Submitted to: American Society of Agronomy Meetings
Publication Type: Abstract only
Publication Acceptance Date: 1/20/2001
Publication Date: 1/20/2001
Citation: Torbert, H.A., Prior, S.A., Rogers, H.H. Elevated atomospheric CO2 in agro-ecosystems: Effects on nutrient leaching. Agronomy Abstracts. 2000. p. 331. Interpretive Summary:
Technical Abstract: Increasing atmospheric CO2 concentration has led to concerns about global changes to the environment. One area of global change that has not been fully addressed is the potential changes to nutrient leaching. This study was conducted to examine the effects of soybean (Glycine max (L.) Merr.) and grain sorghum (Sorghum bicolor (L.) Moench.) CO2- enriched agro-ecosystem on nutrient leaching in a Blanton loamy sand (loamy siliceous, thermic Grossarenic Paleudults). The study was a split-plot design replicated three times with two plant species as the main plots and two CO2 levels (375 and 705 ppm CO2) as subplots using open top field chambers. Fertlizer application was made with 15N- depleted NH4NO3 to act as a fertilizer tracer. Soil solution samples were collected weekly at 90-cm depth for a five-year period and monitored for NO3-N, NH4-N, salinity, and organic C concentration. Elevated CO2 increased total biomass in both crops and increased plant N uptake. Elevated CO2 decreased NO3-N concentration below the root zone in both crops. Elevated CO2 impacted other nutrient leaching.