三种水（湿）生植物对浑河水质氮去除能力研究

根据浑河实际水体富营养化状态,以黄菖蒲、菖蒲和溪荪鸢尾三种常见水生植物为材料,通过室内水培实验研究了三种植物对不同程度富营养化水体中氮的去除能力。结果表明：3种植物对初始浓度为60mg/l和15mg/l的总氮及30mg/l和7.5mg/l的氨氮都有较好的去除效果。实验结束时,黄菖蒲、菖蒲和溪荪鸢尾在高氮和低氮处理中的TN(总氮)去除率分别为71.17%、 95.03%,46.69%、78.31%和51.98%、80.34%;黄菖蒲、菖蒲和溪荪鸢尾在两种处理中的NH4+-N（氨氮）去除率分别为93.33%、69.37%,58.61%、97.33%和73.03%、84.00%。三种植物对低浓度处理中的总氮的去除效果更好,其中,黄菖蒲对两种处理的总氮和高浓度氨氮的去除率最高;黄菖蒲和菖蒲分别对两种处理中的氨氮去除率最高。三种植物在两周内都可以达到较好的去除效果,黄菖蒲和溪荪鸢尾两种植物相对无植物系统的空白对照的营养去除增效均在17到23天达到最大值。     

End-of-pipe single-sludge denitrification in pilot-scale recirculating aquaculture systems

A step toward environmental sustainability of recirculat aquaculture systems (RAS) is implementation of single-sludge denitrification, a process eliminating nitrate from the aqueous environment while reducing the organic matter discharge simultaneously. Two 1700 L pilot-scale RAS systems each with a 85 L denitrification (DN) reactor treating discharged water and hydrolyzed solid waste were setup to test the kinetics of nitrate and COD removal. Nitrate removal and COD reduction efficiency was measured at two different DN-reactor sludge ages (high θ_X: 33–42 days and low θ_X: 17–23 days). Nitrate and total N (NO₃⁻ + NO₂⁻ + NH₄⁺) removal of the treated effluent water ranged from 73–99% and 60–95% during the periods, respectively, corresponding to an overall maximum RAS nitrate removal of approximately 75%. The specific nitrate removal rate increased from 17 to 23 mg NO₃⁻-N (g TVS d)⁻¹ and the maximal potential DN rate (measured at laboratory ideal conditions) increased correspondingly from 64–68 mg NO₃⁻-N (g TVS d)⁻¹ to 247–294 mg NO₃⁻-N (g TVS d)⁻¹ at high and low θ_X, respectively. Quantification of denitrifiers in the DN-reactors by qPCR showed only minor differences upon the altered sludge removal practice. The hydrolysis unit improved the biodegradability of the solid waste by increasing volatile fatty acid COD content 74–76%. COD reductions in the DN-reactors were 64–70%. In conclusion, this study showed that single-sludge denitrification was a feasible way to reduce nitrate discharge from RAS, and higher DN rates were induced at lower sludge age/increased sludge removal regime. Improved control and optimization of reactor DN-activity may be achieved by further modifying reactor design and management scheme as indicated by the variation in and between the two DN-reactors.     

热带芽孢杆菌的筛选及对人工废水效果研究

自海南热带海水养殖系统的底泥中筛选得到1株对人工废水净化效果明显的菌株L S‐1305,通过对菌落形态、16S rDNA、生理生化试验,鉴定该菌株为弯曲芽孢杆菌。研究了弯曲芽孢杆菌LS‐1305在人工废水中的生长特性及对凡纳滨对虾的安全性试验,并将密度为（2．5±0．3）×105 cf u／m L的弯曲芽孢杆菌L S‐1305活菌接种至化学需氧量、氨氮、亚硝酸盐初始质量浓度分别为（721．5±1．8） mg／L、（67．33±0．58） mg／L、68．56±2．08） mg／L的人工废水中,不间断充无菌空气培养48 h。最终建立了该菌株在人工废水中随时间的生长关系。试验结果表明,该菌株对凡纳滨对虾安全,该菌株对人工废水的化学需氧量、氨氮、亚硝酸盐的去除率分别为91．61％、86．21％、87．22％。弯曲芽孢杆菌L S‐1305具有显著改良海水养殖水体的潜在应用前景,为今后开发适合海南地区海水养殖环境的热带芽孢杆菌微生物制剂奠定了重要的基础。     

