Print PageUnderstanding species responses to global change will help predict shifts in species distributions as well as aid in conservation. Spring events such as leaf unfolding and flowering are associated with changes in air temperature. Changes in the timing of seasonal activities of organisms over time may be the most responsive and easily observable indicator of environmental changes associated with global climate change. Organismal response to global climate change in subtropical ecosystems is rarely studied. In this study, we build upon past research where we documented delayed seasonal flowering among plants in Florida. Here we examine flowering response of closely related native and nonnative plant species pairs to changes in climate in Florida.
Results/Conclusions
Surprisingly, there were few differences in reproductive responses by closely-related pairs of native and nonnative plant species to climatic changes in Florida. In previous research, it has been demonstrated that nonnative species differentially track climate change. However, these studies have taken place in mid to higher latitudes. We argue that plants in Florida have different reproductive cues than those from more northern climates. The number of days below freezing has increased in Florida over the past century. With global change, minimum temperatures in the spring and winter seasons have become more variable within the temperate-subtropical zone that occurs across the peninsula and this variation is strongly associated with delayed flowering of both native and nonnative plant species. Nonnative species may be favored under the warming spring and winter conditions occurring in more northern latitudes, whereas they may not have differential responses under more stressful environmental conditions, such as the decreased winter and spring temperatures that have been occurring in Florida.
