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951.
The comparison of heavy metal accumulation ratios of some fish species in Enne Dame Lake (Kütahya/Turkey) 总被引:1,自引:0,他引:1
Uysal K Köse E Bülbül M Dönmez M Erdogan Y Koyun M Omeroglu C Ozmal F 《Environmental monitoring and assessment》2009,157(1-4):355-362
The metal accumulation levels for muscle, skin, gill, liver and intestine tissues of some Cyprinidae species (Carassius carassius, Condrostoma nasus, Leuciscus cephalus and Alburnus alburnus) in Enne Dame Lake (Kütahya/Turkey), which is mostly fed by hot spring waters, were investigated. Analyses were performed for copper (Cu), zinc (Zn), manganese (Mn), iron (Fe), cobalt (Co), magnesium (Mg), nickel (Ni), chrome (Cr) and boron (B) using inductively coupled plasma-optic emission spectroscopy (ICP-OES), and cadmium (Cd) using atomic absorption spectrophotometer (AAS) utilizing microwave digestion techniques. The concentrations of the heavy metals found in the fish varied in the follow ing ranges: Cu: < DL-7.04, Zn: 6.96-357.25, Mn: < DL-20.70, Ni: < DL-6.21, Fe: 9.62-2500.33, Cr: < DL-1.74, Co: < DL-0.54, Cd: 0.01-0.27 and Mg: 197.44-904.90 mg/kg wet weight. While B had the second highest concentration in the water of the lake, it was not encountered in any tissue of the investigated species. In all tissues and the species, While the bioaccumulation factors (BAFs) of Mn, Zn, Fe and Cu were remarkably high, the BAFs of Mg, Cr, Co, and B were also fairly low or none. Although the heavy metal accumulation levels for the muscle were generally lower than other tissues, there were some exceptions. Cd level in the muscle of C. carassius was higher than the permissible limit stated by Turkish legislation, FAO and WHO. The mean metal amounts for all the investigated tissues and species are statistically compared and discussed in this study. 相似文献
952.
Coşkun M Yurukova L Cayir A Coşkun M Gecheva G 《Environmental monitoring and assessment》2009,157(1-4):529-537
First cross-border atmospheric pollution of 11 heavy metals and toxic elements assessed by Hypnum cupressiforme was reported for a part of Southeastern Europe (Southeastern Bulgaria and European Turkey). Moss monitoring technique followed the main requirements of European Moss Survey. Moss samples were collected in April 2006 both in Bulgaria and Turkey. Concentration of Al, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, and Zn were determined by ICP-AES. Interlaboratory parallel calibration (exchanged four moss samples from each country), standard reference moss materials (M2 and M3) results ensured the study. ANOVA showed no differences between measured results in both laboratories at the 99% confidence level. Principle Component Analyze proved two factors: F1 group of Al, As, Cd, Cr, Fe, Ni, and V and F2 of Cu, Pb, and Zn as main atmospheric pollutants. Results obtained showed approximately Cu and Pb high concentrations around Istanbul and Burgas and Zn pollution in Istanbul district. Arsenic cross-border atmospheric pollution in the study area of Southeastern Europe was found. 相似文献
953.
Atmospheric visibility impairment has gained increasing concern as it is associated with the existence of a number of aerosols as well as common air pollutants and produces unfavorable conditions for observation, dispersion, and transportation. This study analyzed the atmospheric visibility data measured in urban and suburban Hong Kong (two selected stations) with respect to time-matched mass concentrations of common air pollutants including nitrogen dioxide (NO(2)), nitrogen monoxide (NO), respirable suspended particulates (PM(10)), sulfur dioxide (SO(2)), carbon monoxide (CO), and meteorological parameters including air temperature, relative humidity, and wind speed. No significant difference in atmospheric visibility was reported between the two measurement locations (p > or = 0.6, t test); and good atmospheric visibility was observed more frequently in summer and autumn than in winter and spring (p < 0.01, t test). It was also found that atmospheric visibility increased with temperature but decreased with the concentrations of SO(2), CO, PM(10), NO, and NO(2). The results showed that atmospheric visibility was season dependent and would have significant correlations with temperature, the mass concentrations of PM(10) and NO(2), and the air pollution index API (correlation coefficients mid R: R mid R: > or = 0.7, p < or = 0.0001, t test). Mathematical expressions catering to the seasonal variations of atmospheric visibility were thus proposed. By comparison, the proposed visibility prediction models were more accurate than some existing regional models. In addition to improving visibility prediction accuracy, this study would be useful for understanding the context of low atmospheric visibility, exploring possible remedial measures, and evaluating the impact of air pollution and atmospheric visibility impairment in this region. 相似文献
954.
