微核技术及其在监测水质污染中的应用

微核技术作为染色体损伤的快速检测方法,近年来就获得广泛应用,紫露草微核技术,蚕豆根尖细胞微核技术应用于水质污染监测取得实质性进展,具有良好的指示作用。     

浊漳河水体污染物对蚕豆根尖细胞的遗传毒性研究

运用蚕豆根尖细胞微核试验技术对浊漳河南段6个代表性样点水体中有机污染物的遗传毒性进行了研究,为浊漳河流域水体污染状况的有效监测提供理论依据.结果显示:(1)浊漳河南段各监测断面的水体有机污染物对蚕豆根尖细胞均产生了不同程度的损伤,表现出细胞微核、断片、染色体桥等多种异常形态,严重时导致细胞坏死和细胞凋亡.(2)6个样点水样处理的蚕豆根尖细胞微核率在21.47‰～64.77‰,极显著高于对照组(P<0.01).(3)各样点水样对蚕豆根尖细胞的遗传损伤程度依次为:王桥>店上>漳泽水库>北寨>黄碾>五阳;在有丝分裂后期,蚕豆根尖中异常细胞最高达70%,且异常细胞比率有随着污染程度增大而升高的趋势.研究表明,蚕豆根尖细胞微核是水质毒理检测的有效指标,其细胞有丝分裂后期异常细胞比率也可作为水质毒理检测的观察指标.     

蚕豆微核技术监测有机废水的遗传毒性

利用蚕豆根尖细胞微核技术研究有机废水对蚕豆根尖细胞的遗传损伤效应。结果表明:不同稀释梯度的实验室废水对蚕豆根尖细胞的有丝分裂指数、微核千分率及污染指数影响不同,并存在一定的差异。     

重金属对蚕豆的细胞遗传学毒理作用和对蚕豆根尖微核技术的探讨

Ｐｂ２＋ 、Ｃｄ２＋ 和Ｈｇ２＋ 显著地缩短蚕豆（Ｖｉｃｉａ ｆａｂａ Ｌ．）根尖细胞分裂的持续时间,延长细胞间期的时间间隔,在总体上延长了细胞分裂周期;除Ｈｇ２＋ 随浓度升高一直表现为对有丝分裂抑制外,在Ｐｂ２＋ 、Ｃｄ２＋ 和Ｚｎ２＋ 浓度分别小于１．０、０．０１、１０．０ ｐｐｍ 时,细胞有丝分裂指数随处理浓度升高而上升,当超出上述浓度时则随浓度升高而下降;微核率（ＭＣＮＦ）在Ｐｂ２＋ 、Ｃｄ２＋ 、Ｈｇ２＋ 和Ｚｎ２＋ 的浓度分别小于１．０、５．０、０．５０、１００．０ ｐｐｍ 时,染色体畸变率（ＣＡＦ）在Ｐｂ２＋ 、Ｃｄ２＋ 、Ｈｇ２＋ 和Ｚｎ２＋ 的浓度分别小于５．０、５．０、０．５０、１００．０ ｐｐｍ 时,这两参数随处理浓度的升高而增大;超过上述浓度后,则随处理浓度升高而下降。Ｍｎ２＋ 对各项参数无显著影响。对蚕豆根尖细胞遗传学毒性顺序为Ｈｇ２＋ ＞ Ｃｄ２＋ ＞ Ｐｂ２＋ ＞ Ｚｎ２＋ ＞ Ｍｎ２＋ 。经综合分析,３ 个参数在不同剂量范围下相关性程度有很大的差异。认为蚕豆根尖微核技术检测危险化学品和监测环境污染时取得可靠结果的条件是：受检物质在检测条件下不严重抑制细胞分裂和ＣＡＦ和ＭＣＮＦ呈正相关     

应用大蒜根尖微核技术检测水质污染的初步研究

植物微核技术的出现是近年来环境生物监测领域的重要进展之一。根据操作原理,可以把目前采用的植物微核技术分为利用减数分裂形成微核的四分体微核技术和利用有丝分裂形成微核的根尖微核技术二大类。前者如目前正在国内推广的紫露草微核技术,而根尖微核技术应用最多的是蚕豆微核技术,该技术具有经济、简便、实验周期短、易于在受控条件下进行试验以及可以确切反映出某些因素对遗传物     

