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1.
地表水中石油类红外法与紫外法测定结果的比对   总被引:3,自引:1,他引:3  
进行了红外光度法与紫外分光光度法测定混合油样、闽江干流水样和内河水样中石油类的比对试验 ,试验表明 ,两法所测结果相差较大 ,以红外法所得结果较符合水体实际情况 ,提出了红外光度法测定时的注意事项  相似文献   

2.
新疆地下水中农药污染水平调查   总被引:6,自引:0,他引:6  
报道了新疆产棉区的莎车、英吉沙两县20个采样点的地下水受有机磷、有机氯和菊酯类农药污染的调查结果。结果表明:分别有55%(11)、30%(6)、25%(5)、15%(3)和5%(1)的水样受到了敌敌畏、敌百虫、功夫菊酯、六六六和甲拌磷的污染。其中4份水样中的敌敌畏(3)敌百虫(1)含量超过了《城市给水工程规范》(GB50282-1998)规定的生活饮用水水质指标限值(<0.1μg/L)。  相似文献   

3.
以钢丝绳产业集聚区内的土壤为研究对象,采集和分析产业区中心河两边淹水环境下的水稻田、少用受污染河水灌溉的棉花田及不用受污染河水灌溉的蔬菜地样本,结果表明,产业区内土壤中铅和锌的含量明显高于产业区外。产业区内除水稻田土壤中铅的质量比超过评价参比值外,其他灌溉方式下土壤中铅和锌的质量比均未超过《土壤环境质量标准》(GB 15618-1995)中的二级标准(pH值>7)。统计分析表明,土壤中的重金属含量与废水灌溉方式有关,该产业区内土壤外源重金属来自钢丝绳产业的可能性很大。在不同的灌溉方式下,土壤剖面样品中的重金属含量随着土壤深度增加呈现降低的趋势,2010年和2011年的测定结果无显著差异。  相似文献   

4.
为调查四川省地表水体中放射性物质铀(U)的含量,评价居民摄入地表水体中U导致的健康风险,在四川省主要地表水系中共设置23个监测断面,于2016—2021年检测了U的放射性水平,并根据健康风险评价模型对居民的健康风险进行评估。结果表明:四川省地表水体中U的质量浓度为0.16~3.6 μg/L,参照《生活饮用水卫生标准》(GB 5749—2022),均合格;不同年份、不同地表水体中U的放射性水平间的差异均无统计学意义(P>0.05);不同水期U的放射性水平间的差异有统计学意义(P<0.05)。各年龄组通过饮水、水体浸没途径摄入U所致总年均待积有效剂量均<0.1mSv;对各年龄段居民的总致癌风险为4.18×10-9 ~2.24×10-8 ,均低于世界卫生组织(WHO)和国际放射防护委员会(ICRP)发布的最严格控制限值。全省主要地表水体中U对各年龄组都是安全的。  相似文献   

5.
为研究广东省某矿区开展生态修复多年后下游农田土壤的金属污染状况,选取该矿区下游某村周边农田土壤及灌溉水渠作为研究对象,对该区域采集了40个土壤表层样本和8个水体样本,利用Arcgis软件对农田土壤样品中As、Cu、Cd、Pb、Zn、Mn和Fe2O3的质量分数进行克里金空间插值,解析该区域农田土壤金属的空间分布特征;采用综合污染指数法和潜在生态风险指数法对该区域耕作层土壤中As、Cu、Cd、Pb、Zn和Mn进行风险评价。结果表明,40个土壤样品中As、Cd、Cu、Zn和Pb的超标率分别为77.5%、70%、87.5%、27.5%和67.5%,说明调查区域农田土壤污染属于多金属复合污染,且对农作物的生产和安全产生巨大的威胁。部分土壤样品中As、Pb和Cd含量超过了中国农用地土壤污染风险管制值,需采取严格管控措施。通过分析土壤金属的空间分布,发现土壤金属含量超标点位主要位于灌溉口与受污染河流周边,且含量与离灌溉口距离成反比。结合目前灌溉水样中的金属均未超标的情况,得出该区域农田土壤污染是由该矿区生态环境修复前所产生的含金属灌溉水导致土壤中金属的积累...  相似文献   

