人工湿地及其在工业废水处理中的应用

论述了人工湿地污水处理技术的机理和优点,人工湿地利用基质、植物和微生物这个复合生态系统的物理、化学和生物的三重协调作用,通过过滤,吸附、共沉淀、离子交换,植物吸收和微生物分解来实现对废水的高效净化,同时通过营养物质和水分的生物地球化学循环,促进绿色植物生长并使其增产,实现废水的资源化与无害化;人工湿地污水处理系统具有出水水质稳定,对营养物质去除能力强,基建和运行费用低,技术含量低,维护管理方便,耐冲击负荷强,适于处理间歇排放的污水和具有美学价值等优点,该技术不仅能够在发展中国家和发达国家的城市生活污水处理中广泛应用,其在工业废水处理中的应用也正在不断受到重视,根据人工湿地在工业废水处理中的研究和应用现状,指出了人工湿地处理特殊工业废水的前景及今后的研究方向。     

人工湿地微生物的研究进展

人工湿地是20世纪70年代末得到迅速发展的一种污水处理技术工程,具有投资低、运行费用低、维护技术水平低和能耗低等优点。目前已被用于处理各种类型的废水。它是由基质、植物和微生物构成的复合系统,其中,微生物在人工湿地系统净化污水过程中发挥着重要作用。从人工湿地微生物群落多样性和功能性两方面对人工湿地系统中微生物的研究进展进行了概述,进而对人工湿地微生物研究的前景进行了展望,旨在为该领域的相关研究提供资料和借鉴。     

高风险四环素抗性基因在人工湿地中分布和去除的季节变化

畜禽养殖废水是抗生素抗性基因(ARGs)的重要贮存库,环境风险不容忽视。本研究考察了夏、冬两季养猪废水中高环境风险四环素抗性基因(TRGs)在水平潜流人工湿地中的分布和去除情况,通过外源添加四环素(TC)和铜离子(Cu²⁺)探究了养猪废水中抗生素与重金属单一和复合污染对湿地出水中TRGs丰度的影响。结果表明: 养猪废水中3种高环境风险TRGs(tetM、tetO、tetW)均有检出,人工湿地可有效消减废水中的TRGs,夏、冬两季时出水中TRGs的绝对丰度较进水分别降低1.1～2.4和1.7～2.9个数量级。TRGs在湿地土壤中的丰度呈现出水端低于进水端、植物非根际低于根际、冬季低于夏季的特征。与对照相比,养猪废水中TC、Cu²⁺单一和复合污染在夏、冬两季均会导致湿地出水中TRGs相对丰度的增加。人工湿地作为一种生态处理工艺可用于控制畜禽养殖废水中的ARGs向环境中扩散。     

微生态制剂在水产养殖中的作用

微生态制剂的主要作用有 :净化水质、改善养殖水体环境 ;抑制病原微生物 ,提高机体免疫力 ;作为饲料添加剂 ,促进养殖生物生长 ;常用的微生物菌群主要有光合细菌、硝化细菌、芽孢杆菌等。综述了微生态制剂在水产养殖中的作用及常用微生物菌群。     

人工湿地氮去除关键功能微生物生态学研究进展

人工湿地是一种能有效处理水体氮素污染的生态技术,其中微生物是驱动人工湿地系统中氮素去除的重要引擎。近20年来,随着分子生物学技术的广泛应用,有关人工湿地氮去除功能微生物生态学方面研究取得了一些重要进展。以硝化-反硝化作用和厌氧氨氧化作用这两种重要的人工湿地微生物脱氮途径为主,针对氨氧化细菌/古菌、厌氧氨氧化菌和反硝化菌等关键脱氮功能微生物的研究,重点归纳总结了目前有关这几类关键功能菌群在人工湿地中的丰度、活性、多样性、分布特征与影响因素,及其对废水中氮去除的作用,并在此基础上对今后的重点研究工作提出了展望。面向未来人工湿地氮去除关键功能微生物的研究应侧重其在污水净化和温室气体减排等方面的生态功能研究,同时加强其代谢过程与机制以及不同功能菌群间的关联研究。     

