Characteristics of the phytoplankton community and bioaccumulation of heavy metals during algal blooms in Xiangjiang River (Hunan, China)
Characteristics of the phytoplankton community and bioaccumulation of heavy metals during algal blooms in Xiangjiang River (Hunan, China)
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DOI：
10.1007/s11427-011-4222-6
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发表时间：
2011-10
期刊：
影响因子：
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通讯作者：
J. Li;F. Peng;Dongbo Ding;Shubing Zhang;Deliang Li;Z. Ting
中科院分区：
文献类型：
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作者：
J. Li;F. Peng;Dongbo Ding;Shubing Zhang;Deliang Li;Z. Ting
湘江（中国湖南）是中国污染最严重的河流之一，在湘江的中下游地区，藻华发生的频率有所增加。我们确定了2010年9月中下旬发生的水华形成物种。此外，我们确定了金属在藻类中的生物积累的程度，并使用小鼠生物测定法测量了藻类的毒性。在上游（永州）、中游（衡阳）和下游（株洲、湘潭和长沙）采集水样。优势种为颗粒凹链藻（Aulacoseira granulata），以前称为颗粒直链藻（Melosira granulata）。最严重的水华发生在湘潭和长沙，这两个城市的A. granulata的最高值为1.3×10（5）丝状体L（-1），叶绿素a为0.04 mg L（-1）。浮游植物中Al、Fe和Mn的含量分别为4.4×10（3）、768.4和138.7 mg kg（-1）干重。生物富集系数分别为4.0×10（5）、7.7×10（5）和3.2×10（3）。重金属Pb的生物富集能力最强，其含量为19.2 mg kg（-1）干重，生物富集系数为9.6× 103。小鼠生物测定表明，水华是有毒的。LD（50）为384 mg kg（-1），所有存活的小鼠在暴露后的前72小时内体重减轻。结果表明，A.重金属污染河流中的颗粒虫对淡水生态系统和人类健康构成威胁。因此，应采取措施控制此类河流的富营养化和重金属污染。
The frequency of algal blooms has increased in the mid and downstream reaches of the Xiangjiang River (Hunan, China), one of the most heavily polluted rivers in China. We identified the bloom-forming species in a bloom that occurred mid-late September 2010. In addition, we determined the extent of metal bioaccumulation in the algae and measured the toxicity of the algae using a mouse bioassay. Water samples were collected at upstream (Yongzhou), midstream (Hengyang), and downstream (Zhuzhou, Xiangtan, and Changsha) sites. The dominant species was Aulacoseira granulata, formerly known as Melosira granulata. The heaviest bloom occurred at Xiangtan and Changsha, where the number of A. granulata peaked at 1.3×10(5) filaments L(-1) and chlorophyll a at 0.04 mg L(-1). Concentrations of Al, Fe, and Mn were 4.4×10(3), 768.4, and 138.7 mg kg(-1) dry weight in the phytoplankton. The bioaccumulation factor was 4.0×10(5), 7.7×10(5), and 3.2×10(3), respectively. The heavy metal Pb had the greatest tendency to bioaccumulate among the highly toxic heavy metals, with a concentration of 19.2 mg kg(-1) dry weight and bioaccumulation factor of 9.6×10(3). The mouse bioassay suggested the bloom was toxic. The LD(50) was 384 mg kg(-1) and all surviving mice lost weight during the first 72 h after exposure. Our results demonstrate that blooms of A. granulata in rivers contaminated with heavy metals pose a threat to freshwater ecosystems and human health. Thus, measures should be taken to control eutrophication and heavy metal pollution in such rivers.