From Texas A&M University (Kay Ledbetter):
A Texas A&M AgriLife-led team will work with the Colorado Livestock Association and a large team of Colorado stakeholders to refine and evaluate management practices to reduce agricultural ammonia emissions into Colorado’s Rocky Mountain National Park.
Agricultural operations along the northern Front Range of Colorado, including livestock operations, are believed to be a significant source of gaseous ammonia and other reactive nitrogen species in the atmosphere. Some of these may travel with air masses into Rocky Mountain National Park under so-called “upslope” conditions.
The Colorado Livestock Association, CLA, has been at the forefront of the nitrogen deposition issue for the last 15 years. Over that period of time, the association has acknowledged that animal agriculture is a source of ammonia and does contribute to ammonia deposition.
Last year, CLA conducted a survey of feedlot and dairy operations in Weld and Larimer counties to determine their use of best management practices recognized as effective in reducing ammonia emissions and the related barriers to adoption of those practices. Going forward, CLA is committed to communicating to the ag community and the public about the progress and results of the research.
Texas project outlined for Rocky Mountain work
Reducing ammonia emissions from livestock operations during upslope events will be the goal of the project led by Brent Auvermann, Ph.D., a Texas A&M AgriLife Research biological and agricultural engineer and Texas A&M AgriLife Research and Extension Center director, Amarillo.
“Upslope conditions bring rain and snow to the eastern side of the Continental Divide,” Auvermann said. Some of the reactive nitrogen in the atmosphere ends up dissolved in that precipitation and lands inside the national park, a process known as “wet deposition.”
Auvermann’s research team has operated a wet-deposition monitoring site on the rim of North Cita Canyon in Palo Duro Canyon State Park south of Amarillo since 2008.
“Our site is nearly identical to the monitoring sites in the (Rocky Mountain National) Park, where ecologists first discovered nitrogen enrichment changing the park’s vegetation and water chemistry,” he said.
Although not all of the atmospheric ammonia along the Front Range comes from agriculture, agriculture has an important role to play, he said.
“It doesn’t all come from Front Range sources either,” Auvermann said, noting that some of the nitrogen drifting into the national park comes from hundreds of miles away. “Still, we can make some good headway with the emitters nearby.”
Joining Auvermann on the research team are Ken Casey, Ph.D., AgriLife Research air quality engineer, Amarillo; and David Parker, Ph.D., research agricultural engineer and leader of the Livestock Nutrient Management Research Unit, USDA-Agricultural Research Service, Bushland.
The research team has a lot of experience with ammonia from cattle feed yards and dairies, having developed the emissions-reporting mechanism that was adopted by the U.S. Environmental Protection Agency from 2009 to 2019.
“EPA’s reporting instrument was based on research conducted right here in the Texas Panhandle,” Auvermann said. “Dr. Casey and Dr. Parker are widely known for their expertise in reactive nitrogen emissions.”
The new research project is funded by a Conservation Innovation Grant from the U.S. Department of Agriculture-Natural Resources Conservation Service, NRCS.
Colorado’s “glidepath” approach
Stakeholders, consultants, and state and federal agencies have been working on a strategy to reduce nitrogen enrichment in Rocky Mountain National Park for nearly 20 years, Auvermann said.
Their ultimate goal is to return the national park’s nitrogen budget to where it was many years ago using a strategy called the “glidepath.” The glidepath’s goal is to reduce the rate of nitrogen wet deposition in the park to 1.5 kilograms per hectare, or 1.34 pounds per acre, per year by 2032, with milestones along the way.
“That’s a little less than half of what’s landing in the park right now,” Auvermann said.
The Colorado team designed an early warning system, EWS, to notify crop and livestock producers of weather events that are expected to move the atmospheric nitrogen from Colorado’s eastern plains toward the Continental Divide.
“With a little advance notice, we think producers can make short-term changes that will reduce nitrogen loads in the park,” said Auvermann. “Now we need to figure out how to optimize those changes and make them work cost-effectively.”
Auvermann said while the effectiveness of those practices is proven scientifically, their project will deal with timing, amount, frequency, mode and operational variations of those practices. These details have not been worked out within the specific context of the EWS and components such as the forecast timing, duration and intensity of the upslope conditions.
Details determine management practices success
“We plan to help develop a decision tool for the voluntary implementation of two key practices by livestock producers in northeastern Colorado, both of which are intended to reduce ammonia emissions,” Auvermann said.
The two tools are:
Applying water to open-lot pen surfaces via sprinklers or water trucks. Variations include timing, depth and frequency of application, plus injection of acidifying or enzyme-inhibiting agents. Diluting irrigated wastewater with fresh water having a low concentration of dissolved nitrogen. Variations include the method of dilution – in-pipeline mixing, alternating effluent and freshwater applications – and injecting acidifying or other ammonia-suppressing agents.
Once the research is complete, the team will work with producers to optimize site-specific operational variables, and gain consensus for including those practices in cost-sharing programs, such as NRCS’ Environmental Quality Incentives Program, EQIP.
Some practices may be part of routine agricultural management and can be delayed or rescheduled due to the upslope conditions with little additional cost or management effort. Others, however, may be more labor-intensive or costly, in which case producers may incur significant costs in increased expenses and/or foregone revenue.
The team believes eligibility to receive EQIP cost-sharing funds to help defray the cost of implementation will increase the potential for voluntary adoption of those practices.
“Rocky Mountain National Park is the crown jewel of the national park system as far as I am concerned,” Auvermann said. “It’s a real privilege to be invited to help protect her.”