Arsenic species and leachability in the fronds of the hyperaccumulator Chinese brake (Pteris vittata L.).
Arsenic species and leachability in the fronds of the hyperaccumulator Chinese brake (Pteris vittata L.).
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DOI：
10.1016/s0269-7491(02)00470-0
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发表时间：
2003-07
影响因子：
8.9
通讯作者：
C. Tu;L. Ma;Weihua Zhang;Yong Cai;W. Harris
中科院分区：
文献类型：
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作者：
C. Tu;L. Ma;Weihua Zhang;Yong Cai;W. Harris
砷的形态分析不仅对了解砷的积累和高砷解毒机制具有重要意义，而且对设计富砷生物质的处置方案也很重要。本研究的主要目的是了解中国凤尾蕨（Pteris vittata L.）叶片中砷的形态分布和可吸收性，一个砷超富集植物，强调对富砷生物质处置的影响。中国制动器生长18周的土壤中添加了50毫克砷kg−1as砷酸盐（AsO 43 −），亚砷酸盐（AsO 33 −），二甲基胂酸（DMA），或甲基胂酸（MMA）。植物样品用甲醇/水（1：1）提取，用高效液相色谱-原子荧光光谱法进行砷形态分析。在实验室条件下，研究了风干处理对砷形态和砷吸附能力的影响。18周后，水溶性砷在土壤中主要是存在的砷酸盐与很少检测到的有机物种或亚砷酸盐，无论砷物种添加到土壤中。然而，砷在叶中主要以无机亚砷酸盐的形式存在，平均为94%。亚砷酸盐再氧化发生在老叶和切除的干燥组织。土壤中砷的形态对叶片中砷的形态影响不大。空气干燥的叶子导致大量的砷浸出。从二次污染的角度考虑富砷生物质的处置方案时，这些发现可能具有重要意义。
Arsenic speciation is important not only for understanding the mechanisms of arsenic accumulation and detoxification by hyperaccumulators, but also for designing disposal options of arsenic-rich biomass. The primary objective of this research was to understand the speciation and leachability of arsenic in the fronds of Chinese brake (Pteris vittata L.), an arsenic hyperaccumulator, with an emphasis on the implications for arsenic-rich biomass disposal. Chinese brake was grown for 18 weeks in a soil spiked with 50 mg As kg−1as arsenate (AsO43−), arsenite (AsO33−), dimethylarsinic acid (DMA), or methylarsonic acid (MMA). Plant samples were extracted with methanol/water (1:1) and arsenic speciation was performed using high performance liquid chromatography coupled with atomic fluorescence spectrometry. The impacts of air-drying on arsenic species and leachability in the fronds were examined in the laboratory. After 18 weeks, water-soluble arsenic in soil was mainly present as arsenate with little detectable organic species or arsenite regardless of arsenic species added to the soil. However, arsenic in the fronds was primarily present as inorganic arsenite with an average of 94%. Arsenite re-oxidation occurred in the old fronds and the excised dried tissues. Arsenic species in the fronds were slightly influenced by arsenic forms added to the soil. Air-drying of the fronds resulted in leaching of substantial amounts of arsenic. These findings can be of significance when looking at disposal options of arsenic-rich biomass from the point of view of secondary contamination.