Different mechanisms have been proposed to explain how vertical and horizontal heterogeneity in light conditions enhances tree species coexistence in forest ecosystems. The foliage partitioning theory proposes that differentiation in vertical foliage distribution, caused by an interspecific variation in mortality-to-growth ratio, promotes stable coexistence. In contrast, successional niche theory posits that horizontal light heterogeneity, caused by gap dynamics, enhances species coexistence through an interspecific trade-off between growth rate and survival. To distinguish between these theories of species coexistence, we analyzed tree inventory data for 370 species from the 50-ha plot in Pasoh Forest Reserve, Malaysia. We used community-wide Bayesian models to quantify size-dependent growth rate and mortality of every species. We compared the observed size distributions and the projected distributions from size-dependent demographic rates. We found that the observed size distributions were not simply correlated with the rate of population increase but were related to demographic properties such as size growth rate and mortality. Species with low relative abundance of juveniles in size distribution showed high growth rate and low mortality at small tree sizes and low per-capita recruitment rate. Overall, our findings were in accordance with those predicted by foliage partitioning theory.
Data for 370 species in actual community
Tree diameter data of 370 selected tree species in the Pasoh 50-ha plot in 1990 and 2000 census. Species names are kept unchanged (the "actual community"). The provided dataset is a processed subset of the original dataset for our demographic analysis of tree size distribution and demography of tree species populations demonstrated in the main paper. Readers interested in using the data for purposes other than testing our analysis are advised to obtain the raw data of tree inventories of the Pasoh 50-ha plot from the Forest Research Institute Malaysia (FRIM), the National Institute for Environmental Studies (NIES), Japan, and the Center for Tropical Forest Science (CTFS), Smithsonian Tropical Research Institute.
dfr100.txt
Data for 370 species in permuted community
Tree diameter data of 370 selected tree species in the Pasoh 50-ha plot in 1990 and 2000 census. In this data, species identity of each tree was shuffled to generate a fake, "permuted community". The provided dataset is a processed subset of the original dataset for our demographic analysis of tree size distribution and demography of tree species populations demonstrated in the main paper. Readers interested in using the data for purposes other than testing our analysis are advised to obtain the raw data of tree inventories of the Pasoh 50-ha plot from the Forest Research Institute Malaysia (FRIM), the National Institute for Environmental Studies (NIES), Japan, and the Center for Tropical Forest Science (CTFS), Smithsonian Tropical Research Institute.
dfr100ps.txt
Species names of 370 species
List of species codes and scientific species names for 370 selected tree species in the Pasoh 50-ha plot in 1990 and 2000 census. The provided dataset is a processed subset of the original dataset for our demographic analysis of tree size distribution and demography of tree species populations demonstrated in the main paper. Readers interested in using the data for purposes other than testing our analysis are advised to obtain the raw data of tree inventories of the Pasoh 50-ha plot from the Forest Research Institute Malaysia (FRIM), the National Institute for Environmental Studies (NIES), Japan, and the Center for Tropical Forest Science (CTFS), Smithsonian Tropical Research Institute.
species_code.txt
R code for growth and mortality models
R code for parameter estimation of of size-growth function and mortality function, applied to the Bayesian analysis of tree dynamics in the Pasoh 50-ha plot.
r_code.txt