利用闪蚕豆根尖细胞诱变法监测铲河西安河段污染的研究

早在兰十年代,国外学者就发现在射线作 用下引起的染色体畸变E17、七十年代以来,广 泛利用染色体畸变来检验射线和化学药剂的致 突变性ue.is坛目前,在国外已利用染色体畸变 来监测环境污染,美国环保局已把有关项目作 为监测环境污染的指标。．0 在国内,利用动、 植物在环境诱变物作用下引起染色体畸变、姊 妹染色单体交换、间期微核增加这些效应来监 测环境污染进行过探索〔3'-91。以蚕豆为材料, Francesca Degrassi建立了诱变剂检测系统us] 国内也有以此为手段进行污染监测的报道 n0,11]。我们利用蚕豆根尖细胞染色体畸变和微 核方法对流经西安东郊工业区的铲河水污染进 行了对比研究,结果如下。     

铅、镉及其复合污染对蚕豆根尖细胞的诱变效应

应用蚕豆根尖微核技术研究了Cd(1mgL^-1～25mgL^-1)、Pb(1mgL^-1～25mgL^-1)及其复合污染对根尖细胞的毒害作用,分析了重金属及复合重金属污染对蚕豆根尖细胞有丝分裂和微核及染色体畸变的影响。结果表明：Cd、Pb及其复合处理对蚕豆根尖细胞有丝分裂及染色体行为存在不同程度的影响。具体表现为：低浓度促进细胞分裂,高浓度则抑制细胞分裂;对染色体畸变的影响表现为：当浓度为1．0mgL^-1时Cd即产生显著效应,而Pb浓度达10．0mgL^-1时,表现出稳定的,强度较大的诱变效应,且随浓度的增加毒害增强。Cd、Pb间存在交互作用,Cd达低浓度时与Pb的交互作用明显而高浓度则不明显,且Cd、Pb间存在部分拮抗作用。     

用微核试验研究小枣的抗突变作用

目的:应用微核试验(Micronucleus test,MCNT)技术研究小枣汁对环磷酰胺(CP)的抗突变作用的影响.方法:使用蚕豆根尖细胞微核技术进行微核率检测.结果:结果表明,不同浓度的小枣汁对环磷酰胺诱发的蚕豆根尖细胞微核有明显的抑制作用,1号-阳性和阴性对照试验组的微核率分别为52‰、30‰、26‰、16‰、10‰、9‰、70‰、7‰,小枣汁使CP诱发的微核率从52.0±5.3‰降低至9.7±2.5(P<0.001).结论:说明小枣汁对CP诱发的遗传损伤具有明显的修复、保护以及抗突变作用.     

端粒生物学与细胞衰老

1　端粒生物学1.1　端粒的提出早在 50多年前 ,ＭｃＣｌｉｎｔｏｃｋ[1] 和Ｍｕｌｌｅｒ[2 ] 就分别在玉米和果蝇中发现损伤断裂后的染色体末端之间极易发生连接 ,从而形成各种类型的染色体畸变 ,如未端融和形成环状体或形成双着丝点染色体 (ｄｉ ｃｅｎｔｒｉｃｃｈｒｏｍｏｓｏｍｅ)。但是染色体的天然末端似乎从来不与染色体断裂产生的那种末端连接。天然末端之间也不结合 ,它象一顶“帽子”那样维持着染色体末端的稳定。于是Ｍｕｌｌｅｒ提出 ,位于染色体两端的片段在细胞里具有重要的作用 ,并命名它为端粒(Ｔｅｌｏｍｅｒｅ) [3～ 6 ] …     

