In this paper, perhaps for the first time, a data-driven simulation–optimization model is developed based on experimental results to find the effects of state and decision variables on the optimum characteristics of a stilling basin with adverse slope and corrugated bed. The optimal design parameters of the stilling basin are investigated to minimize the length of the hydraulic jump and ratio of the sequent depths of the jump while the relative amount of energy loss is maximized. In order to model the relationship between design variables of the bed, the experimental results are converted to a data-driven simulation model on the basis of a multilayer perceptron (MLP) neural network. Then, the validated MLP model is used in a genetic algorithm optimization model in order to determine the optimum characteristics of the bed under the hydraulic jump considering the interaction between the bed design variables and the hydraulic parameters of the flow. Results indicate that the optimum values of bed slope and the diameter of the corrugated roughness (2 r ) can be considered as −0.02 and 20 millimetres, respectively.
{"title":"Hydraulic optimization of corrugated stilling basin with adverse slope","authors":"T. Honar, Nafiseh Khoramshokooh, M. Nikoo","doi":"10.2166/WS.2018.079","DOIUrl":"https://doi.org/10.2166/WS.2018.079","url":null,"abstract":"In this paper, perhaps for the first time, a data-driven simulation–optimization model is developed based on experimental results to find the effects of state and decision variables on the optimum characteristics of a stilling basin with adverse slope and corrugated bed. The optimal design parameters of the stilling basin are investigated to minimize the length of the hydraulic jump and ratio of the sequent depths of the jump while the relative amount of energy loss is maximized. In order to model the relationship between design variables of the bed, the experimental results are converted to a data-driven simulation model on the basis of a multilayer perceptron (MLP) neural network. Then, the validated MLP model is used in a genetic algorithm optimization model in order to determine the optimum characteristics of the bed under the hydraulic jump considering the interaction between the bed design variables and the hydraulic parameters of the flow. Results indicate that the optimum values of bed slope and the diameter of the corrugated roughness (2 r ) can be considered as −0.02 and 20 millimetres, respectively.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87479887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water temperature is an important indicator for biodiversity and ecosystem sustainability. In this study, a simplified equilibrium temperature model was incorporated into the CE-QUAL-W2 (W2) model. This model is easy to implement, needing fewer meteorological variables and no parameter calibration. The model performance was evaluated using observed data from four stations on the Lower Minnesota River. Results show that the simplified equilibrium temperature model performed as well as the original equilibrium temperature model and the term-by-term process model for water temperature predictions with the values of the coefficient of determination ( R 2 ), Nash–Sutcliffe Efficiency (NSE), and Percent Error (PE) in the accepted range ( R 2 = 0.974, NSE = 0.972, PE = 1.377%). The impact of the water temperature on Carbonaceous Biochemical Oxygen Demand (CBOD) concentrations under three different water temperature models was evaluated, and results show that the monthly averaged CBOD concentrations of the simplified equilibrium temperature model were almost the same as that of the term-by-term approach. For all the four calibration stations, the simplified equilibrium temperature approach performs better than the other two models for dissolved oxygen simulation ( R 2 = 0.791, NSE = 0.65, PE = 7.596%), which indicates that the simplified equilibrium temperature model can be a potential tool to simulate water temperature for water quality modelling.
