多环芳烃污染生物修复研究进展

多环芳烃(polycyclic aromatic hydrocarbon,PAHs)是一类对环境有严重危害的持久性有机污染物。具有高生物富集性、致癌性、致毒性和难降解性,修复治理PAHs污染环境备受国内外政府及学者的关注。目前主要采用物理、化学以及生物方法对多环芳烃污染的土壤和水体进行修复。其中生物修复是一种高效、经济和生态可承受的环保技术,具有成本低、无二次污染等优点。本文从植物修复、微生物修复以及植物-微生物联合修复方面,阐述了国内外生物修复PAHs污染的最新研究进展。指出了生物修复PAHs污染环境需要进一步解决的问题,并对未来发展趋势进行了展望。     

微生物厌氧呼吸与有机污染水体沉积物修复

水体沉积物有机污染是当前全球关注的重要环境问题。微生物具有呼吸和代谢多样性,能以多种污染物作为厌氧呼吸的电子供体或受体,与周围环境中的生物和非生物因素组成代谢网络耦合有机污染物降解转化,是有机污染水体沉积物修复的重要驱动者。本文重点综述了微生物厌氧呼吸、电子传递网络及其对有机污染水体沉积物的修复机制研究进展,并对有机污染水体沉积物微生物修复理论和技术研究的问题和挑战进行了探讨。     

微生物技术治理水体重金属镉、铬污染的研究进展

近年来,随着我国工农业迅速发展,"三废"的大量排放,水体中重金属污染愈发严重,其中重金属镉、铬的污染显得尤为突出。研究者利用微生物技术开展了大量治理污水中镉、铬的研究。本文就不同种类微生物对镉、铬的修复及作用机理进行论述,以期为微生物用于实际污水中镉、铬的治理提供参考。     

植物-微生物联合对环境有机污染物降解的研究进展

环境中有机污染物的过量积累对生态系统及人类健康造成严重威胁。近年来,许多学者研究发现植物-微生物联合作用对环境中有机污染物的去除及生态系统的修复具有非常显著的效果。本文主要从植物-内生菌、植物-菌根菌以及植物-根际微生物这三个层面详细阐述植物-微生物联合降解有机污染物的研究现状,分析植物-微生物在联合降解中的作用,揭示植物-微生物联合降解的机理。但就目前而言,植物-微生物联合降解有机污染物仍存在许多问题,植物-微生物联合降解有机污染物的机理及生态学效应仍不清楚。因此,还需要进一步探讨其潜在作用机制并加强应用实践,这将有助于污染生态系统的治理,促进环境可持续发展。     

微囊藻毒素生物治理技术研究进展*

近年来,随着全球气候变暖和水体富营养化程度加深,蓝藻水华频繁暴发。微囊藻毒素是有害蓝藻产生及释放的危害最大的一类蓝藻毒素,对生态环境和公众健康造成了严重的威胁。因此,寻求有效的微囊藻毒素降解方法已成为全球科学领域的研究热点。针对微囊藻毒素生物治理技术展开综述,阐述了微囊藻毒素的产生、理化性质及生物毒性,总结了微生物、水生植物、浮游动物等自然生物降解微囊藻毒素的能力。在此基础上概述了生物滤池、人工湿地、生态浮床、膜生物膜反应器等生物治理技术对微囊藻毒素的去除效果,分析了现有微囊藻毒素生物处理方法的优势和局限性,并对今后的研究方向提出展望,为解决水环境中微囊藻毒素的污染问题提供思路。     

有机物及重金属植物修复研究进展

植物修复技术是近年来发展起来的一种非常有前途的生物治理技术 ,也是当前学术界研究的热点领域 .本文对植物修复的类型 ,植物修复土壤、水体有机污染物、重金属和某些放射性核素的过程、机理及可能影响因子作了概括和详尽讨论 ,并就国内外近年来植物修复技术在污染环境中的应用和研究成果进行了综述     