氯苯胁迫对蚕豆幼苗生长和细胞分裂的影响

研究了1,2,4-三氯苯(TCB)对蚕豆幼苗生长、根尖细胞分裂及染色体畸变的影响．结果表明,随TCB浓度增加和处理时间延长,蚕豆幼苗根长的生长及根尖细胞有丝分裂指数降低甚至停止．TCB诱发蚕豆根尖细胞有丝分裂过程中染色体数目畸变和结构畸变．50-100μg.g^-1TCB胁迫12-24h,蚕豆根尖染色体的主要损伤形式为c-有丝分裂、染色体桥和不均匀排列,其出现百分率达1．0％--10.3％．300μg.g^-1TCB胁迫12-96h,蚕豆根尖细胞中染色体粘连(S)、S+染色体断裂(S+B)、S+染色体环(S+R)、S+染色体不均匀排列(S+A)及S+染色体桥(S+Be)出现的百分率达47．9％--88.9％,各种类型染色体断裂出现的百分率仅为18．1％--29．6％,说明蚕豆根尖细胞染色体畸变分析可作为TCB土壤污染监测的敏感生物监测指标．     

西安城市河流浮游植物群落结构及其与环境因子的关系

为探究西安市城市河流浮游植物群落结构特征及其与环境因子的关系,分别于2020年10月和2021年6月对灞河、浐河、沣河及黑河共计24个采样点进行了浮游植物群落组成、细胞密度和生物量的调查研究,并利用冗余分析(RDA)研究环境因子对浮游植物群落结构的影响。调查结果显示,枯水期共鉴定出浮游植物6门115种,主要包括蓝藻门(11.30%)、硅藻门(54.78%)及绿藻门(26.96%),浮游植物细胞密度均值为(3.36±3.50)×106 cells/L,生物量均值为(1.79±3.59) mg/L。丰水期共鉴定出浮游植物7门168种,主要包括蓝藻门(7.74%)、硅藻门(51.79%)及绿藻门(29.76%),浮游植物细胞密度均值为(9.17±9.73)×10⁶ cells/L,生物量均值为(6.54±11.57) mg/L。与枯水期相比,丰水期在物种数量、细胞密度和生物量都大于枯水期。聚类分析结果表明,西安城市河流大部分采样点之间浮游植物群落结构及水环境状况具有相似性,而人类活动可能是导致其余点位具有空间差异性的主要原因。冗余分析(RNA)结果表明影响西安市城市河流...     

海河流域河流生境功能识别及区域差异

城市群快速发展严重影响着区域水生态系统的完整性,大尺度流域的河流生境功能辨识和分析尚缺乏系统研究。以海河流域为例,根据河段蜿蜒度、河段比降、断流风险、盐度等4个指标,构建了河流生境功能的分类指标体系。通过多源空间数据和人工判读,划分了6254条河段,在此基础上将河流生境类型划分为15类。通过52个监测样点的鱼类调查数据,分析了不同河流生境的水生生物特征差异,揭示了鱼类多样性高的区域多位于河流比降大、断流风险低的区域,而河流蜿蜒度对于鱼类多样性影响较小。根据京津冀13个地级市的河流生境差异,提出京津冀城市群的生态安全构建需要充分考虑河流生境的空间异质性,并制定融合城市发展目标、水资源利用需求和河流生境功能的综合指标体系。     

英德西南旅游区水源河流水质与浮游生物群落特征

通过野外采样及实验室分析,调查了英德市西南旅游区水源河流上、中、下游的水质状况及浮游生物的多样性。结果表明,(1)英德市西南旅游区上、中、下游河段亚硝酸盐、氨、硝酸盐、总氮、镉、铅、铬、镍、铜、锌的含量低于国家标准,铝、钙、钴、铁、钼、硒的含量超过国家标准,而总磷、砷、镁、锰的含量在部份区段已超过国家标准;(2)浮游动物种类的个体数在整条河中以桡足类最多,上游通天岩中浮游动物个体数最多,下游碧落湖浮游动物多样性最低;此次调查总共发现68种浮游植物,其中主要集中在下游碧落湖,在中游碧落洞绿藻、蓝藻、硅藻总个体数最低,上游通天岩绿藻及甲藻总个体数最多,而下游碧落湖的蓝藻和硅藻的总个体数最多;(3)总氮、总磷、铅、钙、浮游动物Shannon-Weaver指数与浮游植物Shannon-Weaver指数从上游向下游增加,而锰与镍含量则成相反趋势。文中探讨了水中元素之间、元素与生物之间、浮游动植物之间的相互关系。本文对风景区水源的生态环境的研究风景区旅游资源开发与管理提供参考。     