{"title":"Incorporation of the simplified equilibrium temperature approach in a hydrodynamic and water quality model – CE-QUAL-W2","authors":"Senlin Zhu, Xinzhong Du, Wenguang Luo","doi":"10.2166/WS.2018.063","DOIUrl":"https://doi.org/10.2166/WS.2018.063","url":null,"abstract":"Water temperature is an important indicator for biodiversity and ecosystem sustainability. In this study, a simplified equilibrium temperature model was incorporated into the CE-QUAL-W2 (W2) model. This model is easy to implement, needing fewer meteorological variables and no parameter calibration. The model performance was evaluated using observed data from four stations on the Lower Minnesota River. Results show that the simplified equilibrium temperature model performed as well as the original equilibrium temperature model and the term-by-term process model for water temperature predictions with the values of the coefficient of determination ( R 2 ), Nash–Sutcliffe Efficiency (NSE), and Percent Error (PE) in the accepted range ( R 2 = 0.974, NSE = 0.972, PE = 1.377%). The impact of the water temperature on Carbonaceous Biochemical Oxygen Demand (CBOD) concentrations under three different water temperature models was evaluated, and results show that the monthly averaged CBOD concentrations of the simplified equilibrium temperature model were almost the same as that of the term-by-term approach. For all the four calibration stations, the simplified equilibrium temperature approach performs better than the other two models for dissolved oxygen simulation ( R 2 = 0.791, NSE = 0.65, PE = 7.596%), which indicates that the simplified equilibrium temperature model can be a potential tool to simulate water temperature for water quality modelling.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76764877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In 2012, the South African Department of Water and Sanitation (DWS) initiated a study: Continuation of the Northern Planning Region9s All Towns Reconciliation Strategies: Phase 1. This study reviewed, prioritised and updated the rudimentary All Towns strategies initially developed by DWS in 2011. The purpose of the strategies was to reconcile water requirements with available resources for the 2011–2035 planning horizon by estimating the projected water requirements, determining available water resources (surface and groundwater) and developing a water balance. Recommendations were made to conserve, manage and administer local water sources as well as to augment water supplies from other sources if required. The recommendations provided actions and options for implementation by the relevant Water Services Authorities and the DWS at a local and regional level, providing the opportunity for integrated and coordinated planning. Bulk and reticulation metering, the implementation of water conservation and demand management programmes and recommendations on the updating of water use allocations were prioritised. Detailed studies required to determine the most feasible water resource augmentation options to ensure a positive water balance were identified. The study coordinated efforts by officials and stakeholders representing both the water resources and water services sectors. The prioritised strategies defined the deficit or surplus of the water resources per water source on a technical level, but also highlighted the need for planning and coordination between the water resources and water services sectors. The strategies are not legally mandated documents, but represent some of the best efforts spanning across various sectors to realise coordinated water infrastructure planning in DWS’ Northern Planning Region. The use of the documents in the local, district and national planning environments should be promoted for integrated planning, and it may be fitting to incorporate the All Towns Reconciliation Strategy documents as a valuable resource to inform the water legislation currently being reviewed.
{"title":"The All Towns Reconciliation Strategies a partnership between water resource management and water services","authors":"M. Esterhuizen, L. D. Jager, W. Jeżewski","doi":"10.2166/WS.2018.054","DOIUrl":"https://doi.org/10.2166/WS.2018.054","url":null,"abstract":"In 2012, the South African Department of Water and Sanitation (DWS) initiated a study: Continuation of the Northern Planning Region9s All Towns Reconciliation Strategies: Phase 1. This study reviewed, prioritised and updated the rudimentary All Towns strategies initially developed by DWS in 2011. The purpose of the strategies was to reconcile water requirements with available resources for the 2011–2035 planning horizon by estimating the projected water requirements, determining available water resources (surface and groundwater) and developing a water balance. Recommendations were made to conserve, manage and administer local water sources as well as to augment water supplies from other sources if required. The recommendations provided actions and options for implementation by the relevant Water Services Authorities and the DWS at a local and regional level, providing the opportunity for integrated and coordinated planning. Bulk and reticulation metering, the implementation of water conservation and demand management programmes and recommendations on the updating of water use allocations were prioritised. Detailed studies required to determine the most feasible water resource augmentation options to ensure a positive water balance were identified. The study coordinated efforts by officials and stakeholders representing both the water resources and water services sectors. The prioritised strategies defined the deficit or surplus of the water resources per water source on a technical level, but also highlighted the need for planning and coordination between the water resources and water services sectors. The strategies are not legally mandated documents, but represent some of the best efforts spanning across various sectors to realise coordinated water infrastructure planning in DWS’ Northern Planning Region. The use of the documents in the local, district and national planning environments should be promoted for integrated planning, and it may be fitting to incorporate the All Towns Reconciliation Strategy documents as a valuable resource to inform the water legislation currently being reviewed.