北京龙形水系三种沉水植物根际及叶际微生物群落特征

水生植物及植物表面附着微生物在人工湿地水体净化过程中发挥着重要的作用。以北京奥林匹克公园龙形水系为研究对象,通过高通量测序技术,对其底泥、水体及3种沉水植物——苦草Vallisneria natans、狐尾藻Myriophyllum verticillatum、龙须眼子菜Potamogeton pectinatus——的根际及叶际微生物群落的结构及功能进行了研究。结果表明,微生物多样性从高到低分别为底泥样品、植物根际样品、植物叶际样品和水体样品,植物叶际微生物种类要显著高于水体中微生物种类。LEfSe分析结果显示不同生境富集不同的微生物类群,其中底泥主要富集厌氧微生物类群,水体及植物叶际主要富集好氧微生物类群,植物根际则两者兼具。功能预测结果显示植物叶际样品的反硝化标志基因丰度要高于根际样品及底泥和水体样品,且狐尾藻和龙须眼子菜叶际样品反硝化标志基因丰度要高于苦草叶际样品。本研究可以为人工湿地构建时对沉水植物及功能微生物的选择提供指导意义。     

水产养殖废水的危害及处理技术

目前,我国的水产养殖行业发展迅速,但养殖过程中缺乏科学的规范指导,因而会产生大量养殖废水。排放未经处理的水产养殖废水,不仅会破坏生态平衡,还会影响水产品的质量,甚至危害人们的生命健康。因此,为了解决水产养殖废水的问题,实现可持续发展,处理水产养殖废水的技术便应运而生。文章总结了物理法、生物法和物理化学法处理水产养殖废水的利弊,得知物理法和化学法具有成本花费高、再利用程度低等不足。生物法则具有周期短、危害小、花费少、可循环利用等优点,可为养殖户提供理论参考。     

好氧反硝化菌

<正>养殖水体氮素污染问题是目前困扰我国水产养殖业可持续发展的一大难题。生物脱氮技术被认为是目前最具发展前景的水体脱氮技术,其效果的优劣与所采用菌株的特性密切相关。传统反硝化细菌仅能在厌氧及低氧条件下发挥脱氮作用,与养殖水体的高溶氧环境矛盾,而好氧反硝化细菌则可在高溶氧环境中发挥脱氮作用,显著提高生物脱氮技术在养殖水体中的应用效果,实现养殖水体的绿色、零污染脱氮。因而,对好氧反硝化细菌开展高效选育方法的研究,找到可适应养殖水体水环境的微生物菌株具有重要的理论价值和经济价值。     

几种微生物制剂和微藻在水产养殖中的应用

工厂化高密度养殖,需人工大量投喂饲料,饵料残余及水产动物的排泄物溶解于水中,对养殖水体造成污染,危害养殖对象的健康生长。对鱼虾疾病用药物防治只是暂时性手段,广谱抗生素杀死或抑制了敏感细菌而保留了耐药的致病菌,破坏或干扰了水体原有的正常微生物区系的生态平衡,更增加了养殖动物感染病菌的机会,抗生素在生物体内的残留,最终会对人体产生危害。微生物应用于水产养殖来改善水体生态环境,抑制杀死病原微生物,并可作为饲料添加剂,补充营养成分,改善养殖动物胃肠道有益菌群,达到生态防治的目的,使养殖生产良性发展,取得更好的经济效益、生态效益。本文对目前国内外较为普遍应用于水产养殖的几种微生物、微藻类在水处理、防治病原微生物和病害发生方面的应用情况和发展动态进行了分析。       

不同类型人工湿地微生物群落的研究进展

微生物是人工湿地不可缺少的成员,对湿地生态系统中物质转化、能量流动起着重要作用.本文从人工湿地微生物群落的研究方法、微生物群落结构与组成、微生物群落调节作用与环境因素的关系等方面,综述了人工湿地微生物的研究进展.各种新颖的分子生物学方法已经成为研究人工湿地的微生物多样性的有力工具,其中最常见的是变性梯度凝胶电泳(DGGE)和寡核苷酸荧光探针原位杂交(FISH);人工湿地微生物群落的调节作用主要取决于湿地的水文条件、废水的特点(包括组成成分,污染物的特点和利用性)、湿地的过滤材料或土壤类型、植物和各种环境因素;不同人工湿地类型的微生物群落组成,从多到少依次是变形菌、噬纤维菌.黄杆菌菌群、放线菌和厚壁菌.如何进一步加深对氮循环相关微生物多样性的研究,提高废水中氮的去除效率依然是未来人工湿地技术需要解决的重要问题之一.     

