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1.
Lichen transplants of Hypogymnia physodes were used in a high-density network of sites for collecting airborne metals from the atmosphere in Armadale, a small industrial town in central Scotland. The mapping of the concentrations of various metals revealed a gradient of metal values which decreased outwards from the town's steel foundry. The findings were discussed in the context of a previous epidemiological investigation of lung disease in the town.  相似文献   

2.
This aim of this monitoring was to assess water quality in a dry season for the Cape Coast municipality in Ghana, which has been experiencing chronic water shortages. Fifteen different sampling stations—four surface, five ground, and six tap water samples—were analyzed for physicochemical and microbiological parameters during January to April 2005. Levels or trends in water quality that may be deleterious to sensitive water uses, including drinking, irrigation, and livestock watering have been noted with reference to well-established guidelines. Exceedances to some health-based drinking water guidelines included positive coliform for various water samples; pH for all groundwater samples (pH 5.9 ± 0.3); conductivity for 50% groundwater; color for about a third of groundwater and tap water; Mn for 44% tap water, 67% groundwater, and 50% surface water samples. The World Health Organization laundry staining Fe guideline of 0.3 mg/l was exceeded by 75% of surface water, 44% tap water, and 53% groundwater samples. The corresponding Mn guideline of 0.1 mg/l was exceeded by all the water samples. Respectively, all surface water samples and also 75% of the surface water exceeded some known Cu and Zn guideline for the protection of aquatic life. Compared to some historic data for Fosu Lagoon, the current study shows a lowering of ~1 pH unit, increase of ~65% $\text{NH}_{3}$ , one to two orders of magnitude increase in PO $_{4}^{{3}^{-}}$ , and more than two orders of magnitude increase in NO $_{3}^{-}$ . In several instances, tap water samples collected at the consumers’ end of the distribution system did not reflect on the true quality of the treated water. Mn, SO $_{4}^{{2}^{-}}$ , PO $_{4}^{{3}^{-}}$ , Cu, and Zn were among the chemical contaminations observed to occur in the distribution system.  相似文献   

3.
The occurrence of As was studied in groundwater used for human consumption and irrigation, in stream water and sediments and in water from thermal springs in the drainage basin of Kalloni Gulf, island of Lesvos, Greece, in order to investigate the potential influence of the geothermal field of Polichnitos-Lisvori on the ground and surface water systems of the area. Total dissolved As varied in the range <0.7-88.3 microg L(-1) in groundwater, 41.1-90.7 microg L(-1) in thermal spring water and 0.4-13.2 microg L(-1) in stream water, whereas As concentrations in stream sediments varied between 2.0-21.9 mg kg(-1). Four out of 31 groundwater samples exceeded the EC standard of 10 microg L(-1). The survey revealed an enrichment in both surface and groundwater hydrological systems in the northern part of the area (average concentrations of As in groundwater, stream water and stream sediment: 8.0 microg L(-1), 8.8 microg L(-1) and 15.0 mg kg(-1) respectively), in association with the volcanic bedrocks, while lower As concentrations were found in the eastern part (average concentrations in groundwater, stream water and stream sediment: 2.9 microg L(-1), 1.7 microg L(-1) and 5.9 mg kg(-1) respectively), which is dominated by ophiolitic ultramafic formations. The variation of As levels between the different parts of the study area suggests that local geology exerts a determinant influence on As geochemical behaviour. On the other hand, the geothermal activity manifested in the area of Polichnitos-Lisvori does not affect the presence of As in groundwater and streams.  相似文献   

