Ecological Research

, Volume 24, Issue 1, pp 225–230 | Cite as

Intensive research activity alters short-term seedling dynamics in a tropical forest

  • Liza S. Comita
  • Gregory R. Goldsmith
  • Stephen P. Hubbell
Note and Comment


Researchers can have unintentional, yet significant effects on their study systems. We tested for the effects of an intensive tree census on seedling dynamics in a 50-ha permanent forest plot on Barro Colorado Island, Panama. At the community level, and for different shade-tolerance guilds, we found no significant differences in seedling recruitment or survival inside compared to controls outside the plot. However, among growth forms, canopy trees and lianas exhibited significantly lower seedling survival inside the plot. Results suggest that intense researcher activity impacts short-term vegetation dynamics, but effects do not accumulate over time.


Disturbance Forest dynamics plot Long-term ecological research Research impact Trampling 



We thank Leslie Morefield, Salomon Aguilar, Blexein Contreras, and the BCI plot crew for assisting with the seedling censuses. Valuable comments were provided by Sarah Batterman and Adam Roddy. Funding for this research was provided by a U.S. National Science Foundation grant (award number 0075102) and Research Experience for Undergraduates (REU) supplemental grant. L. Comita acknowledges the support of an NSF Graduate Research Fellowship and a University of Georgia Presidential Fellowship. Logistical support was provided by the University of Georgia, the Center for Tropical Forest Science and the Smithsonian Tropical Research Institute.


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Copyright information

© The Ecological Society of Japan 2008

Authors and Affiliations

  • Liza S. Comita
    • 1
    • 5
  • Gregory R. Goldsmith
    • 2
    • 6
  • Stephen P. Hubbell
    • 3
    • 4
    • 7
  1. 1.Department of Plant BiologyUniversity of GeorgiaAthensUSA
  2. 2.Department of BiologyBowdoin CollegeBrunswickUSA
  3. 3.Department of Plant BiologyUniversity of GeorgiaAthensUSA
  4. 4.Smithsonian Tropical Research InstituteBalbaoRepublic of Panama
  5. 5.Department of Ecology, Evolution, and Environmental BiologyColumbia UniversityNew YorkUSA
  6. 6.Department of Integrative BiologyUniversity of California BerkeleyBerkeleyUSA
  7. 7.Department of Ecology and Evolutionary BiologyUniversity of CaliforniaLos AngelesUSA

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