群体大小对微囊藻细胞昼夜垂向迁移的影响

针对群体形态对微囊藻昼夜间上浮下沉规律的影响问题,利用柱状培养装置对室内培养的单细胞、群体细胞以及在太湖采集的群体细胞进行了昼夜间分层观测实验,探讨了细胞形态对微囊藻垂向迁移的影响.实验结果表明:单细胞表现出一定的昼夜迁移规律,但无论是室内培养群体细胞还是太湖采集的群体细胞,都未观察到显著的昼夜上浮下沉的变化规律.另一方面,太湖采集的群体细胞表现出显著的漂浮特点.由此认为,室内培养的细胞与实际湖泊细胞之间存在比重上的差异,群体的大小对于上浮有明显的影响.

Effect of colony size on Microcystis diurnal vertical migration

The diurnal migration of Microcystis was studied using a cylindrical reactor to demonstrate how colony morphology affects the tendency of Microcystis cells to float or sink.Experiments were carried out using single cells and colonies from laboratory incubation and also colonies from Lake Taihu.Results showed that single cells had significant diurnal migration while this was apparently insignificant in colonies either from laboratory incubation or natural water.In contrast,colonies taken from Lake Taihu exhibited remarkable floating features.These were observed to be due to differences in specific gravity between cells from laboratory incubation and Lake Taihu.In addition,colony morphology affects significantly the upward movement of the cells.