Optimal Design of River Monitoring Network in Taizihe River by Matter Element Analysis

The objective of this study is to optimize the river monitoring network in Taizihe River, Northeast China. The situation of the network and water characteristics were studied in this work. During this study, water samples were collected once a month during January 2009 - December 2010 from seventeen sites. Futhermore, the 16 monitoring indexes were analyzed in the field and laboratory. The pH value of surface water sample was found to be in the range of 6.83 to 9.31, and the average concentrations of NH₄⁺-N, chemical oxygen demand (COD), volatile phenol and total phosphorus (TP) were found decreasing significantly. The water quality of the river has been improved from 2009 to 2010. Through the calculation of the data availability and the correlation between adjacent sections, it was found that the present monitoring network was inefficient as well as the optimization was indispensable. In order to improve the situation, the matter element analysis and gravity distance were applied in the optimization of river monitoring network, which were proved to be a useful method to optimize river quality monitoring network. The amount of monitoring sections were cut from 17 to 13 for the monitoring network was more cost-effective after being optimized. The results of this study could be used in developing effective management strategies to improve the environmental quality of Taizihe River. Also, the results show that the proposed model can be effectively used for the optimal design of monitoring networks in river systems.     

流溪河水质的动态特征

流溪河是广州市的一条重要河流,广州市60%的供水都来自于该河。为探讨流溪河水质的动态特征,沿河设立7个监测断面,于2003年1～12月,每月进行一次采样,对主要水质参数进行了分析。结果表明,上游良口断面全年的水质状况明显好于下游的南岗断面。除pH值外,全年南岗断面的溶解氧、高锰酸盐指数、BOD₅、氨氮和总磷均不同程度地超二类水标准,其中以溶解氧超标最为严重,最高值仅为4.94mg·L^-1。污染源分布较多的河段,其枯水期的水质要较丰水期差。从良口断面到南岗断面,pH值和溶解氧呈下降趋势,高锰酸盐指数、BOD₅、氨氮和总磷呈上升趋势,表明流溪河下游水质较差,有机污染较严重。     

非O-I群弧菌的繁殖生态学研究

作者等于1964—1966年和1978—1984年,应用水中弧菌的常规试验分离鉴定法,对非O-I群弧茵在芜湖地区自然水系中的分布进行了调查。结果看到,非O-I群弧菌在河流、湖泊和沟塘中广泛存在。同时发现在捕获得黑斑泥鳅231条中检出有9条胆囊里生存有大量非O-I群弧菌(自然阳性率为3.9％,可信限为1—6％),泥鳅胆囊里生存的非O-I群弧菌数平均为149,500(63,000—236,000)/毫升胆汁。 相继,作者等将非O-I群弧菌加入缸水中(每毫升缸水中含弧菌约100个)喂养泥鳅,进行了实验感染试验。在喂养的鱼种中有黑斑泥鳅和鲫鱼,在自然气温25.5—29℃下,饲养3—4周。然后,采用无菌术解剖鱼类摘取胆囊,收集胆汁用生理盐水稀释后进行弧菌培养和鉴定计数。结果,在喂养试验的黑斑泥鳅91条中,检出有23条胆囊里生存有大量非O-I群弧菌(喂养试验阳性率为25.2％,可信限为16—34％),泥鳅胆囊里生存的弧菌数平均为146,000(73,000—219,000)/毫升胆汁。可看出,泥鳅胆囊里生存的弧茁数比喂养时加入缸水中的弧菌数约高700—2000倍。但鲫鱼胆囊里未检出弧菌。由此看来,非O—Ⅰ群弧菌的繁殖生态学与水生动物有关,黑斑泥鳅可能是其中之一。作者等倾向相信非O-I群弧菌侵入泥鳅体内进入胆囊栖居繁殖,黑斑泥鳅有成为弧菌属菌群贮菌寄主和弧菌性腹泻传染源的可能性。     

Genetoxicity of water samples from the scenic Lijang river in the Guilin area, China, evaluated by Tradescantia bioassays.

