SORPTION OF S-TRIAZINES IN BRAZILIAN RAINFOREST SOILS

This research was conducted to evaluate the sorption of Ametryn, Atrazine, Simazine, Prometrine and Metamitron to soils from "Mata Atlantica" at Ubatuba region (Atlantic rainforest soils), employing the batch equilibrium approach. The herbicides were weakly retained in soils with low soil organic matter (SOM) content and thus presenting high potential to water contamination. All herbicides have shown high Koc at Typic Humaquepts soil, the higher in SOM content. The sorption isotherms for the herbicides at Typic Humaquepts soil suggested specific interactions between herbicides and SOM probably with partial protonation of herbicides followed by ion-exchange processes and/or hydrogen bonding formation of hydroxyl groups on the SOM surface.