Many geoscientists get into the field through a love of the outdoors and a chance to escape the city. But for Danielle Zaleski, cities are where some of the most interesting -- and important -- questions in geosciences originate. That includes her research on the buildup of microplastics in the sediment of Lake Austin and Lady Bird Lake, both just a couple of miles from The University of Texas at Austin campus.
"When I saw an advertisement about researching microplastics in Austin's waterways, that was immediately eye-catching," said Zaleski, who graduated in May with a Bachelor of Science in geology from the UT Jackson School of Geosciences. "It had the urban aspect that I liked, along with the geology and the environmental work."
Working with Cornel Olariu, a research associate professor in the Department of Earth and Planetary Sciences, and Marcy Davis, an engineering scientist for the Institute for Geophysics, Zaleski has spent the past two-and-a-half years as a student scientist analyzing how microplastics -- ranging in size from 45 micrometers to 1 millimeter -- have been accumulating in the lakes as the city grows.
Microplastics are everywhere. Scientists have found them on Earth's highest peaks and in its deepest ocean trenches. So, when Zaleski started filtering microplastics in core samples from the bottom of Lake Austin and Lady Bird Lake, their abundance came as no surprise.
She found them in every section of core pulled from the lake bottoms, with most being "road wear particles" -- bits of asphalt binding and synthetic materials from tires.
Her research is helping inform a City of Austin report on the scope of microplastic pollution and what can potentially be done about it. At the same time, it has helped Zaleski grow as a geoscientist and prove herself as a valuable scientist in the lab.
"Give her a small idea, and then suddenly, the next day, it's double," Olariu said. "It's her style to improve and innovate."
For example, Olariu credits Zaleski with coming up with the method the lab uses to count microplastic particles in lake core samples under the microscope, which can reach into the thousands.
"I told her a few basic things about [the software we use to count the microplastics], but she discovered the method we use herself, and she gave us the way to do it," he said.