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1.
于桥水库浮游植物群落特征   总被引:4,自引:1,他引:3  
于桥水库是天津市惟一饮用水水源地,为了研究该水库浮游植物群落特征,于2012年春、夏、秋对于桥水库浮游植物进行了监测分析。结果表明:该水库共鉴定出绿藻(Chlorophyta)、蓝藻(Cyanophyta)、硅藻(Diatoms)、裸藻(Euglenophyta)、甲藻(Pyrrophyta)、隐藻(Cryptophyta)和黄藻(Xanthophyta)7门114种,群落组成以绿藻-硅藻门为主;浮游植物细胞密度具有明显的季节变化规律,表现为春季较低,夏季急剧增长,到了秋季又有所回落。优势种对于桥水库水质的评价结果表明,春季为中营养水体,夏季为富营养化水体,秋季为中富营养水体。春、夏、秋季于桥水库香农-韦弗多样性指数平均值分别为3.22、2.51和3.17,说明2012年于桥水库春季、秋季为贫营养水体,夏季为中营养水体,且有暴发水华的危险。  相似文献   

2.
于2019-2021年春、秋季在长江干流南京段设置6个调查点位对水体理化因子、底栖动物群落特征开展调查研究。采用典范对应分析方法(CCA)分析了底栖动物与环境因子的响应关系。结果表明,共检出35种底栖动物,分属3门6纲12目19科30属,昆虫纲为优势纲。各监测点位的底栖动物检出种类数相差较大,最多检出21种,最少检出11种。春季优势种为霍甫水丝蚓,秋季优势种为齿吻沙蚕。底栖动物物种密度为2~176个/m^(2),春季的底栖动物平均密度(139个/m^(2))略高于秋季(125个/m^(2)),底栖动物平均密度年度排序为:2019年>2020年>2021年。各监测点位的香农威纳(Shannon-Wiener)多样性指数为2.9~3.5,水质状况处于良好和优秀之间。CCA分析结果表明,高锰酸盐指数和溶解氧对南京段底栖动物群落结构物种时空分布影响较大且大部分群落特征物种分布在含氮营养盐较低的水域,高浓度的含氮营养盐已经对南京段底栖动物产生了负面影响。  相似文献   

3.
为研究于桥水库浮游植物群落结构及其与环境因子的关系,于2014年春夏季进行采样分析。两季共鉴定出浮游植物6门99种,其中绿藻门(Chlorophyta)62种,硅藻门(Diatoms)21种,蓝藻门(Cyanophyta)7种,裸藻门(Euglenophyta)4种,甲藻门(Pyrrophyta)2种,隐藻门(Cryptophyta)2种。春季浮游植物6门86种,第一优势种为绿藻门的四尾栅藻(Scenedesmus quadricauda);夏季浮游植物5门62种,第一优势种为蓝藻门的铜绿微囊藻(Microcystis aeruginosa)。春季浮游植物密度低于夏季,于桥水库浮游植物群落结构具有明显的季节变化规律。RDA分析结果表明,春季采样点的相似性高于夏季,透明度、水温、溶解氧和营养盐是影响于桥水库浮游植物群落组成的关键环境因子。  相似文献   

4.
为了解毕节市倒天河水库和碧阳湖夏秋季浮游植物的群落组成及水质状况,于2013年6月到10月对各采样点的浮游植物每月进行两次采样调查,共鉴定浮游植物19个属,隶属于6门12目,其优势属为盘星藻属和卵形藻属,各采样点浮游植物总密度在夏季均高于秋季。利用3个生物多样性指标,即Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H′)和Pielou均匀度指数(J)来评价各采样点的水质状况,综合多种评价结果显示,倒天河水库和碧阳湖上段总体上为中污染状态,而碧阳湖中下段总体上为中-重污染状态。  相似文献   

