Poster Session & Social
4:40 PM - 6:30 PM Wed
POSTER PRESENTER #21
TITLE: Effect of trophic state and water depth on the growth of European frog-bit
ABSTRACT: Hydrocharis morsus-ranae (European frog-bit; EFB) is a free floating aquatic plant native to Europe and Asia. It was introduced to Ottawa, Canada in 1930 and has since spread throughout upper and eastern Michigan. It inhabits coastal wetlands where its invasion is often facilitated by invasive cattail. EFB spreads via the growth of stolons, horizontal asexual sprouts that form genetically identical clones of the original plant that can eventually form a dense mat. Mat expansion and subsequent decomposition reduces dissolved oxygen, which negatively impacts macroinvertebrate and fish communities. Determining the ideal habitat for EFB is key to preventing its spread, however there is a lack of data describing the influence of environmental factors on the growth of EFB. In this study, I conducted a fully factorial experiment to analyze the effects of nutrient concentration, and water depth on EFB growth. I collected EFB individuals from two Northern Michigan coastal wetlands, then randomly assigned the samples to 4 treatments of 10 replicates each crossing high and low nutrient concentration with high and low water depth. I also ran an environmental chamber study in which I studied the impact of the four different nutrient concentrations on EFB growth. Results showed that individuals placed in the low nutrient and low water depth treatments experienced the greatest growth. The results of the environmental chamber study were in line with those of the mesocosm experiment, showing increased growth at the lowest nutrient concentrations. I will use the data collected to inform a study further investigating EFB’s invasive range.
BIO: Spencer Dzyacky is a second year student at Loyola University Chicago. He is studying conservation and restoration ecology and pairs his schoolwork with participation in a research group, "Team Typha", that conducts large scale habitat restoration on cattail invaded Great Lakes coastal wetlands.