摘要
为研究紊流水体中藻类的垂向分布特性,依据三峡水库次级河流回水段的水动力状况,自行设计了水流实验装置,选取次级河流回水区水华高发时段的气候状况和营养盐水平为实验条件,研究了雷诺数对蓝藻、绿藻和硅藻垂向分布的影响以及雷诺数对不同水深处藻类的悬浮和聚集行为的作用.研究结果表明:在水温为20℃、光照强度为5000 lx的富营养水体中,当断面平均流速在0～0.005 m/s、雷诺数在0～1750时,蓝藻主要悬浮聚集在0.2～0.8 m的表层水体中;而当断面平均流速在0.1～0.5 m/s、雷诺数在35000～175000时,硅藻主要悬浮聚集在0.2～0.8 m的表层水体中;与蓝藻和硅藻相比,绿藻适宜的雷诺数范围更宽,当断面平均流速在0～0.05 m/s、雷诺数在0～17500时,绝大部分的绿藻都能悬浮聚集在0.2～0.8 m的表层水体中.
Through a self-designed experimental device according to hydrodynamic conditions of backwater area of branch of Three Gorges Reservoir, the experiment was carried out to study the effects of reynolds number and turbulent flow on the vertical distributions of algae and its suspension and gathered behavior in different water depths. In the condition that water temperature is 20℃, illumination is 5000 lx and there are enough nutrient concentrations in water, the experiment results showed that Cyanophyta ceils are mainly in the depth ranging from 0.2 m to 0.8 m when average flow velocity is within 0 - 0. 005 m/s and reynolds number is within 0 - 1750 while Bacillariophyta cells are mainly in the depth ranging from 0.2 m to 0.8 m when average flow velocity is within 0.1 -0.5 m/s and reynolds number is within 35000 - 175000. Compared to Cyanophyta and Bacillariophyta, a considerable part of Chlorophyta cells could suspend in the depth ranging from 0.2 m to 0.8 m when flow velocity is within 0 - 0.05 m/s and reynolds number is within 0 - 17500.
出处
《湖泊科学》
CAS
CSCD
北大核心
2012年第5期717-722,共6页
Journal of Lake Sciences
基金
国家水体污染控制与治理科技重大专项项目(2009ZX07104-002)
国家自然科学基金项目(51009155)
重庆市自然科学基金项目(CSTC
2011BB7085)联合资助
关键词
雷诺数
紊流
藻类
垂向分布
三峡水库
Reynolds number
turbulent flow
algae
vertical distribution
Three Gorges Reservoir
