Spatial organization of vegetation arising from non-local excitation with local inhibition in tropical rainforests

Sally Thompson, Gabriel Katul, John Terborgh, Patricia Alvarez-Loayza

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The Janzen-Connell (JC) effect, which hypothesizes that recruitment and growth of seedlings is positively correlated to the distance from the parent tree, is shown to generate highly organized vegetation biomass spatial patterns when coupled to a revised Fisher-Kolmogorov (FK) equation. Spatial organization arises through a novel mechanism of non-local activation and local inhibition. Over a single generation, the revised FK model calculations predict a "hen and chicks" dynamic pattern with mature trees surrounded by new seedlings growing at characteristic spatial distances in agreement with field data. Over longer timescales, the importance of stochastic dynamics, such as those associated with randomly occurring light gaps, increase thereby causing a substantial deviation between predictions from the deterministic FK model and its stochastic counterpart derived to account for such random disturbances. At still longer timescales, however, statistical measures of the spatial organization, specifically the spatial density of mature trees and their minimum spacing, converge between these two model representations. (C) 2009 Elsevier B.V. All rights reserved.

Original languageEnglish
Pages (from-to)1061-1067
Number of pages7
JournalPhysica D-Nonlinear Phenomena
Volume238
Issue number13
DOIs
Publication statusPublished - 15 Jun 2009
Externally publishedYes

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