Poster

         Ecophysiology

Responses of Leaf Stomata to 50 Years of CO2 Increase Using Herbarium Specimens

Presenting Author
Jazlyn Salazar
Description
Herbarium specimens provide a glimpse into various past characteristics of plants, which includes the ways that they interacted and responded to the environment. Plant gas exchange is a key process shaping global hydrological and carbon cycles and is often able to be characterized by plant water use efficiency. Plants are able to balance CO2 intake with water loss by regulating the stomatal pore aperture and guard cell signaling is regulated by both environmental factors and plant hormones from plant fossil records, it is suggested that plant adaptation to changing atmospheric CO2 has a correlated evolution in stomatal density and size. Together, stomatal density and size contribute to determining the maximum leaf conductance of CO2, and in this study we used herbarium specimens to track stomata over time. A collection of over 1500 plant specimens housed in the E.L. Reed Herbarium at Texas Tech is from a survey of Guadalupe National Park in the 1970s. From this collection to modern specimens of the same species, we identify how plants responded to over 50 years of CO2 addition. Our results can use a look into the past in the floristic biological diversity to predict how plant communities will respond to future climate changes.