不同栓皮栎家系对重金属的耐性和富集特性

Tolerance and Enrichment Characteristics of Different Families of Quercus variabilis to Heavy Metal

[目的]通过野外试验,评价栓皮栎家系在铅锌尾矿环境中的生长响应、重金属积累能力及土壤修复潜力。[方法]在杭州市富阳区废弃的铅锌尾矿库进行人工植被恢复试验,分析比较4个栓皮栎家系(泰山3号、泰山7号、泰山8号和徂徕山5号)在铅锌矿砂中生长3 a的生物量及其对营养元素和重金属的吸收及转移特征。[结果]4个栓皮栎家系在矿砂环境中均能生长,未表现出毒害效应。重金属胁迫下,栓皮栎家系各器官营养元素浓度表现出一定差异,且各家系均有较高的氮磷利用效率。研究表明参试栓皮栎家系体内重金属浓度较低,且各家系重金属生物富集系数(BCF)均小于0.100。除铅外,各家系重金属转移系数(TF)均大于0.50,表现出一定的重金属转移能力。泰山8号家系平均BCF和TF值均低于其它家系。[结论]3 a的长期试验表明,参试栓皮栎家系耐性较高、重金属生物富集系数和转移系数较低,可作为有潜力的污染土壤修复树种。

[Objective]A filed test was conducted to evaluate the growth response,enrichment and transfer characteristics to heavy metal and vegetation restoration prospect of four families from Quercus variabilis.[Method]Vegetation restoration test was carried out in the abandoned lead-zinc tailings for 3 years.The seedlings of four families(Taishan 3,Taishan 7,Taishan 8,and Julaishan 5)were transplanted into Pb/Zn mine tailing to compare their biomass,uptake and transfer characteristics of nutrient elements and heavy metals.[Result]The results showed that all the seedlings could survive in the Pb/Zn tailing and the toxicity symptoms was not observed.Under heavy metal stress,there were statistically significant differences among the seedlings of the four families according to the nutrient concentrations.Meanwhile,all families had high capability of utilization efficiency.Generally,the concentrations of heavy metals in different organs of Q.variabilis were low,and the values of bioconcentration factor(BCF)were less than 0.100.The values of translocation factor(TF)were more than 0.5,except Pb.The average BCF and TF values of family Taishan 8 were lower than those of the other families.[Conclusion]The results suggest that the families from Q.variabilis have high tolerance with the low BCF and TF,implying that they are better potential candidates for contaminated soil.