DYNAMIC OF HERBICIDES IN SOIL AND SOIL MODIFIED WITH CLAY AND /OR HUMUS

Herbicides are one of the most widely used agrochemical classes around world. They help farmers to protect their crops against weeds. However, they can move through soil profile polluting water resources and adversely affect human health. Groundwater is an important source for production drinking in many places world presence pesticide residues groundwater a serious threat health consumers water. In this work, behavior two herbicides Atrazine Trifluralin were study agricultural soil: Alhue modified whit clay (Kaolinite) organic matter (Humus). The original samples characterized by physicochemical properties: pH, EC, OC texture. analytical method was optimized quantification High Performance Liquid Chromatography (HPLC). contact time, adsorption/desorption isotherms, persistence both compounds with and/or studied. general, all sorption curves Trizine Trifuralin similar relatively low adsorption indicating that modifications not significant. kinetic process described Elovich model. Both present Koc value, however, different types adsorption, being moderate weak which implies could be distributed bodies as fixed matter. it should noted presents higher values ​​than samples, mean would less bioavailable than Trifluralin. Values ​​obtained Pearson correlation CO (%) % expected since, when observing results obtained Kd parameters soils herbicides, show parameter, compound soil. pesticides showed addition Kaolinite Humus increases half-life time herbicides. GUS index classified leachable samples.