不同接种浓度绿球藻对水产养殖废水净化的影响

通过设置绿球藻(Chlorococcum sphacosum GD)的起始接种浓度(25—400 mg/L), 研究其对水产养殖废水的处理效果及藻细胞的生长特性。研究结果表明, 起始接种浓度为100 mg/L的绿球藻藻液, 其生长特性最佳, 比生长速率最大, 倍增时间最短。随着起始接种浓度的增加, 生长速率逐渐降低, 倍增时间逐渐增加。在起始接种浓度为100 mg/L的条件下, 在5d的培养周期内, 绿球藻能够去除水产养殖废水中96.92%的COD、98.08%的氨氮、98.67%的亚硝氮、91.42%的硝氮及98.36%的总磷。低起始接种浓度(尤其是100 mg/L)有利于绿球藻的生长和污染物降解。研究初步探明了微藻起始接种浓度对水产养殖废水处理效果的影响。通过控制微藻接种浓度有望在提高污染物去除率的同时缩短培养周期并提高容积负荷, 为今后微藻用于大规模水产养殖废水的处理提供了一定的理论支持。     

植物与土壤微生物在调控生态系统养分循环中的作用

陆地生态系统的地上、地下是相互联系的。植物与土壤微生物作为陆地生态系统中的重要组成部分, 它们之间的相互作用是生态系统地上、地下结合的重要纽带。该文首先介绍了植物在养分循环中对营养元素的吸收、积累和归还等作用, 阐述了土壤微生物对养分有效性及土壤质量具有重要的作用。其次, 重点综述了植物与土壤微生物之间相互依存、相互竞争的关系。植物通过其凋落物与分泌物为土壤微生物提供营养, 土壤微生物作为分解者提供植物可吸收的营养元素, 比如共生体菌根真菌即可使植物根与土壤真菌达到互惠。然而, 植物的养分吸收与微生物的养分固持同时存在, 因而两者之间存在对养分的竞争。通过植物多样性对土壤微生物多样性的影响分析, 以及土壤微生物直接或间接作用于植物多样性和生产力的分析, 探讨了植物物种多样性与土壤微生物多样性之间的内在联系。针对当前植物与土壤微生物对养分循环的调控机制的争论, 提出植物凋落物是调节植物与土壤微生物养分循环的良好媒介, 植物与土壤微生物的共同作用对维持整个生态系统的稳定性具有重要意义。也指出了目前在陆地生态系统地上、地下研究中存在的不足和亟待解决的问题。     

Effect of an integrated mangrove-aquaculture system on aquacultural health

Mangroves are unique intertidal halophyte formations growing in sheltered tropical and subtropical coastal areas. Due to the increasing population and economic development, mangroves have faced degrada-tion and loss, which has been mainly caused by land conversion into aquaculture ponds in Asia. In the past several decades, the rapid growth of aquaculture has induced water pollution. Using mangroves for effluent treatment from coastal aquaculture ponds could be a suitable approach for wastewater treatment and healthy aquaculture development. An Integrated Mangrove-Aquaculture System (IMAS) was established to test whether the idea of a mangrove in situ treatment for aquaculture wastewater is feasible. The monocultures of three mangroves, Sonneratia caseolaris, Kandelia obo-vata, and Aegiceras corniculatum were established with area proportions of 45%, 30%, or 15%, respectively. One control pond without mangroves was also set up. The results indicated that the mangroves had different toler-abilities to long-term inundation. The aquaculture ponds had different fishery yields, considering the mangrove species and area proportions. The water quality of most of the experimental ponds was better than the control pond, except for the planted Sonneratia. It is concluded that mangroves can reduce the concentration of dissolved inorganic nitrogen and phosphate, buffer the pH value and increase the concertration of dissolved oxygen in aqua-culture water bodies effectively. It is suggested to use 15% of the Aegiceras corniculatum area to conduct in situ purification of aquaculture wastewater and to enhance aquaculture production.     

