POSTER PRESENTER: http://tinyurl.com/2024WSC-Dzyacky TITLE: Looking into the effects of freighter wakes on wetland distribution within the St. Marys River ABSTRACT: The St. Marys River is the connecting channel between Lake Superior and Lake Huron; it is the only passage large shipping vessels (freighters) can use for travel. The freighters create large amounts of wave energy that results in shoreline erosion. The US Army Corps of Engineers (Corps) approved construction of a third lock for the St. Marys river that may result in increased frequency of freighter traffic. Wave action creates erosion, potentially resulting in wetland loss along the river's shores. In this project, I plan to model the effects of freighters on the presence of Schoenoplectus acutus and Typha spp. I’m using these plants as a proxy for wetlands because their wave tolerance is the maximum wave energy a coastal wetland can receive. In the summer of 2023, I collected water depth, location, and density data of both emergent plants across a transect divided into equally spaced subplots. Sampling occurred in 5 areas with paired sites that are exposed and unexposed to the freighter channel. Using spatial analysis software (ArcGIS pro), I applied a fetch (distance across a body of water) value as well as distance from the channel to each plot surveyed as well as created a weighted distance from channel based on land cover classes created by Michigan Tech Research Institute. I found that the weighted distance (cost distance) from the channel to the shore was the greatest predictor of emergent plant presence. Based on my data, the slope of the wetland is also most affected by the exposure to the channel, which contradicts the traditional belief that fetch has the greatest affect on wetland slope/distribution. In the future, I plan to create a model that measures the effects of increasing freighter traffic. I also hope to use high-frequency water depth monitors to measure the amount of wave energy generated by the freighters. BIO: Spencer Dzyacky is an undergraduate researcher at Loyola University Chicago. He is a carbon undergraduate research fellow and this is the second time he has been to this conference.