Department of Forestry, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan.
J Environ Manage. 2011 Oct;92(10):2818-22. doi: 10.1016/j.jenvman.2011.06.032. Epub 2011 Jul 7.
Mahogany, a high biomass fast-growing tropical tree, has recently garnered considerable interest for potential use in heavy metal phytoremediation. This study performed hydroponic experiments with Cd concentration gradients at concentrations of 0, 7.5, 15, and 30 mg L(-1) to identify Cd accumulation and tolerance of mahogany (Swietenia macrophylla) seedlings as well as their potential for phytoextraction. Experimental results indicate that Cd inhibited mahogany seedling growth at the highest Cd exposure concentration (30 mg L(-1)). Nevertheless, this woody species demonstrated great potential for phytoextraction at Cd concentrations of 7.5 and 15 mg L(-1). The roots, twigs, and leaves had extremely large bioaccumulation factors at 10.3-65.1, indicating that the plant extracted large amounts of Cd from hydroponic solutions. Mahogany seedlings accumulated up to 154 mg kg(-1) Cd in twigs at a Cd concentration of 15 mg L(-1). Although Cd concentrations in leaves were <100 mg kg(-1), these concentrations markedly exceed the normal ranges for other plants. Due to the high biomass production and Cd uptake capacity of mahogany shoots, this plant is a potential candidate for remediating Cd-contaminated sites in tropical regions.
桃花心木是一种生物量大、生长迅速的热带树种，最近因其在重金属植物修复方面的潜在应用而引起了相当大的关注。本研究采用水培实验，设置 0、7.5、15 和 30mg/L 的 Cd 浓度梯度，以确定 Cd 对桃花心木（Swietenia macrophylla）幼苗的积累和耐受性及其用于植物提取的潜力。实验结果表明，在最高 Cd 暴露浓度（30mg/L）下，Cd 抑制了桃花心木幼苗的生长。然而，该木本物种在 Cd 浓度为 7.5 和 15mg/L 时表现出很强的植物提取潜力。根、枝和叶的生物积累因子均在 10.3-65.1 之间，表明植物从水培溶液中提取了大量的 Cd。在 Cd 浓度为 15mg/L 时，桃花心木幼苗在嫩枝中积累了高达 154mg/kg 的 Cd。虽然叶片中的 Cd 浓度<100mg/kg，但这些浓度明显超过其他植物的正常范围。由于桃花心木嫩枝的生物量产量和 Cd 吸收能力较高，因此该植物是修复热带地区 Cd 污染场地的潜在候选植物。
