title: Temporal variability of forest communities: empirical estimates of population change in 4000 tree species.
abstract: Long-term surveys of entire communities of species are needed to measure fluctuations in natural populations and elucidate the mechanisms driving population dynamics and community assembly. We analysed changes in abundance of over 4000 tree species in 12 forests across the world over periods of 6-28 years. Abundance fluctuations in all forests are large and consistent with population dynamics models in which temporal environmental variance plays a central role. At some sites we identify clear environmental drivers, such as fire and drought, that could underlie these patterns, but at other sites there is a need for further research to identify drivers. In addition, cross-site comparisons showed that abundance fluctuations were smaller at species-rich sites, consistent with the idea that stable environmental conditions promote higher diversity. Much community ecology theory emphasises demographic variance and niche stabilisation; we encourage the development of theory in which temporal environmental variance plays a central role.
authors.affiliation: Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón, Republic of Panamá; Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
authors.forename: Ryan A
authors.initials: RA
authors.lastname: Chisholm
authors.forename: Richard
authors.initials: R
authors.lastname: Condit
authors.forename: K Abd
authors.initials: KA
authors.lastname: Rahman
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Baker
authors.forename: Sarayudh
authors.initials: S
authors.lastname: Bunyavejchewin
authors.forename: Yu-Yun
authors.initials: YY
authors.lastname: Chen
authors.forename: George
authors.initials: G
authors.lastname: Chuyong
authors.forename: H S
authors.initials: HS
authors.lastname: Dattaraja
authors.forename: Stuart
authors.initials: S
authors.lastname: Davies
authors.forename: Corneille E N
authors.initials: CE
authors.lastname: Ewango
authors.forename: C V S
authors.initials: CV
authors.lastname: Gunatilleke
authors.forename: I A U
authors.initials: IA
authors.lastname: Nimal Gunatilleke
authors.forename: Stephen
authors.initials: S
authors.lastname: Hubbell
authors.forename: David
authors.initials: D
authors.lastname: Kenfack
authors.forename: Somboon
authors.initials: S
authors.lastname: Kiratiprayoon
authors.forename: Yiching
authors.initials: Y
authors.lastname: Lin
authors.forename: Jean-Remy
authors.initials: JR
authors.lastname: Makana
authors.forename: Nantachai
authors.initials: N
authors.lastname: Pongpattananurak
authors.forename: Sandeep
authors.initials: S
authors.lastname: Pulla
authors.forename: Ruwan
authors.initials: R
authors.lastname: Punchi-Manage
authors.forename: Raman
authors.initials: R
authors.lastname: Sukumar
authors.forename: Sheng-Hsin
authors.initials: SH
authors.lastname: Su
authors.forename: I-Fang
authors.initials: IF
authors.lastname: Sun
authors.forename: H S
authors.initials: HS
authors.lastname: Suresh
authors.forename: Sylvester
authors.initials: S
authors.lastname: Tan
authors.forename: Duncan
authors.initials: D
authors.lastname: Thomas
authors.forename: Sandra
authors.initials: S
authors.lastname: Yap
mesh_terms: D004777:Environment; D008954:Models, Biological; D011157:Population Dynamics; D013997:Time Factors; D014197:Trees / Q000502:physiology*
keywords: Abundance fluctuations; biodiversity; demographic stochasticity; environmental variance; forest dynamics; neutral theory; niche stabilization