Biology (B.S.B.)

Document Type and Release Option

Thesis (restricted to Georgia Southern)

Faculty Mentor

Dr. Craig Aumack


One of the most crucial, though understudied, polar ecosystems affected by increasing air and water temperatures is landfast sea-ice. As sea water freezes salt ions are pushed out during crystallization and form dense hypersaline waterways known as brine channels. These brine channels are teeming with life, though the community structure and how it is influenced by abiotic changes are largely unknown. I wanted to look at how changes in irradiance affected community dynamics and predicted that more irradiance would result in greater abundances of photosynthetic microalgae. To conduct this research, a snow gradient with gradually increasing snow depths were maintained overlying landfast Arctic sea ice. After six weeks, cores were taken from beneath the gradient, melted, and the microalgal community identified and numerated to determine the altered irradiance effects on interstitial community dynamics. Results indicated that abiotic changes in light availability and ice insulation, both heavily dependent on overlying snow, significantly affect both interstitial community abundance and diversity. Climate warming in the Arctic is likely to cause losses in overlying snow, dramatically changing the sea ice community. How these changes in the sea ice community affect the underlying marine ecosystem is still unknown.

Thesis Summary

This study is about changes in sea ice algal communities based upon the effect of varying irradiance.