[Objective] This study aimed to make the effluent of constructed wetlands in a pond recirculating aquaculture system satisfy aquaculture requirements. [Method] A 150 m long, 0.5 m wide and 0.6 m deep ecological ditch ...[Objective] This study aimed to make the effluent of constructed wetlands in a pond recirculating aquaculture system satisfy aquaculture requirements. [Method] A 150 m long, 0.5 m wide and 0.6 m deep ecological ditch was constructed on the basis of the periphyton reactor theory, to investigate the reoxygenation and deep purification effect of the ecological ditch on the effluent of constructed wetlands. [Result] Experimental 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 val- ue increased significantly by flowing though the ecological ditch （P〈0.05）. DO level in the water of ecological ditch increased linearly with the increasing length of the ecological ditch within the range of 150 m （P〈0.05）. The ecological ditch showed further removal effect on NH4＋-N, IMn and PO4^3 -P in the effluent of the constructed wetlands, with the removal rate of 19.46%, 13.38% and 31.09%, respectively. The total coliform group was also eliminated with the removal rate ranging between 12.5% and 78.13%. [Conclusion] The ecological ditch based on periphyton reactor could improve DO level and further reduce N and P contents in the effluent of the constructed wetlands, which could be used as a matching water-reuse system of constructed wetlands. Key words Water quality; Purification; Dissolved oxygen; Periphyton; Pond aquaculture展开更多
基金Supported by Earmarked Fund for Modern Agro-industry Technology Research System (CARS-46)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(Grant No.2012BAD25B05)Special Fund for Agro-scientific Research in the Public Interest(201203083)~~
文摘[Objective] This study aimed to make the effluent of constructed wetlands in a pond recirculating aquaculture system satisfy aquaculture requirements. [Method] A 150 m long, 0.5 m wide and 0.6 m deep ecological ditch was constructed on the basis of the periphyton reactor theory, to investigate the reoxygenation and deep purification effect of the ecological ditch on the effluent of constructed wetlands. [Result] Experimental 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 val- ue increased significantly by flowing though the ecological ditch （P〈0.05）. DO level in the water of ecological ditch increased linearly with the increasing length of the ecological ditch within the range of 150 m （P〈0.05）. The ecological ditch showed further removal effect on NH4＋-N, IMn and PO4^3 -P in the effluent of the constructed wetlands, with the removal rate of 19.46%, 13.38% and 31.09%, respectively. The total coliform group was also eliminated with the removal rate ranging between 12.5% and 78.13%. [Conclusion] The ecological ditch based on periphyton reactor could improve DO level and further reduce N and P contents in the effluent of the constructed wetlands, which could be used as a matching water-reuse system of constructed wetlands. Key words Water quality; Purification; Dissolved oxygen; Periphyton; Pond aquaculture