铜污染土壤的生物修复研究进展

随着工业化与农业化进程的加快,土壤重金属污染问题日益突出。铜(Cu)既是生命体生长发育的必需微量元素,也是重金属污染物之一。土壤中过量的Cu不仅会对植物产生毒害,而且能够通过食物链的富集作用,对人类健康造成严重威胁。生物修复技术作为治理重金属污染土壤的一种新型技术受到广泛关注。文中对生物修复的主要技术如植物修复、微生物修复、植物-微生物联合修复、动物修复等在治理Cu污染土壤方面的研究进展进行综述,以期为重金属污染土壤有效治理和可持续农业的发展提供理论依据。     

根系分泌物介导的根际效应及在水体生态修复中的应用潜力

文章主要以根系分泌物为核心, 综述了根系分泌物的分类、发生机理及影响因素; 围绕着植物-土壤-微生物三者的关系, 阐述了根系分泌物介导的植物与植物之间的化感作用、植物与根际微生物之间的协同作用以及植物微生物相互作用对土壤物质循环的影响。水生植物以其生境的特殊性和功能的不可替代性, 对沉积物污染物去除和水体生态修复产生显著的影响。在水体生态问题较为严峻的今天, 充分认识水生植物根系分泌物介导的根际过程将为水生植物生态学和水体生态修复领域的发展提供基础, 并为学科应用潜力的开发提供依据。     

微生物技术修复水污染的研究进展

微生物技术修复水污染以其效率高、成本低、无二次污染等特点日益受到人们的重视.从新茵株、新工艺上简述了微生物技术在修复水体有毒有机物(多环芳烃类为代表)污染、重金属污染以及富营养化治理工程中的研究成果及发展方向,提出了微生物修复研究中存在的问题并对今后的研究重点进行了展望.     

水体环境治理问题和巧用生物修复技术

近年来,我国水体环境不断恶化,大部分城市河道都受到了不同程度的污染,不仅影响了城市形象,破坏了城市景观,还对城市居民的日常生活产生了严重的影响。目前常用的水体环境治理和修复技术包括三类:物理修复技术、化学修复技术和生物修复技术。生物修复技术包括微生物修复法、人工浮岛、人工湿地等,具有工程量小、成本低、环境友好等特点,是近年来水体环境修复技术发展的主要方向。     

Potential of aquatic macrophytes and artificial floating island for removing contaminants

Eutrophication is a major environmental issue that mankind is facing today as a result of rapid development. To reduce the eutrophication problem, we are testing an innovative artificial floating islands (AFIs) approach. AFIs include aquatic plants composed of emergent and floating macrophytes. In this experimental approach, two aquatic plants were selected to compare with the control group in order to evaluate the capacity of AFIs. These two emergent macrophytes were evaluated for a 40-day timeframe to examine their ability to purify waste water. The results showed that an AFI with purple loosestrife (Lythrum salicaria Linn.) and one with yellow-flowered iris (Iris wilsonii) have a strong ability to remove nitrogen, phosphorus, and other pollutants from water bodies. The pollutant removal rates of the AFIs with purple loosestrife and yellow-flowered iris were almost over 50%. The chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) removal rates of the AFI with purple loosestrife were about 75%, 57%, 71%, respectively. At the same time, the COD, TN, and TP removal rates of the AFI with yellow-flowered iris were 60%, 49%, and 68%, respectively. AFIs with aeration are also a good way to remove pollutants. This study reveals that AFIs can be incorporated into wetlands to reduce the effects of water contamination and help strengthen wetland restoration.     

工业有机污染对小型水体沉积物真菌群落的影响分析

【背景】有机污染对水体沉积物中的微生物多样性影响极大,而目前有关污染水体沉积物中真菌多样性的研究较少。【目的】研究不同程度有机污染下水体沉积物中真菌种群的多样性特征,探究工业有机污染对真菌群落的影响。【方法】应用化学分析方法和高通量测序技术进行研究,并分析水质、沉积物成分等环境因子与沉积物真菌多样性的相关性。【结果】随着污染程度的降低,水体沉积物中真菌序列数、OTU数和Shannon多样性指数均呈上升趋势。未分类真菌、子囊菌门和担子菌门是沉积物真菌群落中的主要优势种类,主要优势属为Zopfiella、Westerdykella、Clypeosphaeria、Ilyonectria、Paracremonium、Aspergillus。真菌Shannon指数与水体溶解氧(dissolvedoxygen,DO)极显著正相关,与沉积物有机质和总磷含量显著负相关,Simpson指数与水体总氮(total nitrogen,TN)、氨氮(NH3-N)、总磷(total phosphorus,TP)显著相关。【结论】有机污染导致水体溶解氧下降和沉积物有机质增加,从而导致污染区真菌多样性显著下降。Zopfiella、Penicillium、Emericellopsis、Westerdykella、Jugulospora、Chromelosporium可能参与曝气处理区域沉积物兼氧条件下污染物的去除,Ilyonectria、Mortierella、Epicoccum可能主要参与水生生物残体分解、污染物的吸附沉降等过程。     