Use of a microbial sensor: a new approach to the measurement of inhibitory effects on the microbial activity of activated sludge

This paper presents a new method for the measurement of inhibitory effects in wastewater treatment plants on the basis of a continuous measurement of the microbial respiration product (CO(2)). The microbial sensor developed for this purpose consists of a small conical fluidized bed reactor connected to a cylindrical chamber that comprises part of the sample recirculation system. Activated sludge microbes are immobilized on spherical (diameter=1-2 mm) reticulated sinter glass carriers. Pure oxygen is supplied via the cylindrical chamber in order to sustain a highly dense population of microbial mass. The mean hydraulic retention time in the microbial sensor ranges between 30 and 40 min, while temperature is maintained at 30 degrees C, and pH 6.4. Carbon dioxide in the off-gas, which reflects the microbial activity, is continuously analyzed by means of an infrared analyzer. Inhibition of microbial activity (toxicity) can be determined as the mean percent reduction in carbon dioxide concentration. Several substances were tested and proved toxic to the microbes. With this microbial sensor, early detection of toxic substances becomes feasible, preventing them from entering an activated sludge unit operation.     

Effect of an integrated mangrove-aquaculture system on aquacultural health

Mangroves are unique intertidal halophyte formations growing in sheltered tropical and subtropical coastal areas. Due to the increasing population and economic development, mangroves have faced degradation and loss, which has been mainly caused by land conversion into aquaculture ponds in Asia. In the past several decades, the rapid growth of aquaculture has induced water pollution. Using mangroves for effluent treatment from coastal aquaculture ponds could be a suitable approach for wastewater treatment and healthy aquaculture development. An Integrated Mangrove-Aquaculture System (IMAS) was established to test whether the idea of a mangrove in situ treatment for aquaculture wastewater is feasible. The monocultures of three mangroves, Sonneratia caseolaris, Kandelia obovata, and Aegiceras corniculatum were established with area proportions of 45%, 30%, or 15%, respectively. One control pond without mangroves was also set up. The results indicated that the mangroves had different tolerabilities to long-term inundation. The aquaculture ponds had different fishery yields, considering the mangrove species and area proportions. The water quality of most of the experimental ponds was better than the control pond, except for the planted Sonneratia. It is concluded that mangroves can reduce the concentration of dissolved inorganic nitrogen and phosphate, buffer the pH value and increase the concertration of dissolved oxygen in aquaculture water bodies effectively. It is suggested to use 15% of the Aegiceras corniculatum area to conduct in situ purification of aquaculture wastewater and to enhance aquaculture production.     

基于微藻的水产养殖废水处理技术研究进展

摘要：利用微藻处理水产养殖废水是一项污水资源化生物技术。近年来,国内外开展了大量有关藻类培养和废水处理的研究,发展了藻类处理技术,包括藻类塘、活性藻、固定化藻类、光生物反应器。本文综述了微藻净化水产养殖废?水的原理、研究成果及应用实例,并对今后的研究方向提出了建议。     

Recycling of aquaculture wastewater using charcoal based constructed wetlands

Abstract

The competitive demand for water makes it a scarce resource for agricultural use. This necessitates wastewater reuse for irrigation and any other agricultural purpose, especially in developing countries where treatment of wastewaters is not a priority. The aim of this study was to evaluate the performance of a charcoal-based constructed wetland (CBCW) in treating aquaculture wastewater. Aquaculture wastewater from a Research Fishpond Farm was treated in a CBCW planted with Sacciolepsis africana and Commelina cyannae for 5?days retention time. Raw wastewater and the treated wastewater from the constructed wetland (CW) was sampled and the physicochemical parameters determined. The performance of the CW in treating aquaculture wastewater was conducted. The result showed that the CBCW was capable of removing 50% TSS, 88% COD, 93% BOD_5, and 100% nitrate nitrogen. The pH and DO of the wastewater before treatment and after treatment ranged from 6.68 to 6.91 and 4.13 to 6.30?mg/l, respectively. Thus, CWs have great potential for the treatment of aquaculture wastewater and prevention of environmental degradation through wastewater treatment, thereby solving the problem of water scarcity for agriculture for optimum food production.     

