Sorption and transport of atrazine for stable manure-amended agricultural soil from Kahramanmaraş, Turkey

Abstract

ABSTRACT This study investigated how adding stable manure affected the transport of atrazine within agricultural soils from Kahramanmaraş, Turkey. Based on the batch and miscible-displacement experiments, it was found that atrazine sorption was nonlinear, following a Freundlich isotherm, and was rate-limited and reversible for both the non-amended and amended soil. The addition of manure resulted in higher retardation of atrazine, with R values of 10.1 to 19.1, compared to values of 3.2 to 4.3 for the non-amended soil. The KF values for stable-manure amended soil calculated from batch experiment was three times higher than non-amended soil. The transportation of atrazine shows non-ideal behavior, characterized by significant elution tailing at low concentrations due to the organic carbon content of the soil. This effect was more prominent in soil with a 10% stable-manure amendment. By incorporating non-linear sorption, a two-site transport modeling approach provides a reasonably accurate representation of the atrazine breakthrough curves. The distinct sorption-desorption characteristics of atrazine have significant implications for risk assessment of atrazine-contaminated soil and should be considered in the regulation, management, and remediation of such contaminated sites.