Satellite Imagery Shows One-Third of Corn Belt Has Lost its Topsoil
University of Massachusetts Amherst research using satellite imagery shows that nearly 30 million acres of the Midwest Corn Belt has completely lost its A-horizon soil. The A-horizon is the upper portion of the soil—topsoil—that is rich in organic matter and contributes nutrient and water retention. The researchers say erosion of the A-horizon has already reduced corn and soybean yields by about 6%, leading to nearly $3 billion in annual economic losses for farmers across the Midwest. The A-horizon has primarily been lost on hilltops and ridgelines as a result of tillage erosion. Tillage erosion is not included in national assessments of soil loss, and researchers say this has led to significant underestimation of the true magnitude of farmland erosion. The researchers recommend incentives for no-till farming and regenerative agricultural practices to help restore soil productivity.