Movement, adsorption and mineralization of atrazine in two soils with and without switchgrass (Panicum virgatum) roots

A study was conducted to determine the influence of switchgrass roots on th e mobility, adsorption-desorption and mineralization of atrazine in Cullen clay loam and Emporia loamy sand soils. Bromide and atrazine distribution p rofiles in the leachates indicated greater preferential movement in columns with roots than in columns without roots. Larger concentrations of atrazin e were detected at lower depths of Emporia soil with switchgrass roots than without. Adsorption of atrazine was greater in Cullen than in Emporia soil and conformed to Freundlich isotherms. In both Cullen and Emporia soils, a dsorption and desorption were not different between soil with or without sw itchgrass roots. After 84 days of incubation, less than 6% of the applied a trazine was mineralized in the Cullen soil and 2% in Emporia soil. Minerali zation was greater in the Cullen soil than in the Emporia soil at 42, 56, 7 0 and 84 days of sampling. The presence of switchgrass roots did not affect the mineralization of atrazine in Emporia soil. The presence of switchgras s roots caused preferential movement of atrazine, but did not affect its ad sorption and mineralization in either soil type.