芦苇秆浸出液抑藻的最佳环境条件研究

应用全面正交设计试验方案，研究了三种主要环境因子温度、pH、氮磷比及其互作对芦苇秆浸出液抑制铜绿微囊藻（Microcystis aeruginosa）生长的影响。结果表明:芦苇秆浸出液使藻细胞出现聚集现象，对铜绿微囊藻细胞密度和叶绿素a的含量变化的影响均与这三个环境因子及其互作显著相关，温度是影响抑藻的主效环境因子，其次是pH和氮磷比，温度与pH以及温度与氮磷比之间也存在一定的交互作用，pH与氮磷比之间无显著差异。具体表现为，低温组（10℃）抑藻效果显著，随着温度升高抑藻效果逐渐减弱，pH和氮磷比对抑藻效果的影响都与温度水平密切相关，所有的低温组（10℃）及大部分中温组（18℃）的温度、pH、氮磷比各水平均与高温组（25℃）之间存在显著差异（P0.05）。经过方差综合分析，芦苇秆浸出液抑藻的最佳环境条件为:温度为10℃，pH为9，氮磷比为2，在此条件下连续培养7d后，藻细胞密度下降到原来的40.48%，叶绿素a下降到原来的51.26%，故推测芦苇秆应用于控制水华的发生及水体蓝藻污染的恢复具有良好应用前景。  

A RESEARCH ON OPTIMUM CONDITIONS FOR ALGAL INHIBITION BY REED EXTRACT

Orthogonal experiment design was taken for the research of the interactions among temperature, pH and N/P ratio and their inhibitory effects on Microcystis aeruginosa. The results showed that reed extract led to gathering in algae cells, and its effects on algae cells and the density of Microcystis aeruginosa cells and the variation of amount of chlorophyll a were both relative to the three above-mentioned factors. Temperature was the major factor affecting the inhibitory effect, and then were pH and N/P ratio. There were also interactions between temperature and N/P ratio. But there was no distinct difference between pH and N/P ratio. The specific phenomena were that the low temperature group (10℃) showed the most distinctive inhibitory effect, the inhibitory effect declined with the temperature rose, and the pH and N/P ratio were both closely connected with the temperature in their inhibitory effects. Levels of temperatures of all low temperature groups (10℃) and temperatures, pH and N/P ratio of most medium temperature groups (18℃) were distinctly different from those of the high temperature groups (25℃) (P0.05). According to various analysis the best condition for reed extract's inhibitory effect on M. aeruginosa was at 10℃, pH value equals 9 and N/P ratio equals 2.Seven days after continuous cultivating under such environment, the density of algae cells decreased to 40.48%, and the chlorophyll a content decreased to 51.26%. This result showed that reed stalk lixivium was effective to reduce the chance of algal bloom happening and helpful in recovering from blue-green algae pollution.