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1.
In modern civilization, numerous anthropogenic activities release a variety of pollutants into the environment and with anomalous enrichment of heavy metals it causes surface and subsurface contamination. The aquatic sediments provide pertinent tools for the quality assessment of urban and industrial environments in large cities. The present study reveals short-term accumulative trends of heavy metals (Co, Cd, and Pb) in the sand and silt dominated riverbed sediments from Chitgar industrial area (Tehran, Iran) between the period of May 2007 and May 2008. Lead demonstrates highest concentration in residential areas, cadmium in and around industrial areas, whereas cobalt shows least variability. Geo-accumulation index implies moderately to highly polluted sediments with respect to Cd and Pb. With few exceptions, all three metals at different sampling stations display short-term increasing trends, independent of seasonal variability with urban and industrial distends along the river being the chief sources of contamination.  相似文献   

2.
The present study deals with the characterization of industrial effluents released from various industries and distribution of heavy metals in effluent discharge channel and its impact on the river Damodar. The effluent of tamlanala, a natural storm water channel, is extensively used for irrigation for growing vegetables in and around the study area. The heavy metals in water of the study area are in the order of Fe > Mn > Pb >?Cd and sediments follow similar trends too. The enrichment of heavy metals in the sediments are in the order of Cd (39.904) > Pb (33.156) > Mn (0.164) > Fe (0.013). The geoaccumulation index values reveal effluent channel is subjected to moderate to high pollution with respect to Cd (4.733) and Pb (4.466). The analyzed data for enrichment factors and the pollution load index (1.305) show that effluent channels have suffered from significant heavy metal contamination following industrialization and urbanization. Compared to baseline values, the surface sediment layers show high enrichment across the channel and at its discharge point. The factor analysis reveals three factors—industrial sources, surface runoff inputs, and background lithogenic factors which clarify the observed variance of the environmental variables. Metal pollution assessment of sediments suggests that pollution from the heavy metals observed is high in the tamlanala which in turn affects the downstream of the river system.  相似文献   

3.
Despite the numerous benefits of hydropower production, this renewable energy source can have serious negative consequences on the environment. For example, dams act as barriers for the longitudinal migration of organisms and transport of particulate matter. Accelerated siltation processes in the receiving river reduce the vertical connectivity between river and groundwater. Hydropeaks, caused by short-term changes in hydropower operation, result in a negative impact on both habitat and organisms, especially during winter months when natural discharge is low and almost constant. In this study, we report the current deficits present in the River Rhone from two different scientific perspectives – fish ecology and hydrology. Potential rehabilitation solutions in synergy with flood protection measures are discussed. We focus on the effects of hydropeaking in relation to longitudinal and vertical dimensions and discuss local river widening as a potential rehabilitation tool. The fish fauna in the Rhone is characterized by a highly unnatural structure (low diversity, impaired age distribution). A high correlation between fish biomass and monotonous morphology (poor cover availability) was established. Tracer hydrology provided further details about the reduced permeability of the riverbank, revealing a high degree of siltation with K values of about 4.7 × 10?6 m s?1. Improving the hydrologic situation is therefore essential for the successful rehabilitation of the Rhone River. To this end, hydropeaks in the river reaches must be attenuated. This can be realized by a combination of different hard technical and soft operational measures such as retention reservoirs or slower up and down ramping of turbines.  相似文献   

