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1.
In this study, 79 bulk precipitation samples were collected at two sampling sites near Büyükçekmece Lake, one of the important drinking water sources of Istanbul, for the period of October 2001 to July 2002. The study comprised the determination of trace and toxic metals concentrations in rain water. The concentrations of the metals in this study were found to be higher than those reported by other researchers around the world. The solubility of toxic metals was found in the order of Cd > Cu > V > Zn > Ni > Pb > Cr. Solubility of metals under acidic conditions (pH < 5.5) was approximately five times higher than those under neutral conditions with Cd as the most soluble metal (50% soluble). Statistical evaluations including seasonal variations, crustal enrichment factors, and correlation matrix were discussed to identify the possible sources of these pollutants. The study revealed that anthropogenic elements were highly enriched especially for Cd > Cu > Pb which were found to be highly enriched. Significant portion of Cu and Pb could be increased by the effect of local sources like cement industry in the area; however, the rest of the investigated trace metals could be brought to the sampling site by long-range transport to the Büyükçekmece Lake watershed area.  相似文献   

2.
The aim of this study is to determine the total metal (aluminum, copper, manganese, nickel, lead, zinc, cadmium, iron, mercury) contents of dominant shrimp species and sediments present at 1–50 m depths of the Northern Inner Shelf of the Sea of Marmara. Shrimp and sediment samples were collected from four regions (Büyükçekmece, Silivri, Tekirda?, ?arköy) and from different depths (1, 5, 10, 20, 30, 50 m) at each region in September and November of 2003. Three shrimp species [Palaemon adspersus (Rathke, 1937), Palaemon serratus (Pennant, 1777), Parapenaeus longirostris (H. Lucas, 1846)] were identified to be dominant as a result of the examination on the obtained samples. Heavy metal contents of these three species were determined and the results were compared with the acceptable treshold values of the Seafood Standards and also with available literatures. The Cu contents were found to be higher than the treshold limits in all samples except P. longirostris from Silivri, also the Cd contents in all samples except P. adspersus from Büyükçekmece, the Zn contents only in P. adspersus and P. longirostris from Tekirda?, and the Pb contents in all species from all regions. These high values are the indicator of industrial pollution. There is not any data in the Seafood Standards about Mn, Ni, Fe and Al contents in shrimp species. The values of these metal contents were given in the present study. The examination of total metal distributions in bottom surface sediment samples in the Northern Inner Shelf of the Sea of Marmara showed that the determined values were higher than the shale average at some depths of examined stations.  相似文献   

3.
Physical and chemical parameters have been analyzed in water samples from a brackish water lagoon, Küçükçekmece, located on the western outskirts of Istanbul. Samples were collected every two months for a year from nine sampling stations. Of the parameters measured, temperature, pH, salinity, nitrate and phosphate showed changes when compared with the previously published data. The lagoon was found eutrophic as it was reported previously. Sulphate and COD levels were higher when compared with the standards established by the Turkish Water Pollution and Control Regulation. Additionally, concentrations of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in water and bottom sediments were measured and compared with the standards established by the Turkish Water Pollution and Control Regulation and with the previously published data. The results were analysed statistically with respect to location and any relationships between the concentration of the elements in corresponding water and sediment samples were examined. Principal Component Analysis of water samples allowed us to discriminate three areas affected mainly by heavy metal contamination, possibly due to industrial, commercial and/or urban activities. Generally, the concentrations of the heavy metals were higher at stations near the three estuaries, suggesting a direct influence of the three creeks on the pollution of the Küçükçekmece Lagoon. Although elevated levels of Cd were recorded in several water samples, it was not detected in sediment. On the other hand, a particularly high level of Cr pollution was recorded most of the water and sediment samples.  相似文献   

4.
红枫湖是贵阳市重要的饮用水源地,由于城市化发展及诸多原因,自20世纪90年代以来水质受到一定程度污染.1995年省委、省政府立法保护红枫湖,并成立"两湖"领导小组,对红枫湖流域进行综合整治,使其水质得到不断改善.至2019年,红枫湖水体环境质量已经达到治理预期目标,各个监测点位水质从局部劣Ⅴ类改善至整体Ⅱ类.笔者回顾了...  相似文献   

