通过温室盆栽试验,研究珊瑚树对土壤中镉(Cd)的耐受和富集特征。研究结果表明,珊瑚树对污染土壤中Cd具有较强的耐受能力。培养56 d内,土壤中Cd含量对珊瑚树生物量影响不明显;随着培养时间的延长(105-203 d),珊瑚树的生长明显受到土壤中Cd的抑制作用。与对照处理(土壤中Cd含量为3.6 mg/kg)相比,培养154 d后,土壤中Cd含量为24.6 mg/kg处理下珊瑚树叶片中叶绿素a、叶绿素b、类胡萝卜素和丙二醛(MDA)含量没有明显变化;培养203 d后,土壤中Cd含量为24.6 mg/kg处理下珊瑚树叶片中类胡萝卜素和MDA含量无明显变化,但叶片中叶绿素a和叶绿素b含量明显受到抑制,从而导致珊瑚树叶片的生长明显受到抑制(P 〈 0.05)。培养203 d后,珊瑚树对土壤中Cd的富集系数和转运系数均大于1,表明珊瑚树对土壤中Cd具有一定的富集和转运能力。上述结果表明,珊瑚树对Cd污染土壤具有一定的生态修复潜力。
A pot experiment was conducted to study the tolerance and accumulation characteristics of Viburnum odoratissinum growing in cadmium (Cd)-contaminated soil. The results showed that V. odoratissinum had a strong tolerance to Cd in contaminated soil. The biomass of V. odoratissinum was slightly changed by the soil Cd content within 56 days cultivation. With extended cultivation time (105-203 d), the growth of V. odoratissinum was obviously inhibited by the soil Cd content. After 154 days of cultivation, when the content of Cd in soil was 24.6 mg/kg, the contents of chlorophyll a, chlorophyll b, carotenoid and malondialdehyde (MDA) in fresh leaves of V. odoratissinum were slightly different from that of the control. After 203 days of cultivation, the carotenoid and MDA contents in fresh leaves increased slightly, whereas the chlorophyll a and chlorophyll b contents was obviously inhibited. Especially, the leaf growth of V. odoratissinum was inhibited significantly (P 〈 0.05) when the Cd content in soil was 24.6 mg/kg. Moreover, the accumulation and transferring factors of V. odoratissinum for Cd in the soil were more than 1 after 203 days of cultivation. The results suggested that V. odoratissinum is helpful for Cd-contaminated soil ecoremediation.