The Lijang river which passes through the Guilin mountains, and Guilin city is a world renowned scenic spot on the southwest border of China. The river and its tributaries receive water from the mountain tops and springs underground. The river water was clean two decades ago before the development of industrial establishments and extra heavy tourism. Deforestation over the mountain tops on the upper stream and its tributaries in the last decades has created serious erosion and increased sedimentation in the river. In the present study, the Tradescantia micronucleus (Trad-MCN) and Tradescantia stamen hair mutation (Trad-SHM) assays were used to evaluate the genetoxicity of water samples collected from 60 different sites along the river. Results indicate that most of the water samples from the tributaries were highly mutagenic, and that pollutants had accumulated in the main river in the Guilin city area from the industrial effluent and city sewage. Both the Trad-MCN and Trad-SHM assays were highly effective for the detection of mutagens in the water samples.     

Changes in the algal composition and water quality of the Sundays River,Karoo, South Africa,from source to estuary

A first survey was done on algae present in the Sundays River from its source to its confluence with the sea. Species found in the upstream sections of the river included indicators of good water quality, but the quality deteriorated downstream with peaks in algal abundance being ascribed to peaks in nutrient concentrations. Cyanobacteria and euglenoids were present in the upper and middle reaches of the river, but were absent downstream. Dinoflagellates became more important downstream, especially in the estuary. Dominant species, reaching high concentrations along the river, included Nitzschia frustulum, Nitzschia capitellata, Carteria klebsii, Chlorella vulgaris and Anabaena species. The presence of the diatom Eolimna comperei is a first record of its occurrence in South Africa. The Sundays River can be described as a brackish, hard water system with high nutrient concentrations in certain sections. The most important contributors to high nutrient concentrations were point sources in the vicinity of towns along the river banks, as well as diffuse sources contributing to high nitrogen concentrations in the fertile Sundays River valley. Increasing salinities were due to pollution, evaporation and agricultural activities in the valley.     

安徽铜陵河流附生细菌多样性

通过对铜陵地区不同河段的上覆水和沉积物的理化性质进行分析,结合聚合酶链式反应-变性梯度凝胶电泳（PCR-DGGE）的方法,研究了铜陵不同河段中附生细菌的多样性及其与环境因子的关系。结果表明,8个河段中上覆水和沉积物的营养水平及重金属含量存在较大差异,不同河段附生细菌的多样性指数也存在差异。数据分析表明,铜陵河流中黄浒河附生细菌的多样性最高,顺安河下游和钟仓河附生细菌的多样性最低。这种差异主要与河段间上覆水和沉积物不同的营养水平、重金属含量水平等因素有关。附生细菌的香农-威纳多样性与上覆水中的氨态氮（NH3-N）、总氮（TN）、总磷（TP）、可溶性正磷酸盐（PO3-4-P）和高锰酸盐指数（COD Mn）呈显著或极显著负相关,与沉积物中镉（Cd）、铜（Cu）和锌（Zn）的含量具有显著或极显著正相关性。     

Hydromorphological restoration of running waters: effects on benthic invertebrate assemblages

1. River restoration has received considerable attention, with much recent focus on restoring river hydromorphology to improve impoverished aquatic communities. However, we still lack a clear understanding of the response of aquatic biota to river restoration. 2. We studied the effects of hydromorphological restoration on benthic invertebrate assemblages in 25 river sites in Germany using standardised methods. Restoration efforts were primarily aimed to restore habitat heterogeneity; correspondingly, habitat diversity increased at most sites. 3. Similarity of benthic invertebrate assemblages between restored and unrestored river sections was low (mean similarity was 0.32 for Jaccard and 0.46 for Sørensen). Community‐based metrics, such as the percentage of Ephemeroptera, Plecoptera and Trichoptera taxa, also differed between restored and unrestored sections. 4. Only three of the 25 restored sections were classified as having ‘good ecological quality’ class according to the European Water Framework Directive criteria; hence, poor water quality is probably one factor impeding recolonisation. 5. Our results show that isolated restoration measures do not necessarily result in positive effects on aquatic biota and that better understanding of the interconnectedness within a catchment is required before we can adequately predict biotic responses to structural river restoration.