光照度对蓝藻垂直迁移特性影响研究

The effect of light intensity on cyanophytes vertical distribution

通过水柱和摇瓶试验研究了蓝藻细胞胞内碳水化合物含量及蓝藻细胞在水体中的垂直分布对光照度变化的响应。结果表明,水柱试验中,在无光照和光照度为5000lx的条件下,铜绿微囊藻出现明显的表面浮聚现象,经过24h后,表层的藻细胞数分别占总藻细胞数的47%和26%;水柱试验中,在不同光照条件下,铜绿微囊藻胞内碳水化合物含量都呈现出表层低、底层高的现象;摇瓶试验中,水华鱼腥藻和铜绿微囊藻胞内碳水化合物含量对光照度的变化有很好的响应,光照度适量时,胞内碳水化合物含量上升,光照度不足或者过高时,胞内碳水化合物含量下降;光照度的变化能够在短时间内引起蓝藻细胞胞内碳水化合物含量变化,改变蓝藻细胞密度,从而影响到蓝藻细胞在水体中的垂直分布。

Batch of shake-flask experiments and water column experiments were conducted to cultivate the cyanophytes under different light intensities, and the effects of light intensity on algal Vertical distribution and its carbohydrate content were investigated. In the water column experiments, the Microcystis aeraginosa illuminated under 0 lx and 5 000 lx trended to assemble on the surface of water,after 24 h of cultivation,the surface algal holding to 47% and 26% of total algal number respectively,and the carbohydrate content in surface algal was higher than that in bottom algal. In the shake-flask experiments, Microcystis aeraginosa and Anabaena flosaquae presented better response to light intensity, algal growth under appropriate illumination owned higher carbohydrate content, excessively high or low light intensities could decrease algal carbohydrate content. Light intensity could influence the algal carbohydrate content and algal density in a short rime,and thus effected the algal vertical distribution.