ARS | Publication request: Ammonia volatilization from soils amended with biochars of different pH

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 23, 2010
Publication Date: June 27, 2010
Citation: Harris, K., Gaskin, J., Schomberg, H.H., Das, K.C. 2010. Ammonia volatilization from soils amended with biochars of different pH [abstract]. Biochar Conference, June 27/30/2010, Ames, Iowa. CDROM.

Technical Abstract: A significant amount of nitrogen fertilizer applied to agricultural land is in the form of ammonium. Ammonium nitrogen can be lost through volatilization if applied under certain conditions, mainly to soils with a pH greater than 8. The pH of biochar varies from slightly acidic to highly alkaline depending on feedstock and production temperature. A considerable amount of nitrogen could be lost through volatilization if an ammonium containing fertilizer is applied to soil that has recently been amended with an alkaline biochar. We amended Norfolk soil (Fine-loamy, kaolinitic, thermic Typic Kandiudults) with eight biochars produced from four feedstocks and two temperatures each at a rate of 44 Mg ha-1 and measured NH3 volatilization over a 4 day period. The pH of the biochars used in the study ranged from 5.4 (switchgrass produced at 250° C) to 10.3 (poultry litter produced at 700° C). There was a strong correlation between soil pH after biochar application and ammonia volatilized.