School of Environmental Science and Engineering, Shandong University , Jinan, 250100, China.
Shandong Provincial Engineering Center on Environmental Science and Technology, Jinan, 250061, China.
Environ Sci Technol. 2017 Nov 7;51(21):12774-12783. doi: 10.1021/acs.est.7b03085. Epub 2017 Oct 20.
This is the first study to systematically investigate the microbial community structure in cyanobacteria-laden drinking water sludge generated by different types of coagulants (including AlCl, FeCl, and polymeric aluminum ferric chloride (PAFC)) using Illumina 16S rRNA gene MiSeq sequencing. Results show that Cyanobacteria, Proteobacteria, Firmicutes, Bacteroidetes, Verrucomicrobia, and Planctomycetes were the most dominant phyla in sludge, and because of the toxicity of high Al and Fe level in AlCl and FeCl sludges, respectively, the PAFC sludge exhibited greater microbial richness than that in AlCl and FeCl sludges. Due to lack of light and oxygen in sludge, relative abundance of the dominant genera Microcystis, Rhodobacter, Phenylobacterium, and Hydrogenophaga clearly decreased, especially after 4 days storage, and the amounts of extracellular microcystin and organic matter rose. As a result, the relative abundance of microcystin and organic degradation bacteria increased significantly, including pathogens such as Bacillus cereus, in particular after 4 days storage. Hence, sludge should be disposed of within 4 days to prevent massive growth of pathogens. In addition, because the increase of extracellular microcystins, organic matter, and pathogens in AlCl sludge was higher than that in FeCl and PAFC sludges, FeCl and PAFC may be ideal coagulants in drinking water treatment plants.
这是第一项使用 Illumina 16S rRNA 基因 MiSeq 测序系统研究不同类型混凝剂（包括 AlCl、FeCl 和聚合铝铁氯化物（PAFC））生成的富藻饮用水污泥微生物群落结构的研究。结果表明，蓝藻、变形菌门、厚壁菌门、拟杆菌门、疣微菌门和浮霉菌门是污泥中最主要的门，由于 AlCl 和 FeCl 污泥中高 Al 和 Fe 水平的毒性，PAFC 污泥表现出比 AlCl 和 FeCl 污泥更高的微生物丰富度。由于污泥中缺乏光照和氧气，优势属微囊藻属、红杆菌属、苯基杆菌属和噬氢菌属的相对丰度明显下降，特别是在 4 天储存后，胞外微囊藻毒素和有机物的含量上升。结果，微囊藻毒素和有机降解菌的相对丰度显著增加，包括芽孢杆菌属等病原体，特别是在 4 天储存后。因此，污泥应在 4 天内处理，以防止病原体大量繁殖。此外，由于 AlCl 污泥中外源微囊藻毒素、有机物和病原体的增加高于 FeCl 和 PAFC 污泥，因此 FeCl 和 PAFC 可能是饮用水处理厂的理想混凝剂。
