Post-Fire Growth Strategies of Resprouting Florida Scrub Vegetation

[摘要] Although resprouting is recognized as a key post-disturbance response for plants, few studies have closely examined post-fire growth responses of resprouting species. Following a prescribed burn in Florida scrub, we compared intraspecific and interspecific growth patterns of 16 resprouting shrub species. We then examined how resprouting growth is related to species life history strategies to understand how the resprouting response could contribute to niche differentiation and species coexistence. We defined growth by calculating relative growth rates based on height, crown area, and crown volume of resprouts. In addition, we measured the number, diameter, and height of all resprouting stems. The number and diameter of all stems present before fire were also estimated. The number of resprouting stems after the fire was higher than the number of stems present before the fire for all species. As expected, species varied significantly in their post-fire growth rates, especially between those with differing recovery modes. Resprouting shrubs that are also post-fire seeders had the lowest growth rates compared to those that resprout and grow clonally, those that only resprout, and palmettos. We also found differences in post-fire growth among species with different growth forms, with palmettos having the fastest growth, followed by shrubs, and then by sub-shrubs. Within species, tradeoffs were found between height and the density of new stems, but not between height and diameter of re-sprouting stems. Overall, Florida scrub species exhibit a continuum of post-fire growth rates, suggesting the coexistence of a number of successful strategies for post-fire re-sprouting rather than a single optimal recovery strategy.

[学科分类] 生态、进化、行为和系统

[关键词] ericaceous shrubs;fire;Florida scrub;life history strategies;oaks;palmettos;resprouter