Estimating the leaching of fenitrothion and thiobencarb in agricultural soils using laboratory lysimeters
Mohamed R. Fouad, Ahmed F. El-Aswad, Maher I. Aly
Abstract
The total amount of iodide applied was recovered from all lysimeters in symmetrical curves. Fenitrothion-BTCs included two peaks, while thiobencarb-BTCs included one peak in the two tested soil types. The cumulative of fenitrothion (75.3%) and thiobencarb (75.8%) from sandy clay loam soil-lysimeter were significantly higher compared with that of fenitrothion (21.1%) and thiobencarb (60.9%) from clay soil-lysimeter. Also, in clay soil-lysimeters, thiobencarb was more leaching (60.9%) compared to fenitrothion (21.1%). Nevertheless, in the sandy-lysimeter, the cummulative amounts of both compounds were almost the same (75.5%). Thiobencarb was more leaching and more rapidly in clay soil than fenitrothion. Whereas the leaching of the two compounds was almost the same in sandy clay loam soil. However, the leaching of thiobencarb was the fastest one. Fenitrothion required more water (about twice) for leaching from the two tested soil types compared to thiobencarb. Leaching statistics are needed to manage environmental protection and keep pesticides from reaching groundwater, as well as to anticipate and comprehend the behavior of pesticides in various soil types.