In January 2005, Drs. Lawrence Tanner and David Smith and undergraduate students Amanda Allan and JennyLee Osborn traveled to the big island of Hawaii to study the effects of volcanogenic CO2 and SO2 on the frequency of leaf stomata of common swordfern. For nearly two weeks, the team collected swordfern at sites close to the volcanic plumes of Kilauea volcano, and at other more distant sites, and analyzed the samples at the University of Hawaii, Hilo. The results of the study indicate that stomatal index is lowest at sample sites where concentrations of both CO2 and SO2 or SO2 alone are much higher than background. Therefore, we propose that shifts in the stomatal index of fossil leaves may record transient atmospheric increases in both SO2 and CO2, such as may be caused by eruptions of flood basalts. A pdf of the resulting paper in Geophysical Research Letters is available here. The research was supported by a grant from the NSF Integrative Plant Biology program. Amanda has since graduated with a degree in biology, is currently employed, and is in the process of applying to graduate programs.
