02107naa a2200265 a 450000100080000000500110000800800410001910000190006024501060007926000090018552012870019465000110148165000140149265000170150665000230152365000090154665000130155565300170156865300290158565300150161470000200162970000190164970000200166877301530168810154492015-06-08       2005    bl uuuu     u00u1 u    #d1 aMATALLO, M. B.  aSorption, degradation, and leaching of tebuthiuron and diuron in soil columns.h[electronic resource]  c2005  aA study in small outdoor lisimeters was carried out to determine the leaching of the herbicides tebuthiuron and diuron in different soil types, using undisturbed soil columns. Soil sorption and degradation for both herbicides were also studied in laboratory. The multi-layered AF (Attenuation Factor) model was evaluated for predicting the herbicides leaching in undisturbed soil columns. Tebuthiuron leached in larger amounts than diuron in both soils. Sorption was well represented by linear and Freundlich equations, however parameters from the linear equations were used in the AF model. In general, both herbicides presented very low sorption, with diuron presenting lower values of sorption coefficient than tebuthiuron in the two soils. Chromatographic data had indicated rapid late degradation of diuron and tebuthiuron in both soil types, in two different depths. Simple exponential equation was not able to represent degradation, thus a bi-exponential equation was used, and some model adjusting was needed. Average measured amounts of each herbicide were compared with amounts predicted by the multi-layered-soil AF model. The AF model was able to predict leaching amounts in the sandy soil, especially for diuron, however its performance was not good in the clayey soil.  adiuron  aHerbicida  aLixiviação  aModelo matemático  aSolo  aSorção  aDegradação  aDeteriorização do solo  aTebutiuron1 aSPADOTTO, C. A.1 aLUCHINI, L. C.1 aGOMES, M. A. F.  tJournal of Environmental Science and Health. Part B, Pesticides, Food Contaminants, and Agricultural Wastes, New Yorkgv. B40, n. 1, p. 39-43, 2005.