From ground to air to space: Tillage estimates get tech boost

According to national U.S. Department of Agriculture statistics, no-till and conservation tillage are increasing, with more than three-quarters of corn and soybean farmers opting for the practices to reduce soil erosion, maintain soil structure and save on fuel. However those estimates are based primarily on farmer self-reporting and are only compiled once every five years, potentially limiting accuracy.

In a new study, University of Illinois scientists demonstrate a way to accurately map tilled land in real time by integrating ground, airborne and satellite imagery.

“We’ve shown remote sensing can quantify regional-scale tillage information in a cost-effective manner. This field-level information can be used to support growers in their management practices, as well as to support agroecosystem modeling and provide tools to the USDA to verify their census data,” said the study’s lead author, Sheng Wang, a research assistant professor in University of Illinois’ department of natural resources and environmental sciences in the College of Agricultural, Consumer and Environmental Sciences. He is also a research scientist in the Agroecosystem Sustainability Center at University of Illinois.

Wang and the research team took photos of the ground at participating field sites throughout central Illinois, generating 6,719 GPS-tagged images. Then they arranged for an airplane equipped with high-powered hyperspectral sensors to fly over the region. The airborne system scanned 40,000 acres per hour and captured rich spectral signatures of the ground at a scale of about half a meter.