Kafr El-Dawar is a major industrial city and a municipality on the Nile Delta in northern Egypt. Kafr El-Dawar area is unfortunately suffering from many factories that let out their waste water into the irrigation can...Kafr El-Dawar is a major industrial city and a municipality on the Nile Delta in northern Egypt. Kafr El-Dawar area is unfortunately suffering from many factories that let out their waste water into the irrigation canal and agricultural drains. Twenty five water samples were collected from five water resources to assess their heavy pollution. The determination of heavy metals (HV) water resources content conducted to compose the following increasing HV concentration sequences;Drain Abu Qir (DA): Min (Cu)_Max (Zn), Canal Dbora Deufsho (CD): Min (Cu)_Max (Zn), Drain Dbora Abu Qir (DD): Min (Cu)_Max (Fe), Drain Kafr Dawar Deufsho (DK) : Min (Cu)_Max (Mn) and Drain Yarn and Fabric (DY) Min (Cu)_Max (Zn). Distribution patterns of HV concentration of water resources were (a) wide spread-distribution (Cr, Co, Mn), (b) moderately spread distribution pattern (Cu, Ni, Pb),and (c) narrow spread distribution pattern (Fe, Cd, Li and Zn) . The association study conducted to classify the HV concentration into three groups;positively highly correlated HV: (Pb_Cd), (Pb_Co), (Pb_Cr), (Cd_Co), (Zn_Fe), (Cr_Co), (Ni_Co) and (Ni_Fe), negatively highly correlated HV: (Pb_Mn), (Cd_Mn), (Mn_Cu) and (Co_Li) and intermediate cases (non-significant positive and negative intercorrelation) that was represented by the other cases. The low values of contamination factor, of short term use (CfiST), showed that the majority of HV concentration, of the studied water resources was at safe use level. This certainly with exception of the cases of cadmium that classified the water resources DA and CD, and DD into polluted and risky levels, respectively. The high values of contamination factor, of long term use (CfiLT), indicated that the studied water resources were mainly contaminated by Cd, Co and Cr heavy metals. Contrary, the low values of (CfiLT) of Zn, Fe, Li, Ni, Pb and Cu, all studied water resources are safe. Contamination degree index (Cd) indicated the safe use at short term of water resources (DA), (CD) and (DD), and (DY) water resources were highly contaminated. According to (Cd) values, moderate risk is expected if we use the water resource (DK), even in the short term. As for the long term use, all studied water resources were highly contaminated that they cannot be absolutely used in the long run.展开更多
Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event...Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event mean concentrations （EMC） of dissolved copper （Cu）, lead （Pb）, zinc （Zn）, manganese （Mn）, and iron （Fe） exceeded China＇s National Water Quality Standards for Surface Water. The degree of heavy metal contamination was related to the type of underlying surfaces. Additionally, the concentration of dissolved heavy metals peaked shortly after the runoff began and then declined sharply as a result of adequate flushing. First flush effects of varying degrees were also observed during all of the monitored rainfall events based on the first flush ratio （FF25）. Redundancy analysis revealed that four environmental variables （rain- fall depth, intensity, antecedent dry weather period and type of underlying surface） had significant effects on the strengths of the first flush effects, accounting for 72.9% of the variation in the FF25. Dissolved metals presented varying first flush effects on different underlying surfaces that occurred in the following relative order： parking lot 〉 roof〉 road for low intensity and high runoff volume rainfall events; parking lot 〉 road 〉 roof for high intensity and low runoff volume events. The relative strength of the first flush for dissolved heavy metals was Fe, Mn 〉 Cu, Zn 〉 Pb.展开更多
文摘Kafr El-Dawar is a major industrial city and a municipality on the Nile Delta in northern Egypt. Kafr El-Dawar area is unfortunately suffering from many factories that let out their waste water into the irrigation canal and agricultural drains. Twenty five water samples were collected from five water resources to assess their heavy pollution. The determination of heavy metals (HV) water resources content conducted to compose the following increasing HV concentration sequences;Drain Abu Qir (DA): Min (Cu)_Max (Zn), Canal Dbora Deufsho (CD): Min (Cu)_Max (Zn), Drain Dbora Abu Qir (DD): Min (Cu)_Max (Fe), Drain Kafr Dawar Deufsho (DK) : Min (Cu)_Max (Mn) and Drain Yarn and Fabric (DY) Min (Cu)_Max (Zn). Distribution patterns of HV concentration of water resources were (a) wide spread-distribution (Cr, Co, Mn), (b) moderately spread distribution pattern (Cu, Ni, Pb),and (c) narrow spread distribution pattern (Fe, Cd, Li and Zn) . The association study conducted to classify the HV concentration into three groups;positively highly correlated HV: (Pb_Cd), (Pb_Co), (Pb_Cr), (Cd_Co), (Zn_Fe), (Cr_Co), (Ni_Co) and (Ni_Fe), negatively highly correlated HV: (Pb_Mn), (Cd_Mn), (Mn_Cu) and (Co_Li) and intermediate cases (non-significant positive and negative intercorrelation) that was represented by the other cases. The low values of contamination factor, of short term use (CfiST), showed that the majority of HV concentration, of the studied water resources was at safe use level. This certainly with exception of the cases of cadmium that classified the water resources DA and CD, and DD into polluted and risky levels, respectively. The high values of contamination factor, of long term use (CfiLT), indicated that the studied water resources were mainly contaminated by Cd, Co and Cr heavy metals. Contrary, the low values of (CfiLT) of Zn, Fe, Li, Ni, Pb and Cu, all studied water resources are safe. Contamination degree index (Cd) indicated the safe use at short term of water resources (DA), (CD) and (DD), and (DY) water resources were highly contaminated. According to (Cd) values, moderate risk is expected if we use the water resource (DK), even in the short term. As for the long term use, all studied water resources were highly contaminated that they cannot be absolutely used in the long run.
文摘Stormwater runoff from three types of urban surfaces, a parking lot, a street, and a building roof, was monitored during four rainfall events that occurred in the one-year period from June 2009 to June 2010. The event mean concentrations （EMC） of dissolved copper （Cu）, lead （Pb）, zinc （Zn）, manganese （Mn）, and iron （Fe） exceeded China＇s National Water Quality Standards for Surface Water. The degree of heavy metal contamination was related to the type of underlying surfaces. Additionally, the concentration of dissolved heavy metals peaked shortly after the runoff began and then declined sharply as a result of adequate flushing. First flush effects of varying degrees were also observed during all of the monitored rainfall events based on the first flush ratio （FF25）. Redundancy analysis revealed that four environmental variables （rain- fall depth, intensity, antecedent dry weather period and type of underlying surface） had significant effects on the strengths of the first flush effects, accounting for 72.9% of the variation in the FF25. Dissolved metals presented varying first flush effects on different underlying surfaces that occurred in the following relative order： parking lot 〉 roof〉 road for low intensity and high runoff volume rainfall events; parking lot 〉 road 〉 roof for high intensity and low runoff volume events. The relative strength of the first flush for dissolved heavy metals was Fe, Mn 〉 Cu, Zn 〉 Pb.