5.
Köyce?iz Lake is located in the south-western part of Turkey. The area between the Köyce?iz Lake and the Mediterranean Sea is covered with four small lakes and several canals. The surroundings of the lake, canals and forests have a great potential as a reproduction areas for Mediterranean Sea turtles (Caretta caretta) and sheltering place for various animals. In the vicinity of this system there are agricultural areas and small settlements. In this region the most important economic activities are tourism and fisheries. However, the lake is currently threatened by pollution because of (1) non-point source pollution (agriculture); (2) point sources (land-based fish farms); (3) inefficient sewerage systems; (4) uncontrolled soil erosion in its drainage basin; (5) inappropriate flood control measures; and (6) channel traffic. This study evaluates the influence of its influent creeks namely Namnam and Yuvarlakçay Creek on the water quality of Köyce?iz Lake, mainly because the creeks are believed to be responsible for the major pollutant load reaching the lake. Accordingly, this study demonstrates (1) change in the water quality of Köyce?iz Lake from 2006 to 2007; (2) the water quality classification of the major influent creeks feeding Köyce?iz Lake; and (3) how land-based fish farm influences Yuvarlakçay Creek water quality in a Köyce?iz–Dalyan Specially Protected Area.  相似文献   

6.
In the present study, a seasonal and non-seasonal prediction of boron concentrations time series data for the period of 1996–2004 from Büyük Menderes river in western Turkey are addressed by means of linear stochastic models. The methodology presented here is to develop adequate linear stochastic models known as autoregressive integrated moving average (ARIMA) and multiplicative seasonal autoregressive integrated moving average (SARIMA) to predict boron content in the Büyük Menderes catchment. Initially, the Box–Whisker plots and Kendall’s tau test are used to identify the trends during the study period. The measurements locations do not show significant overall trend in boron concentrations, though marginal increasing and decreasing trends are observed for certain periods at some locations. ARIMA modeling approach involves the following three steps: model identification, parameter estimation, and diagnostic checking. In the model identification step, considering the autocorrelation function (ACF) and partial autocorrelation function (PACF) results of boron data series, different ARIMA models are identified. The model gives the minimum Akaike information criterion (AIC) is selected as the best-fit model. The parameter estimation step indicates that the estimated model parameters are significantly different from zero. The diagnostic check step is applied to the residuals of the selected ARIMA models and the results indicate that the residuals are independent, normally distributed, and homoscadastic. For the model validation purposes, the predicted results using the best ARIMA models are compared to the observed data. The predicted data show reasonably good agreement with the actual data. The comparison of the mean and variance of 3-year (2002–2004) observed data vs predicted data from the selected best models show that the boron model from ARIMA modeling approaches could be used in a safe manner since the predicted values from these models preserve the basic statistics of observed data in terms of mean. The ARIMA modeling approach is recommended for predicting boron concentration series of a river.  相似文献   

7.
为全面提升江苏省水环境的监控预警能力,我省在太湖流域相关市县建立了覆盖省市交界断面、出入湖口门、饮用水源地的全方位自动监控网络,为相关自动监控系统的技术框架构建提供了重要参考依据,弥补了现行环境监测体系的不足,为太湖流域的监控预警、生态补偿、流域考核等工作提供了重要参考。  相似文献   

8.
In this study, heavy metal contents of groundwater from the Mersin aquifer were determined with photometric methods and used to determine the main factors controlling the pollution of groundwater in the area. Using MapInfo GIS software, spatial analysis and integration were carried out for mapping drinking water quality in the basin. From the photometric heavy metal analysis, it is inferred that the excess concentration of Fe, Ni, Mn, Mo and Cu at some locations is the cause of undesirable quality for drinking purposes. Similarly, the EC thematic map shows that considerable areas in the basin are having high salinity hazards. The reason for excess concentration of various heavy metals is the industrial activities and petroleum pipelines and salinity levels show the sea water intrusion.  相似文献   

9.
This paper presents an application of water quality mapping through real-time satellite and ground data. The Lake Beysehir which is the largest freshwater lake and drinking water reservoir in Turkey was selected as the study area. Terra ASTER satellite image is used as remote sensing data source for water quality mapping in addition to simultaneously performed in-situ measurements. Ground data is collected simultaneously with the ASTER overpass on June 09, 2005 over the Lake Beysehir. The spatial distribution map is developed by using multiple regression (MR) technique for water quality parameter, which is chlorophyll-a (chl-a). The results indicate that simultaneous ground and satellite remote sensing data are highly correlated (R (2) > 0.86). In the image processing step, geometric correction, image filtering and development of water quality map procedures are performed with the ERDAS Imagine and ArcGIS 9.0 software. The trophic status of Lake Beysehir is considered to be oligotrophic with an average 1.55 microg/l chl-a concentration.  相似文献   

