调水对巢湖市河道水质的改善效果及对浮游藻类的影响

以巢湖市封闭河道为研究对象,采用水动力模型和生态动力学模型方法,结合野外围隔试验,探讨了调水对河道水质改善和水华抑制的作用效果,并通过调水试验对模拟结果进行了验证。计算出最优的调水周期,提出了合理的涵闸工程改造与科学的引排结合的措施。结果表明:调水能够使河道的水动力条件得到显著提高,平均流速均大于0.10 m/s,高于浮游植物生长临界流速,换水频率在21 d以内。通过一次调水试验表明模型的计算结果比较合理,科学合理的调水能达到抑制有害蓝藻水华在夏季暴发的目的。

Effect of water diversion on improvement of river water quality and phytoplankton in Chaohu

Taking Chaohu close river as research object,using the hydro and ecological dynamics model, the paper probed the effects of water divertsion on both water quality improvement and inhibition of algal bloom,and verified the simulation result through water diversion test. It used mathematical model to calculate the optimal cycle of water diversion and proposed the reasonable measures of integration of hydraulic structures rehabilitation/improvement with water diversion/draining.The results indicated that water diversion can significantly improve the hydrodynamic conditions in urban rivers, make the average flow velocity more than 0.10 m/s, which is higher than the critical flow velocity of phytoplankton growth.The frequency of water diversion should be within 21 days. The calculation result is more reasonable through a water transfer test. Therefore,the scientific and reasonable water diversion can reach the goal of restraining harmful algal blooms to outbreak in summer.