ARS | Publication request: Restoration of eroded landscapes to reduce variability in soil properties affecting productivity

Submitted to: Meeting Abstract
Publication Type: Abstract
Publication Acceptance Date: July 30, 2008
Publication Date: N/A

Technical Abstract: In hilly landscapes, tillage and water erosion combine to induce large variability in soil productivity at the field scale. Approaches to manage this variability have been proposed, including restoring the landscape by physically moving soil from areas of net deposition to areas of net soil loss. We evaluated the variability in soil properties and crop yield in an eroded landscape that has been cultivated for the past 100 years and in portions of the same landscape subject to restoration. In highly-eroded positions (summit, shoulder and upper backslope), the surface soil is comprised of exposed subsoil high in inorganic carbon. Deep accumulation (>40 cm) of high-organic-matter soil was observed in the footslope and toeslope. Surface soil organic carbon, Olsen phosphorus, nitrate-N and total nitrogen concentrations in the toeslope were more than twice that in the summit, shoulder and upper backslope positions prior to restoration. After moving accumulated topsoil from the footslope and toeslope to the eroded upper landscape positions, surface soil organic carbon, phosphorus and total nitrogen concentrations in upper slope positions were similar to those in the toeslope. In the first two years following restoration, crop yields were uniform from the summit through the footslope in the restored plots. In unrestored plots, minimum yields (in the upper backslope) were only 40% of yields in the footslope. These results indicate that soil movement from areas of net deposition to areas of topsoil depletion may reduce the spatial variability in soil properties that affect productivity in eroded landscapes.