Abstract: Abstract: A constructed wetlands ecosystem was developed with a low frequent operation combined with pond facilities to circularly treat culture wastewater for the purpose of studying the performance and dynamics of nitrogen removal in constructed wetlands. The FEW-SF wetlands ecosystem used in this study consisted of a free water surface flow (FWS) wetland and a subsurface flow (SF) wetland. The whole area of FEW-SF wetlands was 582.2 m2, including three units: the slope unit, the macrophyte unit, and the reservoir unit with an area ratio of 1:2.3:1.4. Two shrimp culture ponds with an equal size were set as experimental and control ponds respectively. Each culture pond was equipped with four microvesicle aerators and water purification nets (5.25 m × 0.90 m) hung at 2 nets/m2. The experiment was conducted during a 94 day period with no water exchange and chemical use. Since the 60th day, the constructed wetlands ecosystem was operated for three times at a hydraulic loading rate (HLR) of 1.65 m/d and significantly removed TAN, TN, NO2-N by 37.9%, 26.7% (P≤0.01), and 22.7% (P≤0.05) respectively. Removal efficiencies of various nitrogen when culture wastewater was retained in the macrophytes unit for 144h showed that NO2-N, NO3-N and TN were significantly (P≤0.01) decreased at 6 h (17.5%), 18 h (25.8%), and 24 h (25.9%). The mean daily removal rate of each parameter declined with time and the removal rates of NO2-N, NO3-N and TN were 0.372-1.568 g/m2·d, 0.880-2.600 g/m2·d, 0.843-2.455 g/m2·d respectively and were higher than that of TAN. The concentrations of NO2-N, NO3-N, and TN declined with static time at an exponential function, in line with the first-order dynamics equation and the removal rate constants were 0.036 h-1, 0.029 h-1 and 0.009 h-1. The initial main component of TN in culture wastewater was TIN, and then the main component of TN was gradually converted to TON after about static 52 h.The main water quality in the experimental pond was within the acceptable range for shrimp growth or survival and blue-green algae bloom was strongly inhibited. At the end of the experiment, average adult shrimp size and yield were significantly larger or higher than that in the control pond (P≤0.01). This experiment shows that the constructed wetlands ecosystem can effectively remove nitrogen and inhibit blue-green algae growth at low frequency operation combined with pond facilities without water exchange and medicine usage during a culture period to maintain the good water quality and finally ensure a good harvest.