In this article, we investigated effects of lead and cadmium on the biomass of ginkgo seedlings, and roles of the seedlings in accumulation characteristics of the heavy metals and remediation of the soil comtaminated by Cd 2+ or Pb2+ as well as their combination. The results showed that both Cd2 + and Pb2 + significantly or very significantly reduced biomass inurement of ginkgo seedlings, with Pb +more adverse than Cd2+. The Cd2+ - Pb2+ combined pollution further reduced biomass increment of ginkgo seedlings. The mass fractions and enrichment coefficient of Pb + and Cd + in ginkgo seedlings were in an order of root > stem > leaf, which was in favor of transportation Pb 2+ and Cd 2+ from root to stem and leave. The Cd 2+ - Pb compound pollution promoted ginkgo seedling absorbtion to Cd 2+ and Pb2+. The capacityof the upward transport of Pb2+ was greater than that of Cd2+ , which suggested an obvious dose-effect and synergistic effect. Cd2+ and Pb2+ accumulations in ginkgo seedlings were relatively large The accumulation in roots was higher than that in stems and leaves. The ability of the absorption, transportation and accumulation of ginkgo seedlings to Pb 2+was relatively greater under Cd 2+-Pb2+compound pollution. The phytoremediation efficiency of Cd 2+ and Pb2+ was relatively high.%研究重金属Pb2+,Cd2+污染及其复合污染土壤对盆栽银杏幼苗生物量的影响及银杏幼苗对重金属污染土壤中Pb2+和Cd2+的富集特性及土壤修复.结果表明:Cd2+,Pb2+可显著或极显著降低银杏幼苗单株及各器官生物量增量,Cd2+对银杏幼苗生物量增量的抑制作用较Pb2+小,Cd2+-Pb2+复合污染进一步降低了银杏幼苗单株及各器官生物量增量；银杏幼苗体内Pb2+,Cd2+的质量分数和富集系数均表现为根＞茎＞叶,有利于Pb2+和Cd2+向茎、叶部迁移；Cd2+-Pb2+复合污染可促进植株对Cd2+和Pb2+的吸收,且对Pb2+的向上转运能力大于Cd2+,表现出明显的剂量效应和协同作用；银杏幼苗对Cd2+,Pb2+具有较大的积累量,且根中Cd2+,pb2+累积量高于或显著高于茎、叶；Cd2+-Pb2+复合污染下银杏幼苗对Pb2+具有较强的吸收、运输和积累能力；银杏幼苗对Pb,Cd污染土壤的修复潜力较强.
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