To make the effluent of constructed wetlands in a pond recirculating aquaculture system satisfy aquaculture requirent, a 150m in length, 0.5m in width and 0.6m in depth ecological ditch was constructed on the basis of the periphyton reactor theory. The reoxygenation and deep purification effect of the ditch on the effluent of constructed wetlands was explored in this study. The results showed that the level of dissolved oxygen (DO) in the effluent of constructed wetlands increased to a range of 4.41-7.91 mg/L and pH value increased significantly by flowing though the ecological ditch (P ＜0.05). DO level in the water of ecological ditch increased linearly with the length of the ditch within the range of 150 m (P ＜0.05). The ecological ditch deeply purified NH4+-N, IMn and PO43--P in the effluent of the constructed wetlands with removal rate of 19.46％, 13.38％ and 31.09％, respectively. The total coliform group was also eliminated with removal rate fluctuating between 12.5％ and 78.13％. These results indicated that the ecological ditch based on periphyton reactor could increase DO level and further reduce N, P content of the effluent from the constructed wetlands. The ecological ditch can be used as a matching water reuse system of constructed wetlands.%为使池塘循环水养殖系统中人工湿地出水更加满足养殖水质要求,在长×宽×深为150 m×0.5 m×0.6 m的养殖池塘排水沟内借助固着藻类反应器原理设计构建了生态沟渠,研究了生态沟渠对人工湿地出水溶氧恢复状况及深度净化效果.研究结果显示,人工湿地出水溶氧经过生态沟渠后显著提高至4.41～7.91 mg/L,pH值显著提高(P＜0.05).在150 m长度范围内,生态沟渠水中溶氧量随着沟渠长度的增加呈线性增加的趋势(P＜0.05).生态沟渠对人工湿地出水中NH4+-N、IMn和PO43--P等具有进一步去除效果,去除率分别达19.46%、13.38%和31.09%,对总大肠菌群的去除率范围在12.5%～78.13%.上述结果表明基于固着藻类反应器的生态沟渠能使人工湿地出水溶氧低的状况得到改善,N、P等物质得到进一步去除,可以作为与人工湿地配套的水回用系统.
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