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Harvard Forest Symposium Abstract 2018

  • Title: Size, life history, and the division of resources in forests
  • Primary Author: John Grady (Bryn Mawr College)
  • Additional Authors: Brian Enquist (University of Arizona); Sean Michaletz (University of Arizona); Sydne Record (Bryn Mawr College)
  • Abstract:

    John Grady, Quentin Read, Nadja Ruger, Sydne Record, Phoebe Zarnetske, Alexander Shenkin, Sean Michaletz, Brian Enquist

    Body size and life history shape resource use, but linking individual rates to the division of resources at the community scale is challenging. Here, we quantified stand-level partitioning of light and carbon in a 45 ha primary forest in Panama with respect to tree size and life history. Approximate energy equivalence - equal energy use per size class - was observed at intermediate sizes, but declines occurred among saplings in the shaded understory, and large trees in the exposed, upper canopy. Shade-intolerant 'fast' (fast-growing, short-lived) and 'low' (low reproduction, long-lived) species dominated well-lit canopies, while shade tolerant 'slow' (slow-growing, long-lived) and 'high' (high reproduction, short-lived) forms dominated the dimmer understory. Our results indicate a stable, demographic cycling of life histories along an energy gradient, and suggest rules for how resource use scales from individuals to the community.

  • Research Category: Biodiversity Studies; Physiological Ecology, Population Dynamics, and Species Interactions