical forest ecosystems to seasonal and extreme droughts and the current knowledge about the future of these ecosystems.
  
  
  RESULTS
  This review emphasizes the progress made over recent years and the importance of the studies conducted under extreme drought conditions or in through-fall exclusion experiments in understanding the response of these ecosystems. It also points to the great diversity and complexity of the response of tropical rainforest ecosystems to drought.
  
  
  CONCLUSIONS
  The numerous gaps identified here require the international scientific community to combine efforts in order to conduct comprehensive studies in tropical forest regions. These results are essential to simulate the future of these ecosystems under diverse climate scenarios and to predict the future of the global earth carbon balance.
authors.affiliation: INRA, UMR « Ecologie et Ecophysiologie Forestières », Université de Lorraine-INRA, F-54280 Champenoux, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Bonal
authors.affiliation: INRA, UMR «Ecologie des Forêts de Guyane», AgroParisTech-CIRAD-INRA-CNRS-Université de Guyane-Université des Antilles, Campus Agronomique, 97387 Kourou, Guyane Française France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Burban
authors.affiliation: CIRAD, UMR « Ecologie des Forêts de Guyane », AgroParisTech- CIRAD-INRA-CNRS-Université de Guyane-Université des Antilles, Campus Agronomique, 97387 Kourou, Guyane Française France ; University of Antwerpen, Campus Agronomique, 97387 Kourou, Guyane Française France.
authors.forename: Clément
authors.initials: C
authors.lastname: Stahl
authors.affiliation: National Institute for Space Research (INPE), São José dos Campos, SP 12227-010 Brazil.
authors.forename: Fabien
authors.initials: F
authors.lastname: Wagner
authors.affiliation: CIRAD, UMR « Ecologie des Forêts de Guyane », AgroParisTech- CIRAD-INRA-CNRS-Université de Guyane-Université des Antilles, Campus Agronomique, 97387 Kourou, Guyane Française France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Hérault
keywords: Carbon; Climate; Drought; Global change; Growth; Mortality; Soil; Tropical; Water