RNA‑seq技术在水生生物生态毒理学中的应用进展

水域是地球环境的重要组成部分,也是最易受污染的生态系统之一。水生态系统中不同营养级别的水生生物可通过摄食、接触等多种途径摄入水体中的污染物。因此,监测水域污染物对水生生物和生态系统的影响,解析污染物对不同水生生物的毒性机制,筛选敏感、有效的生物标志物对生态毒理学研究和环境风险评价具有重要意义。RNA测序（RNA sequencing,RNA?seq）技术因所需样品量少,且不需参考序列,可在整体水平上鉴定基因差异表达,成为水生生物生态毒理学研究的最佳方法之一。基于此,介绍了RNA?seq技术的基本流程与数据分析过程,对该技术在不同生态位的水生生物（如鱼类、两栖类、贝类、甲壳类等）生态毒理学中的应用展开综述,并对RNA?seq技术面临的不足、挑战及发展趋势进行探讨,以期为该技术在水生生物生态毒理学研究中的应用,尤其是水生态环境中污染物胁迫水生生物机制的阐明及污染水域生态环境恢复提供参考。     

Organic impurities in natural waters of the Tom’ basin

Analysis of gas chromatography-mass spectrometry and IR spectrometry shows that the composition of organic impurities in stream and water bodies of the Tom’ basin depends on natural and anthropogenic factors. The anthropogenic load is especially important, as the organic impurities originating from oil (paraffins, isoparaffins, naphthenes, aromatic hydrocarbons) are predominant; other pollutants of anthropogenic origin are also present (phthalates, carboxylic acids and their esters, phosphates). The composition of organic pollutants dumped into the river from each industrial zone has been analyzed both qualitatively and quantitatively.     

周丛藻类及其在水质净化中的应用

周丛藻类广泛存在于自然界水体中,具有生物量大、生态功能强、水质响应灵敏等特征.周丛藻类通过吸收代谢利用、吸附和络合等过程去除水体污染物质,用于水质净化,具有耐污能力强,N、P去除效果好,藻类细胞回收利用价值高等优点,推广应用前景广阔.近年开发的藻丛刷系统、周丛藻类 生物膜系统和周丛藻类水产养殖系统等已经成功用于畜禽水产养殖废水、生活污水处理.而周丛藻类的生存规律、对污染物浓度的生理响应机理和污染物质吸收利用的分子生物学机制仍有待进一步研究.     

A critical review of the occurrence of perfluoroalkyl acids in aqueous environments and their removal by adsorption onto carbon nanotubes

The presence of perfluoroalkyl acids (PFAAs) in aquatic environments is a cause of concern, due to their toxicity, possible ecological impact and adverse effects in man. The release of these pollutants into receiving water bodies occurs primarily through the discharge of untreated wastewater and industrial effluents. Consequently, there is a need to remediate wastewater containing these compounds before its discharge. In this review, the occurrence of PFAAs in water streams is reviewed, with the aim of providing in-depth information on the harmful effects arising through exposure to these pollutants by both man and the environment. One viable strategy for the removal of PFAAs from wastewaters is adsorption. This technique is discussed in relation to a number of conventional adsorbents and they are compared with the behaviour of a more effective adsorbent, namely, carbon nanotubes (CNTs). In particular, various functionalization strategies can increase the efficiency of CNTs for the removal of PFAAs. Sorption of PFAAs onto CNTs demonstrates good removal efficiencies and equilibrium is attained faster than with conventional adsorbents. This is attributed to the inherent properties of CNTs, such as large surface area/porosity, and the ease with which new functional groups are introduced onto the walls of the tubes. The adsorption mechanism of PFAAs is primarily enhanced through electrostatic interactions; however, other intermolecular forces, such as hydrogen bonding, hydrophobic interactions and ion-exchange, also play a role. This review aims at providing information on the occurrence and fate of PFAAs and the interactions involved in their removal from aqueous solutions by CNTs.     