6.
化学耗氧量(COD)、生化需氧量(BOD)以及总有机碳(TOC)、总耗氧量(TOD),它们都是评价水质好坏的重要指标。COD是指示水体受有机物及无机还原性物质污染的主要指标,而水样受有机物污染是普遍的,因此化学耗氧量(COD)也可作为有机物相对含量的指标之一。生化需氧量(BOD)  相似文献   

7.
利用单因子指数法和综合污染指数法,对乌鲁木齐市水磨河4个监测断面水质情况进行了评价。结果表明:搪瓷厂泉为超标水体;七纺桥为Ⅴ类水体,达到农业灌溉用水要求;联丰桥断面、米泉桥断面为劣Ⅴ类水体,没有达到农业灌溉用水要求。生活源和工业源化学需氧量、氨氮等污染物的排入对水体产生了严重影响,造成水体重污染。  相似文献   

8.
采用等离子体发射光谱法和原子荧光光谱法对长江水系(镇江段)水体和水生生物中的5种重金属元素含量进行监测,对结果采用单项污染指数评价法和内梅罗综合指数进行分析评价。结果表明,长江水系(镇江段)8个水体采样点中水体的Cd、Cr、Pb、As含量的平均值为0.074、0.015、1.469、2.409μg/L,单项污染指数评价和内梅罗综合指数评价均为未超标及清洁等级;长江水系(镇江段)2个水生生物采样点中2种水生生物中的Cd、Cr、Pb、Hg、As含量的平均值分别为0.004、0.400、0.308、0.001、0.026 mg/kg和0.020、0.200、0.500、0.002、0.041 mg/kg,单项污染指数评价均未超标,内梅罗综合指数评价显示,长江水系(镇江段)中水生生物受Pb不同程度的污染,部分污染指标超标但并不严重。  相似文献   

9.
以煤矿区及煤矸石的污染特征为依据,选取16种EPA优先控制多环芳烃(PAHs)污染物,采用高效液相色谱法对不同堆积年限的矿区煤矸石山周围塌陷区的水体样品进行测试,分别分析此类水体中单个PAHs和总PAHs的分布情况及水体中PAHs不同环数的组成情况,并采用风险商值法进行水体生态风险评价,指出此类水体的不当开发利用会引起人体健康危害。  相似文献   

10.
五里湖—梅梁湖磷污染调查   总被引:8,自引:2,他引:6  
通过对五里湖-梅梁湖洗涤剂“禁(限)磷”前后水体磷含量变化的调查,表明,禁止使用含磷洗衣粉两年后,五里湖水体中总磷含量降低20%,梅梁湖总磷含量也有下降趋势,但是五里湖近5年的总磷监测结果均超过《地表水环境质量标准》(GHZB1-1999)中Ⅴ类标准。指出,洗衣粉中所含的磷是湖区磷污染的重要来源,而水体磷负荷的大量来源是人体排泄、农业面源(含畜禽、水产养殖)和工业点源。提出,“治前”(禁磷)是前提,“治后”(除磷)是手段,根本的一条是控制入湖的总磷量,维持湖体生态平衡。  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.
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   

20.
We determined concentrations of selected trace elements inlivers, kidneys and blood samples from common eiders (Somateria mollissima borealis) from the eastern Canadianarctic during 1997 and 1998. Concentrations of totalmercury and organic mercury were generally low in the liversof these birds (less than 6 and 4 g g–1 dry wt,respectively). Selenium ranged between 11–47 g g–1 inlivers. Renal cadmium concentrations were among the highestever published for this species (range: 47–281 g g–1). The regressions of log-transformed concentrations ofthese trace elements in blood samples on those in liver orkidney were significant (all P-values < 0.05) andpositive. However, except for organic mercury (RM 2 = 0.83), the co-efficients of determination were low tomoderate (range of R 2: 0.26–0.52), suggesting poorto moderate predictive capability. Furthermore, therelationships between total mercury in blood and liverchanged between 1997 and 1998, suggesting that it would notbe possible to predict consistently, concentrations ofmercury in blood from those in liver based on samples takenin one year. Blood samples can be used to determineconcentrations of these trace elements in common eiders (andprobably other sea duck species as well). The use of bloodsamples is especially warranted when it is undesirable tokill the animal such as when working with rare or endangeredsea duck species or when the objective is to relate traceelement exposure to annual survival rates. However, thepredictive equations developed here should not be used topredict expected concentrations in one type of tissue fromthose in the other.  相似文献   

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