为探索污染土壤边生产边修复技术的可行性,通过盆栽试验,采用植物修复的方法,将超富集重金属的植物土荆芥(Chenopodium ambrosioides L.)和农作物玉米/蚕豆间作在污染的土壤中,研究了土荆芥和蚕豆、玉米间作对植物吸收积累Pb、Cd和Zn的影响。结果表明:与单作相比,间作使土荆芥生物量提高了134%-217%,玉米生物量提高了100%-124%,蚕豆生物量提高了1.7%-5.6%。间作后土荆芥体内Pb含量增加了10%-85%,Cd含量增加了21%-134%,土壤有效态Pb、Cd含量增加了11%-19%,土荆芥的Pb、Zn转运系数都增加,Cd转运系数降低;与土荆芥间作后,玉米Pb含量降低了17%-33%,Zn含量降低了10%-34%,蚕豆Pb含量降低了27%-35%,Zn含量降低了5%-34%,根际土壤有效态Pb、Cd和Zn含量降低了2.5%-22.7%,玉米、蚕豆的Pb、Cd和Zn的转运系数均显著降低。研究结果表明:土荆芥和蚕豆、玉米间作促进了土荆芥对土壤中Pb、Cd和Zn的吸收和积累,同时抑制了作物体对重金属的吸收。
A phytoremediation system consisted of metal hyperaccumulator Chenopodium ambrosioides L. and crops (maize and broad bean) intercropped was exploited to phytoextract metals in polluted soil, in order to explore the feasibility of simultaneous grain production and heavy metal contaminated soil phytoremediation. Pot experiments were carried out to study the effects of intercropping Chenopodi- urn ambrosioides L. (C. ambrosioides) and crops (maize and broad bean) on the absorption and ac- cumulation of Cd, Pb and Zn in plant. The results showed that the biomass of C. ambrosioides, broad bean and maize increased by 134% - 217%, 100% - 124% and 1.7% - 5.6% under intercropping compared with monoculture, respectively. The contents of Pb and Cd in C. ambrosioides increased by 10% -85% and 21% - 134%. Besides, soil available Pb and Cd contents of C. ambrosioides in- creased by 11% and 19%. Then, the transfer coefficient of Pb and Zn in C. ambrosioides was in-creased, on the contrary, the Cd's reduced. On the other hand, the contents of Pb and Zn in maize de- creased by 17% -33% and 10% -34% respectively under intercropping system. Meanwhile, the contents of Pb and Zn in broad bean decreased by 27% -35% and 5% -34%. Furthermore, the a- vailable contents of Pb, Cd and Zn in rhizosphere soils decreased by 2.5% -22.7%. The transfer co- efficient of Pb, Cd and Zn in broad bean and maize was decreased significantly under intercropping system. The results indicate that contents of Pb, Cd and Zn in C. ambrosioides under intercropping system could be promoted and reduced in crops.