5.
洮滆水系湖泊春季浮游植物群落结构和水质生物学评价   总被引:2,自引:0,他引:2  
2014年5月在洮滆水系长荡湖、滆湖和竺山湖布设12个监测点,共采集浮游植物7门109种,平均藻密度为3.94×10~7L~(-1)。Shannon-Wiener多样性指数、Margalef丰富度和Pielou均匀度指数的变化范围分别为0.98~4.18、1.04~3.54和0.18~0.75。上述3种指数和群落优势类群的综合评价结果表明,3个湖泊都处于富营养化状态;12个监测点中S1和S9水质状况最好,S10和S8水质状况最差;3个湖泊评价结果为长荡湖优于滆湖,滆湖优于竺山湖。  相似文献   

6.
为了解淮河干流江苏段着生藻类群落结构时空变化特征及其与环境因子的关系,于2020年11月—2021年7月分4个季节布设5个断面采样调查。结果表明:该河段共检出着生藻类5门36属39种,物种组成以硅藻、绿藻和蓝藻为主,占比分别为35.90%、33.33%和23.08%;着生藻类群落结构虽然在空间上未出现显著差异,但呈现秋季>冬季>春季>夏季的季节变化趋势;alpha多样性指数和beta多样性距离分析均显示,着生藻类群落变化主要体现在季节差异上,夏季和冬季较春季和秋季变异程度更高;环境因子冗余分析(dbRDA)表明,影响着生藻类群落结构在不同季节之间演替的环境因子各不相同,总氮是营养盐指标中唯一显著的影响因子。  相似文献   

7.
为研究抚仙湖浮游植物群落结构及其与环境因子的关系。基于2017年4月(春季)、7月(夏季)、11月(秋季)和2018年2月(冬季)抚仙湖浮游植物和部分水质理化指标的监测数据,分析了浮游植物群落结构特征,通过冗余分析(RDA)研究了影响浮游植物群落结构的主要环境因子,同时运用藻类生物学法和综合营养状态指数法TLI(∑)对抚仙湖水质进行综合评价。结果表明,共鉴定出浮游植物7门54属,绿藻在种类组成上占绝对优势。不同季节浮游植物细胞密度存在明显变化,春季细胞密度最高(401.74×10~4 cells/L),其次为夏季(247.31×10~4 cells/L)和秋季(143.41×10~4 cells/L),冬季最低(88.98×10~4 cells/L)。浮游植物优势属在不同季节有所不同,各季节绝对优势属为伪鱼腥藻属(春季)、转板藻属(夏秋季)、小环藻属和蓝隐藻属(冬季)。Shannon-Wiener多样性指数(H′)和Pielou均匀度指数(J)变化趋势一致,夏季值最高,分别为2.76和0.64,冬季值最低,分别为2.13和0.50。Berger-Parker优势度指数(D)变化与H′和J相反,冬季最高(0.945),夏季最低(0.922)。RDA表明,水温、溶解氧和高锰酸盐指数是影响抚仙湖浮游植物群落结构的主要环境因子。综合评价认为,抚仙湖水质处于贫中营养状态。  相似文献   

8.
随着人类活动的加剧,赤水河生态状况受到越来越多的关注,全面了解赤水河的生态状况,识别影响生态状况的主要环境胁迫因子对于赤水河的管理十分重要。笔者分别于2016年春季(4月)和秋季(9月)对赤水河干流着生硅藻及主要环境指标展开系统调查,春季以曲壳藻属相对丰度、高需氧物种、高磷物种、Shannon-Wiener多样性指数为核心参数,秋季以低需氧物种、物种丰富度、高营养物种为核心参数,构建了着生硅藻多参数指标(D-MMIs)。对赤水河干流生态状况进行评估。结果表明:调查期间,赤水河干流中上游样点水体状况优于下游样点,并且春、秋季赤水河生态状况存在差异。D-MMIs与环境因子的回归分析结果显示:影响春季赤水河生态状况的环境因子为COD,影响秋季赤水河生态状况的环境因子为NH4^+-N。构建的赤水河D-MMIs,能够较好地指示环境胁迫因子对赤水河生态状况的影响,对于指导赤水河的管理实践具有参考价值。  相似文献   

