PARENT SESSION
Contributed Oral Session 138: Fire and Vegetation Dynamics
Thursday, August 11, 1:30 PM - 5:00 PM, Meeting Room 519 B, Level 5, Palais des congrès de Montréal
Responses of rare plant species to fire across Floridas fire-adapted communities.
Gordon, Doria*,1, Slapcinsky, Jodi1, Menges, Eric2, 1 The Nature Conservancy, Gainesville, Florida, USA2 Archbold Biological Station, Lake Placid, Florida, USA
ABSTRACT- Lightning- and human-ignited fires have shaped many of Floridas natural communities. Persistence in these habitats requires adaptation to high temperatures and tissue loss or avoidance of these conditions through survival in unburned patches. Limited distribution of many rare species in increasingly fragmented habitats decreases the probability that chance avoidance will ensure long-term viability. We have monitored over 30 rare species for up to 14 years in sandhill, scrub, scrubby flatwoods, seepage, and pine rockland communites across Florida. Across a number of life history variables, including cover, density, frequency, flowering, seed production, and recruitment, 97% of these species responded positively (56%) or neutrally (41%) to fire. Only one species showed population declines following fire. Strategies for tolerating fire varied from adult mortality coupled with high seedling recruitment following fire to high survival and stimulated seed production. Timing of the response may be delayed for several years post-fire, suggesting that monitoring has been insufficiently long for understanding of population dynamics in some species. However, absence of fire appears to pose a more critical threat to persistence of these rare species than does its presence.
Key words: fire, rare plants, Florida, monitoring