Sorption‐Desorption Behavior of Atrazine in Soils Irrigated with Reclaimed Wastewater

Abstract

increase the amount and change the properties of the natural SOM. For instance, irrigation with wastewater A time-dependent sorption-desorption study of atrazine (2-chlorofor a period of 25 yr increased the organic C level in a 4-ethylamino-6-isopropylamine-s-triazine) was performed to reveal its behavior in wastewater-and freshwater-irrigated soils. Atrazine soil by 50% (Friedel et al., 2000). In addition, Gonzalezsorption affinity to the freshwater-irrigated soils was significantly Vila et al. (1995) reported that irrigation with olive mill higher than to their wastewater-irrigated counterparts. The calculated effluents increased and altered the composition of the C-normalized partition coefficient (K OC) values for the freshwatersoil lipid fraction. In another report, changes in the irrigated soils were 70.7 and 34.2 L kg Ϫ1 organic C and the values for chemical properties of fulvic acid were obtained after the wastewater-irrigated soils were 52.6 and 29.9, respectively, for irrigation with wastewater (Boyd and Sommers, 1990). the two tested soils. These differences did not result from atrazine Application of sewage sludge has also been reported to interactions with dissolved organic matter (DOM) in the wastewaterincrease the amount of aromatic compounds in the irrigated soils. All desorption isotherms exhibited hysteresis. Lower SOM, due to enhanced microbial activity and degradadesorption was exhibited for the 14-d sorption-desorption experition of readily degradable DOM and SOM fractions ments, even though the sorption-affinity parameters were similar for the 2-and 14-d sorption periods. Higher desorption hysteresis was (Kalbitz et al., 2003). observed for the longer sorbate-sorbent contact time for both soils, Hydrophobic organic compounds (HOCs) tend to with desorption decreasing for decreased atrazine loading. The similar sorb to soils mainly via interactions with SOM. Many atrazine-sorption parameters obtained for the two sorption periods reports have shown a positive correlation between the and the increasingly difficult desorption with increasing contact time organic C content and the sorption potential of HOCs suggest that the sorption process occurs in two stages. First, sorption (Means et al., 1980; Garbarini and Lion, 1986; Kleineioccurs to readily available sites; at a later stage, the sorbed molecules dam et al., 1999). Therefore, SOM is considered to siginteract with the soil organic matter (SOM) or the SOM-mineral nificantly affect the fate of HOCs in the environment. complexes such that their desorption ability is significantly hindered. The ability of SOM to sorb and, more importantly, to The higher sorption potential and the lower desorption ability of the desorb HOCs in the soil profile significantly affects the freshwater-irrigated soils suggest that the SOM which develops in the wastewater-irrigated soils delays or hinders atrazine interaction with transport of these pollutants toward groundwater. In sites that are naturally present in these soils. addition to the amount of SOM, the sorp...

Effect of soil type and organic manure on adsorption–desorption of flubendiamide

“…This was used as an index of hysteresis. Scientifically, lower H 1 values indicate increase in difficulty of sorbed analyte to desorb from the matrix (Cox et al 1997;Drori et al 2005;Ismail and Kalithasan 2004). The combined effect of increased clay and organic carbon content is responsible for the increased irreversibility of flubendiamide sorption.…”

Environmental Fate of the Herbicide MCPA in Two Soils as Affected by the Presence of Wheat Ash

“…However, desorption of MCPA from pure wheat ash was lower at the concentration of 5.7 mg L −1 than that at the concentration of 56.6 mg.L −1 . This could be explained by the limited number of sites available for high-energy binding, which are occupied first at lower solute concentrations, whereas at high solute concentrations, more molecules are retained by low-energy sites and therefore can more easily desorb (Celis and Koskinen 1999;Drori et al 2005). It was expected that desorption of MCPA from ash-amended soils corresponding to the lower initial concentration would be similar to that from pure wheat ash, but such behavior was not observed (Table 2).…”

Fate of carbamazepine, its metabolites, and lamotrigine in soils irrigated with reclaimed wastewater: Sorption, leaching and plant uptake

“…Sorption affinities of compounds to each soil followed the order: lamotrigine > carbamazepine > EP-CBZ > DiOH-CBZ. The higher sorption affinity of lamotrigine can be explained by the presence of triazine ring and amino groups, resulting in the enhanced ability of the molecules to form hydrogen bonds with functional groups on soil surfaces, particularly with polar soil organic matter (Drori et al, 2005;Welhouse and Bleam, 1993). Borgman and Chefetz (2013) demonstrated the importance of organic matter content for lamotrigine sorption to soil: increased retardation in soil columns was observed when biosolids were added to sandy soil.…”