4.
This study is carried out to evaluate potentially toxic metal concentrations (As, Cd, Cr, Cu, Hg, Mo, Ni, Pb, and Zn) together with their spatial distribution, degree of pollution, and potential ecological risk in Kor river sediments (southwest Iran) using sediment quality guidelines, geoaccumulation index (I geo), Hakanson potential ecological risk index (RI), and standard methods of statistical analysis. The study area stretches some 140 km from the Drodzan Dam to Bakhtegan Lake, a stretch of river where different industrial and domestic activities (e.g., petrochemical complex, oil refinery, industrial meat processing complex, Marvdasht city sewage) and ecological value overlap with each other. Calculated geoaccumulation index indicate that 50 % of the stations are moderately to very extremely polluted. The potential ecological risk for nine investigated metals in Kor river is Hg (948)?>?Mo (51.9)?>?Ni (37.8)?>?Cd (29.8)?>?As (22)?>?Cu (16.6)?>?Pb (13.3)?>?Zn (3.3)?>?Cr (1). Results show that sediments in parts of Kor river sediments are heavily affected by effluents discharged from industrial plants and other parts are affected by agriculture and urban runoff from nearby lands. These phenomena may cause a risk of secondary water pollution under sediment disturbance and/or changes in the physical–chemical characteristics of the aquatic system.  相似文献   

5.
The mutagenic activity of XAD-2 adsorbates and water extracts recovered from nine locations of the Kumho River was tested on S. typhimurium TA98 strain to identify the source of the mutagenicity. A sampling site, receiving effluents from the textile industrial complex located in Daegu City, showed extraordinarily high mutagenic activity, especially in the presence of S9 mixture, at all sampling time in both XAD-2 adsorbates and dichloromethane extracts. This indicated the existence of the frame-shift mutagens in the Kumho River, same type of mutagens detected in previous studies by other researchers in the Nakdong River into which the Kumho River discharges. The fractionation study showed that the mutagenic chemicals in the river water are mid-polar. Furthermore, mean tail length obtained by single cell gel electrophoresis assay (Comet assay) showed consistent dose-dependent DNA damage, indicating that the chemicals in the river water not only act as frame-shift mutagens but also break human lymphocytes DNA strain. Chemical identification of the mutagens should be required.  相似文献   

6.
In this study an assessment is made of the negative impacts of wastewater irrigation on soils and crops sampled along the Khoshk River channel in suburban area of Shiraz City, SW Iran. For this purpose, samples of soil profiles (0–60 cm in depth) and crops were collected from two wastewater irrigated sites and a tube well-irrigated (control) site. Total concentrations of the five heavy metals (Ni, Pb, Cd, Zn and Cr) and their phytoavailable contents were determined. The Pollution Load Indexes (PLIs) and Contamination Factors (CFs) for soils and Hazard quotients (ΣHQ) for some vegetables were also calculated. The results showed the use of untreated wastewater has caused the following changes as compared to control site: (1) a 20–30% increase in organic matter content of soil; (2) increase in pH by 2–3 units; (3) significant concentration increase in Ex-Ca especially in top layers of soil resulting in high CEC; (4) build up of heavy metals (notably Pb and Ni) in topsoil above Maximum Permissible Limits (MPLs) indicating a moderate contamination (PLI > 1, CF > 2.5); (5) contamination of some vegetables (spinach and lettuce) with Cd due to its high phytoavailability in topsoil causing a HQ > 1; (6) excessive accumulation of Ni and Pb in wheat due to continual addition of heavy metals through long-term wastewater application. The study concludes that strict protection measures, stringent guidelines and an integrated system for the treatment and recycling of wastewater are needed to minimize the negative impacts of wastewater irrigation in the study area.  相似文献   

7.
The Thirumanimuttar sub-basin forms an important groundwater province in south India, facing serious deficiency in both quality and quantity of groundwater due to increased demand associated with rapid population explosion, agricultural growth and industrial activities. A total of 194 groundwater samples were collected and 15 water quality parameters were analyzed using standard procedures. Na + , Cl − , Ca2 + , HCO3-_{3}^{-}, Mg2 +  and SO42-_{4}^{2-} concentration ions are more dominant in both seasons. The total dissolved solids and electrical conductivity was observed good correlation with Na + , Cl − , HCO3-_{3}^{-}, Ca2 + , Mg2 + , Cl − , PO43-_{4}^{3-} and NO3- _{3}^{- } ions indicating dominance of plagioclase feldspar weathering, anthropogenic input and over drafting of groundwater irrespective of seasons. The Hill–Piper diagram indicates alkaline earths exceed the alkalis, an increase of weak acids was noted during both the seasons. For assessing the groundwater for irrigation suitability parameters like total hardness, sodium adsorption ratio, residual sodium carbonate (RSC), permeability index, and sodium percentage are also calculated. Permanent hardness was noted in higher during both the seasons due to discharge of untreated effluents and ion exchange process. The RSC indicates 56% of the samples are not suitable for irrigation purposes in both seasons, if continuously used will affect the crop yield. From the results, nearly 72% of the samples are not suitable for irrigation.  相似文献   

