DOI: 10.15146/r3mm4v
title: Tree species abundance through time in tropical forest census plots, Panama

description: All trees at least 1 cm diameter at breast height were censused in three
 sites in Panama. The Barro Colorado plot is 50 hectares in area and was
 fully censused on eight occasions between 1982 and 2015. The Sherman plot
 is 5.96 hectares and was fully censuses four times between
 1996 and 2009. The Cocoli plot is 4 hectares and was censused
 three times between 1994 and 1999. The three accompanying tables
 give the population size of living individuals of all species in every
 census at the three sites. 
description: Every individual was mapped, tagged, and identified if the
 diameter at 1.3 m above the ground was at least 1 cm. Individuals with
 multiple stems from one root base were counted as single trees. Every tree
 was identified with reference to herbarium specimens and published flora
 (especially T. Croat's <em>Flora of Barro Colorado Island
 </em>[Stanford, 1978]). Some trees were assigned into distinct
 morphotypes but could not be fully identified, and a small number of
 individuals were never identified. Methods are described in detail
 in Condit, R. [1998. Tropical Forest Census Plots: Methods and Results
 from Barro Colorado Island, Panama and a Comparison with Other Plots.
 Springer-Verlag, Berlin.]
description: Species names are current as of 2017. Two papers, Condit et al.
 (1996, 2004), list all species and their abundances in early
 censuses. Many tree species names have been changed since 1982, and a
 separate data
 archive (Condit et al. 2017) provides all past names, allowing
 the tables in the early papers to be linked to the tables here. Because we
 continually correct the data, exact counts reported in the early papers
 will not necessarily match those shown now. In each
 plot, several taxa are flagged with asterisks. These are cases where the
 group of trees so named does not represent a single consistent species
 through time. As identifications evolved, two of the taxa were divided
 into two species. At that time, any trees that had already died could not
 be identified using the updated criteria. The counts of these marked
 species thus cannot be interpreted as changing abundance through time.
 There were also a number of individuals that were never identified before
 they died, and the unidentified category is thus flagged with an
 asterisk. Species labeled
 as <em>sp.</em> and lacking a taxonomic authority were
 morphospecies. They were trees assigned distinct categories based on leaf,
 bark, flower, or fruit form but never identified. Several of these
 morphospecies from the 1982 were finally identified later, but several
 remain and are in the tables. Their counts represent changing abundance
 through time of individual species; we just do not have a Latin name
 assigned. All other taxa, those not flagged with
 asterisks, represent single, consistently-identified tree species. Their
 counts represent change in abundance through time. To standardize a
 density per unit area, each count must be divided by the size of the
 plot: 50 ha at Barro Colorado, 4 ha at Cocoli, and 5.96 ha at
 Sherman.   Citations
 Condit, R., Hubbell, S. P., and Foster, R. B. 1996. Changes in
 tree species abundance in a neotropical forest: impact of climate change.
 Journal of Tropical Ecology 12:231–256.  Condit, R.,
 Aguilar, S., Hernandez, A., Pérez, R., Lao, S., Angehr, G., Hubbell, S.,
 and Foster, R. 2004. Tropical forest dynamics across a rainfall gradient
 and the impact of an El Niño dry season. Journal of Tropical Ecology
 20:51–72. R. Condit, S. Aguilar, R. Pérez. S. Lao, S.
 P. Hubbell, R. B. Foster. 2017. BCI 50-ha Plot Taxonomy as of 2017. DOI
 https://doi.org/10.25570/stri/10088/32990.