Carbon Key To Supporting Microbes Essential To Healthy, Productive Soil
Kris Brye, professor and soil expert from the University of Arkansas System Division of Agriculture, talks about the significance of soil textures with carbon sequestration. Here, with NERREC Director Tim Burcham, Brye shows highly compacted, or "cheesecake" soil. He was among the speakers July 20, 2022, during the Arkansas Discovery Farms field day at NE Rice Research and Extension Center in Poinsett County.
U of A System Division of Agriculture photo by Mary Hightower
MARY HIGHTOWER
HARRISBURG, ARKANSAS
Elements such as nitrogen and potassium can aid plant growth, but carbon is a key ingredient for healthy soils that can better support crops and help farmers manage a dwindling resource: water.
Kris Brye, professor of applied soil physics and pedology for the University of Arkansas System Division of Agriculture, talked about the importance of carbon during a July 20 field day held jointly by the Arkansas Discovery Farms program and Anheuser-Busch Foundation.
Anheuser-Busch agronomist Bill Jones said the company’s commitment to soil health practices is directly related to its 2025 corporate sustainability goals and “ambition to be net zero by 2040 and educating all stakeholders in the region is critical to succeeding at scale.”
The field day took the nearly 100 participants from the Northeast Rice Research and Extension Center in Poinsett County to the Anheuser-Busch plant in Jonesboro, and onto the Pratt farm in Light, Arkansas. At the Pratt farm, participants saw water monitoring activities by the Arkansas Discovery Farms and heard about the work the Discovery Farms program is doing in Arkansas to support sustainability and farm resource efficiency.
The field day also included in-field presentations on soil fertility, cover crops, nutrient management, rice agronomy and irrigation, as well as perspectives from local farmers on the value of land grant research and its utility in their work.
Carbon and microbes
“We need to have the soil function at some optimal level. We can supplement with fertilizer and control weeds, but you’ve got to keep the internal mechanics of the soil working well and that goes back to the microbes,” Brye told the crowd.
“Carbon is the one element that is going to keep the organisms going,” he said. “We don’t see them. It’s easy to forget about them. They’re the inherent biological component of the soil. Carbon is going to keep the soil thriving.”
Sequestration – or storing carbon in the soil – is neither a fast process nor are its results immediately obvious.
“With fertilizers, you see a response really quick. That’s not going to happen with carbon,” he said. “We want to build up carbon in the soil over time. You can’t do it overnight. You have to have some faith in the science of it. And there’s a lot of science behind it.”
Carbon and organic matter are critical to soil aggregation, a process where soil particles are held together in clumps by organic material.
Aggregation also means there are spaces in the soil for organisms to thrive or serve as a sponge-like medium for holding moisture.
In many places, the soil is compacted so densely, that water simply runs off. Brye demonstrated this with a plastic leftover storage container filled with what he called “cheesecake soil” so dense and non-aggregated, that it was hard to pry out of the container.
Brye said the ability to hold water is critical in areas such as the Delta, which rely on underground aquifers — aquifers that are dwindling quickly.
“Improving carbon content help soils to hold water and gives an opportunity for some rainfall and irrigation water that we are using to get returned to our aquifers, rather than run off in a ditch and evaporate into the atmosphere,” he said.
He lauded efforts “by big names to push this along.”
“This is a win-win situation for Arkansas farmers,” Brye said. “I believe Arkansas could be a national leader in sustainability efforts in rice.”
“Carbon is something we hadn’t really discussed at field days before,” said Mike Daniels, director of the Arkansas Discovery Farms program. “I hope this field day will get more farmers interested in this aspect of sustainability.”
Daniels said the division’s public-private partnership with Anheuser Busch, the largest buyer of rice in the United States, “is helping us research and educate farmers on different aspects of sustainability, or continuous improvement, that I believe will become increasingly important especially for future generation of farmers.”
Jones said he thought the event exceeded expectations.
“The presenters shared critical components of their research that will further help us at Anheuser-Busch develop on-farm programming relating to sustainability and carbon,” he said. “I have only received positive feedback, with a simple request of doing more of these going forward.”
Jones said he’s hoping there will be a similar event after harvest showcasing cover crops and related research data.
Progress at NERREC
The field day roadshow began at the Northeast Rice Research and Extension Center, with Director Tim Burcham giving an update on its progress. The station is in its second growing season and is building infrastructure, including a new well. He also talked about the station’s future with public meeting spaces and K-12 educational outreach about agriculture being led by Ashlyn Ussery, the field day coordinator.
NERREC is part of a network of centers and research stations operated by the Arkansas Agricultural Experiment Station, the research arm of the University of Arkansas System Division of Agriculture.
“We want to thank the Arkansas Rice Research and Promotion Board for their support of our station and continued support of rice research,”
Burcham said. “This field day was a great opportunity to showcase how we use funds from the board, as well as the private partnerships we have.”
Public-private partnerships
“Without their support, we would not be able to adequately address some of these future issues now,” Daniels said. “A lot of corporations that are part of the agricultural supply chain have sustainability plans and goals but Anheuser-Busch is investing in research and education efforts to help farmers voluntarily address sustainability.” ∆
MARY HIGHTOWER: University of Arkansas