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86003993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Impurities and colloidal substances are two of many fouling conditions that reduce the membrane filtration performance used in wastewater treatment. This study investigates the potential of fluidic oscillation generated microbubbles (MBs) to defoul the filtration membrane. Cartridge filters of microfiltration (MF) of 1 μm pore size were fouled using surface seawater collected from the Hull coastal area. The seawater was circulated at 5.8 L/min to actuate colloidal substance deposition on the membrane surface. The recorded feed channel pressure drop (Δ P ) across the membrane filters shown rapid fouling occurred in the first 8 hrs of the circulation. Fluctuations of Δ P during the next 8 hrs were observed showing the colloids filling the pores of the membrane, remaining steady for two hours showing membrane was completely fouled. The filtration membrane was cleaned and defouled using fluidic oscillator generated MBs. The fouled membranes were sparged with 1 L/min of air scouring for ∼1 to ∼2 hrs to remove the deposited colloids and impurities on the surface of the membrane. The membrane, analysed under Scanning Electron Microscopy (SEM), UV 254 and EC meter, shows the extent of MBs mediated removal of the deposited colloidal particle from the membrane surfaces. This study found that the highest defouling rate occurs with MBs generated by fluidic oscillator (closed vent), followed by MBs generated by fluidic oscillator (opened vent) and MBs generated without fluidic oscillator are9.53, 6.22, and 3.41 mbar/min, respectively.
{"title":"Membrane defouling using microbubbles generated by fluidic oscillation","authors":"M. Harun, W. Zimmerman","doi":"10.2166/WS.2018.056","DOIUrl":"https://doi.org/10.2166/WS.2018.056","url":null,"abstract":"Impurities and colloidal substances are two of many fouling conditions that reduce the membrane filtration performance used in wastewater treatment. This study investigates the potential of fluidic oscillation generated microbubbles (MBs) to defoul the filtration membrane. Cartridge filters of microfiltration (MF) of 1 μm pore size were fouled using surface seawater collected from the Hull coastal area. The seawater was circulated at 5.8 L/min to actuate colloidal substance deposition on the membrane surface. The recorded feed channel pressure drop (Δ P ) across the membrane filters shown rapid fouling occurred in the first 8 hrs of the circulation. Fluctuations of Δ P during the next 8 hrs were observed showing the colloids filling the pores of the membrane, remaining steady for two hours showing membrane was completely fouled. The filtration membrane was cleaned and defouled using fluidic oscillator generated MBs. The fouled membranes were sparged with 1 L/min of air scouring for ∼1 to ∼2 hrs to remove the deposited colloids and impurities on the surface of the membrane. The membrane, analysed under Scanning Electron Microscopy (SEM), UV 254 and EC meter, shows the extent of MBs mediated removal of the deposited colloidal particle from the membrane surfaces. This study found that the highest defouling rate occurs with MBs generated by fluidic oscillator (closed vent), followed by MBs generated by fluidic oscillator (opened vent) and MBs generated without fluidic oscillator are9.53, 6.22, and 3.41 mbar/min, respectively.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74046933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Eris, H. Aksoy, B. Önöz, M. Cetin, M. Yuce, Bülent Selek, H. Aksu, Halil Ibrahim Burgan, Musa Eşit, Isilsu Yildirim, Ece Karakus
This study attempts to find out the best-fit probability distribution function to low flows using the up-to-date data of intermittent and non-intermittent rivers in four hydrological basins from different regions in Turkey. Frequency analysis of D = 1, 7, 14, 30, 90 and 273-day low flows calculated from the daily flow time series of each stream gauge was performed. Weibull (W2), Gamma (G2), Generalized Extreme Value (GEV) and Log-Normal (LN2) are selected among the 2-parameter probability distribution functions together with the Weibull (W3), Gamma (G3) and Log-Normal (LN3) from the 3-parameter probability distribution functions family. Selected probability distribution functions are checked for their suitability to fit each D -day low flow sequence. LN3 mostly conforms low flows by being the best-fit among the selected probability distribution functions in three out of four hydrological basins while W3 fits low flows in one basin. With the use of the best-fit probability distribution function, the low flow-duration-frequency curves are determined which has the ability to provide the end-users with any D -day low flow discharge of any given return period.
