Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2006
Publication Date: 11/12/2006
Citation: Lee, D., Zhang, Y., Clapp, C.E., Molina, J., Palazzo, J. 2006. Measurement of Carbon Dioxide Concentrations at Various Soil Depths Comparing Sensor and Gas Chromatography Data [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting. Nov. 12-16, 2006, Indianapolis, IN. 2006 CD ROM.
Technical Abstract: Measurement of field respiration is critical in studies of soil C and N dynamics and greenhouse gas emissions. CO2 and N2O concentrations in soil can vary rapidly and widely with factors such as tillage, fertilizer application, and rainfall, and are subject to both diurnal and seasonal variations. The objective of our paper is to compare CO2 and N2O concentration measurements at 7 soil depths (0, 10, 20, 30, 40, 50, 60 cm) in two treatments with and without crop roots over the growing season. Soil gas samples were extracted from various depths and analyzed by gas chromatography (GC) to determine CO2 and N2O concentrations in the soil air. Soil CO2 and N2O fluxes at the soil-air interface were measured using the chamber-based flux technique. The impacts of corn (Zea mays L.) root activity on the concentrations and fluxes of CO2 and N2O were documented in two years of corn growth at the University of Minnesota Rosemount Agricultural Experimental Station, Rosemount MN.