作物根系-土壤系统中滴滴涕类化合物动态及影响因素

针对植物-土壤系统中滴滴涕及其代谢产物的动态情况及影响因素,开展了野外与室内相结合的研究工作。研究结果表明,相对于其他环境介质,农田土壤对以油菜和玉米为代表的作物中滴滴涕类化合物(DDTs)的富集起主要作用;油菜和玉米农作物根系和根际土中滴滴涕的浓度分别呈现增加和降低的动态。提高根表面积可以增加作物根系对DDTs的富集,并且在相同暴露条件下,根表面积的作用要大于土壤有机碳含量的作用。

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 characteristiets, 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.