8.
Heavy metal contents and contamination characteristics of the water and sediment of the Khoshk River, Shiraz, Southwest Iran were investigated. The abundance of heavy metals decreases as Zn > Mn > Cr > Ni >Pb > Cu > Cd in water samples and Mn > Cr > Pb > Ni > Zn > Cu > Cd in sediments, respectively. Based on the enrichment factor and geoaccumulation index values, sediments were loaded with Cr, Zn, Pb, Cu, and Cd. Pearson correlation matrix as well as cluster and principal components analyses and analysis of variance were implemented on data from sampling sites. Based on the locations of sampling sites in clusters and variable concentrations at these stations, it was concluded that municipal, industrial, and domestic discharges in the Shiraz urban area strongly affected heavy metals concentrations in the Khoshk River water and sediment. Results obtained from principal components analysis of sediment samples showed that the high concentration of Ni was mainly from natural origin, related to the composition of parent rocks, while the elevated values of Cr, Zn, Pb, Cd, and Cu were due to anthropogenic activities.  相似文献   

9.
10.
Spontaneous combustion on industrial-scale stockpiles causes environmental problems and economic losses for the companies consuming large amounts of coal. In this study, an effective monitoring and prediction system based on internet was developed and implemented to prevent losses and environmental problems. The system was performed in a coal stockpile with 5 m width, 10 m length, 3 m height, and having 120 t of weight. The inner temperature data of the stockpile was recorded by 17 temperature sensors placed inside the stockpile at certain points. Additionally, the data relating to the air temperature, air humidity, atmospheric pressure, wind velocity, and wind direction that are the parameters affecting the coal stockpile were also recorded. The recorded values were analyzed with artificial neural network and Statistical modeling methods for prediction of spontaneous combustion. Real-time measurement values and model outputs were published with a web page on internet. The internet-based system can also provide real-time monitoring (combustion alarms, system status) and tele-controlling (Parameter adjusting, system control) through internet exclusively with a standard web browser without the need of any additional software.  相似文献   

11.
We assessed the impact of urban effluents on the concentrations of selected minerals (Cd, Cr, Cu, Fe, Pb, Zn, Mn, Ni, and Hg) in river Ravi before and after its passage through Lahore city. Water and sediment samples were collected from three lowly to highly polluted downstream sites (Shahdera (B), Sunder (C), and Balloki (D)) alongside the least polluted upstream site (Siphon (A)) during high and low river flow seasons. All the mineral concentrations increased up to site C but stabilized at site D, showing some recovery as compared to the third sampling site. The trend of mean mineral concentration was significantly higher during the low than the high flow season at all the sites. The mean Hg concentrations approached 0.14 and 0.12 mg/l at site A which increased (%) up to 107 and 25 % at site B, 1,700 and 1,317 % at site C, and 1,185 and 1,177 % at site D during low and high river flows, respectively. All mineral concentrations were much higher in the sediment than the water samples. Mean Cd (917 %), Cr (461 %), Cu (300 %), Fe (254 %), Pb (179 %), Zn (170 %), Mn (723 %), Ni (853 %), and Hg (1,699 %) concentrations were higher in riverbed sediments sampled from site C in comparison with the sample collected at site A during low flow season. The domestic and industrial discharges from Lahore city have created undesirable water qualities during the low river flow season. As majority of the mineral levels in the river Ravi were higher than the permissible and safe levels, this is of immediate concern for riverine fish consumers and the users of water for recreation and even irrigation. The use of these waters may pose health risks, and therefore, urgent intervention strategies are needed to minimize river water pollution and its impact on fish-consuming communities of this study area and beyond.  相似文献   

