© 2007 Heron Publishing—Victoria, Canada
A link between hurricane-induced tree sprouting, high stem density and short canopy in tropical dry forest
Skip J. Van Bloem (1, 2), Peter G. Murphy (3) and Ariel E. Lugo (4)
1. Department of Agronomy and Soils, University of Puerto Rico, Mayagüez, P.O. Box 9030, Mayagüez, PR 00681, USA / 2. Corresponding author (svanbloem@uprm.edu) / 3. Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA / 4. International Institute of Tropical Forestry, USDA Forest Service, Ceiba 1201, Jardín Botánico Sur, Río Piedras, PR 00926-1119,
USA / Received March 14, 2006; accepted June 20, 2006; published online December 1, 2006
Summary
The physiognomy of Caribbean dry forest is shorter, denser and contains a greater proportion of multi-stemmed trees than other
neotropical dry forests. Our previous research, conducted after Hurricane Georges in 1998, has shown that dry forest trees
sprout near the base following hurricane disturbance, even if the trees have not incurred structural damage. However, for
these hurricane-induced sprouts to contribute to the physiognomy of the forest, they must grow and survive. We followed sprout
dynamics and stem mortality on 1,407 stems from 1998, after Hurricane Georges, until 2005. The number of surviving sprouts
and the proportion of sprouting stems decreased during the 7-year period, but the sprouting rate was still 3-fold higher and
the proportion of sprouting stems 5-fold higher than before the hurricane. Mortality of non-sprouting stems (15.4%) was about
the same as for sprouting stems (13.9%) after 7 years. The mean length of the dominant sprout surpassed 1.6 m by 2005, with
over 13% of the dominant sprouts reaching subcanopy height. Sprout growth and survival varied among species. These results
demonstrate that, despite some thinning, hurricane-induced sprouts survive and grow and that the unique physiognomic characteristic
of Caribbean dry forests is related to hurricane disturbance.
Keywords:
disturbance, forest structure, growth, Guánica Forest, Puerto Rico, regeneration, stem mortality, wind.
