Mechanisms of long-distance dispersal of seeds by wind.


Journal Article

Long-distance dispersal (LDD) is central to species expansion following climate change, re-colonization of disturbed areas and control of pests. The current paradigm is that the frequency and spatial extent of LDD events are extremely difficult to predict. Here we show that mechanistic models coupling seed release and aerodynamics with turbulent transport processes provide accurate probabilistic descriptions of LDD of seeds by wind. The proposed model reliably predicts the vertical distribution of dispersed seeds of five tree species observed along a 45-m high tower in an eastern US deciduous forest. Simulations show that uplifting above the forest canopy is necessary and sufficient for LDD, hence, they provide the means to define LDD quantitatively rather than arbitrarily. Seed uplifting probability thus sets an upper bound on the probability of long-distance colonization. Uplifted yellow poplar seeds are on average lighter than seeds at the forest floor, but also include the heaviest seeds. Because uplifting probabilities are appreciable (as much as 1 5%), and tree seed crops are commonly massive, some LDD events will establish individuals that can critically affect plant dynamics on large scales.

Full Text

Duke Authors

Cited Authors

  • Nathan, R; Katul, GG; Horn, HS; Thomas, SM; Oren, R; Avissar, R; Pacala, SW; Levin, SA

Published Date

  • July 2002

Published In

Volume / Issue

  • 418 / 6896

Start / End Page

  • 409 - 413

PubMed ID

  • 12140556

Pubmed Central ID

  • 12140556

Electronic International Standard Serial Number (EISSN)

  • 1476-4687

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/nature00844


  • eng