{"title":"Frequency analysis of low flows in intermittent and non-intermittent rivers from hydrological basins in Turkey","authors":"E. Eris, H. Aksoy, B. Önöz, M. Cetin, M. Yuce, Bülent Selek, H. Aksu, Halil Ibrahim Burgan, Musa Eşit, Isilsu Yildirim, Ece Karakus","doi":"10.2166/WS.2018.051","DOIUrl":"https://doi.org/10.2166/WS.2018.051","url":null,"abstract":"This study attempts to find out the best-fit probability distribution function to low flows using the up-to-date data of intermittent and non-intermittent rivers in four hydrological basins from different regions in Turkey. Frequency analysis of D = 1, 7, 14, 30, 90 and 273-day low flows calculated from the daily flow time series of each stream gauge was performed. Weibull (W2), Gamma (G2), Generalized Extreme Value (GEV) and Log-Normal (LN2) are selected among the 2-parameter probability distribution functions together with the Weibull (W3), Gamma (G3) and Log-Normal (LN3) from the 3-parameter probability distribution functions family. Selected probability distribution functions are checked for their suitability to fit each D -day low flow sequence. LN3 mostly conforms low flows by being the best-fit among the selected probability distribution functions in three out of four hydrological basins while W3 fits low flows in one basin. With the use of the best-fit probability distribution function, the low flow-duration-frequency curves are determined which has the ability to provide the end-users with any D -day low flow discharge of any given return period.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84657130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reference conditions of Chlorophyll- a in lakes should be established in order to improve the water quality in these water bodies. A new method using segmental linear regression was developed to estimate the reference condition of Chlorophyll- a . The method can overcome the shortcomings of other methods, such as the quantile-selection-based method, which contains a certain level of subjectivity. The new method was used to estimate the annual reference condition of Chlorophyll- a in Taihu Lake. The log–log segmental regression results indicate that the distribution of specific volume (reciprocal of concentration) of Chlorophyll- a in Taihu Lake had a power-law tail. Both segmental regression and bootstrap approaches show two credible change points in the power-law relationship. This study9s analysis shows that the value of 4.4 mg·m −3 was an appropriate annual reference value of Chlorophyll- a in Taihu Lake. Thus, the method would be useful in determining the numerical reference conditions of Chlorophyll- a for other shallow lakes.
{"title":"Estimation of annual reference condition of chlorophyll-a based on the segmental linear regression and power-Law relationship in taihu lake","authors":"Liang Wang, Z. Hua, Wang Yulin","doi":"10.2166/WS.2018.060","DOIUrl":"https://doi.org/10.2166/WS.2018.060","url":null,"abstract":"The reference conditions of Chlorophyll- a in lakes should be established in order to improve the water quality in these water bodies. A new method using segmental linear regression was developed to estimate the reference condition of Chlorophyll- a . The method can overcome the shortcomings of other methods, such as the quantile-selection-based method, which contains a certain level of subjectivity. The new method was used to estimate the annual reference condition of Chlorophyll- a in Taihu Lake. The log–log segmental regression results indicate that the distribution of specific volume (reciprocal of concentration) of Chlorophyll- a in Taihu Lake had a power-law tail. Both segmental regression and bootstrap approaches show two credible change points in the power-law relationship. This study9s analysis shows that the value of 4.4 mg·m −3 was an appropriate annual reference value of Chlorophyll- a in Taihu Lake. Thus, the method would be useful in determining the numerical reference conditions of Chlorophyll- a for other shallow lakes.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76831674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper presents a detailed analysis of the quality of water pumped into the network and sampled from 39 monitoring points located on the network. A difference in the quality of water sampled from two different sources has been demonstrated, as well as the impact of mixing of the two waters in the water distribution system on tap water quality. A mathematical model was used to identify the zones of water mixing and the areas of unfavourable hydraulic conditions (low flow rates and long retention times).