4.
Hourly concentrations of ozone (O(3)), 55 volatile organic compounds (VOCs, ozone precursors) and nitrogen oxides (NOx) were measured at an upwind urban site, a downwind suburban site, and a rural site in central Taiwan, from January 2003 to December 2006. VOC and NOx mean concentrations showed a gradient from high to low across the urban (56 ppb and 34 ppb), suburban (38 ppb and 27 ppb) and rural sites (25 ppb and 21 ppb) but a reverse gradient in ozone across these sites (24, 27, and 29 ppb, respectively). Although there was about twice the difference in VOC concentrations between the urban and rural sites, nearly 65% ozone formation potential was contributed to by the same 9 VOCs. Seasonal patterns showed peak ozone levels in autumn and minima in summer at the urban site, but minima in winter at the downwind suburban and rural sites. Ozone precursor levels, on the other hand, were lowest in summer and highest in winter. The diurnal pattern showed that ozone levels peaked one hour later at the rural site than at the urban site. The ethylbenzene to m,p-xylene ratio, an indicator of the age of the air mass, increased from 0.4 at the urban site to 0.6 at the suburban site and 0.8 at the rural site during daily peak ozone times. This finding suggests the transport of ozone and precursors from upwind to downwind producing elevated ozone levels in the suburban and rural areas. Ozone episodes occurred mostly in days with a mean midday UV index of 6.5 (1 UV index=100 J m(-2)) and wind speed at 1.3 m s(-1) at all three sites.  相似文献   

5.
6.
In this paper, we discuss the advantages and drawbacks of POCIS (Polar Organic Chemical Integrative Sampler) for the evaluation of river water quality downstream of wastewater treatment plants. POCIS proved well adapted to sampling alkylphenols and several pharmaceuticals. Concentration factors and the decrease in limits of quantification, compared to grab water sample analyses, were significant except for hormones, β-blockers and bronchodilators. Promising preliminary results obtained in situ on deuterated atenolol used as a performance reference compound need to be confirmed in-lab. This work confirms that POCIS is a valuable tool for monitoring hydrophilic organic molecules in river and wastewaters.  相似文献   

7.
In recent years, the Taiwanese government has strongly promoted the concept of ecological engineering in the hope that doing so will encourage the maintenance of the ecosystem and its integrity. As a result, the riprap spur dike is one of the most commonly used measures for protecting stream banks. Traditionally, a spur dike is used at concave banks to prevent their scouring and/or to increase their stabilization. An additional benefit of deflector structures, like spur dikes, may be to increase the weighted usable area (WUA) for aquatic life survival during periods of increased flow (examples include typhoon, flood, etc.). A two-dimensional river habitat simulation program (River2D) coupled with a developed shallow water habitat type diversity module was used for the case study at a headwater stream in central Taiwan. The habitat suitability index for this study was established using substrate, depth, and velocity from field surveys for the fish family Cyprinidae by prepositioned area electrofisher. The ungauged flood conditions were calculated using digital elevation models within a watershed delineation and hydrological modeling system in accordance with local regulations. Simulated results indicate that the spur dikes currently in use on the stream in this study need be improved from a WUA point of view more effectively handle a flood event.  相似文献   

8.
Water quality impairment by fecal waste in coastal watersheds is a public health issue. The present study provided evidence for the use of a mitochondrial (mtDNA) marker to detect animal fecal sources in surface water. The accurate identification of fecal pollution is based on the notion that fecal microorganisms preferentially inhabit a host animal’s gut environment. In contrast, mtDNA host-specific markers are inherent to eukaryotic host cells, which offers the advantage by detecting DNA from the host rather than its fecal bacteria. The present study focused on sampling water presumably from non-point sources (NPS), which can increase bacterial and nitrogen concentrations to receiving water bodies. Stream sampling sites located within the Piscataqua River Watershed (PRW), New Hampshire, USA, were sampled from a range of sites that experienced nitrogen inputs such as sewer and septic systems and suburban runoff. Three mitochondrial (mtDNA) gene marker assays (human, bovine, and canine) were tested from surface water. Nineteen sites were sampled during an 18-month period. Analyses of the combined single and multiplex assay results showed that the proportion of occurrence was highest for bovine (15.6%; n = 77) compared to canine (5.6%; n = 70) and human (5.7%; n = 107) mtDNA gene markers. For the human mtDNA marker, there was a statistically significant relationship between presence vs. absence and land use (Fisher’s test p = 0.0031). This result was evident particularly for rural suburban septic, which showed the highest proportion of presence (19.2%) compared to the urban sewered (3.3%), suburban sewered (0%), and agricultural (0%) as well as forested septic (0%) sites. Although further testing across varied land use is needed, our study provides evidence for using the mtDNA marker in large watersheds.  相似文献   

