An Estimate of the Number of Species of Trees in an Amazonian Forest Community

Abstract

1. As many as 1482 trees 10 cm. or more in diameter, belonging to 179 species, have been counted on a 3.5-hectare plot in a virgin terra firme forest near Castanhal, Pará, Brazil. Evidence is given that the distribution of at least the common species over the territory of the plot is uniform, and the inference is drawn that about 70 species which may occur in the association sampled have not been encountered on the plot. 2. Comparison of the species composition of the sample described in the present paper with that on a plot some 120 km. away studied by Black et al. (1) shows very considerable differences. The number of species in the different facies of the terra firme association in Amazonia may be much larger than found in the samples studied so far.