10.
根据昆明市环境监测中心2004~2008年连续5年对昆明辖区牛栏江流域河道及库区水质监测的结果,对牛栏江-滇池补水工程昆明辖区流域的水环境质量现状进行了分析研究,探讨了该流域段水污染的时空分布,就此提出水污染防治对策措施建议.  相似文献   

11.
A sediment quality index (SQI) was developed using an equation incorporating three elements; scope--the % of variables that did not meet guidelines; area frequency--the % of failed tests divided by the total number of tests in a group of sites; and amplitude - the magnitude by which failed variables exceeded guidelines. The SQI calculation produces a numerical score with a maximum value of 100 representing the highest sediment quality. A modified SQI was also developed using only the scope and amplitude elements, which computed a score per site with no grouping. The SQI was applied to assessment of sediment quality in Lakes Erie and Ontario using Canadian Federal and Ontario Provincial guidelines for 34 compounds, Spatial trends in sediment quality in both lakes reflected overall trends for most individual contaminant classes, including mercury and polychlorinated biphenyls. In Lake Erie, there was a trend toward lower SQI values from the eastern basin to the western basin, and from the northern area to the southern area of the central basin. Sediment quality in the eastern basin and the northern area of the central basin was classified as excellent (>95); sediments in other areas of Lake Erie ranged from fair to good. In Lake Ontario, the poorest sediment quality was associated with the three major depositional basins; sediment quality among the three basins was quite consistent. The SQI values based on all three elements (scope, frequency and amplitude) for the Niagara basin. Mississauga Basin and Rochester Basin were 67 (fair), 65 (fair) and 70 (fair), respectively. Comparison of SQI values for all lower lake basins showed generally poorer sediment quality in Lake Ontario, compared to Lake Erie.  相似文献   

12.
Patterns of epilithic diatom species distribution in relation to environmental variables from 12 sampling sites on the main stream and some of its tributaries in the Nilüfer Stream Basin were determined using multivariate statistical techniques. The stream basin has been heavily influenced by anthropogenic effects. The upper part of the basin that is distant from pollution sources mostly has a spring water quality, while the lower part where the stream flows through the urban area and receives domestic and industrial wastewater has a quite low quality. Ordination techniques using both diatom taxa and 21 environmental variables revealed non- to slightly polluted upper basin sites and highly polluted lower basin sites along the stream. The results showed that the stream catchment is polluted gradually from upstream to downstream and that most of the downstream sites have very low water quality especially in summer months. A total of 134 epilithic diatom taxa belonging to 50 genera were recorded for 12 sample sites. Partial CCA results indicated that water temperature (T), discharge (Q), and total phosphorus (TP) were the most important variables affecting the distribution of diatom species. Unpolluted or slightly polluted upper basin sites were dominated by Achnanthidium minutissimum, Cocconeis placentula var. euglypta, Gomphonema olivaceum, and Navicula tripunctata. Highly polluted lower basin sites were characterized by high levels of organic and inorganic matters and low dissolved oxygen (DO) values. Species widespread in the highly polluted lower basin sites such as Nitzschia umbonata, Nitzschia amphibia, Nitzschia capitellata, Nitzschia palea, Nitzschia paleacea, Luticola mutica, and Stephanodiscus niagarae were mostly related to pollution indicator variables such as ammonium nitrogen (NH4 +–N), sodium (Na+), total phosphorus (TP), and total organic matter (TOM).  相似文献   

