In order to investigate the feasibility of pretreating the micro-polluted Yellow River raw water by constructed wetland, an experiment was conducted using a surface flow constructed wetland with composite plant bed. T...In order to investigate the feasibility of pretreating the micro-polluted Yellow River raw water by constructed wetland, an experiment was conducted using a surface flow constructed wetland with composite plant bed. The contamination removal efficiency and their trends in the wetland treatment system were studied under different hydraulic loading rates(HLR). The contamination removal efficiencies were compared according to the seasonal change under optimum HLR. The result shows that in the same season, under different hydraulic loadings ranging from 2 to 6 m3/(m2·d) at the same period, the best HLR is 4 m3/(m2·d) in the experimental system. The average removal rates of COD, TN, ammoniacal nitrogen(NH4+-N), and TP in the constructed wetland are 38.37%, 45.97%, 39.86% and 41.69%, respectively. According to China Standard for Surface Water Resources (GB3838-2002), mean effluent of COD, TN, NH4+-N and TP can nearly reach Grade Ⅲ, GradeⅤ, GradeⅠand GradeⅠ, respectively. Furthermore, treatment efficiency of the system in summer is obvious higher than that in other seasons. The expenditure of constructing the constructed wetland with the average treating capacity of 176 m3/d and lifetime of 20 years is 17075.00 RMB. The average disposal cost is summed up to 0.17 RMB/m3, which shows that the pretreatment of the micro-polluted Yellow River raw water by constructed wetland is feasible.展开更多
As widespread wetland plants,Phragmites play a vital role in water purification and are widely utilized in constructed wetlands(accounting for 15.5%of applied wetland plants)as a natural alternative to wastewater trea...As widespread wetland plants,Phragmites play a vital role in water purification and are widely utilized in constructed wetlands(accounting for 15.5%of applied wetland plants)as a natural alternative to wastewater treatment.However,despite such common applications,current understanding of the basic composition of the Phragmites root-inhabiting microbiome and the complex functions of each member of this microbiome remains incomplete,especially regarding pollution remediation.This review summa-rizes the advances that have been made in ecological and biochemical research on the Phragmites root microbiome,including bacteria,archaea,and fungi.Based on next-generation sequencing,microbial com-munity compositions have been profiled under various environmental conditions.Furthermore,culture-based methods have helped to clarify the functions of the microbiome,such as metal iron stabilization,organic matter degradation,and nutrient element transformation.The unique community structure and functions are highly impacted by Phragmites lineages and environmental factors such as salinity.Based on the current understanding of the Phragmites root microbiome,we propose that synthetic microbial com-munities and iron–manganese plaque could be applied and intensified in constructed wetlands to help promote their water purification performance.展开更多
基金the National High Technology Research and Development Program of China(863 Program)(Grant No.2006AA06Z303).
文摘In order to investigate the feasibility of pretreating the micro-polluted Yellow River raw water by constructed wetland, an experiment was conducted using a surface flow constructed wetland with composite plant bed. The contamination removal efficiency and their trends in the wetland treatment system were studied under different hydraulic loading rates(HLR). The contamination removal efficiencies were compared according to the seasonal change under optimum HLR. The result shows that in the same season, under different hydraulic loadings ranging from 2 to 6 m3/(m2·d) at the same period, the best HLR is 4 m3/(m2·d) in the experimental system. The average removal rates of COD, TN, ammoniacal nitrogen(NH4+-N), and TP in the constructed wetland are 38.37%, 45.97%, 39.86% and 41.69%, respectively. According to China Standard for Surface Water Resources (GB3838-2002), mean effluent of COD, TN, NH4+-N and TP can nearly reach Grade Ⅲ, GradeⅤ, GradeⅠand GradeⅠ, respectively. Furthermore, treatment efficiency of the system in summer is obvious higher than that in other seasons. The expenditure of constructing the constructed wetland with the average treating capacity of 176 m3/d and lifetime of 20 years is 17075.00 RMB. The average disposal cost is summed up to 0.17 RMB/m3, which shows that the pretreatment of the micro-polluted Yellow River raw water by constructed wetland is feasible.
基金supported by the National Natural Science Foundation of China (51778603)the Chinese Academy of Sciences(QYZDY-SSW-DQC004)
文摘As widespread wetland plants,Phragmites play a vital role in water purification and are widely utilized in constructed wetlands(accounting for 15.5%of applied wetland plants)as a natural alternative to wastewater treatment.However,despite such common applications,current understanding of the basic composition of the Phragmites root-inhabiting microbiome and the complex functions of each member of this microbiome remains incomplete,especially regarding pollution remediation.This review summa-rizes the advances that have been made in ecological and biochemical research on the Phragmites root microbiome,including bacteria,archaea,and fungi.Based on next-generation sequencing,microbial com-munity compositions have been profiled under various environmental conditions.Furthermore,culture-based methods have helped to clarify the functions of the microbiome,such as metal iron stabilization,organic matter degradation,and nutrient element transformation.The unique community structure and functions are highly impacted by Phragmites lineages and environmental factors such as salinity.Based on the current understanding of the Phragmites root microbiome,we propose that synthetic microbial com-munities and iron–manganese plaque could be applied and intensified in constructed wetlands to help promote their water purification performance.