蛋白水解肽-Fe2+配合物对克氏原螯虾体内Cd2+的脱除效果

为探讨克氏原螯虾体内重金属Cd²⁺残留的脱除方法,采用基础饲料中添加制备的蛋白水解肽-Fe²⁺配合物(TPH-Fe²⁺)进行饲喂,检测螯虾不同组织器官中Cd²⁺含量变化情况。结果显示,染毒后螯虾不同器官中Cd²⁺富集量依次为内脏团>肠>鳃>腹部肌肉>螯足肌肉,且在0~12 d自然净化过程中,无显著性下降趋势。添加400、800和1 200 mg/kg TPH-Fe²⁺饲喂螯虾,内脏团、鳃、肠及腹部肌肉中Cd²⁺含量均有不同程度下降;饲喂12 d后,螯虾不同器官中Cd²⁺脱除率为肠>内脏团>鳃>腹部肌肉,脱除率分别为40.60%、36.13%、33.36%和10.15%;TPH-Fe²⁺对螯虾螯足肌肉中Cd²⁺含量无显著性影响。研究表明,蛋白水解肽-Fe²⁺配合物能有效脱除螯虾体内Cd²⁺残留,可作为一种螯虾养殖饲料添加剂在基础饲料中加以应用。     

Constructed wetlands for treatment of harvest effluents from grow‐out ponds of the Amazon river prawn

Effluent discharges from aquaculture can reduce water quality in receiving water bodies and that strategies or practices to reduce this are necessary. One possibility is to reduce, or eliminate, water renewal in grow‐out ponds. In this study, we eliminated water renewal in grow‐out ponds associated with the culture of 40 individuals m^?2 of Amazon river prawn (Macrobrachium amazonicum). At the end of the culture period it was, however, necessary to drain the pond to harvest the prawns. An experiment was performed in triplicate, in which the water supply characteristics and harvest water characteristics of ponds were evaluated. To reduce these concentrations of total N and P, an aquatic macrophyte (Eichhornia crassipes, water hyacinth) treatment system (CWs) was adopted. The water characteristics in the CWs were evaluated after 1, 3, 7, 14 and 21 days. The water supply of ponds presented the average concentrations of 0.67 ± 0.32 mg L^?1 and 17.4 ± 14.7 μg L^?1 of total‐N and total‐P respectively. The harvest effluent of ponds had elevated concentrations of different forms of nitrogen (4.44 mg L^?1 of total‐N) and phosphorous (100.9 μg L^?1 of total‐P). After 1 day of the experiment we found the following reductions in key nutrients in treatment system containing E. crassipes: 90%, 78% and 45% reductions in the concentrations of particulate matter, orthophosphates and nitrates respectively. We noted that after 3 days the nitrates had been reduced by 53%. We concluded that 3 days of this treatment was sufficient for the removal of the additional nutrients that had accumulated in the Amazon river prawn ponds.     

酵母菌处理皂素生产废水的研究

经过富集培养和逐级驯化,从4种酵母菌株中筛选出对皂素废水降解性能较好的产朊假丝酵母;用单因素和正交试验确定产朊假丝酵母对皂素生产废水进行好氧处理的工艺条件.结果表明:当CODCr为24 648.36 mg/L的皂素废水,按m(CODCr)∶m(N)∶m(P)=200∶5∶1 的配比补充尿素和KH2PO4后,在30℃、接种量10%、pH 4.5、处理时间72 h、摇床转速146 r/min的条件下,产朊假丝酵母对废水CODCr的去除率可达86.16 %,处理液中细胞干质量可达20.80 g/L.与传统的厌氧-好氧活性污泥处理工艺比较,该工艺操作简单,对皂素生产废水的CODCr耐受负荷提高1～2倍.     