9.
为探究无定河流域浮游动物群落结构特征及其水质状况,于2021年春秋季对无定河干流、6条支流及3个淤地坝水体展开生态调查。共鉴定出浮游动物125种,其中原生动物40种、轮虫54种、枝角类15种、桡足类16种,秋季物种数(103种)高于春季(76种),均以小型浮游动物为主。浮游动物优势种共31种,以臂尾轮虫和龟甲轮虫等富营养型水体指示生物居多,春季优势种优势度整体高于秋季。春季浮游动物平均密度(360.9个/L)和平均生物量(0.600 mg/L)均高于秋季(83.6个/L、0.298 mg/L),且春秋季淤地坝水体中浮游动物平均密度和生物量均高于河流。非度量多维尺度分析也表明:河流与淤地坝2种水体中的浮游动物群落分布存在差异,采用冗余分析进一步探明,主要差异为河流和淤地坝2种水体中影响浮游动物群落分布的环境因子不同,其中化学指标(溶解氧、盐度、亚硝氮、硝态氮、溶解磷、叶绿素a)和物理指标(水深、透明度、浊度)分别是影响河流和淤地坝水体中浮游动物群落结构的主要环境因子。水质生物评价结果显示,春秋季水质均为无定河干流最优,支流次之,淤地坝水质最差,且干流中下游水质优于上游。  相似文献   

10.
为了探究流溪河大型底栖动物的群落结构特征和关键影响因素,于2016年4月(平水期)、7月(丰水期)和11月(枯水期)对流溪河的14个采样断面进行了生态调查,共鉴定出133种大型底栖动物,隶属于55科127属。大型底栖动物平均密度和生物量分别为213 ind./m^2和20. 02 g/m^2,寡毛类和水生昆虫的密度占优势,软体动物的生物量占优势。此外,结果表明流溪河大型底栖动物群落结构具有明显的时空变化。在空间方面,从上游至下游大型底栖动物种类数呈现逐渐减少的趋势,并且支流的大型底栖动物种类数高于干流;从上游至下游大型底栖动物密度和生物量变化无规律,支流大型底栖动物的密度明显高于干流,而生物量却明显低于干流;上游的大型底栖动物Shannon-Wiener多样性指数和Margalef丰富度指数均高于下游,支流的大型底栖动物Shannon-Wiener多样性指数和Margalef丰富度指数均高于干流,而Pielou均匀度指数是支流低于干流。在时间方面,平水期至枯水期大型底栖动物种类数呈现逐渐增加的趋势;密度分布为平水期>枯水期>丰水期,生物量分布规律与密度相似;Shannon-Wiener多样性指数和Margalef丰富度指数均为枯水期最高,平水期最低。流溪河大型底栖动物群落可划分为干流群落和支流群落,群落间物种组成存在显著性差异。综上结果表明:流溪河支流大型底栖动物群落结构较干游更加稳定,下游断面群落受到了较大程度的干扰,生态环境质量状况较差,影响大型底栖动物群落结构的主要因素为有机质、总磷和溶解氧。  相似文献   

11.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

12.
微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬   总被引:25,自引:5,他引:25       下载免费PDF全文
用微波消解-原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸-氢氟酸-过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸-盐酸-过氧化氢体系消解液和硝酸-氢氟酸-过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。  相似文献   

13.
The San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) began in 1993 and is sponsored by 74 local, state, and federal agencies and companies through their discharge or Bay use permits. The RMP monitors water, sediment, toxicity, and bivalve bioaccumulation at 25 sites in the Bay that are considered to represent "background" conditions. Several major environmental issues have been identified by the RMP. Polychlorinated biphenyls and mercury were often above water quality guidelines, and often occurred in fish tissues above U.S. Environmental Protection Agency (U.S. EPA) screening values. Concentrations do not appear to be decreasing, suggesting continuing inputs. Episodes of aquatic toxicity often occurred following runoff events that transport contaminants into the Bay from urbanized and agricultural portions of the watershed. Sediment toxicity occurred throughout the Bay, and has been correlated with concentrations of specific contaminants (chlordanes, polynuclear aromatic hydrocarbons) at some locations; mixtures of contaminants were probably also important. Since the RMP does not monitor all ecosystem components, assessments of the overall condition of the Bay cannot be made. However, in terms of contamination, the RMP samples suggest that the South Bay, and North Bay sites are moderately contaminated.  相似文献   

