Dynamics of Dichloro-Diphenyl-Trichloroethanes in the Plant Root-soil System and the Influencing Factors

The availability of the environmental organochlorine pesticides (OCPs) to the plant roots depends on many factors including soil physicochemical characteristicts, e.g. total organic carbon (TOC) and plant physiological characters, e.g. root surface area. To investigate the dynamic distribution of OCPs in the rootsoil system and the influencing factors, DDT and its metabolites were selected as representing compounds. Field work and interior pot experiments were together carried out to meet the targets. According to the results from the study, it was concluded that the land soil influenced more on DDTs′ accumulation in plant roots (such as rape and corn) than other environmental media and the accumulation of DDTs in the soil and the roots showed a reverse dynamic state. The increase of root surface area would facilitate DDTs enrichment on the plant root, while increase of soil TOC inhibits the availability of DDTs to plant roots.