{"title":"The effect of the mixing of water from different sources in the water supply system on tap water quality – a full-scale technical investigation case study","authors":"Agnieszka Szuster-Janiaczyk, J. Bylka","doi":"10.2166/WS.2018.075","DOIUrl":"https://doi.org/10.2166/WS.2018.075","url":null,"abstract":"The paper presents a detailed analysis of the quality of water pumped into the network and sampled from 39 monitoring points located on the network. A difference in the quality of water sampled from two different sources has been demonstrated, as well as the impact of mixing of the two waters in the water distribution system on tap water quality. A mathematical model was used to identify the zones of water mixing and the areas of unfavourable hydraulic conditions (low flow rates and long retention times).","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81089112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Households in the rural areas of southwest coastal Bangladesh mainly depend on unreliable sources of drinking water. This study assessed the willingness to pay (WTP) for improved drinking water in a rural area of the southwest coastal Bangladesh, using contingent valuation survey data of 215 households. The samples for the face-to-face interview were selected by purposive random sampling from Chila union of Mongla sub-district under Bagerhat district. The mean WTP for improved drinking water was estimated to be BDT 193 (US$ 2.47) per month (3% of the monthly income of the households). Results also indicate that educated respondents and households with higher income are willing to pay more for improved water supply. Moreover, the expenditure of the households for buying water and for medicine for waterborne diseases has a significant positive impact on the WTP. The results of this study can be useful for decision-makers to promote improved drinking water supply in southwest coastal Bangladesh.
{"title":"Willingness to pay for improved drinking water in southwest coastal Bangladesh","authors":"Ma Islam, Md. Ali Akber, Md. Atikul Islam","doi":"10.2166/WS.2018.047","DOIUrl":"https://doi.org/10.2166/WS.2018.047","url":null,"abstract":"Households in the rural areas of southwest coastal Bangladesh mainly depend on unreliable sources of drinking water. This study assessed the willingness to pay (WTP) for improved drinking water in a rural area of the southwest coastal Bangladesh, using contingent valuation survey data of 215 households. The samples for the face-to-face interview were selected by purposive random sampling from Chila union of Mongla sub-district under Bagerhat district. The mean WTP for improved drinking water was estimated to be BDT 193 (US$ 2.47) per month (3% of the monthly income of the households). Results also indicate that educated respondents and households with higher income are willing to pay more for improved water supply. Moreover, the expenditure of the households for buying water and for medicine for waterborne diseases has a significant positive impact on the WTP. The results of this study can be useful for decision-makers to promote improved drinking water supply in southwest coastal Bangladesh.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80799186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yiming Zhang, Yunxiang Li, You-ping Li, Wenyi Da, Mao-Lei Yu, Qiu-mei Quan
This study evaluated temporal and spatial variations in water quality to understand the characteristics of the Jialing River watershed in Guangyuan City, China. Data on 17 parameters obtained from seven sites from 2012 to 2015, with a total of 329 samples for each parameter, were analyzed using multivariate statistical techniques. Observation months were grouped into two periods (Period A, May–November; Period B, December–April) according to similarities in water quality characteristics through time analysis and cluster analysis (CA). Water temperature (TEMP), flow rate (Q), dissolved oxygen (DO), oils, fluoride (F) and cadmium (Cd) were the most significant parameters for discriminating between the two periods. Through a spatial analysis, the sites were classified into two groups (Groups 1 and 2). Q, total phosphorus (TP), oils, F and fecal coliform bacteria (F. coli ) were the most significant parameters for discriminating between the two groups. Results suggested that TEMP, DO and Cd as functions of time, TP and F . coli as functions of space, and Q, oils and F as functions of both time and space should be monitored closely. The main sources of water pollutant were surface runoff and industrial wastewater, of time, and wastewater from agricultural irrigation, industrial wastewater, and municipal sewage, of space.
