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Prakash Raj Kannel Sushil R. Kanel Seockheon Lee Y.-S. Lee 《Environmental monitoring and assessment》2011,172(1-4):529-545
The spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in Gomti River, a major tributary of the Ganga river (India). A total of 96 samples (water and sediments) were collected from eight different sites over a period of 2 years and analysed for 16 PAHs. The total concentrations of 16 PAHs in water and bed sediments ranged between 0.06 and 84.21 ??g/L (average (n?=?48), 10.33 ± 19.94 ??g/L) and 5.24?C3,722.87 ng/g dw [average (n?=?48): 697.25 ± 1,005.23 ng/g dw], respectively. In water, two- and three-ring PAHs and, in sediments, the three- and four-ring PAHs were the dominant species. The ratios of anthracene (An)/An + phenenthrene and fluoranthene (Fla)/Fla + pyrene were calculated to evaluate the possible sources of PAHs. These ratios reflected a pattern of pyrolytic input as a major source of PAHs in the river. Principal component analysis, further, separated the PAHs sources in the river sediments, suggesting that both the pyrolytic and petrogenic sources are contributing to the PAHs burden. The threat to biota of the river due to PAHs contamination was assessed using effect range low and effect range median values, and the results suggested that sediment at some occasions may pose biological impairment. 相似文献
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Kannel PR Lee S Kanel SR Khan SP Lee YS 《Environmental monitoring and assessment》2007,129(1-3):433-459
The study presents the assessment of variation of water qualities, classification of monitoring networks and detection of pollution sources along the Bagmati River and its tributaries in the Kathmandu valley of Nepal. Seventeen stations, monitored for 23 physical and chemical parameters in pre-monsoon, monsoon, post-monsoon and winter seasons, during the period 1999-2003, were selected for the purpose of this study. The study revealed that the upstream river water qualities in the rural areas were increasingly affected from human sewage and chemical fertilizers. In downstream urban areas, the river was heavily polluted with untreated municipal sewage. The contribution of industries to pollute the river was minimal. The higher ratio of COD to BOD (3.74 in the rural and 2.06 in the urban) confirmed the increased industrial activities in the rural areas. An increasing trend of nitrate was found in the rural areas. In the urban areas, increasing trend of phosphorus was detected. The water quality measurement in the study period showed that DO was below 4 mg/l and BOD, COD, TIN, TP and TSS above 39.1, 59.2, 10.1, 0.84 and 199 mg/l, respectively, in the urban areas. In the rural areas, DO was above 6.2 mg/l and BOD, COD, TIN, TP and TSS below 15.9, 31, 5.24, 0.41 and 134.5 mg/l, respectively. The analysis for data from 1988 to 2003 at a key station in the river revealed that BOD was increasing at a rate of 1.8 mg/l in the Bagmati River. A comparative study for the water quality variables in the urban areas showed that the main river and its tributaries were equally polluted. The other comparison showed the urban water qualities were significantly poor as compared with rural. The cluster analysis detected three distinct monitoring groups: (1) low water pollution region, (2) medium water pollution region, (3) heavy water pollution region. For rapid assessment of water qualities using the representative sites could serve to optimize cost and time without loosing any significance of the outcome. The factor analysis revealed distinct groups of sources and pollutions (organics, nutrients, solutes and physicochemical). 相似文献
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Application of Water Quality Indices and Dissolved Oxygen as Indicators for River Water Classification and Urban Impact Assessment 总被引:5,自引:0,他引:5
Kannel PR Lee S Lee YS Kanel SR Khan SP 《Environmental monitoring and assessment》2007,132(1-3):93-110
The usefulness of water quality indices, as the indicators of water pollution, for assessment of spatial-temporal changes and classification of river water qualities was verified. Four water quality indices were investigated: WQI (considering 18 water quality parameters), WQI(min) and WQI(m) (considering five water quality parameters: temperature, pH, DO, EC and TSS) and WQI(DO) (considering a single parameter, DO). The water quality indices WQI(min), WQI(m) and WQI(DO) could be of particular interest for the developing countries because of the minimum analytical cost involved. As a case study, water quality indices were used to evaluate spatial and temporal changes of the water quality in the Bagmati river basin (Nepal) for the study period 1999-2003. The results allowed us to determine the serious negative effects of the city urban activity on the river water quality. In the studied section of the river, the water quality index (WQI) was 71 units (classified as good) at the entry station and 47.6 units (classified as bad) at the outlet station. For the studied period, a significant decrease in water quality (mean WQI decrease = 11.6%, p = 0.042) was observed in the rural areas. A comparative analysis revealed that the urban water quality was significantly bad as compared with rural. The analysis enabled to classify the water quality stations into three groups: good water quality, medium water quality and bad water quality. WQI(min) resulted in overestimation of the water quality but with similar trend as with WQI and is useful for the periodic routine monitoring program. The correlation of WQI with WQI(min) and DO resulted two new indices WQI(m) and WQI(DO), respectively. The classification of waters based on WQI(m) and WQI(DO) coincided in 90 and 93% of the samples, respectively. 相似文献
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A Review of Public Domain Water Quality Models for Simulating Dissolved Oxygen in Rivers and Streams 总被引:1,自引:0,他引:1
Prakash R. Kannel Sushil R. Kanel Seockheon Lee Young-Soo Lee Thian Y. Gan 《Environmental Modeling and Assessment》2011,16(2):183-204
The review discusses six major public domain water quality models currently available for rivers and streams. These major
models, which differ greatly in terms of processes they represent, data inputs requirements, assumptions, modeling capability,
their strengths and weaknesses, could yield useful results if appropriately selected for the desired purposes. The public
domain models, which are most suitable for simulating dissolved oxygen along rivers and streams, chosen in this review are
simulation catchment (SIMCAT), temporal overall model for catchments (TOMCAT), QUAL2Kw, QUAL2EU, water quality analysis simulation
program (WASP7), and quality simulation along rivers (QUASAR). Each of these models is described based on a consistent set
of criteria-conceptualization, processes, input data, model capability, limitations, model strengths, and its application.
The results revealed that SIMCAT and TOMCAT are over-simplistic but useful to quickly assess impact of point sources. The
QUAL2Kw has provision for conversion of algal death to carbonaceous biochemical oxygen demand (CBOD) and thus more appropriate
than QUAL2EU, where macrophytes play an important interaction. The extensive requirement of data in WASP7 and QUASAR is difficult
to justify the time and costs required to set up these complex models. Thus, a single model could not serve all wide range
of functionalities required. The choice of a model depends upon availability of time, financial cost and a specific application.
This review may help to choose appropriate model for a particular water quality problem. 相似文献
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Application of QUAL2Kw for water quality modeling and dissolved oxygen control in the river Bagmati 总被引:1,自引:0,他引:1
Kannel PR Lee S Kanel SR Lee YS Ahn KH 《Environmental monitoring and assessment》2007,125(1-3):201-217
A stream water quality model, QUAL2Kw, was calibrated and validated for the river Bagmati of Nepal. The model represented
the field data quite well with some exceptions. The influences of various water quality management strategies have on DO concentrations
were examined considering: (i) pollution loads modification; (ii) flow augmentation; (iii) local oxygenation. The study showed
the local oxygenation is effective in raising DO levels. The combination of wastewater modification, flow augmentation and
local oxygenation is necessary to ensure minimum DO concentrations. This reasonable modeling guarantees the use of QUAL2Kw
for future river water quality policy options. 相似文献
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