Abstract: Rapes, which widely eaten by people, were selected as studying objects in this research, soil culture experiments was managed.We studied the absorbing and accumulating characters of heavy metals in rape under the pressure from different concentrations of heavy metals (cadmium, lead, mercury), and discussed the migration of heavy metals in soil-vegetable system.The results show that the absorbing and accumulating rules of different heavy metals in different parts of rape are different.The accumulation order of cadmium and mercury in the rape plants was ranged as roots >leaves >stems, and the accumulation order of lead in the rape plants was ranged as roots >stems >leaves.Rape roots have much stronger ability in accumulating heavy metals than stems and leaves, The adsorptive ability to heavy metals is:Cd >Hg >Pb.The contents of heavy metals in different parts of rape was significantly linearly correlated to the concentrations of heavy metals in the soil (r²>0.859).According to the national regulation about the maximum limit of heavy metals in edible parts of vegetables (GB 15201-1994, GB14935-1994, GB 2762-1994), the thresholds of cadmium, lead and mercury in soil for rape were 0.36 μg/g, 43.62 μg/g and 2.89 μg/g。

Key words: rape, cadmium, lead, mercury, absorption and accumulation

摘要： 以‘新选七叶’油菜为研究对象,采用土培方法,研究在不同浓度重金属(镉、铅、汞)胁迫下,油菜对重金属的吸收和积累特征,并探讨重金属在土壤—蔬菜间的迁移情况。结果表明:不同重金属在植物不同部位的分布和积累规律存在差异,镉和汞在植株上的积累规律为根> 叶> 茎,而铅在植株上的积累规律为根> 茎> 叶。油菜根部对重金属的累积能力远高于茎和叶,根部对三种重金属的吸收富集能力为镉> 汞> 铅。油菜各部位重金属含量与土壤重金属浓度呈显著正相关(r²>0.859)。以蔬菜可食部位重金属含量的最大限量为标准(GB 15201-1994、GB 14935-1994、GB 2762-1994),计算得出土壤中对应的镉、铅、汞临界值分别为0.362、43.62、2.892 μg/g。

关键词: 油菜, 镉, 铅, 汞, 积累吸收