Mapping tree density at a global scale.
The global extent and distribution of forest trees is central to our understanding of the terrestrial biosphere. We provide the first spatially continuous map of forest tree density at a global scale. This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate. Of these trees, approximately 1.39 trillion exist in tropical and subtropical forests, with 0.74 trillion in boreal regions and 0.61 trillion in temperate regions. Biome-level trends in tree density demonstrate the importance of climate and topography in controlling local tree densities at finer scales, as well as the overwhelming effect of humans across most of the world. Based on our projected tree densities, we estimate that over 15 billion trees are cut down each year, and the global number of trees has fallen by approximately 46% since the start of human civilization.
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Crowther
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Glick
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Covey
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Bettigole
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Maynard
Department of Environmental Sciences, University of Helsinki, Helsinki 00014, Finland.
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Thomas
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Smith
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Hintler
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Duguid
Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06511, USA.
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Amatulli
Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06511, USA.
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Tuanmu
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.|Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut 06511, USA.|Department of Life Sciences, Silwood Park, Imperial College, London SL5 7PY, UK.
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Jetz
Departamento de Ciencias Forestales, Universidad de La Frontera, Temuco 4811230, Chile.
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Salas
RedCastle Resources, Salt Lake City, Utah 84103, USA.
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Stam
Universidade Federal do Sul da Bahia, Ferradas, Itabuna 45613-204, Brazil.
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Piotto
Forestry Department, Food and Agriculture Organization of the United Nations, Rome 00153, Italy.
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Tavani
Operation Wallacea, Spilbsy, Lincolnshire PE23 4EX, UK.|Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation (SAC), University of Kent, Canterbury ME4 4AG, UK.
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Green
Operation Wallacea, Spilbsy, Lincolnshire PE23 4EX, UK.
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Bruce
Molecular Imaging Research Center MIRCen/CEA, CNRS URA 2210, 91401 Orsay Cedex, France.
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Williams
Landcare Research, Lincoln 7640, New Zealand.
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SK
Wiser
WSL, Swiss Federal Institute for Forest, Snow and Landscape Research, 8903 Birmensdorf, Switzerland.
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MO
Huber
Environmental Science Group, Wageningen University &Research Centre, 6708 PB, The Netherlands.
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Hengeveld
Environmental Science Group, Wageningen University &Research Centre, 6708 PB, The Netherlands.
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GJ
Nabuurs
Center for Forest Ecology and Productivity RAS, Moscow 117997, Russia.
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Tikhonova
CEN Center for Earth System Research and Sustainability, Institute of Geography, University of Hamburg, Hamburg 20146, Germany.
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Borchardt
Department of Botany and Zoology, Masaryk University, Brno 61137, Czech Republic.
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Li
South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont 7735, South Africa.
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Powrie
Institute of Plant Sciences, Botanical Garden, and Oeschger Centre for Climate Change Research, University of Bern, 3013 Bern, Switzerland.|Senckenberg Gesellschaft für Naturforschung, Biodiversity and Climate Research Centre (BIK-F), 60325 Frankfurt, Germany.
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Fischer
Department of Plant Systematics, University of Bayreuth, 95447 Bayreuth, Germany.
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Hemp
Albrecht von Haller Institute of Plant Sciences, Georg August University of Göttingen, 37073 Göttingen, Germany.
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Homeier
Tropical Ecology Research Group, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
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Cho
Universidade Regional de Blumenau, Departamento de Engenharia Florestal, Blumenau/Santa Catarina 89030-000, Brazil.
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Vibrans
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Umunay
Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
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Piao
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Rowe
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Ashton
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Crane
Yale School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06511, USA.
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Bradford
D004463:Ecology / Q000706:statistics & numerical data; D017753:Ecosystem; D016468:Forestry / Q000706:statistics & numerical data; D065928:Forests; D062305:Geographic Mapping; D011156:Population Density; D015203:Reproducibility of Results; D014197:Trees / Q000254:growth & development*