Predicting Pesticide Transport in Mulch-Amended Soils
A Two-Compartment Model
Liwang Maa and
H. M. Selimb,*
a USDA-ARS, Great Plains Systems Research Unit, 2150 Centre Avenue, Building D, Fort Collins, CO 80526
b Dep. of Agronomy and Environmental Management, Louisiana State Univ., Baton Rouge, LA 70803
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Fig. 1. A schematic diagram of the second-order two-site model.
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Fig. 2. Atrazine concentration in solution at various adsorption-desorption times in batch Exp. I. Solid lines are ‘overall’ fitted results and dash lines are predicted from averaged parameters of individually fitted adsorption-desorption curves for each initial concentration (see Table 2).
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Fig. 3. Total atrazine adsorbed by sugarcane residue vs. distribution coefficient (Kd) for estimating maximum adsorption capacity (Smax).
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Fig. 4. Atrazine concentration in solution at various adsorption-desorption times in batch Exp. II.
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Fig. 5. Atrazine concentration in solution at various adsorption-desorption times in batch Exp. III.
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Fig. 6. Measured and simulated atrazine breakthrough curves (BTCs) from the sand + mulch column. Arrows indicate pore volumes when flow interruptions occurred.
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Fig. 7. Measured and simulated atrazine breakthrough curves (BTCs) from the Sharkey + mulch column. Arrows indicate pore volumes when flow interruptions occurred.
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Copyright © 2005 by the Soil Science Society of America.
