%0 Journal Article
%A Gatti, Roberto Cazzolla
%A Reich, Peter B
%A Gamarra, Javier GP
%A Crowther, Tom
%A Hui, Cang
%A Morera, Albert
%A Bastin, Jean-Francois
%A de-Miguel, Sergio
%A Nabuurs, Gert-Jan
%A Svenning, Jens-Christian
%A Serra-Diaz, Josep M
%A Merow, Cory
%A Enquist, Brian
%A Kamenetsky, Maria
%A Lee, Junho
%A Zhu, Jun
%A Fang, Jinyun
%A Jacobs, Douglass F
%A Pijanowski, Bryan
%A Banerjee, Arindam
%A Giaquinto, Robert A
%A Alberti, Giorgio
%A Almeyda Zambrano, Angelica Maria
%A Alvarez-Davila, Esteban
%A Araujo-Murakami, Alejandro
%A Avitabile, Valerio
%A Aymard, Gerardo A
%A Balazy, Radomir
%A Baraloto, Chris
%A Barroso, Jorcely G
%A Bastian, Meredith L
%A Birnbaum, Philippe
%A Bitariho, Robert
%A Bogaert, Jan
%A Bongers, Frans
%A Bouriaud, Olivier
%A Brancalion, Pedro HS
%A Brearley, Francis Q
%A Broadbent, Eben North
%A Bussotti, Filippo
%A Castro da Silva, Wendeson
%A Gomes Cesar, Ricardo
%A Cesljar, Goran
%A Moscoso, Victor Chama
%A Chen, Han YH
%A Cienciala, Emil
%A Clark, Connie J
%A Coomes, David A
%A Dayanandan, Selvadurai
%A Decuyper, Mathieu
%A Dee, Laura E
%A Del Aguila Pasquel, Jhon
%A Derroire, Geraldine
%A Djuikouo, Marie Noel Kamdem
%A Tran, Van Do
%A Dolezal, Jiri
%A Dordevic, Ilija D
%A Engel, Julien
%A Fayle, Tom M
%A Feldpausch, Ted R
%A Fridman, Jonas K
%A Harris, David J
%A Hemp, Andreas
%A Hengeveld, Geerten
%A Herault, Bruno
%A Herold, Martin
%A Ibanez, Thomas
%A Jagodzinski, Andrzej M
%A Jaroszewicz, Bogdan
%A Jeffery, Kathryn J
%A Johannsen, Vivian Kvist
%A Jucker, Tommaso
%A Kangur, Ahto
%A Karminov, Victor N
%A Kartawinata, Kuswata
%A Kennard, Deborah K
%A Kepfer-Rojas, Sebastian
%A Keppel, Gunnar
%A Khan, Mohammed Latif
%A Khare, Pramod Kumar
%A Kileen, Timothy J
%A Kim, Hyun Seok
%A Korjus, Henn
%A Kumar, Amit
%A Kumar, Ashwani
%A Laarmann, Diana
%A Labriere, Nicolas
%A Lang, Mait
%A Lewis, Simon L
%A Lukina, Natalia
%A Maitner, Brian S
%A Malhi, Yadvinder
%A Marshall, Andrew R
%A Martynenko, Olga V
%A Mendoza, Abel L Monteagudo
%A Ontikov, Petr V
%A Ortiz-Malavasi, Edgar
%A Camacho, Nadir C Pallqui
%A Paquette, Alain
%A Park, Minjee
%A Parthasarathy, Narayanaswamy
%A Peri, Pablo Luis
%A Petronelli, Pascal
%A Pfautsch, Sebastian
%A Phillips, Oliver L
%A Picard, Nicolas
%A Piotto, Daniel
%A Poorter, Lourens
%A Poulsen, John R
%A Pretzsch, Hans
%A Ramirez-Angulo, Hirma
%A Correa, Zorayda Restrepo
%A Rodeghiero, Mirco
%A Gonzales, Rocio Del Pilar Rojas
%A Rolim, Samir G
%A Rovero, Francesco
%A Rutishauser, Ervan
%A Saikia, Purabi
%A Salas-Eljatib, Christian
%A Schepaschenko, Dmitry
%A Scherer-Lorenzen, Michael
%A Seben, Vladimir
%A Silveira, Marcos
%A Slik, Ferry
%A Sonke, Bonaventure
%A Souza, Alexandre F
%A Sterenczak, Krzysztof Jan
%A Svoboda, Miroslav
%A Taedoumg, Hermann
%A Tchebakova, Nadja
%A Terborgh, John
%A Tikhonova, Elena
%A Torres-Lezama, Armando
%A van der Plas, Fons
%A Vasquez, Rodolfo
%A Viana, Helder
%A Vibrans, Alexander C
%A Vilanova, Emilio
%A Vos, Vincent A
%A Wang, Hua-Feng
%A Westerlund, Bertil
%A White, Lee JT
%A Wiser, Susan K
%A Zawila-Niedzwiecki, Tomasz
%A Zemagho, Lise
%A Zhu, Zhi-Xin
%A Zo-Bi, Irie C
%A Liang, Jingjing
%D 2022
%F discovery:10149177
%I NATL ACAD SCIENCES
%J Proceedings of The National Academy of Sciences of the United States of America (PNAS)
%K Science & Technology, Multidisciplinary Sciences, Science & Technology - Other Topics, biodiversity, forests, hyperdominance, rarity, richness, BIODIVERSITY, RICHNESS, DIVERSITY, SAMPLE, PATTERNS, HETEROGENEITY, COMPLETENESS, ABUNDANCE, COVERAGE, ECOLOGY
%N 6
%T The number of tree species on Earth
%U https://discovery.ucl.ac.uk/id/eprint/10149177/
%V 119
%X One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness.
%Z This work is licensed under a Creative Commons Attribution 4.0 International License. The images  or other third-party material in this article are included in the Creative Commons license,  unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,  users will need to obtain permission from the license holder to reproduce the material. To view a copy of this  license, visit http://creativecommons.org/licenses/by/4.0/