title: Floodplains as an Achilles' heel of Amazonian forest resilience.
abstract: The massive forests of central Amazonia are often considered relatively resilient against climatic variation, but this view is challenged by the wildfires invoked by recent droughts. The impact of such fires that spread from pervasive sources of ignition may reveal where forests are less likely to persist in a drier future. Here we combine field observations with remotely sensed information for the whole Amazon to show that the annually inundated lowland forests that run through the heart of the system may be trapped relatively easily into a fire-dominated savanna state. This lower forest resilience on floodplains is suggested by patterns of tree cover distribution across the basin, and supported by our field and remote sensing studies showing that floodplain fires have a stronger and longer-lasting impact on forest structure as well as soil fertility. Although floodplains cover only 14% of the Amazon basin, their fires can have substantial cascading effects because forests and peatlands may release large amounts of carbon, and wildfires can spread to adjacent uplands. Floodplains are thus an Achilles' heel of the Amazon system when it comes to the risk of large-scale climate-driven transitions.
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Environmental Science Department, Wageningen University, 6700 AA Wageningen, The Netherlands; mflores.bernardo@gmail.com marten.scheffer@wur.nl.|Resource Ecology Group, Wageningen University, 6700 AA Wageningen, The Netherlands.|Ecology Department, Centre for Biosciences, Federal University of Rio Grande do Norte, 59072-970 Natal, RN, Brazil.
authors.forename: Bernardo M
authors.initials: BM
authors.lastname: Flores
authors.affiliation: Resource Ecology Group, Wageningen University, 6700 AA Wageningen, The Netherlands.
authors.forename: Milena
authors.initials: M
authors.lastname: Holmgren
authors.affiliation: School of Life Sciences, Nanjing University, Nanjing 210023, China.
authors.forename: Chi
authors.identifier: 0000-0002-1841-9032
authors.initials: C
authors.lastname: Xu
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Environmental Science Department, Wageningen University, 6700 AA Wageningen, The Netherlands.
authors.forename: Egbert H
authors.initials: EH
authors.lastname: van Nes
authors.affiliation: Forest Ecology and Forest Management Group, Wageningen University, 6700 AA Wageningen, The Netherlands.
authors.forename: Catarina C
authors.initials: CC
authors.lastname: Jakovac
authors.affiliation: National Institute for Amazonian Research, 69083-000 Manaus, Brazil.
authors.forename: Rita C G
authors.initials: RCG
authors.lastname: Mesquita
authors.affiliation: Aquatic Ecology and Water Quality Management Group, Environmental Science Department, Wageningen University, 6700 AA Wageningen, The Netherlands; mflores.bernardo@gmail.com marten.scheffer@wur.nl.
authors.forename: Marten
authors.initials: M
authors.lastname: Scheffer
mesh_terms: D000383:Agriculture; D057231:Climate Change; D005390:Fires; D055868:Floods; D065928:Forests; D055593:Geological Phenomena
keywords: climate change; drought; fire; tropical forest; tropical savanna