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1.
基于2011—2015年茹河彭阳水质监测断面的水质数据,采用物元分析法对其断面水质进行评价;建立适用于该监测断面的马尔可夫预测模型对断面水质类别进行预测;同时依据平稳分布对各类水质的重现期作了分析。结果表明:彭阳水质监测断面水质为Ⅲ类;对马尔可夫链预测模型进行验证,满足预测精度;2015年9月和11月的水质类别预测结果均为Ⅲ类,且Ⅲ类水质出现的周期最短,属河流水质常态,其重现期为4.9个月,整体水质较好。  相似文献   

2.
王灵  郑江  杨永红  张江丽 《干旱环境监测》2012,26(3):145-148,192
通过对乌鲁木齐河近十年(2001—2010年)水质监测数据的分析,结果表明,"十一五"期间乌鲁木齐河上游水质较好,为Ⅰ类或Ⅱ类水质,中下游均受到较为严重的有机污染,为劣Ⅴ类水质,主要污染物为粪大肠菌群、化学需氧量、氨氮、石油类;各监测断面水质总体保持稳定,水质污染形势依然严峻。水污染治理措施取得一定成效。与"十五"相比,"十一五"期间乌鲁木齐河水质明显改善,综合污染指数进一步下降,跃进桥断面水质类别由Ⅱ类水质变为Ⅰ类,英雄桥断面水质类别由Ⅲ类水质变为Ⅱ类。根据分析评价结果,提出了改善水环境质量的对策和建议。  相似文献   

3.
汉丹江(陕西段)水质变化特征分析   总被引:1,自引:1,他引:0  
基于2008—2012年陕西省境内汉江、丹江干流14个断面的水质监测数据,采用单因子评价法、平均综合污染指数法和秩相关系数法等对该段水体的水质变化特征进行研究。结果表明,汉丹江(陕西段)断面水质以Ⅱ类、Ⅲ类为主,水质总体为优;水质综合污染状况呈下降趋势,其中汉江下降趋势显著;水质综合污染状况空间差异和区域分布特征明显,城区段污染大于郊区,各行政区段河流下游污染大于上游。流域水质主要受有机污染和营养盐因子影响,水体污染源主要来自城镇生活源和农业面源,工业源占比不大且排放行业较为集中。  相似文献   

4.
评估国家重点生态功能区县域的水环境保护成效,对国家生态环境保护与修复决策具有重要意义。基于2012—2020年地表水监测数据及污水排放和气候数据,评估并分析了国家重点生态功能区县域的地表水环境状况。研究表明,2012—2020年国家重点生态功能区县域地表水水质持续改善,Ⅰ~Ⅲ类水质断面的比例从89.14%上升到93.47%,但部分地区地表水环境质量仍有待提升,尤其是内蒙古北部、山西西部、陕西北部和京津冀地区。4类生态功能区中,生物多样性维护区地表水水质最好,其次为水源涵养区,再次为水土保持区,防风固沙区最差。化学需氧量和高锰酸盐指数是国家重点生态功能区县域地表水的主要超标项,2012—2020年该两项指标超标断面占总超标断面的比例的多年平均值分别为24.22%和17.29%。县域年化学需氧量排放量及年降水量是影响相关地区地表水环境质量的重要因素。建议增加总氮作为国家重点生态功能区县域地表水质量评价指标,并在进行水环境评价时充分考虑当地的背景情况。  相似文献   

5.
岷江流域水质状况评价及变化趋势分析   总被引:1,自引:0,他引:1  
通过岷江断面水质监测数据,利用内梅罗污染指数法进行水质评价,分析了2009—2013年岷江干流水质情况及其变化趋势。阐述了2013年岷江流域水质空间分布、月季变化情况。提出了流域水质污染防治建议。结果表明,岷江干流上游水质较好、中游较差、下游略有好转,体泉河等部分岷江支流水质较差。2013年全年来看,4—5月份水质较差,7—10月相对较好。  相似文献   

6.
采用单因子评价法、水质类别比例法、平均综合污染指数法、SPSS统计和相关性分析方法,调查分析绛溪河简阳段水环境特征,提出污染防治建议。本次调查结果表明:(1)监测断面氨氮、总磷、化学需氧量达到Ⅲ类水质标准的比例分别为72.2%、11.1%、22.2%,污染最重的因子是总磷;(2)部分断面指标不能完全达标,从上游至下游水质变差;(3)支流海螺河、赤水河对干流污染贡献大;(4)平均综合污染指数与总磷的相关性高于氨氮、化学需氧量,河流污染受磷元素影响最为显著;(5)氨氮与总磷显著相关,河流氨氮、总磷同源性较好。  相似文献   

7.
2005年8月,14个控制断面中有9个断面达到Ⅲ类水质标准,达标率为64·3%。符合Ⅳ、Ⅴ类水质标准的断面分别为4个、1个,分别占28·6%和7·1%。与上月相比,总体水质基本持平,其中10个断面水质持平,3个断面水质好转,1个断面水质下降。与2004年同期相比,14个断面中有9个断面水质持平,5个断面水质好转。摘自江苏省环境监测中心《环境监测工作通讯》2005年第8期南水北调东线江苏段2005年8月水质状况  相似文献   

8.
改进水环境质量评价方法对于提高水环境管理水平具有重要意义。根据传统灰色关联分析原理,采用"中心化"的灰色关联无量纲化处理方法,对丹江口流域2012年河流中11个典型断面水体污染因子进行评价。结果表明,参评的11个断面中有9个符合地表水Ⅱ类水质标准,2个断面符合地表水Ⅳ类水质标准,整体水质满足国家南水北调水源地水质标准要求,改进的灰色关联分析方法在评价水质时较为科学、合理。  相似文献   

9.
新疆地表水水质现状分析   总被引:2,自引:0,他引:2  
以2008年新疆环保系统的水质例行监测结果为基础,分析了新疆地表水水质现状。结果显示,全疆57条监测河流Ⅰ~Ⅲ类优良水质断面比例为81.9%,29座监测湖库Ⅰ~Ⅲ类优良水质比例为55.2%,总体上全疆地表水污染尚不严重,水质污染主要集中在少数流经城市河流的下游河段以及尾间湖和纳污水库,且不同区域间的水体污染程度和比例存在一定差别。  相似文献   

10.
2005年10月,太湖湖体平均水质为Ⅳ类,富营养化程度平均处于中富营养水平。与《太湖水污染防治“十五”计划》湖体水质目标相比,西部沿岸区和东部沿岸区有超标现象,其余湖区各项指标均达到水质目标要求。江苏省境内太湖流域出入湖河流21个控制断面(苏州苏东河越溪桥因河道整治无法采样)中,有14条河流水质符合2005年水质目标类别要求,达标率为70.0%;9条主要人湖河流中有6条河流水质达标,达标率为66.7%。45个环湖河流行政交界断面中,  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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