A spatial model of tree α-diversity and tree density for the Amazon


Journal Article

Large-scale patterns of Amazonian biodiversity have until now been obscured by a sparse and scattered inventory record. Here we present the first comprehensive spatial model of tree α-diversity and tree density in Amazonian rainforests, based on the largest-yet compilation of forest inventories and bolstered by a spatial interpolation technique that allows us to estimate diversity and density in areas that have never been inventoried. These data were then compared to continent-wide patterns of rainfall seasonality. We find that dry season length, while only weakly correlated with average tree α-diversity, is a strong predictor of tree density and of maximum tree α-diversity. The most diverse forests for any given DSL are concentrated in a narrow latitudinal band just south of the equator, while the least diverse forests for any given DSL are found in the Guayana Shield and Amazonian Bolivia. Denser forests are more diverse than sparser forests, even when we used a measure of diversity that corrects for sample size. We propose that rainfall seasonality regulates tree α-diversity and tree density by affecting shade tolerance and subsequently the number of different functional types of trees that can persist in an area.

Full Text

Duke Authors

Cited Authors

  • Ter Steege, H; Pitman, N; Sabatier, D; Castellanos, H; Van Der Hout, P; Daly, DC; Silveira, M; Phillips, O; Vasquez, R; Van Andel, T; Duivenvoorden, J; De Oliveira, AA; Ek, R; Lilwah, R; Thomas, R; Van Essen, J; Baider, C; Maas, P; Mori, S; Terborgh, J; Vargas, PN; Mogollón, H; Morawetz, W

Published Date

  • November 1, 2003

Published In

Volume / Issue

  • 12 / 11

Start / End Page

  • 2255 - 2277

International Standard Serial Number (ISSN)

  • 0960-3115

Digital Object Identifier (DOI)

  • 10.1023/A:1024593414624

Citation Source

  • Scopus