Tennessee Aquarium and UGA’s River Basin Center to Host Pioneering Workshop Addressing Freshwater Microplastic Pollution

Writer: Casey Phillips

Chattanooga, Tenn. (Sept. 10, 2020) – It is the inevitable destiny of all water that falls on land to eventually return to the sea. And like an enthusiastic tourist, it can’t help but pick up souvenirs along the way, whether it’s dirt, fertilizers or — as many scientists now suspect — plastic.

In recent years, the world slowly has awoken to the, ironically, enormous impact microscopic plastic has on marine life. Every year, an average of 8.8 million tons (about 17.6 billion pounds) of plastic fragments or manufactured plastic objects measuring smaller than five millimeters across enter the ocean. There, they’re consumed by microscopic organisms and eventually work their way up the food chain to humans.

Although the bulk of plastic waste originates inland, microplastic is largely seen as a coastal issue thanks to images of plastic debris piled up on beaches or found inside marine animals. Little is known about how this plague of plastic affects the rivers, lakes and streams through which it passes on its way to the sea.

On Sept. 14, the Tennessee Aquarium Conservation Institute hopes to make inroads to answering that question as host to a virtual workshop on freshwater microplastic research. The workshop was organized in partnership with the River Basin Center at the University of Georgia. 

Among other topics, participants in the one-day summit will focus on developing standards to ensure current and future researchers can reliably compare and build on each other’s findings.

“In a new field of research where so many different methods are being used, it is extremely important that studies are designed and conducted so we can compare and replicate results from different labs,” says Dr. Anna George, the Aquarium’s vice president of conservation science and education.

“Not only will these studies improve our understanding of how plastic pollution reaches the ocean, they will also provide insight into an emerging threat to maintaining clean water for us all.”

The workshop initially was scheduled to take place in April at the Conservation Institute’s headquarters on the banks of the Tennessee River. However, the ongoing health crisis necessitated a different approach, and it now will be held via Zoom video conference.  

Dr. Krista Capps, an assistant professor with the Odum School of Ecology and Savannah River Ecology Lab, helped organize the workshop of 50 participants. Her research into how microplastic is affected by water treatment facilities has been hampered by a lack of agreed-upon research standards.

The issues caused by this absence of structure spurred the idea for the upcoming workshop, Dr. Capps says.

“There are currently no accepted standard methodologies to collect and identify microplastic pollution, as the field is developing so quickly,” she says. “Many researchers I contacted were also frustrated by this situation. The workshop is an outgrowth of my search for expert advice and a quest to develop standard quality assurance and quality control protocols for sampling and analysis.”

The workshop participants represent a variety of institutions, including the University of Georgia, Sewanee: The University of the South, Auburn University, Mississippi State University, the University of Alabama and Vanderbilt University as well as Riverkeeper organizations, SeaGrant consortiums and government agencies.

“Plastic pollution is a problem that affects everyone,” Dr. Capps says. “The greater diversity of stakeholders and academic disciplines involved in working on this problem, the more holistic our approach to understanding plastic pollution will be.”

The workshop will feature presentations by several experts, including:

·         Dr. Rae McNeish, an assistant professor of biology at California State University, Bakersfield

·         Dr. Jeremy Conkle, an associate professor of physical and environmental science at Texas A&M University, Corpus Christi

·         Dr. Andreas Fath, a professor of physical chemistry and analytics at Germany’s Furtwangen University

Dr. Fath made headlines in 2017 with a record-setting marathon swim of the entire 652-length of the Tennessee River. During this 34-day undertaking, he and his team took daily measurements of various water quality indicators, including the presence of microplastics. With data from locations along the entire course of the river, this “swim for science” represented one of the first comprehensive studies of how microplastic moves through freshwater systems.

Analysis of the project’s findings found microplastic levels in the Tennessee River that were 80 times higher than Dr. Fath detected during a similar study of Germany’s Rhine River in 2014. These results were a clear sign that microplastics have a greater, if largely uninvestigated, potential to impact freshwater sources than previously assumed, Dr. George says.

