Title: Switchgrass and pecan biochar amendments to a sandy coastal soil Authors
|Ahmedna, Mohamed -|
Submitted to: Soil and Water Conservation Society Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 15, 2010
Publication Date: July 17, 2010
Citation: Busscher, W.J., Novak, J.M., Ahmedna, M. 2010. Switchgrass and pecan biochar amendments to a sandy coastal soil. 65th International Annual Meeting of the Soil and Water Conservation Society, July 17-21, 2010, Saint Louis, Missouri. Technical Abstract: Sandy soils of the wet, warm SE Coastal Plain have poor physical characteristics and low carbon contents. To improve soil properties, we added switchgrass (Panicum virgatum) and non-activated pecan (Carya illinoinensis) biochar. Switchgrass was ground to a fine powder and added to soil at rates of 0 or 20 ppm; soil was the Ap horizon of a Norfolk loamy sand, a thermic Typic Kandiudult. Biochar was developed by pyrolyzing ground pecan shells at 1300°F. Biochar had 88% C, 0.4% N (C:N ratio 220:1); 58% of its C resided in recalcitrant polymerized aromatic ring structures. Biochar was added to switchgrass treatments at rates of 0, 5, 10 or 20 ppm. Treatments were incubated in 1.7 lbs of soil in PVC columns for 70 days at 10% (w/w) water content. Both biochar and switchgrass amendments decreased soil penetration resistance and improved water retention. They also affected aggregation, infiltration, and water holding capacity; but results were mixed. Switchgrass and non-activated biochar can be used to improve soil physical characteristics; switchgrass amendments were not expected to last more than a year while the recalcitrant biochar should last much longer.