温度、光照及藻细胞密度对3种水华蓝藻生长及竞争的影响

Effects of temperature,illumination and cell density on growth and competition of three species of water-bloom cyanobacteria

以铜绿微囊藻(Microcystis aeruginosa Kutzing)、细小平裂藻(Merismopedia minima G.Beck)和土生伪鱼腥藻(Pseudanabaena mucicola(Naumann&Huber-Pestalozzi)Schwabe 1964)为研究对象,运用单因子和正交实验的方法,分析了温度、光照以及藻细胞初始密度对三者生长及竞争的影响.结果表明:铜绿微囊藻和细小平裂藻均能在高温、高光照的条件下达到最佳生长状态;黏伪鱼腥藻只有在低温、低光照的情况下才具有竞争优势.在相同的温度和光照条件下,不同的藻细胞初始密度是其竞争获得优势藻种地位的关键因子.除了控制营养盐和其他污染物的输入外,关注浮游植物群落结构变化,控制和降低蓝藻在水华爆发前的生物量密度,是治理淡水湖泊(水库)蓝藻水华的有效方法.

The effects of temperature,illumination and initial algae cell density on growth and competition of Microcystis aeruginosa,Merismopedia minima and Pseudanabaenamucicola were studied by the method of single factor experiment and orthogonal experiment.The results showed that both M.aeruginosa and M.minimacould grow optimally under higher temperature and/or higher illumination.P.mucicola has competitive advantage only under lower temperature and lower illumination.Under the same temperature and illumination conditions,the initial density of algae cells is the key factor for competing the dominant species position.In addition to controlling the input of nutrients and other pollutants,paying attention to the changes of phytoplankton community structure,controlling and reducing the biomass of cyanobacteria before the water blooms may be another effective way to control cyanobacterial blooms in freshwater lakes or reservoirs.