For decades, scientists have studied the link between conservation agriculture practices and environmental benefits in the United States Corn Belt, including improved water quality and climate change mitigation. Most of those publications sit behind paywalls and cannot be accessed by the general public. Now, anyone can access this body of research with a new online tool.
AgEvidence is a database of nearly 300 peer-reviewed research papers from 1980 with more than 15,000 data points. Visualization analytics enable users to easily navigate and interpret the data. AgEvidence also provides curated expert insights that are gleaned from the data on important topics. A map of all of the studies draws attention to geographies with little data where more studies could be conducted. (Watch this tutorial video on how the navigate the AgEvidence dashboard.)
The AgEvidence database was compiled as part of the Managing Soil Carbon working group of the Science for Nature and People Partnership, which is a partnership of The Nature Conservancy (TNC), Wildlife Conservation Society, and the National Center for Ecological Analysis and Synthesis at the University of California, Santa Barbara. Lesley W. Atwood, Ph.D., the postdoctoral scholar with the working group, developed the database.
A prototype of the visualization dashboard was built during a three-day “sprint,” a process bringing together a small group of cross-functional experts, led by TNC’s Agility Lab. The Agility Lab is a team of expert facilitators who act nimbly in the face of uncertainty, helping teams to execute impactful workshops in a cost-effective, rapid manner.
Interview with Stephen Wood, Ph.D.
Learn how to access and explore the research data and curated insights in AgEvidence.
Listen to the PodcastUsing AgEvidence to Advance Conservation by Understanding Benefits and Trade-offs
“Because there’s so much science on this topic, different people and organizations can have different literature they refer to, which can lead to different conclusions about the evidence,” said Stephen Wood, Ph.D., senior scientist, Agriculture and Food Systems at TNC. “With AgEvidence, we set out to build a comprehensive and easy-to-access data platform allowing for greater alignment among groups about the state of the evidence.”
The research compiled in AgEvidence focuses on the impacts of cover crops, tillage, pest management and nutrient management practices on corn and/or soybean crops in the Midwest. The scientists developing the database assessed nearly 2,500 articles, from which they selected and collected data from nearly 300 that were deemed relevant. The AgEvidence site provides more detail about the methods.
For users looking for quick answers to important questions, AgEvidence offers curated insights that use the data to answer a multitude of questions about the relationship between conservation agriculture practices and impacts to the environment. For instance, “Which practices best improve water quality?” or “What are the impacts of common cover crop use?” Users seeking to go beyond the curated insights can create their own, in-depth custom views of the data.

Some key insights from AgEvidence are:
- Evidence shows that no-till leads to increased carbon storage in surface soils and lower nitrous oxide emissions.
- Both reduced tillage and cover crops benefit water quality.
- Targeted fertilizer management and reduced tillage benefit crop yields.
- The long-term impacts of cover crops are difficult to assess because most of the studies in the database are from less than five years.
For those interested in going beyond the statistical capabilities of the tool, raw data can be exported for formal scientific analyses. For instance, Emma Fuller, director of sustainability science at Granular, wanted to explore in more depth the relationship between tillage and corn yields.
“Reviewing the data table in AgEvidence of the interaction between tillage and corn yields, it seemed like some of the biggest differences in treatment effect had baseline yields that looked on the lower end of what we observe in the field,” Fuller said. “Pulling out the data and grouping into yield bins—indeed it does seem like there’s an interaction between baseline yields and tillage effect.” This highlights an opportunity for further research.

AgEvidence is made possible by support from the Science for Nature and People Partnership, Craig and Susan McCaw Foundation, Nestlé Purina, Walmart.org, the Foundation for Food and Agriculture Research and Amazon Web Services.