“Some freshwater-focused scientists, myself included, thought plastic in freshwater was moving out to the ocean so quickly that it probably wasn’t having a major impact on freshwater habitats or animals,” she says. “Dr. Fath’s work demonstrated that there was enough microplastic pollution in freshwater habitats that we needed to learn more about its impact in our streams and rivers.”

For more information about the Tennessee Aquarium Conservation Institute, visit tnaqua.org/conserve

To learn more about the River Basin Center at the University of Georgia, visit ecology.uga.edu.

Details about Dr. Andreas Fath’s TenneSwim project are at en.rheines-wasser.eu.

Third Wednesday Symposium, Fall 2020

This year’s line up of Third Wednesday speakers is here! Due to COVID-19 all seminars will take place via Zoom. Scroll down for information about how to access them.

Due to Zoom security considerations, we will not be publishing the link until two hours prior to each Third Wednesday Seminar.

The zoom link will be sent out to the River Basin Center mailing list. If you want to make sure you receive it, or if you aren’t sure whether you’re already on the mailing list, please add your email using the link below.

Congratulations to our 2020 John Spencer Research Grant recipients!

The River Basin Center John Spencer Research Grants support graduate students affiliated with the RBC with small grants of up to $2,000. This program was launched in 2016 with a generous donation from Kathleen Amos, and is named in honor of her son, John Spencer, a former master’s student at the River Basin Center and Odum School of Ecology.

Donations to this fund are currently being accepted through the River Center Fund. Please include RBC Spencer Grants in the Special Instructions on page two of the form.

Meet this year’s recipients

Carolyn Cummins

I am a PhD student in Dr. Amy Rosemond’s lab, and my research is focused on the effects of temperature on stream ecosystems. Specifically, I am interested in how stream insects respond to temperature and how these responses may scale up to affect ecosystem processes like leaf litter breakdown. I am originally from Durango, Colorado and attended Colorado State University. I have always been interested in the natural world, and this was nurtured further after I got involved with research and had the opportunity to do field work late in my undergraduate career. I switched my focus from pre-vet to Ecology, and the rest is history! In my spare time, I enjoy cycling, hiking, rock climbing, and cooking!


Ranjit Bawa

My research includes two general and overlapping areas of interest. First is how modeling non-point source (NPS) pollution influences water quality, especially as it pertains to the role of human interaction. Second, I am interested in advancing economic applications as it relates to agent behavior in the context of decision-making under uncertainty and ultimately, policy design. My most recent work attempts to value changes in water yields by surveying Georgia landowners whose forests serve as watersheds for the provision of critical ecological services (i.e. increased water yields). I am originally from the Boston area and worked in finance before returning to school for graduate studies in Statistics and Agricultural Economics some years later. Most recently, I was based in Minneapolis prior to starting my research program at the University of Georgia. In my spare time, I enjoy exploring new hiking trails around northeast Georgia and basketball.


Derrick Platero

My project is a detailed characterization of soil physical properties, which are critical inputs for modeling landscape-scale water table fluctuations. Spatial predictions of these properties with depth at the field-scale are often related to microtopography, which can be represented with detailed topographic indices. Proximal sensing techniques like electrical resistivity tomography (ERT) and electromagnetic Induction (EMI) are more useful in identifying subsurface features associated with changes in ground conductivity. EMI has been used to quantify a variety of soil properties including texture, moisture, and pH. The objective of this research was to create detailed maps of sand, silt, and clay by depth for a 50-acre crop field in a Georgia Piedmont floodplain using a combination of depth-averaged specific conductance from EMI and topographic indices derived from lidar. We will develop spatial predictions of soil texture for each increment using regression-kriging and random forest models, and will compare them to available data in soil surveys. Models will be validated using k-fold cross validation. The resulting maps will be used to direct a subsequent sampling effort focused on soil hydraulic properties and water table modeling. Soil texture maps are an essential part of the soil assessment framework which can support advances in sensor technology and computer modeling. I am from the Navajo Nation located in New Mexico. I completed my undergraduate degree with a Bachelors in Agriculture in Soil Science with a minor in geology at New Mexico State University. I am currently working on my M.S. in Soil Science at UGA and plan to do my PhD after completion. I have a passion for Geo sciences–specifically soil science, hydrology, geology, and agriculture.


