水位调度对高原湖库水源地浮游藻类的影响模拟

Simulation on impact of water level regulation on phytoplankton in water source of plateau lakes and reservoirs

高原湖库饮用水源地多面临严重的富营养化问题,探寻高效的生态调度控藻技术是解决此问题的关键,水位调度是其中最为经济和有效的调控方式之一。基于MIKE 3构建了湖库三维水动力-水质生态耦合模型,以红枫湖为例,开展了水位调度对高原湖库水源地浮游藻类的影响预测研究。结果表明:水位对湖区藻类生长聚集具有明显的调节作用,其中红枫湖区的流场在水位突降期间明显增加,在南湖与北湖连接段的流速普遍增加至0.3 m/s以上,而这种水动力引起的扰动对打破藻类结构、减少湖区的藻生物量具有明显的效果,红枫湖南湖的藻浓度大幅下降。另外,库区长时间稳定在低水位运行对于藻类防控具有十分不利的影响。

Most of the drinking water sources in plateau lakes and reservoirs are facing serious eutrophication,and the key to solving this problem is to explore efficient ecological algae control technology.Water level regulation is one of the most economical and effective regulation methods in reservoir phytoplankton regulation.Based on MIKE 3,this paper constructs a 3D hydrodynamic-water quality ecological coupling model for lakes and reservoirs,and carries out a prediction study on the impact of water level regulation on phytoplankton in the water source areas of plateau lakes and reservoirs.The study shows that the water level has an obvious regulating effect on the growth and accumulation of algae in the lake area.Among them,the flow field in the Hongfeng Lake area increased significantly during the sudden drop of water level,and the flow velocity in the connecting section between the South Lake and the North Lake generally increased up to more than 0.3m/s,while the disturbance caused by this hydrodynamic force had obvious effect on breaking the algae structure and reducing the algae biomass in the lake area,and the algae concentration in southern area of Hongfeng Lake decreased significantly.In addition,the long-term stable operation at low water levels in the reservoir area has a very adverse impact on algae prevention and control.