光合细菌在水污染治理中的研究进展

光合细菌以其无毒、繁殖快、适应能力强、易人工培养等优点而在环境治理中受到重视。国内外对光合细菌的研究主要集中在水产养殖业(如净化水质,作饵料添加剂等)和生活及工业重污染水处理中的作用,关于光合细菌在景观微污染水体治理方面的作用研究较少。课题组研究发现光合细菌中的沼泽红假单胞菌对西南大学景观水中氨氮的去除率高达95%,暗示光合细菌能有效治理景观水污染。综述了光合细菌的分类、脱氮除磷原理以及目前光合细菌在治理有机废水、重金属废水和养殖污水方面的应用,并展望了光合细菌在处理景观微污染水体方面的应用前景,以期为进一步研究光合细菌在景观水治理中的作用提供参考。     

Status of pathogens,antibiotic resistance genes and antibiotic residues in wastewater treatment systems

Pathogens are becoming nearly untreatable due to the rise in gaining new resistance against standard antibiotics. Coexistence of microbial pathogens, antibiotics and antibiotic resistant genes (ARGs) in wastewater treatment plants (WWTP) provide favourable conditions for the development of new antibiotic resistant bacteria (ARB); facilitate horizontal gene transfer among pathogens and may also serve as a hotspot for the spread of ARB and genes into the environment. In this study, the current status of wastewater treatment systems in the removal of pathogens, ARGs, and antibiotic residues are discussed. WWTP are efficient in removing pathogens and antibiotic residues to a greater extend during secondary and tertiary treatment processes. Recent studies, however, have shown high variations in the presence of pathogens including ARB as well as antibiotic resistance genes (ARG) in the final effluent. Prolonged sludge retention time (SRT) and hydraulic retention time (HRT) during secondary treatment will facilitate antibiotic removal by adsorption and biodegradation. However, the above conditions can also lead to the enhancement of antibiotic resistance process in microbes. Therefore, optimum conditions for the operation of conventional WWTP for the efficient removal of antibiotics are yet to be established. The removal of antibiotic residues can be accelerated by combining conventional activated sludge (CAS) process with an additional treatment technology involving dosing with ozone. The advanced biological treatment method using membrane bioreactors (MBR) in combination with coagulation reportedly has the best ARG removal efficiency, and removes both ARB and extracellular ARGs. While studies have predicted the fate for ARGs in wastewater treatment plants, the mechanisms of ARGs acquisition remains to be conclusively established. Thus, strategies to investigate the underlying mechanism of acquisition of ARGs within the WWTP are also provided in this review.     

人工湿地处理造纸废水后细菌群落结构变化

人工湿地通过模拟自然湿地的生态系统,能够实现污染物的去除,是一种高效经济的污水处理手段,但是对人工湿地处理后污水中细菌群落的研究较少。采集了造纸厂排污口和人工湿地出水口的水样,检测了溶解氧、pH值和盐度等水质指标,对主要污染物的含量进行了测定和分析,并利用DGGE技术对细菌群落的变化进行了研究。结果表明:(1)造纸污水经人工湿地处理后水质有明显提高;(2)人工湿地处理后细菌群落结构发生变化,优势菌由γ变形菌和衣原体变为α变形菌,而且微生物多样性指数Shannon-Wiener's降低;(3)人工湿地处理前污水中存在着大量致病微生物和降解微生物,处理后以环境友好的固氮菌和少量致病菌为主。研究结果揭示了人工湿地不仅可以去除造纸废水中的污染物,改善水质而且可以大大减少向环境中排放的致病微生物,防止由致病微生物引起的生态灾难的发生,为将来人工湿地应用于工业污水处理和微生物生态安全评估提供有效可靠的依据。