不同水生植物－微生物系统去除水体氮磷能力研究

目前,中国湖泊水体的富营养化环境现状令人堪忧。如何有效利用更多具有经济价值的水生植物—微生物系统去除氮、磷（特别是氮）具有非常重要的意义。通过对不同总氮（总磷一定）浓度下香根草、水葫芦、水芹等水生植物—微生物系统培养水质、根际细菌总数及植物体氮、磷含量进行监测,来分析其水质动态变化规律,以及水质参数、根际细菌总数及水生植物之间的相关关系;揭示水生植物—微生物系统中水生植物的吸收作用和根际微生物系统对净化水质的作用。试验分析得出：3种水生植物去除营养盐氮、磷的能力各有不同,在所设置的3个总氮（TN）浓度下,各有一种植物能够达到最好的处理效果,且能较好地促进根际细菌的生长。比较而言,水芹系统对高浓度氮的吸收能力强,水葫芦系统对高浓度磷的吸收能力强。     

Comparison of Dissolved Oxygen Distribution and Nitrogen Removal Effect in Wetlands with Different Structures

The dissolved oxygen distribution and nitrogen removal effect in different structures of wetlands were investigated by two groups of comparison experiments (vertical flow with horizontal flow; single stage with three stage horizontal flow). It was found that the different hydraulic flow patterns in different structures of wetlands would result in different oxygen distribution and nitrogen removal effect. The special structure design and hydraulic flow pattern of vertical flow wetland were favorable to its dissolved oxygen distribution, which could increase 0.17 mg/L in local area than that in horizontal flow wetland. The nitrogen removal effect of vertical flow wetland was better than that of horizontal flow wetland in the same operation conditions. The removal efficiency of NH+4-N and TN could increase 9% and 5% respectively in vertical flow wetland than that in horizontal flow wetland. Because of reaeration in contacting channels of three stage wetland, the removal efficiency of NH+4-N and TN reached 66% and 71% respectively, which improved 8% and 5% respectively than that of single stage wetland. In addition, three stage wetland could keep higher nitrogen removal effect even in low operation water level, and the range of its best hydraulic retention time(HRT) was extended.     

牙鲆养殖循环系统中3种硝化作用滤器性能的比较

通过测定牙鲆Paralichthys olivaceus养殖循环水中总氨氮、亚硝酸态氮和硝酸态氮的含量,了解以塑料环、火山石和牡蛎壳为载体的3种硝化滤器生物膜的熟化情况;调节循环水流量,使硝化滤器水力停留时间分别为5、15、20、30、60min,比较氨氮去除率,得到实验条件下3种载体硝化滤器的最佳水力停留时间,并在此条件下,投加NH4Cl,使循环养殖水中总氨氮浓度分别为1、3、5mgCL,测定水中总氨氮随时间的变化,研究氨氮去除动力学规律,计算硝化滤器的去除效率。结果表明：附着于3种载体上生物膜的熟化时间约为25d;塑料环上异养菌和硝化菌数量均为最高,氧化还原反应最活跃,火山石次之,牡蛎壳最低;3种载体硝化滤器的最佳水力停留时间为20～30min。氨氮负载为1mg／L时,12h内氨氮去除为0级反应;氨氮负载分别为3mg／L和5mg／L条件下,24h内氨氮去除为0级反应。氨氮负载越大,氨氮去除速率就越大。在氨氮负载为1、3、5mg／L时,5种载体的氨氮去除效率分别为17．5l～16．39、36．39～33．04、58．96—53．25g／（m^3·d）。     

铅污染土壤的动电修复研究

通过不同修复时间和不同含水率试验,分别考察了动电修复技术在不同修复时间和不同含水率情况下对铅污染土壤的修复效果,试验过程中监测两极电极池中的pH值以及土样中电流的变化;试验结束后,测定铅在土壤中的迁移分布和土壤的含水率,并计算了每组试验中铅的去除率.结果表明:修复时间增加,污染物的去除率也相应提高,并最终趋于一个极值;含水率对去除率也有重要影响,含水率越大修复效果越显著.并对动电技术的研究发展进行了展望.