12.
13.
Concentrations of heavy metals (Cu, Cr, Fe, Pb, Zn, Hg, Ni, and Cd) and macronutrients (Mn) were measured in industrial effluents, water, bottom sediments, and wetland plants from a reservoir, Govind Ballabh (G.B.) Pant Sagar, in Singrauli Industrial region, India. The discharge point of a thermal power plant, a coal mine, and chlor-alkali effluent into the G.B. Pant Sagar were selected as sampling sites with one reference site in order to compare the findings. The concentrations of heavy metals in filtered water, sieved sediment samples (0.4-63 microm), and wetland plants were determined with particle-induced X-ray emission. The collected plants were Aponogeton natans, L. Engl. & Krause, Cyperus rotundus, L., Hydrilla verticillata, (L.f.) Royle, Ipomoea aquatica, Forssk., Marsilea quadrifolia, L., Potamogeton pectinatus, L., Eichhornia crassipes, (Mart.) Solms Monogr., Lemna minor, L., Spirodela polyrhiza (L.) Schleid. Linnaea, Azolla pinnata, R.Br., Vallisneria spiralis, L., and Polygonum amphibium, L. In general, metal concentration showed a significant positive correlation between industrial effluent, lake water, and lake sediment (p < 0.01). Likewise, significant positive correlation was recorded with metals concentration in plants and lake ambient, which further indicated the potential of aforesaid set of wetland macrophytes for pollution monitoring.  相似文献   

14.
The shipbuilding industry of Korea, ranked number one in the world in annual amount of ship orders, has contributed to national economic growth; however, this has resulted in various environmental problems. Characteristics of environmental pollution, such as particulate matters, odor, and noise, which are closely related with public complaints, were evaluated in an industrial shipbuilding complex. The concentrations of PM-10 and TSP were significantly affected by the distance between the measurement site and shipbuilding workplace, as well as the height of the measurement site. Average PM-10 concentrations in the residential area ranged from 40.10 to 44.10 ??g/m3, which were not high in comparison with the ambient air quality standard and those of major cities in Korea. Paint particles could affect a wider area than typical particulate matters due to their generation and transport properties. The properties of odor in the study area were widely affected by the work intensity in shipyards and the temperature. Twenty-five out of total 54 samples collected in the residential area exceeded the dilution factor of 10, which is the tolerable limit adopted in Korea. Noise had an influence on a limited area due to the extinction effect with distance from the shipyards, while severe noise levels higher than 90 dB(A) were frequently found inside the shipyards.  相似文献   

15.
The influence of visitors on macroinvertebrates of rocky intertidal shores was investigated in southern coasts of the Qeshm Island, the Persian Gulf, Iran. Qeshm Island located at the Strait of Hormuz, with an area of 1,491 km2, is the largest island in the region. This island consists of a number of important natural habitat types including creeks, mangroves, corals, and sandy, muddy, and rocky shores that accommodate diverse marine flora and fauna communities. Two rocky shores were selected at the touristic beaches being visited regularly, and further two control locations selected at pristine shores. Intertidal macroinvertebrates were collected from six microhabitats including rock platforms, cobbles, boulders, crevices, sea walls, and rock pools during two different periods representing high and low tourist seasons. Species richness, density, and assemblage structure in heavily visited shores were compared with that of control locations. Striped barnacles (Balanus amphitrite) were present on platforms of all locations, thus the changes in their size were used as the obvious contrast associated with visitor’s impact. A total of 70 macroinvertebrate species from 11 phyla were recorded. Significant differences were detected in taxonomic richness, density, and assemblage structure of macroinvertebrates between heavily visited and pristine shores, suggesting that macroinvertebrates were adversely affected by visitors’ impact at heavily visited shores. The test of changes in species richness, density, and assemblage structure from high to low seasons yielded mixed results. The significant changes in density and assemblage structure from high to low seasons were only observed in one heavily visited shore. A significant reduction in size of striped barnacles was observed only in one heavily visited shore. The opportunistic or fugitive species (e.g., small macroalgae and barnacles) were dominant macroinvertebrates on heavily visited shores indicating early succession stage. The results presented here showed that macroinvertebrates were adversely affected by human activities in subtropical rocky shore.  相似文献   