13.
Urban land use has been implicated as a major contributor of nonpoint source pollution in aquatic systems. Through increased nonpoint delivery of pollutants, including constituents found in stormwater, Lake Tahoe is undergoing a marked decline in its transparency, primarily due to increasing production of algae from enhanced nutrient loading and delivery of fine particles to the lake from the watershed. In response to these findings, a regional restoration effort is underway to improve basin watersheds and the water quality in Lake Tahoe. In this study, stormwater autosamplers were used to collect flow-weighted composite samples that characterized event mean concentrations for event and nonevent conditions within a small, urbanized watershed in the Tahoe basin. An event-specified constant-concentration water quality model was then applied to the event mean concentration and continuous streamflow data to estimate pollutant loads for nitrate, nitrite, ammonia, orthophosphate, and suspended sediment. These data were compared with previously reported load estimates from 10 primary monitored streams in larger watersheds of the Tahoe basin. Results from a linear regression analysis demonstrate strong and significant relationships between watershed impervious area and pollutant loadings from Lake Tahoe watersheds. These small, urbanized watersheds and intervening zones, which only comprise 10 % of the total Lake Tahoe drainage area, include a significant portion of the total Lake Tahoe impervious area. The findings of this study suggest that small, urbanized watersheds and intervening zones are disproportionately important contributors of nonpoint source pollution, including nutrients and suspended particles.  相似文献   

14.
A thorough investigation of the impact of rainbow trout (Oncorhynchus mykiss) cultivation on surface water quality in the area known as Bereket HES IV Dam Lake was conducted. Water samples were collected from October 2009 to June 2010 from four stations in the Dam Lake and analyzed for water temperature, pH, dissolved oxygen, electrical conductivity, nitrite nitrogen, nitrate nitrogen, and orthophosphate. Surface water quality was then evaluated based on the comparison of samples collected from three stations located near fish cages to those collected from a reference station outside the cultivation area as well as by the comparison with standards specified in the Water Pollution Registration Act. According to the Water Pollution Registration Act, the surface water quality of the Dam Lake was class I. Additionally, there were no significant differences in water quality within the Dam Lake among any of the sampling stations, including the reference station. Overall, these findings indicate that cage cultivation of rainbow trout may have a negative impact on the entire Dam Lake.  相似文献   

15.
以《湖北省水环境遥感监测示范系统》为数据处理平台,对2012—2014年湖北省大东湖水网、梁子湖水系和汤逊湖水系共计12个湖泊的水质类别以及营养状态级别进行遥感监测,并对比实测数据进行精度评价。结果表明:遥感监测的梁子湖、豹澥湖和严西湖水质相对较好,杨春湖、北湖和南湖水质相对较差且富营养化状况较为严重。该系统能很好地实现对水质优良达标湖泊以及富营养化湖泊的识别。对示范区域各湖泊水质类别和营养状态级别的遥感监测,基本上能满足业务化运行的需求。个别湖泊遥感监测精度较低,主要表现为遥感监测的湖泊水质类别和营养状态级别均要优于实测的结果。系统对于面积相对较大的湖泊遥感监测精度更高。  相似文献   

16.
Groundwater is the most important natural resource which cannot be optimally used and sustained unless its quality is properly assessed. In the present study, the spatial and temporal variations in physicochemical quality parameters of groundwater of Araniar River Basin, India were analyzed to determine its suitability for drinking purpose through development of drinking water quality index (DWQI) maps of the post- and pre-monsoon periods. The suitability for drinking purpose was evaluated by comparing the physicochemical parameters of groundwater in the study area with drinking water standards prescribed by the World Health Organization (WHO) and Bureau of Indian Standards (BIS). Interpretation of physicochemical data revealed that groundwater in the basin was slightly alkaline. The cations such as sodium (Na+) and potassium (K+) and anions such as bicarbonate (HCO3 ?) and chloride (Cl?) exceeded the permissible limits of drinking water standards (WHO and BIS) in certain pockets in the northeastern part of the basin during the pre-monsoon period. The higher total dissolved solids (TDS) concentration was observed in the northeastern part of the basin, and the parameters such as calcium (Ca2+), magnesium (Mg2+), sulfate (SO4 2?), nitrate (NO3 ?), and fluoride (F?) were within the limits in both the seasons. The hydrogeochemical evaluation of groundwater of the basin demonstrated with the Piper trilinear diagram indicated that the groundwater samples of the area were of Ca2+-Mg2+-Cl?-SO4 2?, Ca2+-Mg2+-HCO3 ? and Na+-K+-Cl?-SO4 2? types during the post-monsoon period and Ca2+-Mg2+-Cl?-SO4 2?, Na+-K+-Cl?-SO4 2? and Ca2+-Mg2+-HCO3 ? types during the pre-monsoon period. The DWQI maps for the basin revealed that 90.24 and 73.46 % of the basin area possess good quality drinking water during the post- and pre-monsoon seasons, respectively.  相似文献   