Spatial distribution,size structure,and prey of Craspedacusta sowerbyi Lankester in a shallow New Zealand lake

Solar ultraviolet radiation both degrades and alters the quality of natural organic matter as well as organic pollutants in surface waters. Still, it is only recently that this indirect influence of photochemical processes on aquatic organisms (e.g. bacteria) has received attention. We experimentally studied the photochemical degradation of three PAHs; anthracene, phenanthrene and naphthalene, in water. Anthracene and phenanthrene were rapidly photodegraded (half-lives of 1 and 20.4 hours, respectively), while the photochemical half-life of naphthalene exceeded 100 hours. Hence photodegradation is most likely a less important removal mechanism for the latter compound. The influence of humic substance additions (0–25 mg C l^–1) on degradation rates was also assessed, and while photodegradation of anthracene was not affected by these additions, phenanthrene photodegradation slowed down considerably at the higher humic substance concentrations. These differential responses of anthracene and phenanthrene can at least partially be explained by differences in the spectral absorbance of the two compounds. In contrast, ionic strength did not have any appreciable effect on the estimated photodegradation rates of either compound. The influence of PAHs on growth of aquatic bacteria was assessed in dilution cultures with and without exposure to PAHs and simulated solar UV radiation. Separately, neither PAHs nor simulated solar UV radiation had any effect on bacterial growth. However, when combined, a marked inhibition of bacterial growth could be observed in water obtained from a clearwater lake. This could be due to the formation of toxic photodegradation products such as quinones (detected in our incubations) or other reactive species that affect bacteria negatively. Hence, in addition to influencing the fate and persistence of PAHs in aquatic systems, solar radiation and natural organic matter and regulate the toxicity of these compounds to indigenous micro-organisms.     

Performance improvement of raw water pretreatment process with pre-inoculation biofilm: feasibility and limiting factors

The initial formation of biofilm and the removal performance of pollutants in biological pretreatment process for polluted raw water were limited due to the oligotrophic niche in raw water. In this study, the feasibility of using pre-inoculation biofilm formed under nutrients enhanced condition for polluted raw water treatment was analyzed in nine batch reactors. Results showed that the pollutants removal performance of biofilm was improved under nutrients enhanced conditions. Ammonia oxidation rate (AOR) was exponentially increased with the increasing in NH₄ ⁺-N levels, and organic matter removal rate (ORR) was positively related to the initial total organic carbon (TOC) concentration. The biofilm formation and microbial diversity were further improved via adding more substrates, seeding river sediment and feeding effluent from a mature biofilm reactor. However, the biofilm formed under higher substrate conditions had higher half-saturation constant values (K _S) to both NH₄ ⁺-N and TOC, which decreased AOR and ORR values when it was used to treat polluted raw water. The reduction percentage of AOR and ORR showed logarithmic growth modes with the increase in K _S values. Fortunately, improvement of nutrients flux via accelerating influent replacement could enhance the start-up performance effectively and decrease the operation risk introduced by the changes in substrate affinity.     

溶解性有机质对土壤中有机污染物环境行为的影响

土壤中溶解性有机质(DOM)是生物活性和物理化学反应活性都很活跃的有机组分,主要通过疏水吸附、分配、氢键、电荷转移、共价键、范德华力等多种作用与有机污染物结合,提高溶液中有机污染物的溶解度,改变土壤中有机污染物的吸附-解吸、迁移-转化等环境行为．DOM对有机污染物的吸附-解吸、迁移-转化过程的影响有双重性：一方面,DOM与有机污染物在土壤表面的共吸附可增加土壤对有机污染物的吸附容量,促进有机污染物在土壤中的吸持;另一方面,DOM对有机污染物的增溶作用,有利于土壤中有机污染物的解吸,提高移动性．作为光敏剂,DOM能提高土壤中有机物的光解反应速率．在一定条件下,DOM也可影响土壤中有机污染物的水解过程．DOM对土壤中有机污染物环境行为的影响与DOM和有机污染物的性质及其相互作用的介质条件密切相关．