Vertical variation of atrazine mineralization capacity in soils

the variation of atrazine mineralization capacity was investigated in two soil profiles selected with (adapted soil) and without (non-adapted soil) atrazine application history in córdoba, argentina. atrazine evolution was characterized by balance of 14c-u-ring atrazine radioactivity between mineralized, extractable and non-extractable fractions by means of incubations under laboratory conditions in two soil situations: with dry heat treatment (t105) and without heat treatment (control). the strong decrease of atrazine mineralization after microbial inactivation during all the incubation period in adapted soil suggests that the atrazine degraders were distributed throughout the entire adapted soil profile and were responsible for atrazine mineralization in subsurface horizons. in the non-adapted soil profile, the cometabolic process of mineralizing atrazine was corroborated. the atrazine mineralization capacity of subsurface horizons, where herbicide accumulation increases, should be considered and stimulated as a mechanism for the natural bioremediation of soils with frequent atrazine application.