Cd-Pb复合污染条件下3种花卉植物的生长反应及超积累特性研究

Growing responses and hyperaccumulating characteristics of three ornamental plants to Cd-Pb combined pollution

采用水培实验方法,研究了3种耐性较强的花卉植物在Cd-Pb复合污染条件下的生长反应及可能的超积累特性.结果表明,花卉植物种不同,其对复合污染的生长反应也不同,它们的耐性大小顺序为蜀葵(AlthaearoseaCav.)>凤仙花(ImpatiensBalsaminaL.)>金盏菊(CalendulaofficinalisL.);Cd对植物生长的影响较大、Pb的影响相对较小.3种花卉植物对重金属的积累量都是根部大于地上部;蜀葵对重金属Cd具有很强的耐性和积累性,在Cd、Pb复合污染条件下极具植物修复的潜力.对于这3种花卉植物,Cd-Pb相互作用效应与多种因素有关,包括重金属之间的浓度组合、植物种和植株部位等,表现得极为复杂,不仅仅是单纯的加和、拮抗或协同作用.

Using the method of aquatic culture, the growing responses and accumulating characteristics of three ornamental plants with high tolerance to single Cd or Pb reported in the previous study were further investigated. The results showed that the growing responses of various ornamentals were different one another, depending on their species. The sequence of tolerance to the Cd-Pb combined pollution was Althaea rosea Cav. 〉 Impatiens Balsamina L. 〉 Calendula offtcinalis L. , and Cd had more effects on the growth of ornamentals, and Pb had less. The heavy metal accumulation in the roots was higher than that in the shoots of the three ornamentals. Althaea rosea Cav. had higher tolerance to Cd and could highly accumulate it, thus having a great application potential to phytoremediation of soil environment by Cd-Pb combined pollution. For the three ornamentals, the interactive effect of Cd and Pb was complicated, not simply additive, antagonistic and synergistic, but also related with many factors including various concentration combinations of heavy metals, plant species and different tissues.