title: Rate of loss of simazine, terbuthylazine, isoproturon, and methabenzthiazuron during soil solarization.
abstract: This paper reports the use of solar heating by polyethylene mulching for decontamination of a silty clay-loam soil polluted with herbicides. Soil solarization, a natural and hydrothermal method commonly used for disinfesting soils, was tested during the summer season on a Hipercalcic Calcisol located in Murcia (southeast Spain) for dissipation of s-triazine (simazine and terbuthylazine) and phenylurea (isoproturon and methabenzthiazuron) herbicides using low-density (LD) and high-density (HD) polyethylene (PE) film as a cover. A well-established influence of the film was observed on the dissipation of all herbicides from the soil, although the density (0.92-0.95 g/cm(3)) of the film used (LDPE and HDPE) was not significant in terms of the rate of loss. In all cases, a quick depletion during the first 2 weeks was observed, mainly for terbuthylazine. The first-order model satisfactorily explained the dissipation process, but the Hoerl and biexponential equations were more appropriate, mainly for simazine, isoproturon, and methabenzthiazuron. In all cases, herbicides disappeared at faster rates in solarized soils (DT(50) = 4-29 days) than in nonmulched soils (DT(50) = 11-35 days), especially for terbuthylazine and isoproturon.
authors.affiliation: Departamento de Química Agrícola, Geología y Edafología, Facultad de Química, Universidad de Murcia, 30100 Murcia, Spain. snavarro@um.es
authors.forename: Simón
authors.initials: S
authors.lastname: Navarro
authors.forename: Salvador
authors.initials: S
authors.lastname: Bermejo
authors.forename: Nuria
authors.initials: N
authors.lastname: Vela
authors.forename: Joaquín
authors.initials: J
authors.lastname: Hernández
mesh_terms: D052160:Benzothiazoles / Q000032:analysis; D006540:Herbicides / Q000032:analysis* / Q000737:chemistry; D007700:Kinetics; D008782:Methylurea Compounds / Q000032:analysis; D010671:Phenylurea Compounds / Q000032:analysis; D012839:Simazine / Q000032:analysis; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D013472:Sunlight; D014227:Triazines / Q000032:analysis
chemical_list: D052160:Benzothiazoles; D006540:Herbicides; D008782:Methylurea Compounds; D010671:Phenylurea Compounds; D012987:Soil; D012989:Soil Pollutants; D014227:Triazines; C028904:isoproturon; C011912:methabenzthiazuron; C037565:terbutylazine; D012839:Simazine