Two Deltas, One Crop: What a Vietnam Partnership Means for Arkansas Rice

U of A engineer Benjamin Runkle is studying rice sustainability on two continents at once, and the payoff could reach your favorite rice dish. In August, he traveled to Vietnam's Mekong Delta to begin testing whether a low-cost, Arkansas-proven strategy for cutting rice farming's emissions holds up in one of the world's largest rice-growing regions.

"Every single person on earth knows what rice is and has a favorite dish, whether it's sushi or grandma's beans and rice," Runkle said. That universal connection is what makes this partnership worth building, benefiting farmers and consumers alike.

The payoff cuts both ways. As global buyers demand proof that rice is grown with lower emissions, Arkansas, the nation's top rice-producing state, stands to gain the most from having reliable ways to measure and prove sustainable practices. And for everyday consumers, that research could mean more environmentally friendly rice on store shelves, without a higher price tag.

Building on a Decade of Arkansas Research

Runkle, a professor in the U of A's Department of Biological and Agricultural Engineering, and his team have spent years studying the environmental footprint of rice production in the Arkansas Delta, measuring water use, methane emissions and the tradeoffs between sustainability practices and farm yield or income. "We have developed expertise in Arkansas quantifying sustainability outcomes of rice production practices," Runkle said.

That expertise led to the Southeast Asia Innovation Alliance for a Global Model of Future Agri-food Systems (SIGMA), a four-institution alliance linking the U of A, the University of Illinois, the National University of Singapore and Can Tho University in Vietnam. The University of Illinois' existing ties to Singapore opened the door to Southeast Asia, and five private funders backed the project.

Benjamin Runkle, left, works with Huynh Van Thao, a Can Tho University researcher to review data during fieldwork in Vietnam. (Photo by Huynh Cong Khanh)

After two earlier visits to lay the groundwork, Runkle made his third trip to Vietnam this summer to begin field measurements. He and his technician, Marc Gomez Prats, worked alongside researchers at Can Tho University in the heart of the Mekong Delta. The region produces roughly half of Vietnam's rice, making it central to the country's food security, economy and rural communities, much like Arkansas.

Testing an Arkansas Strategy Abroad

At the center of the fieldwork is methane, a naturally occurring gas released by soil microbes in flooded, oxygen-poor rice paddies. In Arkansas, Runkle's team has been assessing different irrigation strategies to see how much they can cut emissions without hurting yield.

"We found that farmers in Arkansas can reduce their methane emissions by 60% to 80% without impacting yield and without increasing costs," Runkle said. The Vietnam trial will show whether that low-cost, low-risk result holds up in a very different growing system.

Vietnam has committed internationally to cut agricultural emissions, but Runkle said funders and policymakers need reliable, ground-level data before they'll trust those reductions are real.

"Everybody who is paying for a methane emission reduction wants high certainty that that's actually being done, and to get high certainty, you need more on the ground data," he said.

At the core, the science is similar to here in Arkansas.

"Some of the underlying biology, chemistry and physics are the same, and the underlying techniques that we use to measure those are also the same," Runkle said. His team uses closed chambers placed briefly over the soil to trap the gases microbes release in Vietnam and Arkansas.

The farming systems differ, though. Vietnam's tropical climate allows three rice crops a year instead of Arkansas' one, meaning three times the data in the same span of time and potentially more cumulative methane, which makes emissions cuts even more consequential there.

Marc Gomez Prats and Vo My Hung, a technician from Can Tho University, check conditions along a rice field in Vietnam's Mekong Delta. (Photo by Benjamin Runkle)

Getting reliable data starts with measuring the same way. Gomez Prats said the main goal of this trip was training staff and researchers at Can Tho University on the methods and equipment used in Arkansas, including water-level sensors and gas-sampling protocols, and reviewing their existing procedures. Consistent methods are essential, Gomez Prats said, so data from both teams can be directly compared.

The work also crosses language and culture. Neither Runkle nor his team speaks Vietnamese, so they relied on their Can Tho colleagues to translate not just the words, but the ways of working and the culture. Runkle said it was a good reminder that people are more alike than different.

"I think a lot of times we think that people are so different, but actually we have so much in common," said Runkle of the cultural exchange from the project.

That exchange of knowledge is something Gomez Prats is excited to be a part of too. "It's a unique opportunity to exchange knowledge and contribute to the future of sustainable rice production," he said.

What It Means for Arkansas

Runkle sees opportunities for Arkansas farmers and consumers to benefit from the knowledge gained through this partnership.

For Arkansas rice farmers exploring higher-value, sustainability-branded products, Vietnam's experience navigating a much larger rice-consuming market could offer a preview of paths forward. And for everyday consumers, research aimed at making sustainable practices verifiable could eventually mean more environmentally sound rice, grown at home or abroad, reaching store shelves without a higher price tag.

There's also a direct payoff for the state's bottom line. Arkansas grows about 45% of all rice produced in the United States, more than any other state, so its farmers have the most to gain as buyers, exporters and international trade agreements increasingly ask for proof that rice was grown with lower emissions. The measurement methods Runkle's team is refining in Vietnam are the same tools that could let Arkansas farmers document and get credit for practices many have already adopted.

The work also sits squarely on one of the university's stated priorities. Food Systems & Nutrition is one of five priority research growth areas in 150 Forward: Reaching Higher, the campus strategic plan, which seeks to strengthen Arkansas' agricultural economy. Runkle's rice research, an engineering project rooted in the Arkansas Delta and now reaching into the Mekong, is what echoes that priority. 

The Vietnam work is just beginning. Runkle described it as the start of a one- to two-year data-collection effort he hopes to build into something larger, with future plans to bring Vietnamese students or scientists to Arkansas, or send more of his own team abroad.

From this research, Runkle hopes people will think more about the work behind their food. "We take it for granted," he said of the technology, countless people and decisions it takes to get food to the plate in a safe and sustainable way.

Farmers in Arkansas and Vietnam alike are practical and eager to learn about improvements they can make to this process, Runkle said, but they are also "rightfully very conservative about making changes" when a mistake could cost them income. That is why the project aims to make sure farmers actually benefit from growing rice more sustainably.

"Our hope is that the measurements and the modeling that we're doing can help facilitate payments to farmers for doing the right thing, for using sustainability practices, and reduce the cost of it, so that it opens up more opportunities for farmers," he said.

About the College of Engineering: The University of Arkansas College of Engineering is the state's largest engineering school, enrolling 4,701 students, including 3,608 undergraduate students and 1,093 graduate students. The college has more than 150 faculty and researchers and nearly 200 staff. The college ranked 65th among public institutions in the 2026 U.S. News & World Report Best Graduate Engineering Schools rankings and had $66.6 million in new research awards in fiscal year 2026. Its strategic plan, Vision 2035, will dramatically increase the state's engineering graduates by 2035, an outcome that will add $3.9 billion annually to Arkansas' economy.