不同光照下微囊藻垂直迁移模拟研究

通过室内模拟不同光照条件下微囊藻水华的垂直迁移过程,分析了光强对微囊藻细胞在水柱中聚集和悬浮的影响。结果表明:不同光源下水柱中微囊藻细胞发生垂直迁移,并明显聚集于中下层;I2光源下微囊藻细胞垂直迁移速度高于其他处理,高达2.59 m/h;微囊藻细胞在弱光条件下,通过形成伪空泡使其细胞密度降低、浮力增大,从而悬浮于水柱中,寻找适宜生境;野外水域中以微囊藻为优势藻种的蓝藻水华正是通过在强光条件下伪空泡破裂下沉、弱光条件下伪空泡增多上浮的趋利避害机制而产生。

Simulation on Vertical Migration of Microcystis sp.under Different Illuminations

Through the simulation of vertical migration of Microcystis sp.in the laboratory,effect of different illuminations on distribution,gathering,floating and vertical migration of Microcystis sp.was analyzed.Results showed that algae cells migrated vertically and gathered in the middle-under layers,wherein had higher content of Chlorophyll a.The vertical migration velocity with illumination of I2 was higher than those of other illuminations,which was about 2.59 m/h.Under low light conditions,the characteristic gas-filled structures were formed in the algae cells of Microcystis sp.,which led to decrease of cell density and increase of buoyancy,therefore helped the algae cells floating in water columns and seeking available habitat.Microcystis sp.can adapt to the different illuminations to draw on advantage and avoid disadvantage,which is responsible for the occurrence of cyanobacterial bloom with the preponderant Microcystis sp.in the field.