Bringing the Vibe Down from Ten to Zero: Effects of Glacial Discharge on Northern Rockweed in the Gulf of Alaska

Abstract

Arctic glacial estuaries are unique and extremely dynamic maritime ecosystems, being simultaneously influenced by tidal action, oceanic currents, and terrestrial glacial meltwater. Since glacial melt and recession due to anthropogenic climate change are expected to accelerate, understanding how glacial discharge affects coastal ecosystems and their primary production is necessary to monitor these ecosystems as polar environments change drastically in the coming decades. This project aims to shed light on the relationship between glacial discharge and the nutritional content of one representative species of macroalgae in the Arctic, the northern rockweed (Fucus distichus). In order to investigate this relationship, I used nutritional and compositional data from F. distichus samples collected across six months at five Alaskan watershed sites to draw correlations with environmental data taken at each month and site. I conclude that, as an intertidal species that is well-adapted to colder waters, F. distichus is not expected to be significantly adversely affected by increasing glacial discharge and warming temperatures, though its quality as a food source may decline. Thus, the stability of F. distichus under disturbed conditions may not be indicative of the stability of the polar estuarine ecosystems to which they belong. While F. distichus will likely be relatively unaffected by climate change and its cascading effects on glaciers, it remains unclear how this suite of environmental changes will affect the ability of F. distichus to fulfill essential ecosystem functions in Alaskan littoral ecosystems more generally.