Effect of liquid sewage sludge addition on atrazine sorption and desorption by soil

摘要: Liquid sewage sludge (LSS) addition to soil incorporates both insoluble suspended organic material and large amounts of dissolved matter (LSSDOM) which can influence the sorption-desorption behaviour pesticides by constituents. Batch sorption isotherm techniques were used determine relative effect from a LSS on desorption herbicide atrazine soil. Atrazine isotherms obtained soil, LSS, LSS-amended LSSDOM-pretreated described Freundlich equation. The overall (insoluble matter) was increase sorption, due high capacity added matter. In contrast, LSSDOM, mainly constituted low molecular weight molecules, decreased No evidences for stable interactions in solution between LSSDOM found, thus suggesting processes taking place at soil/solution interface, such as competition sites surface, are main responsible observed decrease LSSDOM. Desorption also enhanced but this highly reduced when had been pretreated with soluble or alone. these cases, surface have already taken before experiment effects during less evident. results work suggest that applied soils may enhance risk groundwater contamination promoting especially surfaces free