Date of Award
Master of Science in Integrative Biology (MSIB)
Dr. Mario Bretfeld
First Committee Member
Dr. Nicholas Green
Second Committee Member
Dr. Joel McNeal
Third Committee Member
Dr. Matthew Weand
A compound disturbance, composed of a prescribed fire and a periodical cicada emergence, occurred in northern Georgia in the summer of 2021. Independently these disturbances have substantial effects on the surrounding ecosystems. This study investigated the collective impact on soil composition and seed germination.
Through the soil analysis of cicada turrets, burned soil, and unburned soil, we hope to understand the composition of each soil type. Additionally, a 2 x 2 factorial study was performed with those same samples, providing insight into the impact on seed germination these disturbances have. The two factors were between burned and unburned soil as a base and whether turrets were present or not.
Turret samples had significantly higher Ca, P, Zn, and C% concentrations, and a higher pH than burned samples. Turrets also had significantly higher concentrations of all nutrients accounted for in the soil analysis than the unburned samples. Similarly, burned samples also contained higher concentrations of nutrients than unburned samples, except both samples, had the same pH. During the 2 x 2 factorial germination study, the treatment with the positive outcome on germination was the unburned soil, regardless of the turret's presence.
Our study shows that the compound disturbance of prescribed burning and soil bioturbation due to cicada emergence significantly impacted soil chemistry, increasing nutrient availability. We also found that these two events had either no effect or a negative effect on seeds germinating during our study.
Available for download on Thursday, May 11, 2023