Submitted to: International Soil Tillage Research Organization Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 15, 2009
Publication Date: June 15, 2009
Citation: Runion, G.B., Prior, S.A., Rogers Jr, H.H., Torbert III, H.A. 2009. Effects of Tillage Practice and Elevated Atmospheric CO2 Level on Soil CO2 Efflux. In: Sustainable Agriculture, Proceedings of 18th International Conference of the International Soil Tillage Research Organization, June 15-19, 2009, Izmir, Turkey. 2009 CDROM. Technical Abstract: Elevated atmospheric CO2 can affect both the quantity and quality of plant tissues, which will impact the cycling and storage of carbon (C) within plant/soil systems and the rate of CO2 release back to the atmosphere; research is needed to more accurately quantify the effects of CO2 on soil respiration in order to predict the potential of terrestrial ecosystems to sequester C. We investigated the effects of atmospheric CO2 concentration on soil respiration within two cropping systems (conventional and conservation). The study used a split-plot design replicated three times with two cropping systems as main plots and two CO2 levels (ambient and twice ambient) as subplots using open top field chambers on a Decatur silt loam (clayey, kaolinitic, thermic Rhodic Paleudults). The conventional system consisted of a grain sorghum [Sorghum bicolor (L.) Moench.] and soybean [Glycine max (L.) Merr.] rotation using conventional tillage practices and winter fallow; the conservation system used the same primary row crops, but included three cover crops in the rotation [crimson clover (Trifolium incarnatum L.), sun hemp (Crotalaria juncea L.), and wheat (Triticum aestivum L.)] and used no-tillage practices. Effects of cropping system and atmospheric CO2 concentration on soil respiration (measured using a novel, continuous soil CO2 efflux monitoring system), and its impact on carbon sequestration will be discussed.