Date of Award
1-1-2025
Document Type
Thesis
Degree Name
M.S. in Biological Science
First Advisor
Colin Jackson
Second Advisor
Rebecca Prescott
Third Advisor
Peter Zee
School
University of Mississippi
Relational Format
dissertation/thesis
Abstract
Microbial extracellular enzymes play critical roles in the degradation of organic matter and mineralization of nutrients in marine systems, yet few studies have examined how enzyme activity varies over short-and long-term timescales in nearshore coastal environments. In this study, I assessed day-to-day, week-to-week, and month-to-month variation in the activity of three hydrolases (phosphatase, β-glucosidase, N-acetylglucosaminidase) in seawater and sand at five beaches along the Mississippi Gulf Coast. In addition, the activity of two oxidases (phenol oxidase, peroxidase) was assayed in sand, and environmental factors determined at each site. Seawater enzyme activity showed more variation over time than between beaches and showed the greatest variation on shorter-term scales. Hydrolase activity showed more spatial variation in sand than in seawater, and temporal variation in sand hydrolase activity was more correlated to seasonal differences than short term changes in environmental parameters. Oxidase activity in sand was highly variable with no consistent patterns over long- and short-term timescales. Salinity was a significant driver of seawater enzymatic activity at all timescales, although the effect of salinity on enzyme activity differed with the timescale considered. Sand enzyme activity was more influenced by temperature and moisture content. Ratios of enzyme activity in both sand and seawater suggested that microbial communities in beaches along the Mississippi coast are primarily limited by phosphorus and carbon. This study highlights the dynamic nature of microbial enzyme activity across different temporal scales and the role of environmental variability in shaping microbial function in nearshore Gulf of Mexico ecosystems.
Recommended Citation
Pavlovsky, Jacqueline, "Temporal Variation in Microbial Extracellular Enzyme Activity Along the Mississippi Gulf Coast" (2025). Electronic Theses and Dissertations. 3352.
https://egrove.olemiss.edu/etd/3352