不同种植密度的黑藻在城市河道中净化效果的模拟

在流速为1.74 cm/s的较低动水条件下,设置3组黑藻种植密度,ρ1、ρ2和ρ3分别为0.9、1.9和3.0株/dm ²,模拟不同密度的黑藻对城市河道水质的净化效果。结果表明,与ρ1和ρ3组相比,ρ2组对NH₃-N、COD_Cr和TP的净化均有优势,其平均去除率分别为87.79%、67.43%和82.48%;试验结束后,水质由原GB 3838—2002《地表水环境质量标准》地表Ⅴ类水质净化为Ⅲ类水质。说明在较低流速水环境中黑藻的种植密度以1.9株/dm ²的净化效果为佳。

Simulation of purification effect of Hydrilla verticillata of different planting densities in urban rivers

Under the moving water condition with low water flow of 1.74 cm/s, three planting densities of Hydrilla verticillata were set, including 0.9(ρ1) and 1.9(ρ2) and 3.0/dm 2 (ρ3), respectively. The purification effect of different planting densities of Hydrilla verticillata for urban river water was simulated. The results showed that compared with ρ1 experimental group and ρ3 experimental group, the ρ2 experimental group had the superiority in purification of NH3-N, CODCr and TP, with the average removal rate of 87.79%, 67.43% and 82.48%. According to the Environmental Quality Standards for Surface Water(GB 3838-2002), after the experiment, the original surface water was purified from Classification Ⅴ to Classification Ⅲ. It was demonstrated that the Hydrilla verticillata with planting density of 1.9/dm 2 had better purification effect, under the low water flow condition.