铅锌胁迫下轮叶黑藻的吸附水平及生理响应

THE EFFECTS OF LEAD-ZINC STRESS ON ADSORPTION AND PHYSIOLOGICAL RESPONSE OF HYDRILLA VERTICILLATE

为探讨铅锌胁迫下轮叶黑藻(Hydrilla verticillate)的吸附水平及生理响应,分别设置不同Pb^(2+)(浓度梯度为0、0.01、0.05、0.10和0.20 mg/L)、Zn^(2+)(浓度梯度为0、0.05、1.00、2.00和4.00 mg/L)浓度单一和复合胁迫轮叶黑藻28d,测定其对铅锌的吸附量,叶绿素a、叶绿素b、丙二醛(MDA)和总抗氧化能力(T-AOC)含量,以及超氧化物歧化酶(SOD)和过氧化物酶(POD)的活性变化。结果显示:高浓度(≥1.00 mg/L)的Zn^(2+)可促进轮叶黑藻对Pb^(2+)的吸收,对Zn^(2+)的吸附主要受Zn^(2+)处理浓度的影响;低浓度Pb^(2+)和Zn^(2+)可以促进叶绿素的合成,高浓度(浓度≥1.00 mg/L)胁迫则抑制叶绿素的合成;受到胁迫时其抗氧化系统会迅速作出反应,但一定浓度的Pb^(2+)与Zn^(2+)在单一和复合胁迫下,抗氧化系统受限,说明抗氧化系统不能正常运转,机体受到损伤。研究结果为轮叶黑藻在重金属修复中的应用提供一定的理论依据。

To investigate the adsorption and physiological response of Hydrilla verticillate under lead-zinc stress,H.verticillata were stressed by lead(Pb^(2+):0,0.01,0.05,0.10 and 0.20 mg/L)and zinc(Zn^(2+):0,0.05,1.00,2.00 and 4.00 mg/L)with single and composite process for 28 days to measure the adsorption of Pb^(2+),Zn^(2+),chlorophyll a,chlorophyll b,malondialdehyde(MDA),total antioxidant capacity(T-AOC),superoxide dismutase(SOD)and peroxidase(POD)activity.The result showed that the Zn^(2+) absorption was Zn^(2+)concentration-dependent,and the high concentration of Zn^(2+) (≥1.00 mg/L)promoted the Pb^(2+) absorption by H.verticillata;The low concentration of Zn^(2+) and Pb^(2+) promoted the synthesis of chlorophyll,while high concentration(≥1.00 mg/L)inhibited the synthesis of chlorophyll.Pb^(2+)and Zn^(2+)significantly mediated antioxidant indexes of H.verticillata to damage the organism.The results of this study will provide a theoretical basis for application of H.Verticillata in heavy metal remediation.