罗氏沼虾池塘间歇运转人工湿地调控水质效果及其生长特征

兼用塘内微泡增氧机与净水网,以间歇运转人工湿地生态系统循环处理罗氏沼虾生产性养殖废水,研究间歇运转湿地调控虾塘水质效果与虾生长特征。由表面流与水平潜流组成的复合人工湿地生态系统(582.2 m2)水力负荷1.03 m/d,含斜坡区、挺水植物区与蓄水池。养殖周期内(117 d)无换水与用药,31 d后间歇运转湿地循环处理虾塘水,NO3--N与CODMn去除率分别为66.4%、39.6%(P≤0.01),TAN显著去除(45.0%,P≤0.05),NO2--N去除率为33.3%,维持极低浓度(0.006±0.005)mg/L]。试验塘主要水化指标处于罗氏沼虾生长适宜与安全范围,蓝绿藻得以有效抑制。对照塘遭受蓝绿藻毒性作用,收获虾规格与产量(8.70 g,0.32 kg/m2)均低于试验塘(9.51~10.72 g,0.38~0.41 kg/m2)。试验建立了表征罗氏沼虾体重与体长、体重和体长分别与养殖时间的3组生长方程,可为制定罗氏沼虾养殖生产计划、调整生产措施以及预估产量提供科学依据。试验结果表明,在未用药与换水条件下,兼用塘内简易设施,间歇运转人工湿地可节省能源,有效调控虾塘水质,确保养殖成功。

The effect of regulating-controlling water quality by constructed wetlands at intermittent operation for Macrobrachium rosenbergii culture and the prawn growth characteristic

A constructed wetlands ecosystem was developed with intermittent operation combined with microvesiele aerators and water purification nets to circularly treat culture wastewater for the purpose of studying the effect of regulating-controlling water quality for Macrobrachium rosenbergii culture and the prawn growth characteristic. The FWS-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 FWS-SF wetlands was 582.2 m2, including three units： the slope unit, the macrophyte unit, and the reservoir unit. The experiment was conducted during a 117 day period with no water exchange and medicine use. Since the 31th day, the constructed wetlands ecosystem was intermittently operated at a hydraulic loading rate （HLR） of 1.03 m/d during the culture period, and significantly removed NO3 --N, CODMn, TAN by 66.4% , 39.6% （P ≤0.01 ）, and 45.0% （P≤〈0.05） respectively, the removal percentage of NO2--N was 33.3% and keep in very low concentration （0. 006 ± 0. 005 mg/L）. The main aquatic chemical parameters of experimental ponds were all maintained within a suitable and safe range for prawn growth, and blue-green algae bloom was effectively inhibited. At the end of the experiment, because of blue-green algae toxic effect, average adult prawn size and yield of the control pond （8.70 g, 0.32 kg/m2） were smaller or lower than that in the experimental pond （9.51 -10.72 g, 0.38 -0.41 kg/m2）. The study presented three groups of growth equations of the relationship between body weight and body length, body weight and culture days, body length and culture days, respectively, it can provide a scientific basis for designing the culture production plan, adjusting the production measures and estimating yield of Macrobrachium rosenbergii. This experiment shows that constructed wetlands ecosystem at intermittent operation and combined with pond simple facilities could effectively control water quality in prawn