抄録
To make clear the necessity of vegetation in constructed wetland treating wastewater, the annual removal performances of BOD, TKN, TN and TP in planted and unplanted wetland for the first three years of operation were compared using a real-scale constructed wetland. It was common for both wetlands that the removal performance was improved significantly in the second year although its magnitude was different. There was no significant difference in the annual BOD removal performances for three years of operation between planted and unplanted wetland. However, the difference was confirmed for the annual TKN removal in the third year. On the other hand, it was in the second year that the significant difference was confirmed for TN removal while it was both in the second and third year for TP. The difference in removal performances between planted and unplanted wetland was also compared using cumulative probability distributions for influent and effluent water qualities during three years of operation. The results of this study proved the overall effect of vegetation on the treatment performance in constructed wetland without plant harvesting process as well as independent treatment performance of vegetation.
