Survival of tree seedligns across space and time: estimates from long-term count dataAuthor(s): Brian Beckage; Michael Lavina; James S. Clark
Source: Journal of Ecology, Vol. 93: 1177-1184
Publication Series: Miscellaneous Publication
PDF: View PDF (788 KB)
Tree diversity in forests may be maintained by variability in seedling recruitment. Although forest ecologists have emphasized the importance of canopy gaps in generating spatial variability that might promote tree regeneration, the effects of canopy gaps on seedling recruitment may be offset by dense forest understories.
Large annual fluctuations in recruitment processes, coupled with the long life of forest trees, can provide an alternative mechanism for maintaining tree diversity. Evaluating the relative importance of spatial vs. temporal variability in recruitment, however, requires estimates of seedling survival that are extensive on both scales.
Estimates of survival derived from conventional statistical methods require that individual seedlings are monitored through time, and are therefore often limited in extent. We demonstrate a relatively fast and easy alternative approach to measuring survival that uses repeated counts of individuals in quadrats.
Annual seedling counts were used to quantify both the effects of small canopy gaps and understorey shrubs on the survival of Acer rubrum (red maple) seedlings and the magnitude of residual spatial and temporal variability in seedling survival.
We found that a dense understorey had a greater effect on seedling survival than did canopy gaps. Our canopy gaps had only a slight positive effect on seedling survival, and their benefit was offset by a large negative effect of the understorey shrub Rhododendron maximum.
Annual fluctuations in recruitment processes were seven times greater than spatial variability across transects and the effect of individual years on seedling survival was larger than even that of understorey shrubs.
The long life span of trees coupled with large annual variability in recruitment success across species may maintain the diversity of forest trees through a storage effect.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationBeckage, Brian; Lavina, Michael; Clark, James S. 2005. Survival of tree seedligns across space and time: estimates from long-term count data. Journal of Ecology, Vol. 93: 1177-1184
KeywordsAcer rubrum, Bayesian statistics, canopy gaps, forest dynamics, Rhododendron maximum, seedling survival, spatial variability, storage effect, temporal variability, tree diversity
- Seedling survival and growth of three forest tree species: The role of spatial heterogeneity
- Canopy accession strategies and climate-growth relationships in Acer Rubrum.
- Nonadditive effects of leaf litter species diversity on breakdown dynamics in a deteritus-bases stream
XML: View XML