模拟酸雨与Cd对紫萼膜脂过氧化及形态特征的影响

为了解酸雨与Cd复合污染对紫萼膜脂过氧化及形态特征的影响,本试验采用土培的方式,人工模拟pH分别为6.5,5.5,4.5,3.5,2.5梯度酸雨与不同浓度(0,10,30,50,100 mg/kg)Cd复合胁迫紫萼,从植物形态特征,质膜过氧化,抗氧化方面的响应研究复合污染对植物的生理生态影响特点。结果表明,复合污染比单一污染对植物伤害更大,二者间存在明显的交互作用,并非简单的加和作用,更多地表现为协同作用,高强度复合污染对紫萼的影响更大。紫萼对低强度酸雨和低浓度Cd污染有一定耐受性。Cd对植物的影响比酸雨更显著,是复合污染下造成植物伤害的主要因素。CAT活性对Cd污染比SOD敏感;Cd浓度为30 mg/kg和酸雨pH=3.5是植物可见伤害的临界值。综合各指标对复合污染的响应,紫萼可作为酸雨区土壤Cd污染背景下修复植物的选择。

Effects of simulated acid rain and Cd on the membrane lipid peroxidation and morphological characteristics of Hosta ventricosa

In order to better understand how acid rain and heavy metals work together to influence the membrane lipid peroxidation and morphological characteristics of Hosta ventricosa, in a soil culture experiment, different pH (6.5, 5.5, 4.5, 3.5 and 2.5) of acid rain and different concentrations (0, 10, 30, 50 and 100 mg/kg) of Cd were set to test how they influence morphological characteristics, lipid peroxidation and antioxidant activity of the plants. Compound pollutants had more influence on plants than with single pollutants. There was significant interaction between the acid rain and Cd. H. ventricosa showed some tolerance to low pH acid rain and low concentrations of Cd. However, acid rain combined with Cd caused a synergistic effect. The Cd influenced H. ventricosa more than acid rain, and as appeared to be a primary cause of plant damage. The CAT activity was more sensitive to Cd than SOD. Visible injury to plants was observed at 30 mg/kg of Cd and pH 3.5 of acid rain. All the indices indicated that H. ventricosa can be selected as the appropriate plant to remediate soils contaminated with Cd or affected by acid rain.