Data for: A comparison of stomatal traits between contemporary and sub-fossil leaves of Melaleuca quinquenervia: do they reflect climate variation?
Stomatal traits have been shown to vary in predictable ways in response to environmental change in many species. As a consequence, stomatal traits in fossil leaves are sometimes used as proxies for past CO2 and climate. Here we investigate the influence of temperature, rainfall and CO2 on stomatal traits in Melaleuca quinquenervia. We use both modern and sub-fossil leaves to evaluate the effect of CO2, and modern leaves for climate variables. We found a significant negative relationship between stomatal size and density across both modern and sub-fossil leaves of M. quinquenervia. However, we were unable to find any relationship between stomatal traits and CO2 across a range from 260-380 ppm. Using the modern data set we were unable to find any robust relationships between stomatal traits and either evaporation or temperature. Apogeotropic roots account for the lack of stomatal anatomy correlation to evaporation in a region that experiences inundation. We conclude that stomatal size is a highly plastic trait in this species and changes do not necessarily reflect functional changes in the leaves.