Sorption and leaching of atrazine and MCPA in natural and peat-amended calcareous soils from Spain.
The sorption and leaching of atrazine and MCPA (0.02 M CaCl(2) aqueous solution at 25 degrees C) by a calcareous soil from Southeastern Spain, after organic carbon (OC) amendment with a commercial peat (from 0.18% to 4.61% OC), were studied in batch and soil column experiments. Adsorption capacity (K(f)) values, obtained by fitting the experimental data to the Freundlich equation, ranged from 0.24 mg kg(-)(1) for MCPA sorption on the original soil to 5.47 mg kg(-)(1) for atrazine sorption on the peat-amended soil containing 4.61% OC. The breakthrough curves obtained from the step-function soil column experiments indicated that the amount of herbicide adsorbed ranged from 17.5 mg kg(-)(1) for MCPA in the original soil to 331 mg kg(-)(1) for atrazine in the peat-amended soil containing 1.67% OC. The results obtained from the pulse experiments indicate that the mobility of MCPA is much greater than that corresponding to atrazine.
Socías-Viciana
M M
MM
Departamento de Química Inorgánica, Universidad de Almería, Almería 04120, Spain.
Fernández-Pérez
M
M
Villafranca-Sánchez
M
M
González-Pradas
E
E
Flores-Céspedes
F
F
D008456:2-Methyl-4-chlorophenoxyacetic Acid / Q000032:analysis*; D000327:Adsorption; D001280:Atrazine / Q000032:analysis*; D002122:Calcium Chloride; D006540:Herbicides / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D013030:Spain
D006540:Herbicides; D012987:Soil; D008456:2-Methyl-4-chlorophenoxyacetic Acid; D002122:Calcium Chloride; D001280:Atrazine