Hugh Ellerman received the 2026 Postdoctoral Excellence Award from the School of Natural Resources for his work with remote sensing in the ADAPT project.
The ADAPT project, short for Advancing Development of Assessments, Practices and Tools to Produce Climate Smart Beef in Grazing Systems, receives funding from the university through a $5-million Grand Challenges grant. Researchers on it have been studying the impact of grazing cattle on the environment since 2024. One of its main goals, and where Ellerman comes in, is assessing how greenhouse gases like carbon dioxide, nitrous oxide and methane ebb and flow in grazing systems.
“The idea behind that is that there's this general association between cattle and environment as, ‘Oh, cattle are bad for the environment, because of the methane they produce, and they eat the grass, which soaks up the carbon,’” Ellerman said. “And there's some research to suggest that maybe that's too broad of a statement. So, this grant evaluates what the relationship between cattle and greenhouse gas flux is and how it is shaped by the context of the grazing system.”
Scientists have identified greenhouse gases as causing climate change and established that carbon dioxide is exchanged between the atmosphere and the surface of the earth through photosynthesis. This exchange of energy is invisible to the human eye, but Ellerman and his team can use remote sensing to measure how efficiently plants use light to convert carbon dioxide into biomass.
With professors John Gamon and Ran Wang overseeing him, Ellerman has coordinated with another University of Nebraska–Lincoln postdoc and two students in assessing carbon dioxide exchange using three remote sensing technologies. On the ground, he, Biquan Zhao, Pedro Henrique Jota Fernandes and Ryan Barent have used a backpack with a sensor attached to look at the spectral response of vegetation. This tells how the vegetation is functioning, which they use as a proxy for greenhouse gas exchange.
When Ellerman uses the backpack system, Zhao flies a drone with a sensor in the same field site at the same time. The drone covers more ground than the backpack system, but the ground data from the backpack system can validate the drone data.
The third technology the team has been using, a sensor on an airplane, provides an even broader view of what is going on in the gas exchange. With it, they can assess an entire grazing system. Because absorption of light by molecules in the atmosphere can interfere with light signals, the team calibrates the aircraft data with the ground data. They and volunteers lay down tarps for the airplane to gather data in the same specific sections as the backpack system.
The broader ADAPT team has been using the team’s data and findings to look at the relationship between cattle and greenhouse gas flux in the environment and how that is shaped by the grazing system used. They are comparing grazing of cover crop and summer annual forages compared with perennial grass systems, rotational versus continuous grazing, supplementation effects to improve animal performance and patch burn grazing in rangelands to improve biodiversity of plant species.
Ellerman has coordinated the work of the remote sensing team, watching weather forecasts from 5 a.m. onward and organizing team members at the field sites on clear days to get good data. Wang noted Ellerman’s professionalism in carefully synchronizing weather windows, pilot availability, aircraft logistics and ground team readiness.
“This effort has often placed Hugh in a near 24-hour on-call role, as flight decisions have to be made swiftly and communicated efficiently across multiple operational partners,” Wang said. “His ability to coordinate these moving parts under tight and unpredictable constraints has been critical to the success of the campaign.”
Although part of the School of Natural Resources, Ellerman has also worked on the project with scientists from the Department of Biological Systems Engineering and the Department of Animal Science.
“He has become an essential anchor for the field team, ensuring seamless communication among faculty across multiple departments and maintaining alignment between diverse research objectives,” Wang said. “His ability to navigate interdisciplinary collaboration with varying priorities and methodological approaches, ranging from conducting field vegetation and spectroscopy data collection to managing crews for obtaining calibration data for ground-truthing airborne imagery, has been instrumental to the success of each field season.”
Besides the ADAPT work, Ellerman has taught the second semester of the Environmental Studies thesis course and has been creating maps of tree canopies for the university’s Center for Advanced Land Management Information Technologies. Primarily funded by ADAPT, which is year-by-year funding, he said he would like to shore up his funding and continue in similar work in Lincoln.
He has placed his Postdoctoral Excellence Award in his office and said he finds it especially gratifying since it comes at the word of people whose opinions about his work ethic he respects.
“It’s a bit validating,” he said. “And so, I feel like, ‘OK, there's some recognition for doing this work and putting the effort in, and I'll keep trying to be worthy of it.’”