9.
The catastrophic earthquake, 7.3 on the Richter scale, occurred on September 21, 1999 in Central Taiwan. Much of standing vegetation on slopes was eliminated and massive, scattered landslides were induced at the Jou-Jou Mountain area of the Wu-Chi basin in Nantou County. We evaluated three methods for assessing landslide hazard and vegetation recovery conditions. (1) Self-organizing map (SOM) neural network coupled with fuzzy technique was used to quickly extract the landslide. (2) The NDVI-based vegetation recovery index derived from multi-temporal SPOT satellite images was used to evaluate vegetation recovery rate in the denudation sites. (3) The spatial distribution index (SDI) based on land-cover topographic location was employed to analyze vegetation recovery patterns, including the invading, surviving and mixed patterns at the Jou-Jou Mountain area. On September 27, 1999, there were 849.20 ha of landslide area extracted using the self-organizing map and fuzzy technique combined model. After six years of natural vegetation succession, the landslide has gradually restored, and vegetation recovery rate reached up to 86%. On-site observation shows that many native pioneer plants have invaded onto the denudation sites even if disturbed by several typhoons. Two native surviving plants, Arundo formosana Hack and Pinus taiwanensis Hayata, play a vital role in natural vegetation succession in this area, especially for the sites on ridgeline and steep slopes.  相似文献   

10.
The surface water quality of the Euphrates river basin in Turkey are evaluated by using the multivariate statistical techniques known as factor analysis (FA) and multidimensional scaling (MDS) analysis. When FA was applied to the water quality data obtained from the 15 different surface water quality monitoring stations, two factors were identified, which were responsible from the 86.02% of the total variance of the water quality in the Euphrates river basin. The first factor called the urban land use factor explained 44.20% of the total variance and the second factor called the agricultural use factor explained 41.81% of the total variance. MDS technique showed that electrical conductivity (EC), percent sodium (Na%) and total salt are the most important variables causing difference in the water quality analysis.  相似文献   

11.
Multivariate statistical techniques, such as cluster analysis (CA), principal component analysis, and factor analysis, were applied for the evaluation of temporal/spatial variations and for the interpretation of a water quality data set of the Behrimaz Stream, obtained during 1 year of monitoring of 20 parameters at four different sites. Hierarchical CA grouped 12 months into two periods (the first and second periods) and classified four monitoring sites into two groups (group A and group B), i.e., relatively less polluted (LP) and medium polluted (MP) sites, based on similarities of water quality characteristics. Factor analysis/principal component analysis, applied to the data sets of the two different groups obtained from cluster analysis, resulted in five latent factors amounting to 88.32% and 88.93% of the total variance in water quality data sets of LP and MP areas, respectively. Varifactors obtained from factor analysis indicate that the parameters responsible for water quality variations are mainly related to discharge, temperature, and soluble minerals (natural) and nutrients (nonpoint sources: agricultural activities) in relatively less polluted areas; and organic pollution (point source: domestic wastewater) and nutrients (nonpoint sources: agricultural activities and surface runoff from villages) in medium polluted areas in the basin. Thus, this study illustrates the utility of multivariate statistical techniques for analysis and interpretation of data sets and, in water quality assessment, identification of pollution sources/factors and understanding temporal/spatial variations in water quality for effective stream water quality management.  相似文献   

12.
In this study, a questionnaire survey of school drinking water quality of 42 schools in Pingtung County was conducted according to the water sources, treatment facilities, location of school as well as different grade levels. Among them, 45% of schools used tap water as the main source of drinking water, and the schools using groundwater and surface water as drinking water source account for 29% and 26%, respectively. The schools above senior high school level in the city used tap water as drinking water more than underground water, while the schools under junior high school level in the rural area used surface water as their main source of drinking water. The surface water was normally boiled before being provided to their students. The reverse osmosis system is a commonly used water treatment equipment for those schools using tap water or underground water. Drinking fountain or boiled water unit is widely installed in schools above senior high school level. For schools under junior high school level, a pipeline is stretched across the campus. Relative test shows that the unqualified rate of microbe in water is 26.2%. All parameters for physical and chemical properties and metal content had met the domestic standards except that the turbidity of schools under junior high school level using tap water is slightly higher than the standard value.  相似文献   

