【摘要】 化感作用是水生植物与浮游藻类竞争的重要手段。通过沉水植物与铜绿微囊藻共培养以及沉水植物种植水单独培养铜绿微囊藻实验,研究了南四湖广泛分布的3种沉水植物菹草、光叶眼子菜和金鱼藻对铜绿微囊藻的化感作用。结果表明,在排除营养及光照条件限制的前提下,3种沉水植物与铜绿微囊藻共培养时都能抑制铜绿微囊藻的生长,但抑制作用的强弱与沉水植物的种类和生物量以及藻类初始密度相关,生物量为10 g/L和5 g/L时,菹草对低起始浓度的铜绿微囊藻抑制作用较明显,而对于高起始浓度的铜绿微囊藻,菹草生物量为10 g/L时抑制作用较强,菹草生物量为5 g/L时抑制作用较弱;光叶眼子菜生物量为7 g/L和4 g/L时,对两种起始密度铜绿微囊藻的生长均有强烈的抑制作用;金鱼藻生物量为7 g/L和4 g/L时,对低起始密度的铜绿微囊藻抑制作用明显,而对高起始密度的铜绿微囊藻抑制作用比较弱。3种沉水植物对铜绿微囊藻的抑制作用强弱顺序依次为:光叶眼子菜>菹草>金鱼藻。实验中3种沉水植物的种植水对铜绿微囊藻的生长均有促进作用。更多还原

【Abstract】 Allelopathy is an important trait in competition between macrophytes and phytoplankton in freshwater ecosystems.Allelopathic effects of submerged macrophytes such as P.crispus,P.lucens,and C.demersum on Microcystis aeruginosa were assessed using co-culture experiments under controlled laboratory conditions.Excluding the influence of nutrient and light intensity condition,the results showed that all three macrophytes had significant allelopathic effects on the growth of M.aeruginosa,and the effects depended on initial algae cell density,the species and biomass of the macrophyte.The growth of M.aeruginosa was significantly inhibited by 10 g/L and 5 g/L of P.crispus at low initial cell density.At high initial cell density 10 g/L P.crispus showed a more inhibitory effect on M.aeruginosa than 5 g/L P.crispus.The allelopathic effects of 7 g/L and 4 g/L P.lucens on M.aeruginosa at two initial cell densities were very significant.Both 7 g/L and 4 g/L C.demersum had significant growth inhibition on M.aeruginosa at low initial cell density,while less effects were observed at high initial cell density.The allelopathic effects of the three submerged macrophytes increased as P.lucens>P.crispus>C.demersum.In an experiment of the three submerged macrophytes culture filtrates,culture water showed stimulatory growth effects on M.aeruginosa.更多还原