Resiliency and response to hurricane disturbance in a tropical shrub, Ardisia escallonioides (Myrsinaceae), in south Florida

Abstract

The resiliency to hurricane disturbance and the response to posthurricane environmental conditions were examined in the tropical shrub Ardisia escallonioides (Myrsinaceae). Hurricane Andrew struck three of four study sites in subtropical hard-wood forests in south Florida on 24 August 1992. Posthurricane understory light levels in the disturbed sites ranged from 21 to 53% of full light in 1993 and remained high in 1994; in contrast, light levels averaged only 9% in the undisturbed forest. Significant differences in mortality, damage, and defoliation were observed among the three hurricane-damaged populations. Mortality was low, but adults suffered high levels of damage and defoliation. Following the hurricane, populations in the most severely disturbed forests had more growth than populations in lightly damaged or undamaged forests. Seed germination and seedling growth were not associated with light availability. No long-term seed dormancy was observed. The observed response to posthurricane environmental conditions is consistent with understory species that show release following canopy opening, but are able to persist under periods of canopy closure. The local dominance of this species in many coastal forests in south Florida may be due to the high frequency of hurricane disturbance.