13.
In the study, discriminant analysis (DA) was applied to water quality data set monitored in winter and summer months along 3 years to investigate seasonal variations of Tahtali Reservoir water quality. The variables were divided into two categories as “parameters naturally found in surface waters—Al, Fe, Mn, F, Ba, Cl, and SO4” and “pollutants—biochemical oxygen demand, chemical oxygen demand, and NO3”. Linear discriminant functions were calculated to distinguish between winter and summer samples. Results revealed that water quality variables (naturally found in surface water and also pollutants) were distinctly different between two seasons. Seasonal changes of water quality caused by anthropogenic activities should be taken into consideration by the water managers especially in summer seasons in which higher concentrations were observed. The study showed that DA can be applied successfully to establish the seasonal variation in surface water quality and make it possible to design a future temporal sampling strategy in an optimal manner.  相似文献   

14.
In Yangmingshan National Park, located in the northern part of the Taiwan Island, there is a very rare area where fish (Channa asiatica) live in spite of acid environments. The origin of the acid in local acid ponds and rivers and the evolution of the water chemistry are discussed on the basis of sulfur stable isotope ratios and chemical equilibria. One of the sources of the acid is sulfuric acid, which is derived from the oxidation of hydrogen sulfide in volcanic gas gushing out from fumaroles around the area and from acid deposition supplied from Taipei City. It is also derived from the oxidation of pyrite: the sulfur stable isotope ratios of delta 34S of +1@1000 to +4@1000 (relative to CDT) of sulfate in acid pond waters (pH 3-4) could be related to those of hydrogen sulfide in volcanic gas, pyrite in local pond sediments and soils, and sulfate in rain water. One acid source is sulfuric and hydrochloric acids arising in springs from geothermal activity: the delta 34S values were characterised by +13@1000 to +17@1000 sulfate-S, which was provided by a disproportionation reaction of sulfur dioxide in the depths. Another acid source could be the oxidation of iron(II). Under acidic conditions, the water-rock reaction gives rise to high concentrations of aluminium and iron. While flowing down surface streams, iron(II) is oxidised to iron(III) and then hydrolysed to cause further acidification under oxic conditions. The concentrations of iron and aluminium are controlled by redox and dissolution equilibria.  相似文献   

15.
In the study, multivariate statistical methods including factor, principal component and cluster analysis were applied to analyze surface water quality data sets obtained from Xiangjiang watershed, and generated during 7 years (1994-2000) monitoring of 12 parameters at 34 different profiles. Hierarchical cluster analysis grouped 34 sampling sites into three clusters, including relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) sites, and based on the similarity of water quality characteristics, the watershed was divided into three zones. Factor analysis/principal component analysis, applied to analyze the data sets of the three different groups obtained from cluster analysis, resulted in four latent factors accounting for 71.62%, 71.77% and 72.01% of the total variance in water quality data sets of LP, MP and HP areas, respectively. The PCs obtained from factor analysis indicate that the parameters for water quality variations are mainly related to dissolve heavy metals. Thus, these methods are believed to be valuable to help water resources managers understand complex nature of water quality issues and determine the priorities to improve water quality.  相似文献   

16.
A new HPLC method was developed for the simultaneous determination of aminophenol isomers by means of a mixed-mode stationary phase containing both SCX and C18 moieties. All factors influencing the separation were discussed and optimized. The chromatographic conditions for the separation of aminophenols are the stationary phase duet SCX/C18, the mobile phase of aqueous phosphate buffer (pH 4.85):methanol?=?85:15 (v/v) delivered with a flow rate of 1 mL/min and a detection at 285 nm. The method proposed was validated in terms of linearity, limits of detection and quantification, accuracy and precision. The HPLC method elaborated here was applied with good results on river water samples. In order to survey the quality of surface rivers entered in treatment plants which deliver water for Bucharest, two major rivers were included in a monitoring program which last more than 1 year.  相似文献   

