The global abundance of tree palms
Robert Muscarella, Thaíse Emilio, Oliver L. Phillips, Simon L. Lewis, Ferry Slik, William J. Baker, Thomas L. P. Couvreur, Wolf L. Eiserhardt, Jens‐Christian Svenning, Kofi Affum‐Baffoe, Shin‐ichiro Aiba, Everton C. de Almeida, Samuel Almeida, Edmar Almeida de Oliveira, Esteban Álvarez‐Dávila, Luciana F. Alves, Carlos Mariano Alvez‐Valles, Fabrício Alvim Carvalho, Fernando Alzate Guarín, Ana Andrade, Luis E. O. C. Aragão, Alejandro Araujo Murakami, Luzmila Arroyo, Peter S. Ashton, Gerardo A. Aymard C., Timothy R. Baker, Plínio Barbosa de Camargo, Jos Barlow, Jean‐François Bastin, Natacha Nssi Bengone, Érika Berenguer, Nicholas Berry, Lilian Blanc, Katrin Böhning‐Gaese, Damien Bonal, Frans Bongers, Matt Bradford, Fabian Brambach, Francis Q. Brearley, Steven W. Brewer, José Luís Camargo, David G. Campbell, Carolina V. Castilho, Wendeson Castro, Damien Catchpole, Carlos E. Cerón Martínez, Shengbin Chen, Phourin Chhang, Percival Cho, Wanlop Chutipong, Connie J. Clark, Murray Collins, James A. Comiskey, Massiel Nataly Corrales Medina, Flávia R. C. Costa, Heike Culmsee, Heriberto David‐Higuita, Priya Davidar, Jhon del Águila Pasquel, Géraldine Derroire, Anthony Di Fiore, Tran Van Do, Jean‐Louis Doucet, Aurélie Dourdain, Donald R. Drake, Andreas Enßlin, Terry L. Erwin, Corneille E. N. Ewango, Robert M. Ewers, Sophie Fauset, Ted R. Feldpausch, Joice Ferreira, Leandro Valle Ferreira, Markus Fischer, Janet Franklin, Gabriella M. Fredriksson, Thomas W. Gillespie, Martin Gilpin, Christelle Gonmadje, Arachchige Upali Nimal Gunatilleke, Khalid Rehman Hakeem, Jefferson S. Hall, Keith C. Hamer, David J. Harris, Rhett D. Harrison, Andy Hector, Andreas Hemp, Bruno Hérault, Gabriel Hidalgo Pizango, Eurídice N. Honorio Coronado, Wannes Hubau, Mohammad Shah Hussain, Faridah Ibrahim, Nobuo Imai, Carlos Alfredo Joly, Shijo Joseph, K. Anitha, Kuswata Kartawinata, Justin Kassi, Timothy J. Killeen
Abstract
Abstract Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.