Laura Kojima

I am a first year Master’s student in the CESD program in Odum and my research is focused on alligator ecotoxicology and movement behavior. I am currently looking at the frequency with which alligators on the Department of Energy’s Savannah River Site move on and off the site to public hunting grounds and whether this puts hunters/consumers at risk of contaminant exposure. This is done through GPS/telemetry and biological sample collection. The funding from RBC will also contribute to looking at the potential for alligators to act as biological vectors for contaminants through a captive study, in which we collect feces, analyze it for contaminant off-loading, and compare contaminant levels to that of other biological samples such as blood and tail muscle. I have a research background in herpetology, and am originally from California, where I worked with western pond turtles during my undergraduate degree at UC Davis. Right after graduation, I worked with USGS on their giant gartersnake project for a season then took a few months off before moving for grad school. 

UPPER OCONEE SCIENCE AND POLICY SUMMIT

In partnership with the Upper Oconee Watershed Network, the UGA River Basin Center, UGA Office of Sustainability, ACC Stormwater,  and ACC Water Conservation will host the third biennial Upper Oconee Watershed Policy Summit.  “Exploring the Intersection of Science and Policy in the Upper Oconee Watershed” will occur on Friday September 25, 2020. This will be a virtual event!

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The Role of Freshwater Crabs in Neotropical Streams

Freshwater crabs play an important role in the breakdown of nutrients from natural materials that fall into streams, but few studies have looked into exactly how their relationships with other detritivores and the leaf litter itself impacts ecosystems.  

River Basin Center graduate student Carol Yang shed light on these relationships in neotropical streams in two recently published papers.

In a paper published in Freshwater BiologyYang did an in-stream experiment in Monteverde, Costa Rica to examine the leaf litter in enclosures that contained crabs as compared to enclosures without crabs. One dynamic that Yang and colleagues hoped to learn more about was the relationship between crabs and other detritivores—which contribute to leaf breakdown, but that crabs frequently prey upon. 

Throughout the study, Yang and collaborators regularly sampled the leaf litter. They found that enclosures with crabs had faster rates of breakdown than those without, indicating that their manipulation and consumption of leaves had a larger impact than their consumption of other detritivores and shredders. 

In a follow up study published in Nauplius, Yang used a laboratory setting to gain a more in-depth understanding of the crab behaviors that most impacted leaf litter. The crabs were collected from Monteverde, Costa Rica, and transported to aquariums along with unfiltered stream water and leaves from a common subcanopy tree. 

Yang and colleagues found that the leaf mass was significantly higher in tanks with crabs than those without. They also used visual observations and recordings to watch as the crabs used their claws to grasp and shred the leaves, which aided in ingestion. At the end of the experiment, they observed that leaves in tanks with crabs were broken up into multiple pieces, whereas leaves in tanks without them remained whole.    

These studies suggest that crabs play an important role in helping to process the detritus that accumulates in neotropical streams, especially given their abundance in tropical streams. 

RBC Graduate Student Shishir Rao Featured in Nature inFocus

River Basin Center graduate student Shishir Rao’s research was recently feature in Nature inFocus, as part of the Save Every Drop Series. Rao studies how hydroelectric power (including small dams, which are installed in higher altitude rivers in the Western Ghats impact river biodiversity.

Rao has found the installation of these small hydroelectric projects disrupt migratory species, the diversion of water (which causes other portions of the river to dry up), the fluctuation of water levels, which threaten sensitive species, the accumulation of silt and sediment, which are later released and can suffocate fish. They may also contribute to human-elephant conflicts in neighboring communities.

To read more, check out the article here: https://www.natureinfocus.in/save-every-drop/a-voice-for-our-rivers