In the paper water supply profile of Turkey was examined. In this scope, the questionnaire survey conducted by Turkish Statistical Institute in 2004 to investigate annual amount of water abstracted to drinking water networks by type of resources in 81 provinces was evaluated. In the questionnaire, sources were grouped under five categories as spring, (artificial) lake, river, reservoir and well. Due to the complex and multivariate characteristics of the data sets, to replace a large collection of variables with a smaller number of factors the statistical method "factor analysis" was performed. Results revealed that, water supply systems in the country were mainly governed by groundwater sources (well and/or spring). However, in the northeastern part of the country, rivers were allocated for drinking water supply. On the other hand, reservoir dependent cities were densely located in Marmara, Central Anatolia and Southeast Anatolia Regions. This study showed that statistics based classification methods assist decision makers to extract information from multidimensional complex data sets representing environmental conditions. 相似文献
955.
A new method for separation and preconcentration of trace amounts of Cu(II), Ni(II), Pb(II), Cd(II) and Mn(II) ions in various matrices was proposed. The method is based on the adsorption and chelation of the metal ions on a column containing Amberlite XAD-1180 resin impregnated with 1-(2-thiazolylazo)-2-naphthol (TAN) reagent prior to their determination by flame atomic absorption spectrometry (FAAS). The effect of pH, type, concentration and volume of eluent, sample volume, flow rates of sample and elution solutions, and interfering ions have been investigated. The optimum pH for simultaneous retention of all the metal ions was 9. Eluent for quantitative elution was 20 ml of 2 mol l(-1) HNO(3). The optimum sample and eluent flow rates were found as 4 ml min(-1), and also sample volume was 500 ml, except for Mn (87% recovery). The sorption capacity of the resin was found to be 0.77, 0.41, 0.57, and 0.30 mg g(-1) for Cu(II), Ni(II), Cd(II), and Mn(II), respectively. The preconcentration factor of the method was 200 for Cu(II), 150 for Pb(II), 100 for Cd(II) and Ni(II), and 50 for Mn(II). The recovery values for all of the metal ions were > or = 95% and relative standard deviations (RSDs) were < or = 5.1%. The detection limit values were in the range of 0.03 and 1.19 microg l(-1). The accuracy of the method was confirmed by analysing the certified reference materials (TMDA 54.4 fortified lake water and GBW 07605 tea samples) and the recovery studies. This procedure was applied to the determination of Cu(II), Ni(II), Pb(II), Cd(II) and Mn(II) in waste water and lake water samples. 相似文献
956.
Freshwater clam Corbicula fluminea, a surrogate species in metal toxicity testing, is a promising bioindicator of impairment in aquatic ecosystems. Little is known, however, about the relationship between clam valve daily rhythmic response and metal bioavailability related to a metal biological early warning system (BEWS) design. The purpose of this study was to link biotic ligand model (BLM)-based bioavailability and valve daily rhythm in C. fluminea to design a biomonitoring system for online in situ detection of waterborne copper (Cu). We integrated the Hill-based dose-time-response function and the fitted daily rhythm function of valve closure into a constructed programmatic mechanism. The functional presentation of the present dynamic system was completely demonstrated by employing a LabVIEW graphic control program in a personal computer. We used site-specific effect concentration causing 10% of total valve closure response (EC10) as the detection threshold to implement the proposed C. fluminea-based Cu BEWS. Here our results show that the proposed C. fluminea-based BEWS could be deliberately synthesized to online in situ transmit rapidly the information on waterborne bioavailable Cu levels under various aquatic environmental conditions through monitoring the valve daily rhythmic changes. We suggested that the developed C. fluminea-based dynamic biomonitoring system could assist in developing technically defensible site-specific water quality criteria to promote more efficient uses in water resources for protection of species health in aquatic environments. 相似文献
957.
Identification of soil heavy metal sources from anthropogenic activities and pollution assessment of Fuyang County, China 总被引:4,自引:0,他引:4
Zhang XY Lin FF Wong MT Feng XL Wang K 《Environmental monitoring and assessment》2009,154(1-4):439-449
Understanding regional variations of soil heavy metals and their anthropogenic influence are very important for environmental planning. In this study, 286 surface soil samples were collected in Fuyang county, and the 'total' metals for copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd) and nickel (Ni) were measured in 2005. Statistic analysis showed that Cu, Zn, Pb and Cd had been added by exterior factors, and Ni was mainly controlled by natural factors. The combination of multivariate statistical and geostatistical analysis successfully grouped three groups (Cu, Zn and Pb; Cd; and Ni) of heavy metals from different sources. Through pollution evaluation, it was found that 15.76% of the study area for Cu, Zn and Pb, and 46.14% for Cd suffered from moderate or severe pollution. Further spatial analysis identified the limestone mining activities, paper mills, cement factory and metallurgic activities were the main sources for the concentration of Cu, Zn, Pb and Cd in soils, and soil Ni was mainly determined by the parent materials. 相似文献
958.
