摘要
为了解Cu/Zn复合胁迫对不同乔木抗氧化能力的影响,采用土培法模拟重金属污染环境,研究了Cu/Zn单一及复合重金属胁迫对广玉兰(Magnolia grandiflora)、柳树(Salix babylonica)的过氧化物酶(POD)和过氧化氢酶(CAT)活性、脯氨酸(Pro)和丙二醛(MDA)含量的影响。结果表明,单一Cu胁迫对广玉兰、柳树的伤害作用较单一Zn胁迫严重;Cu/Zn复合胁迫下,2种乔木抗氧化指标均在Cu15和Zn110时达到最大值,表现出较强的抗性,而后随着复合浓度增加,重金属对其毒害作用增大。在75 mg/L Cu与210 mg/L Zn单一及复合胁迫下,随胁迫时间延长,广玉兰细胞活性氧代谢失衡,POD、CAT活性急剧上升,第7天时分别达到Cu(1 243.89%,300.00%)、Zn(149.22%,60.00%)、Cu/Zn(653.96%,170.00%)。柳树则无法承受高浓度、长时间的Cu、Zn伤害而死亡。综合分析,广玉兰较柳树对重金属抗性强。
In order to understand the effect of the combined stress of Cu and Zn ions on two kinds of trees, the effects of the single and combined stress of Cu and Zn on the activities of peroxidase （POD） and eatalase （CAT）, as well as the contents of proline（Pro） and malondialdehyde（MDA） in Magnolia grandiflora and Salix babylonica were investigated in the simulated test, in which the pollution of heavy metals in soil was simulated by soil cultivation. The result indicated that the harm of single stress with Cu to Magnolia grandiflora and Salix babylonica was more obvious than that of the single stress of Zn. In the combined stress with Cu and Zn, the antioxidantic indices in the two kinds of trees reached the maximum value at Cul5 and Zn110, and the two kinds of trees showed the strong resistance. And then the toxic effects of heavy metals increased with increasing the combined concentration of heavy metals. Under the single and combined stress of Cu（75 mg/L） and Zn（210 mg/L）, the balance of oxygen metabolism in Magnolia grandiflora cell lost with prolonging the stress time. Meanwhile, the activities of POD and CAT increased dramatically, and they increased 1 243.89%, 300.00% by Cu, 149.22%, 60.00% by Zn and 653.96%, 170.00% by Cu/Zn on the seventh day, respectively. But Salix babylonica could not stand the harm of Cu（75 mg/L） and Zn（210 mg/L） at the high concentration, and then died. In addition, Magnolia grandiflora has stronger resistance to heavy metals than Salix babylonica.
出处
《城市环境与城市生态》
CAS
2013年第1期25-28,共4页
Urban Environment & Urban Ecology
基金
科技部十二五水体污染与治理科技重大专项(2012ZX07101-013)
江南大学大学生创新项目(JD2011-05)资助
关键词
广玉兰
柳树
Cu
Zn复合胁迫
抗氧化能力
Magnolia grandiflora
Salix babylonica
combined stress of Cu and Zn
antioxidantic ability