{"title":"Application of multivariate statistical methods in the assessment of water quality in selected locations in Jialing River basin in Guangyuan, China","authors":"Yiming Zhang, Yunxiang Li, You-ping Li, Wenyi Da, Mao-Lei Yu, Qiu-mei Quan","doi":"10.2166/WS.2018.058","DOIUrl":"https://doi.org/10.2166/WS.2018.058","url":null,"abstract":"This study evaluated temporal and spatial variations in water quality to understand the characteristics of the Jialing River watershed in Guangyuan City, China. Data on 17 parameters obtained from seven sites from 2012 to 2015, with a total of 329 samples for each parameter, were analyzed using multivariate statistical techniques. Observation months were grouped into two periods (Period A, May–November; Period B, December–April) according to similarities in water quality characteristics through time analysis and cluster analysis (CA). Water temperature (TEMP), flow rate (Q), dissolved oxygen (DO), oils, fluoride (F) and cadmium (Cd) were the most significant parameters for discriminating between the two periods. Through a spatial analysis, the sites were classified into two groups (Groups 1 and 2). Q, total phosphorus (TP), oils, F and fecal coliform bacteria (F. coli ) were the most significant parameters for discriminating between the two groups. Results suggested that TEMP, DO and Cd as functions of time, TP and F . coli as functions of space, and Q, oils and F as functions of both time and space should be monitored closely. The main sources of water pollutant were surface runoff and industrial wastewater, of time, and wastewater from agricultural irrigation, industrial wastewater, and municipal sewage, of space.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86133504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Remote sensing is an effective tool for studying CDOM (colored dissolved organic matter) variations and its relevant environmental factors. Monitoring CDOM distribution and dynamics in small water is often limited by the coarse spatial resolution of traditional ocean color sensors. In this study, because of its high spatial resolution of 30 m, Landsat-8 data were used to assess seasonal variations of CDOM in the Saginaw River, by using an empirical statistic model. Pearson correlation analysis between CDOM variations and other environmental factors, such as temperature, discharge, and dissolved oxygen, shows that temperature was negatively correlated to CDOM variations and discharge played a positive role. We also calculated the monthly mean a CDOM (440) (the absorption coefficient of CDOM at 440 nm) for the Saginaw River between April and November from 2013 to 2016. This study demonstrates a good example for future applications in small waters: observing CDOM variations and other relevant environmental factors change by using Landsat remote sensing, so that we can know more about water quality and ecosystem health of small waters as well as the climate change impact on regional watersheds.
{"title":"Monitoring seasonal variations of colored dissolved organic matter for the Saginaw River based on Landsat-8 data","authors":"Jiang Chen, Weining Zhu, Yuhan Zheng, Yong Q. Tian, Qian Yu","doi":"10.2166/WS.2018.077","DOIUrl":"https://doi.org/10.2166/WS.2018.077","url":null,"abstract":"Remote sensing is an effective tool for studying CDOM (colored dissolved organic matter) variations and its relevant environmental factors. Monitoring CDOM distribution and dynamics in small water is often limited by the coarse spatial resolution of traditional ocean color sensors. In this study, because of its high spatial resolution of 30 m, Landsat-8 data were used to assess seasonal variations of CDOM in the Saginaw River, by using an empirical statistic model. Pearson correlation analysis between CDOM variations and other environmental factors, such as temperature, discharge, and dissolved oxygen, shows that temperature was negatively correlated to CDOM variations and discharge played a positive role. We also calculated the monthly mean a CDOM (440) (the absorption coefficient of CDOM at 440 nm) for the Saginaw River between April and November from 2013 to 2016. This study demonstrates a good example for future applications in small waters: observing CDOM variations and other relevant environmental factors change by using Landsat remote sensing, so that we can know more about water quality and ecosystem health of small waters as well as the climate change impact on regional watersheds.","PeriodicalId":23573,"journal":{"name":"Water Science & Technology: Water Supply","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81023228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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