14.
A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.  相似文献   

15.
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.  相似文献   

16.
The population counts of hydrocarbon-utilising yeasts weremonitored at six sampling stations in the Benin City municipalarea over a four-week period. Although the population countswere relatively constant in each locality, the highest countsoccurred in areas heavily polluted by domestic and industrialeffluents. A total of thirty-five hydrocarbon-degrading yeastswere isolated from soil at the sampling stations usingn-hexadecane as sole carbon source. The isolates were identifiedas belonging to the genera Candida (27 strains), Endomycopsis (4 strains). All the organisms grew on long-chainn-alkane, kerosene, diesel oil and crude oil but failed to growon short-chain n-alkane, aromatic and alicyclic hydrocarbons.Measurement of growth attributes of the isolates usingn-hexadecane, diesel oil and crude oil as substrates showed thatthe Candida species were better utilizers of hydrocarbonsubstrates relative to Endomycopsis and Schizosaccharomyces species.  相似文献   

17.
This paper gives mathematical details and sample applications of SWAGMAN Farm (SWAGMAN, Salt Water and Groundwater Management), a farm-scale hydrologic economic model that integrates agronomic, climatic, irrigation, hydrogeological and economic aspects of irrigated agriculture. The model is capable of determining optimum mix of land use to keep watertable and soil salinity within acceptable limits while maximising the economic returns. Alternatively, the model can simulate water and salt balance and economics of a given cropping preference. Web-based and Geographic Information Systems versions of the model are available for integration with the environmental reporting systems of the irrigation areas.  相似文献   

18.
用火焰原子吸收光谱法测定了苏州开发区26种蔬菜中的铜、锌、铁、锰和镍的含量。蔬菜样品用硝酸高氯酸混合酸进行消解。4次测定值的相对标准差<5%,加标回收率在92%~107%之间。26种蔬菜中铜、锌、铁、锰、镍的含量基本均在世贸组织规定的范围内。  相似文献   

19.
Citation of cyanobacterial cultures from the shores of south west coast of Gujarat, India and their relationship with sea water quality, influenced by extensive pollutant runoff is reported in this study. Intensity of pollution was evaluated by physico-chemical analysis of water. Higher load of suspended solids (60–1000 mg l−1) and nutrients (PO4 P: 1.3–4 μmole l−1 and NO3 N: 12.5–17.8 μmole l−1) were persistent throughout the analysis. Community structure is seen to be influenced by such persistent pollution. Twenty nine cyanobacterial species were isolated belonging to 9 genera of 4 families, with an elevated occurrence of Oscillatoria and Lyngbya species. No heterocystous cyanobacteria were isolated throughout the study.  相似文献   

20.
Using Multiple Taxonomic Groups to Index the Ecological Condition of Lakes   总被引:6,自引:0,他引:6  
Biological indicators of communitiestypically reflect a common environmental signalreflecting the general condition of the ecosystem, as well asindividual signals by indicators differentiallysensitive to particular environmental conditions. Wedescribe here a method of integrating and interpretingsuch indicators from 19 New England lakes for fivetaxonomic groups (diatoms, benthos, zooplankton, fish,and birds). Our approach provides a systematicstandardized way to integrate multiple metrics fromdifferent taxonomic groups by addressing four elementscrucial to analyzing data from multiple indicators: covariate control, re-scaling of data, standardizing the sign of responses, and dimensional reduction. We evaluated the biologicalmetrics against individual environmental stressors andagainst multivariate physicochemical metricscharacterizing general anthropogenic stress among thelakes. The method detected a response to variationin the gross environmental condition of the lakes thatwas correlated across taxa and metrics. In addition,a differential response to near shore conditions wasdemonstrated for fish. The success of the approach inthis study lends support to its general application toecological monitoring involving complex data sets.  相似文献   

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