17.
随着太湖地区的经济发展及湖泊资源的利用,太湖水草的爆发性生长已经成为提高太湖水质、维持生态系统稳定的严重阻碍。水草枯亡后可能会导致水质异常,进而给苏州市饮用水安全带来威胁。依据4年来对太湖主要湖区水草的群落结构、分布范围、季节更替的研究,初步构建了太湖水草监管体系,为政府部门实施系统性监管提供支撑,并在全国湖泊水草监管方面发挥积极的示范作用。  相似文献   

18.
In 2010, a magnitude 7.0 earthquake struck Haiti, severely damaging the drinking and wastewater infrastructure and leaving millions homeless. Compounding this problem, the introduction of Vibrio cholerae resulted in a massive cholera outbreak that infected over 700,000 people and threatened the safety of Haiti’s drinking water. To mitigate this public health crisis, non-government organizations installed thousands of wells to provide communities with safe drinking water. However, despite increased access, Haiti currently lacks the monitoring capacity to assure the microbial safety of any of its water resources. For these reasons, this study was designed to assess the feasibility of using a simple, low-cost method to detect indicators of fecal contamination of drinking water that could be implemented at the community level. Water samples from 358 sources of drinking water in the Léogâne flood basin were screened with a commercially available hydrogen sulfide test and a standard membrane method for the enumeration of thermotolerant coliforms. When compared with the gold standard method, the hydrogen sulfide test had a sensitivity of 65 % and a specificity of 93 %. While the sensitivity of the assay increased at higher fecal coliform concentrations, it never exceeded 88 %, even with fecal coliform concentrations greater than 100 colony-forming units per 100 ml. While its simplicity makes the hydrogen sulfide test attractive for assessing water quality in low-resource settings, the low sensitivity raises concerns about its use as the sole indicator of the presence or absence of fecal coliforms in individual or community water sources.  相似文献   

19.
In this study, the characteristics, benefits, and effects of the environment and ecology project, which has been implemented in Turkey for the first time to restore the natural life that has been spoilt and the ecological balance of Lake Bafa located in Great Meander Basin, are searched. Moreover, the water samples taken from the stations that were spotted in the lake have been analyzed for the physical and chemical changes taking place in water quality before and after the project. The water cycle occurring as a result of giving water that was raised in Great Meander River by the Rubber regulator, which is the most important element of the project, through the Serçin inlet and feeder channel; and draining the saline and low-quality water to the river bed of the Great Meander, will improve the water quality, the natural life, and the ecological balance of the lake in time. Thanks to the water given to the lake within the scope of project, the salinity of the lake water decreased from 25,500 to 22,500 mmhos cm???1. The electrical conductivity, Na?+?, Mg?+?2, Ca?+?2, Cl???, $\text{CO}_\text{3} ^{-\text{2}}In this study, the characteristics, benefits, and effects of the environment and ecology project, which has been implemented in Turkey for the first time to restore the natural life that has been spoilt and the ecological balance of Lake Bafa located in Great Meander Basin, are searched. Moreover, the water samples taken from the stations that were spotted in the lake have been analyzed for the physical and chemical changes taking place in water quality before and after the project. The water cycle occurring as a result of giving water that was raised in Great Meander River by the Rubber regulator, which is the most important element of the project, through the Ser?in inlet and feeder channel; and draining the saline and low-quality water to the river bed of the Great Meander, will improve the water quality, the natural life, and the ecological balance of the lake in time. Thanks to the water given to the lake within the scope of project, the salinity of the lake water decreased from 25,500 to 22,500 mmhos cm( - 1). The electrical conductivity, Na+, Mg+2, Ca+2, Cl(-), CO3(-2), HCO3(-), and the amount of the organic substances were found as over the appropriate values for fishery. Besides, the decreases in the amounts of NO3(-), HN3(-) and PO4(-3) affect the living beings in the lake negatively. In addition, the measures to take are specified, so that the natural life of the Lake and the ecological balance can renew themselves within a short time.  相似文献   

20.
阳澄湖是太湖平原上第三大淡水湖泊和苏州市重要的综合水源.从2004年3-10月对阳澄湖进行了3次浮游植物的调查,共发现浮游植物8门83属211种(包括变种),其中阳澄西湖71属153种、阳澄中湖68属140种、阳澄东湖74属151种.并利用浮游植物的生物学多样性指数对阳澄湖进行了水质评价,该水体整体处于重污染状态,且污...  相似文献   

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