Manhattan — When farmers and ranchers burn grassland each spring, it’s difficult to track just how much grass is burned and the impact of that smoke. That’s why Rhett Mohler, a Kansas State University doctoral student in geography, Wakeeney, is developing a new technique to accurately track the burning of tallgrass prairie in Kansas and Oklahoma. Mohler’s project also could enable the modeling of smoke plumes, which could help predict the effects of burning’s byproducts downwind.
To map the burned areas Mohler will use data and images from satellite systems, including the Thematic Mapper and NASA’s Moderate Resolution Imaging Spectroradiometer sensors, and combine that with information he gathers using sensors on the ground.
By combining these techniques, he’ll develop a set of criteria that can accurately detect what kind of ground cover is in an area, whether it’s been burned and how recently. By integrating historical images, Mohler will build a set of maps dating back to 2000.
“What we’ll have is a retrospective for each burn that is large enough to detect, information on when it happened, where and how much grass actually got burned,” said Douglas Goodin, K-State professor of geography and Mohler’s adviser.
The study will contribute to a broader body of knowledge by examining and mapping the burning of tallgrass, which is a less-studied cover type.
Each spring, farmers and ranchers in the Midwest burn their pastures in an effort to clear dead plant material and encourage new growth. But the resulting smoke sometimes raises questions about the trade-offs between air quality and land management.
Some have made the argument that burning in rural areas is responsible for increased air pollution in more urban areas.
“In order to estimate how the effects are going to play out in Wichita, Kansas City, Omaha, Neb., maybe Tulsa, Okla., and even farther, we need to know how much area is burned every year, or at least be able to make an informed estimate,” Mohler said. “Mapping the burns is the best way to try and figure that out.”
After Mohler’s mapping technique is refined, Goodin said they’ll look at spikes in air quality data to determine whether spring burns add to pollution in cities.
“This project will look at air quality in certain urban airsheds and see if there is a correlation between burn events and increases in certain air quality indicators,” Goodin said.
The technique could provide scientific data critical to building relationships between stakeholders, according to Goodin.
“This research will ensure that partnerships are built between researchers, extension personnel and local ranchers,” he said.
Mohler’s research is supported by a National Science Foundation Doctoral Dissertation Research Improvement grant.