16.
17.
Environment problems associated with the generation of waste are part of societal changes where households play an important role. These societal changes influence the size, structure and characteristic of given households. For the effective planning of solid-waste handling infrastructure, it is essential to know the quantity of waste generation and its composition. This paper presents the findings of a study carried out in an urban municipal area in Iran to determine the household solid-waste generation rate and waste composition based on field surveys and to determine the related socioeconomic parameters. The dependent variables were waste generation and composition, and independent variables were family size, family employment, age, number of room and education. Over 400 sample households were selected for the study using a stratified random sampling methodology and from five different socioeconomic groups. Waste collected from all groups of households were segregated and weighted. Waste generation rate was 5.4 kg/household/day. Household solid waste comprised of ten categories of wastes and with the largest component (76.9%). The generation and composition of household solid waste were correlated with family size, education level and households income. This paper adequately suggests new insights concerning the role of socioeconomic parameters in affecting the generation of household waste.  相似文献   

18.
The levels of 17 organochlorine pesticides residues (OCPs) in surface water and sediments from Tamiraparani river basin, South India were investigated to evaluate their potential pollution and risk impacts. A total of 96 surface water and sediment samples at 12 sampling stations were collected along the river in four seasons during 2008–2009. The ΣOCP concentrations in surface water and sediments were in the range of 0.1 to 79.9 ng l−1 and 0.12 to 3,938.7 ng g−1 dry weight (dw), respectively. Among the OCPs, the levels of dichlorodiphenyltrichloroethanes (DDTs), aldrin, dieldrin, cis-chlordane, trans-chlordane, and mirex were dominant in the sediments. The dominant OCPs in water samples are heptachlor, o,p′-DDE, dieldrin, o,p′-DDD, and mirex, which show different source of contamination pattern among sampling seasons. The distribution pattern of DDTs, hexachlorocyclohexane, and other OCPs in the present study shows heterogenic nature of nonpoint source of pollution. Notable contamination of water and sediment sample that was observed in upstream (S2) 58 ng l−1 and downstream (S11) 1,693 ng g−1 dw explains agricultural and municipal outfalls, whereas frequent damming effect reduces the concentration level in the midstream. The overall spatial–temporal distribution pattern of ΣOCP residues are illustrated by GIS package.  相似文献   

19.
20.
Tehran, the capital city of Iran, is an important industrial and commercial center. This city is one of the worst cities in the world in terms of air pollution, which is mostly due to mobile sources rather than stationary sources. Particulate matter (PM), which is a complex mixture of extremely small particles and liquid droplets, is considered as an important source of air pollution in Tehran. In this study, our objective was to study PM10, PM2.5, and PM1.0 mass and number concentrations and find the correlations of these two parameters in the west-central parts of Tehran during two consecutive warm and cold seasons. The particles collected from five stations were analyzed for their mass and number simultaneously by a laser-based Grimm dust monitor. In general, it was found that the accumulation of the PM in this region is more in the cold season. PM10 mass concentration increases almost twofold and PM2.5 and PM1.0 almost three times in this season. The mean number concentration of the particles (0.3–20 μm) was found to be almost 4.8 times in the cold season. It was also noticed that the average dimensions of the particles decrease in that season.  相似文献   

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