Abstract The effect of reed (Phragmites australis) and cattail (Typha angustifolia) extracts at different decomposition stages (fresh and dead) on the growth of a cyanobacterium, Microcystis aeruginosa, was investigated. Effective concentration 50 (EC50) of extracts were quantified based on dissolved organic carbon (C) concentration. The 100-day extract of fresh cattail showed the most inhibitory EC50 value of 19.3 mg C/L. We found that the fresh plant was more inhibitory than the dead plant for both species based on EC50 and the comparison of growth percentage in the maximum concentration of extracts, implying different compounds were produced during the time course of decomposition. The results of this study suggest that lake restoration efforts that include using emergent macrophytes to control nuisance algae should consider macrophyte life stage and decomposition time together with selecting macrophyte species, although further chemical identification is required to understand the allelochemical production in a variety of decomposition stages.

中文翻译：

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芦苇和香蒲提取物对蓝藻微囊藻生长的影响

摘要 研究了芦苇 (Phragmites australis) 和香蒲 (Typha angustifolia) 提取物在不同分解阶段（新鲜和死亡）对蓝藻微囊藻生长的影响。基于溶解的有机碳 (C) 浓度对提取物的有效浓度 50 (EC50) 进行量化。新鲜香蒲的 100 天提取物显示出最大的抑制性 EC50 值为 19.3 mg C/L。我们发现，根据 EC50 和提取物最大浓度下生长百分比的比较，新鲜植物比死植物对两个物种的抑制作用更强，这意味着在分解的时间过程中产生了不同的化合物。