17.
High selenium (Se) concentrations have been found in surface waters in the Kendrick Reclamation Project, Wyoming. Precipitation and irrigation water moving over seleniferous soils are contributing causes, and drought may exacerbate this. This study surveyed Se concentrations and discharges in local surface streams, irrigation drains, and the delivery canal. Sites were sampled monthly and analyzed for Se and total suspended solids (TSS). A completely randomized design with two factors (soil parent material and location, inside or outside irrigation district) was used. Mean Se concentrations were 64 μg L???1 inside the irrigation district on shale soils, 17 μg L???1 inside the district off shale soils, 5 μg L???1 outside the district on shale soils, and 3 μg L???1 outside the district off shale soils. Correlations between discharge and Se concentrations were generally negative, while correlations between discharge and Se load were generally positive. There was little correlation between load and concentration, and little correlation between TSS and Se. A comparison of Se concentrations in streams and drains showed Se concentrations were significantly higher (p?<?0.001) in streams during the irrigation season, but not in the off-season (p?=?0.515). We conclude that higher discharges decrease Se concentration, but increase load. Conversion from flood to sprinkle irrigation may increase Se concentrations by reducing discharge, but decrease Se loads going into the N. Platte River, and will likely alter the timing and magnitude of flows. Both load and concentration should be considered when implementing Se regulations and standards.  相似文献   

18.
Surface data of meteorological parameters (wind speed, wind direction, and mixing height) and air pollutant concentrations (O3, NO, and NO2) were collected for a 92-day period associated with typhoon formation in 2005. The influence of typhoons on O3 concentration were defined by azimuth and distance from Taiwan, and Types A, B, and C correspond to typhoons less than 1,500 km from Taiwan and located between azimuths 45° and 135°, 135° and 225°, and 225° and 45°, respectively. Type D corresponds to typhoons more than 1,500 km from Taiwan. Titration reactions were conducted at three temporal phases: 2000–0700, 0800–1100, and 1200–1400 LST (Local Standard Time). The air pollution model (TAPM) was used to simulate wind fields and trajectories of air masses. It was determined that typhoon position affected O3 concentration, temporal and spatial patterns of O3 titration and vertical meteorological characteristics, which were not all at the statistically significant level.  相似文献   

19.
Dry deposition samples collected during 1999–2001 at a South China site using surrogate surfaces were analyzed by capillary electrophoresis. Collector surface properties played important roles to the dry deposition. The deposition velocities for various species ranged from 0.02 to 1.69 cm s???1, in general agreement with literature values. More than 90% of Ca2?+? was deposited by sedimentation and its comparable values of dry or wet removal residence times imply that dry deposition is an important atmospheric removal process for the ubiquitous crustal species in South China, compared with precipitation scavenging. Relatively good agreement was found when the species deposition velocities were modeled based on up-to-date knowledge of particle dry deposition. The total depositions for anthropogenic and crustal species in northern China are likely to be much higher than those in the south, including our site where the fluxes of the acidic species SO4 2??? and NO3 ??? were 4.4 and 2.2 g m???2 year???1, respectively. The sum of dry deposition for cations Na?+?, Ca2?+?, Mg2?+?, and K?+? contributes 44% of the total flux, which is equivalent to the value estimated in Europe.  相似文献   

20.
The analysis of a large number of multidimensional surface water monitoring data for extracting potential information plays an important role in water quality management. In this study, growing hierarchical self-organizing map (GHSOM) was applied to a water quality assessment of the Songhua River Basin in China using 22 water quality parameters monitored monthly from 13 monitoring sites from 2011 to 2015 (14,782 observations). The spatial and temporal features and correlation between the water quality parameters were explored, and the major contaminants were identified. The results showed that the downstream of the Second Songhua River had the worst water quality of the Songhua River Basin. The upstream and midstream of Nenjiang River and the Second Songhua River had the best. The major contaminants of the Songhua River were chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total phosphorus (TP), and fecal coliform (FC). In the Songhua River, the water pollution at downstream has been gradually eased in years. However, FC and biochemical oxygen demand (BOD5) showed growth over time. The component planes showed that three sets of parameters had positive correlations with each other. GHSOM was found to have advantages over self-organizing maps and hierarchical clustering analysis as follows: (1) automatically generating the necessary neurons, (2) intuitively exhibiting the hierarchical inheritance relationship between the original data, and (3) depicting the boundaries of the classification much more clearly. Therefore, the application of GHSOM in water quality assessments, especially with large amounts of monitoring data, enables the extraction of more information and provides strong support for water quality management.  相似文献   

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