Int J Phytoremediation. 2014;16(2):155-66. doi: 10.1080/15226514.2012.759534.
Here we report on the analysis of two aquatic plant species, Azolla caroliniana and Lemna minor, with respect to tolerance and uptake of co-occurring arsenic, copper, and silicon for use in engineered wetlands. Plants were cultured in nutrient solution that was amended with arsenic (0 or 20 microM), copper (2 or 78 microM), and silicon (0 or 1.8 mM) either singly or in combination. We hypothesized that arsenic and copper would negatively affect the uptake of metals, growth, and pigmentation and that silicon would mitigate those stresses. Tolerance was assessed by measuring growth of biomass and concentrations of chlorophyll and anthocyanins. Both plant species accumulated arsenic, copper, and silicon; L. minor generally had higher levels on a per biomass basis. Arsenic negatively impacted A. caroliniana, causing a 30% decrease in biomass production and an increase in the concentration of anthocyanin. Copper negatively impacted L. minor, causing a 60% decrease in biomass production and a 45% decrease in chlorophyll content. Silicon augmented the impact of arsenic on biomass production in A. caroliniana but mitigated the effect of copper on L. minor. Our results suggest that mixtures of plant species may be needed to maximize uptake of multiple contaminants in engineered wetlands.
在这里，我们报告了对两种水生植物物种，即满江红和浮萍，在用于人工湿地的共存砷、铜和硅的耐受和吸收方面的分析。植物在营养溶液中培养，该溶液中添加了砷（0 或 20 微摩尔）、铜（2 或 78 微摩尔）和硅（0 或 1.8 毫摩尔），单独或组合添加。我们假设砷和铜会对金属的吸收、生长和色素沉着产生负面影响，而硅会减轻这些压力。通过测量生物量的生长和叶绿素和花青素的浓度来评估耐受性。两种植物都积累了砷、铜和硅；浮萍通常在每生物质基础上的含量更高。砷对满江红产生负面影响，导致生物量产量减少 30%，并增加花青素的浓度。铜对浮萍产生负面影响，导致生物量产量减少 60%，叶绿素含量减少 45%。硅增强了砷对满江红生物量生产的影响，但减轻了铜对浮萍的影响。我们的结果表明，在人工湿地中，可能需要混合多种植物物种，以最大限度地吸收多种污染物。
