Soil health benefits of perennial biofuel crops on claypan soils

Authors: SUTTON, DYLAN - University Of Missouri; Veum, Kristen; DAVIS, MORGAN - University Of Missouri; LORD, SAMUEL - University Of Missouri; Ransom, Curtis; Sudduth, Kenneth

Submitted to: Soil Security
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/2025
Publication Date: 5/22/2025
Citation: Sutton, D., Veum, K.S., Davis, M.P., Lord, S., Ransom, C.J., Sudduth, K.A. 2025. Soil health benefits of perennial biofuel crops on claypan soils. Soil Security. 19. Article 100193. https://doi.org/10.1016/j.soisec.2025.100193.
DOI: https://doi.org/10.1016/j.soisec.2025.100193

Interpretive Summary: Fast growing, perennial biofuel crops, such as switchgrass and miscanthus, can be used as feedstock for alternative fuels. They are especially appealing on marginal soils where grain crop production may not be economically viable. The Central Claypan Area of Missouri is challenged by degraded soils with high erosion and runoff potential. Perennial biofuel crops have the potential to improve soil characteristics and maintain productivity in this region. This study compared the soil health status of switchgrass, miscanthus, and a corn-soybean rotation after 14 years on soils with varying depth to claypan (e.g., varying topsoil depth). The results of this study found that perennial biofuel crops can improve multiple soil health indicators, especially in soils with shallow (< 15 cm) topsoil. These results highlight the soil health benefits of biofuel crops and provide information to landowners and conservation planners seeking to optimize production on marginal claypan soils.

Technical Abstract: Claypan depth is one of the most significant drivers in varying soil productivity across different agricultural cropping systems in claypan soils, and the benefits of perennial biofuel cropping systems have been a topic of interest for decades. In general, perennial systems consistently exhibit higher soil health status than annual row crop systems due to greater above and belowground organic inputs and year-round soil cover. In this study, we evaluated the effect of long-term (14 yr) cropping systems (i.e., corn-soybean rotation, switchgrass, and miscanthus) and claypan depth (i.e., < 15 cm, 15-30 cm, and 30+ cm) on soil health indicators at the Soil Productivity Assessment for Renewable Energy and Conservation site located in the Central Claypan Area of Missouri, USA. The cropping systems were sampled at 0-15 cm and a suite of 12 soil health indicators were measured. Analysis of variance models were used to examine the effect of cropping system and claypan depth on soil health indicators. Results showed that switchgrass and miscanthus systems had consistently higher soil health status than the corn-soybean system, with switchgrass demonstrating larger response ratios than miscanthus. Further, differences were enhanced in soils with shallow (< 15 cm) depth to claypan, including soil organic carbon, total nitrogen, acid phosphatase activity, arylsulfatase activity, ß-glucosaminidase activity, permanganate oxidizable carbon, soil respiration, total protein, potentially mineralizable nitrogen, and aggregate stability. These results demonstrate the potential soil health benefits of long-term, perennial biofuel cropping systems on shallow claypan soils. These results demonstrate the potential soil health benefits of long-term, perennial biofuel cropping systems on shallow claypan soils.