The U-M Water Center has awarded six grants, totaling more than $500,000 to increase freshwater research and teaching at the university. EEB recipients include Melissa Duhaime, assistant research scientist, and Timothy James, assistant professor.
The Water Center initiative will engage diverse faculty and researchers to address critical freshwater issues. A primary goal is to support projects that address key challenges at the interface of the natural, social, physical, and health sciences.
Duhaime and her collaborators are working on “Microplastics in the Great Lakes: towards establishing a long-term multidisciplinary research platform to assess the impact of microplastics on Laurentian Great Lakes ecosystem health.” Her project was awarded over $270,000, the Water Center’s only large grant awarded this cycle.
Recently, plastic has been documented in the Great Lakes at the highest concentrations seen anywhere on the planet, according to the project summary. Yet, too little is known about the fate of this plastic and its role in ecosystem dynamics to predict the inevitable impacts on one fifth of the world’s fresh water. Therefore, this project takes a cross-disciplinary and multiscale approach to define the ecological and environmental health risks of plastics in the Great Lakes.
Regionally, the project team will quantify and identify plastics in Lakes Erie, southeast Huron and Superior, improve circulation models to better predict transport of plastics through the Laurentian system, contribute to remediation plans, and disseminate knowledge through school curriculum. On the micro-scale, the team will quantify and qualify the degree of plasticbound organic pollutants and explore plastic-dwelling microbial community dynamics and function, a virtually unexplored topic, including the exploration of microbes that may help break down the pollutants that readily adsorb to plastic, or even the plastic itself.
The diverse expertise assembled for this project leverages U-M towards becoming an epicenter for microplastic research in the Great Lakes, and in fact the world, with many of the anticipated findings relevant to better understanding implications of plastics in all aquatic environments.
While most people think of floating water bottles and plastic bags when they think of plastics polluting our waters, some 85 percent of the Great Lakes plastic is in the form of small, nearly invisible microplastics. Of particular concern are persistent bioaccumulative toxins (PBTs), which have high affinities for and accumulate at high concentrations on plastic particles, increasing their toxicity when ingested, explained Duhaime. Additionally, plastic additives affect reproduction, impair development and induce genetic aberrations in all molluscs, crustaceans, amphibians, and fish studied, even at low, environmentally relevant levels. These PBTs are likely to be bioaccumulating in plastic-ingesting organisms with unknown consequences on the food chain and human health. Duhaime’s research project will provide the first comprehensive survey of Great Lakes plastic-microbe biofilm community composition and function.
James project is “Identifying the environmental controls of algal pathogen epidemics and their influence on harmful algal blooms in Lake Erie,” working with EEB Ph.D. student John Marino and Gary Fahnenstiel, research scientist, Water Center. The project was funded at $50,000, the maximum award for the center’s leveraging grants.
James project summary explains that harmful algal blooms caused by rapid growth of certain algal species, are a major economic and ecological problem in freshwater and marine ecosystems. In Lake Erie, these blooms have increased in recent years, driven primarily by climatic conditions and nutrient inputs. Much attention has been given to better understand these blooms but little effort has focused on why natural enemies (i.e., parasites and predators) do not restrict these rapid explosions in the populations of harmful algal species. The role of parasites in limiting algal blooms in the Great Lakes is particularly understudied, despite evidence that parasites, especially fungi, can play an important role in limiting algal population growth.
This project seeks to improve understanding of the influence of fungal parasites on harmful algal blooms in two ways. First, a field survey will be conducted using state-of-the-art molecular techniques to measure the diversity of fungal parasites of harmful algae and identify which species are most common and likely important. Second, a laboratory experiment with be conducted to examine how nutrients and temperature influence epidemics of parasites in algae, which should provide insight into how recent environmental changes in Lake Erie influenced these parasites.
The findings of this project will be useful in establishing the conditions under which parasites, a potentially important control on algal blooms, thrive and impact their host species. In addition, this work will greatly advance the research capacity at U-M to broadly examine the diversity and impact of algal pathogens in the Great Lakes. The project creates a freshwater collaboration on campus and enables a new, freshwater application of a faculty member’s expertise and that of a postdoctoral fellow.
Duhaime was interviewed recently by Michigan Public Radio’s The Environment Report about her research. Listen here.