FIRE REGIME OF THE OKEFENOKEE SWAMP AND ITS RELATION TO HYDROLOGICAL AND CLIMATIC CONDITIONS

A fire record of the Okefenokee Swamp National Wildlife Refuge during the period 1938-1989 was examined in this study. Frequency analysis in dicated that fires with burnt area 50% or more of the swamp area have return periods longer than 100 years, much longer than the previously assumed 20-25 year return period. Results of statistical analysis show ed that fire activity is significantly related to die water level of t he Okefenokee Swamp. Based on this relationship, a potential fire size can be estimated for a given water level. It seemed difficult to prov e the link between the fire activity in the Okefenokee Swamp and the E l Nino/Southern Oscillation (ENSO) events. However, further analysis r evealed that the hydrological condition of the swamp is significantly related to the ENSO events. During the warm events, the Okefenokee Swa mp area is wetter than normal; during the cold events, the area is dri er than normal, and major fires tend to occur. The investigation of th e fire regime may help achieve a better understanding of the effect of fires on the dynamics of this large complex ecosystem. The results ar e also useful for the refuge managers, especially in the mid- to long- term planning of fire management practices.