Laura Naslund, sitting in a canoe on a pond, smiles while taking emissions data.

A Day in the Life of a Pond: Measuring Small-Reservoir Emissions to Inform Infrastructure Decisions

By 7:45 a.m. on Tuesday, June 21, Laura Naslund had already spent over an hour in a canoe on a little pond on the east side of Athens, Georgia. Naslund, a graduate student in the Odum School of Ecology and a 2022 Spencer Grant recipient, was finishing up the first field sampling event of her new research project. She’d started work early on Monday morning, and was still paddling a canoe out to measure gas emissions all over the pond 24 hours later.

“The idea is to understand the times, places and pathways that are most important for emissions,” Naslund said over a quick breakfast, “and then apply that information to a later study at more sites which examines the drivers of the differences in emissions between sites.” 

There are 364 reservoirs in Athens-Clarke County, but only 23 of them are listed in the National Inventory of Dams, leaving hundreds of smaller reservoirs that receive far less attention from freshwater research and management alike.

Laura Naslund and volunteer assistant Ally Whiteis paddle a canoe across a small pond for field sampling.
Laura Naslund and volunteer assistant Ally Whiteis paddle a canoe across a small pond for sampling, around the 2-hour mark of the 24-hour field sampling.

Naslund believes these small reservoirs may have a much larger impact on inland water systems than we currently recognize. She hopes to expand our understanding of freshwater reservoir emissions by focusing research attention on the small ponds of Athens. The end goal of Naslund’s research is to help inform infrastructure decisions regarding which of these dams have the greatest environmental impact and which may be highest priority for removal.

“Particularly as we are about to have the largest infrastructure investment probably in my lifetime, I think now’s a good time to start thinking about how we can use ecological knowledge to inform where and what kind of infrastructure we have,” she explained. “And this project, I think, is a little bit unique among that body of work in that it’s focused on the end of an infrastructure life cycle.”

Naslund is particularly dedicated to accurate field testing: data collection for this research will involve sampling all over each test reservoir for over 24 hours at each event. These methods were designed to get the most accurate possible understanding of where, when and how gases are emitted throughout a day.

Laura Naslund paddles a canoe across a wollfia-covered pond.
Laura Naslund paddles a canoe across a wollfia-covered pond, around the 6-hour mark of her 24-hour field sampling.

“I think researchers have thought about spatial variation a lot, we’ve thought about seasonal variation a lot, but we’ve though less about the variation in emissions that happens over the course of a single day,” Naslund explained. By focusing on variation at a daily scale, Naslund hopes to collect emissions data that more accurately represents the natural history and spatial heterogeneity of a system.

It’s strenuous work to sample for 30 hours at a time, but Naslund doesn’t mind camping out. “The places that I’m working in are beautiful. So that always helps!”

She also acknowledged that she could not do this research alone. Her team of volunteer assistants included professors, undergraduates, and fellow graduate students, who came in shifts throughout the 30-hour sampling. “It’s been really great to collaborate with people, to show them new techniques, and to learn from them,” Naslund said.

Ally Whiteis, Odum undergraduate, paddles a canoe on a wolffia-covered pond.
Ally Whiteis, Odum undergraduate, paddling a field canoe.
Olivia Allen, Odum undergraduate, sitting behind Laura Naslund in a field canoe and recording data.
Olivia Allen, Odum undergraduate, recording data.

Naslund’s research is funded by the Network for Engineering With Nature, a collaboration between UGA and the US Army Corps of Engineers, along with a grant from the Odum School of Ecology and a 2022 Spencer Grant from the River Basin Center. The Spencer Grants are annual awards given to graduate students studying freshwater management and conservation. The grant is named for the late John Kyle Spencer, an Odum graduate student who was passionate about freshwater research. Research like Naslund’s is a reflection of this passion for freshwater science and cooperation among environmental researchers.

Photos and story by Olivia Allen

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.