A comprehensive method for aeolian particle granulometry and micromorphology analyses 总被引:1,自引:0,他引:1
Zaady E Dody A Weiner D Barkai D Offer ZY 《Environmental monitoring and assessment》2009,155(1-4):169-175
The aim of this study was to use a new approach to investigate aeolian particle granulometry and micromorphology. Taking total aeolian deposition into account, we used parameters such as, particle area, perimeter, shape analysis for particle roughness (area/perimeter) and elongation (long/short axis). These parameters were analyzed on temporal and spatial scales at four study sites in the eastern Negev Desert, Israel. The total collection of particles was sorted into three size groups based on particle area to facilitate comparison. The classic definition of particle size (equating particle length with particle diameter) produced relatively small variations among the three size classes (25-38.6%). Our proposed comprehensive method demonstrated significant variation among the three size classes (13.9-60.8%), e.g. the classic method placed 36.4% of the particles in size class two while the new method placed 60.8% of the particles in this size class; the differences were even more significant regarding size class 3 (38.6% vs. 13.9%, respectively). The classic method did not facilitate investigation of particle roughness and elongation. With this new approach, it was possible to clearly define the particles by size class, based on these characteristics. With roughness, the variation among size classes 2 and 3 was about 27%. With elongation, the variation among size classes two and three was about 21%. Applying similar investigation method to study the aeolian particle granulometry and micromorphology can better facilitate more detailed calculation of particle size distribution, roughness and elongation. 相似文献
959.
Fluoride occurrence and assessment of exposure dose of fluoride in shallow aquifers of Makur, Unnao district Uttar Pradesh, India 总被引:1,自引:0,他引:1
The water samples from the shallow aquifers of Makur, Unnao district, Uttar Pradesh, was analyzed for fluoride content (F( - )) and other water quality parameters such as pH, EC, CO(3) (2-), HCO(3) (-), Cl( - ), Na( + ), Ca(2 + ), Mg(2 + ) and RSC. It was found that the F( - ) concentration of water varied between 1.05 to 13.9 mgl( - 1) which exceeded the maximum desirable limits of 1.0 mgl( - 1) of F( - ) as laid down by BIS and 68% of water exceeded maximum permissible limits of 1.5 mgl( - 1) as prescribed by WHO. The correlation study of fluoride indicated that F( - ) has a significant (p < 0.05) positive relationship with pH (r = +0.59) and RSC (r = 0.54), while a significant negative correlation with Ca+Mg (r = -0.53) and Mg (r = -0.49). The exposure doses of fluoride in infants was found between 0.35 to 3.26 mg kg( - 1)day( - 1) (if dug well water was used) whereas 0.36 to 4.63 mg kg( - 1)day( - 1) (when shallow hand pumps) The exposure doses of water in case of children (20 kg body weight) varied between 0.157 to 1.47 mg kg( - 1)day( - 1) (for dugwell) and 0.162 to 2.08 mg kg( - 1)day( - 1) (for shallow hand pumps) whereas in case of adults (70 kg body weight), it varied between 0.09 to 0.839 mg kg( - 1)day( - 1) (for dugwell) and 0.092 to 1.19 mg kg( - 1)day( - 1) (shallow hand pumps) which is quite high against the standard value of 0.05 mg/kg/day which is the minimum risk level (MRL) calculated by the Agency for Toxic Substances and Disease Registry (ATSDR). The maximum exposure dose to fluoride for adults in the study area found to be 23.8 times higher than the ATSDR's MRL. 相似文献
960.
We developed a systematic process to evaluate state/tribal bioassessment programs to provide information about the rigor of the technical approach. This is accomplished via on-site interviews to produce an evaluation that assigns one of four levels of rigor as an outcome. Level 4 is the most rigorous and reflects a technical capacity to accurately determine incremental condition and support management programs. The remaining three levels are less able to assess incremental condition and are appropriate for only some management support needs. Accurately determining impairment and diagnosing pollution-specific stressors are fundamental tasks that states/tribes must accomplish to provide management support. This goal is fulfilled to varying degrees by most states/tribes. The evaluation employs a checklist and a sliding scale of rigor for 13 technical elements. Feedback is provided to each state/tribe via a technical memorandum that describes the technical components of the monitoring program, highlights strengths, and recommends improvements for specific technical issues. This can be used to refine the bioassessment and monitoring programs to better support management programs. The results of 14 state/tribal evaluations are included here. The majority (nine states, one tribe) revealed that most operate at level 2 with developmental activities that will elevate the level of program rigor already underway. Two states operate level 4 programs and each have numeric biocriteria and refined designated uses in their water quality standards. This is the ultimate goal of the process of engaging states in the development of bioassessment programs in the U.S. 相似文献