December 11, 2020
By Brock Parker
Dr. Carla Atkinson, an associate professor in UA’s Department of Biological Sciences, recently received the award, which is one of the most prestigious recognitions of top-performing young scientists. Additionally, her water quality research, along with two other UA colleagues, has earned a 4-year $1.7 million NSF EPSCoR Track 2 grant to study intermittent streams as part of a national project.
More than half of North America’s species of freshwater mussels live in Alabama’s rivers – 180 to be exact – and they are also one of the most imperiled faunal groups in the world. Atkinson’s NSF CAREER award will allow her to continue her efforts.
“The goal of this project is to further examine how they influence ecosystem functions,” said Atkinson. “We’re going to be looking at a plethora of these species traits, including how much they bury and move, their shell morphology and how much they excrete as far as nutrients like nitrogen and phosphorous.”
Freshwater mussels are filter feeders, which means they clean water by filtering particles through their water column and into their gill chambers. At the same time, they’re excreting nutrients back into the ecosystem. Many species bury themselves together in sediment substrates, creating a tight-knit community.
“We can think of these areas where they occur in these dense aggregations as hotspots of productivity where they’re cleaning up the water, but then also fertilizing the algae and the base of the food web,” she said. “That can fuel the rest of the food web, making these river systems more productive and also harboring a higher abundance of other organisms, such as aquatic insects and fish.”
Mussels are imperiled because many of these river ecosystems are affected by human interference. They are sensitive to pollutants, and if there is a lot of runoff from agriculture or development, for example, they could also be buried and have their siphons covered up.
Atkinson said one of the most traumatic changes to their environments was the damming of rivers. Many mussels are adapted to live in free-flowing water, and dams create lake habitats upstream. Mussels attach themselves to fish in order to move around, and that movement is limited in reservoirs.
There are also problems downstream of dams. Water temperature can vary depending on where it eventually flows through the dam. If it’s released from the bottom, cold water comes rushing through onto the mussels.
“Some species might use temperature cues to know when to reproduce, and if it never reaches that temperature, then they’re not going to reproduce,” said Atkinson.
Some dams are used for hydropower, which can also affect the mussels.
“When they’re generating a lot of electricity, they’ll open the gates, causing a lot of high flow to go through. Then when they close the gates, that stops,” she said. “You can imagine that it could be quite stressful for an aquatic organism which has been adapted to the conditions in that river for millions of years.”
Atkinson said some agencies are now modifying water management and flow through dams to be more beneficial to native aquatic species and will hopefully increase those populations.
Higher biodiversity of mussels can be found in rivers unencumbered by dams, such as the Sipsey and Cahaba rivers. That’s where Atkinson spends quite a bit of time with her students, who will also benefit from her NSF CAREER award.
“Not only is it about research, but it’s also about education,” she said. “This is training the next generation of scientists by bringing everything from undergrads into the lab and into the field, to grad students and a postdoc. That way we kind of have this trajectory of different experiences and get to share our research experiences and questions with one another.”
Atkinson is also part of a team of UA biologists that will work on a national research project to address water quality at the critical connection between streams that flow continuously and those with intermittent flow. She, along with Dr. Jon Benstead, professor of biological sciences, and Dr. Nathaniel Jones, assistant professor of biological sciences, will be part of the project led by the University of Kansas as part of the NSF Established Program to Stimulate Competitive Research, or EPSCoR, grant. UA will receive $1.7 million as its share of the overall $6 million grant between 18 professors and eight institutions across the U.S.
These smaller streams are ubiquitous across the county, and they control the quantity and quality of water delivered downstream to perennially flowing rivers. They make up more than half of the stream miles globally, so it’s necessary to fill in the knowledge gaps of how they impact stream health.
“As a group, we collectively feel like they’re very important to study from a water quality perspective,” Atkinson said. “We want to understand how these streams that flow only a small portion of the year, up to maybe even 70 or 80 percent of the year, are impacting downstream water quality.”
The effort is the Aquatic Intermittency effects on Microbiomes in Streams, or AIMS, project. The researchers plan to install new sensors and field sites, train a dozen graduate students and numerous undergraduates in team-science approaches, train 36 new instructors in teaching data science methods and boost workforce development and education.
The AIMS project will address the first obstacle by creating a network of instrumented sites designed to generate “Big Data” to quantify flow intermittency, stream microbiomes and water quality. AIMS will confront the second obstacle by using its network to provide training in collaborative science and interdisciplinary methods to study intermittent streams and by providing workforce training in environmental data tools through a new “On Ramps to Data Science” program, which will focus on data generated by microbiome sequencing, environmental sensors and Geographic Information Systems.
“We’re trying to enhance data-science tools across this whole program in which we’ll be doing training through The Carpentries foundation,” Atkinson said. “That way we can bring some data intensive courses to University of Alabama students, but also work with Alabama A&M in Huntsville to bring some different instructional tools to them.”
The work will also inform sometimes thorny policy and legal debates.
“The streams that are known as intermittently flowing streams are no longer protected under the Clean Water Act, so essentially they have no protections afforded to them,” said Atkinson.
Research results could help resolve difficulties defining ecological connections between perennial and intermittent streams that lie at the heart of an ongoing policy debate over legal protection of isolated water bodies, as recently demonstrated by the late 2019 repeal of the 2015 Waters of the U.S. Rule. The researchers said the infrastructure installation planned under the AIMS project is designed to confront these difficulties head-on.
Information from articles at the UA News Center was used in this feature.