Particulate-associated trace metals have been regarded as an important pollution source for urban surface runoff.Cd,Pb,Cu,Zn and total solids(TS)washed off two different surfaces(low-elevated facade and road surfaces)...Particulate-associated trace metals have been regarded as an important pollution source for urban surface runoff.Cd,Pb,Cu,Zn and total solids(TS)washed off two different surfaces(low-elevated facade and road surfaces)under two kinds of antecedent environmental conditions(dry and snow-melting)were determined in this study.Wet-vacuuming sweeping(WVS)and surface washing(SW)methods,representing the maximum pollution potential and common rainfall-induced wash-off condition respectively,were used to collect the particulate matters.The result shows that the wash-off concentrations of trace metals were found in the order of Cd(2.28±2.08 mg/l)<Pb(435.85±412.61 mg/l)<Cu(0.93±0.61 mg/l)<Zn(2.52±2.30 mg/l).The snow-melting process had a considerable influence on the wash-off concentrations of the trace metals on both road and facade surfaces.It reduced >38% and >79% of metals and TS concentrations in the facade surface and road surface runoff respectively.The wash-off concentrations of Cd,Cu,and Zn on the road surface 45e780% higher than those on the facade surfaces.The sensitivity analysis based on the Bayesian network indicates that the wash-off concentrations of metals were mainly dependent on the antecedent environmental conditions or the surface properties while the sampling methods had a minor influence.Therefore,to accurately model the pollutant migration in the surface runoff requires an improving method considering different surfaces and antecedent environment conditions.展开更多
Continuous urbanization over the last few years has led to the increase in impervious surfaces and stormwater runoff.Low Impact Development(LID)is currently receiving increased attention as a promising strategy for su...Continuous urbanization over the last few years has led to the increase in impervious surfaces and stormwater runoff.Low Impact Development(LID)is currently receiving increased attention as a promising strategy for surface runoff management.To analyze the performance of LID practices for surface runoff management,a longterm hydrological modeling from 2001 to 2015 along with a cost-effectiveness analysis were carried out on a campus in Dresden,Germany.Seven LID practices and six precipitation scenarios were designed and simulated in a Storm Water Management Model(SWMM).A cost-effectiveness analysis was conducted by calculating the lifecycle costs and runoff removal rate of LID practices.Results demonstrated that the LID practices significantly contributed to surface runoff mitigation in the study area.The LID performance was primarily affected by the length of the precipitation scenarios and LID implementing schemes.The runoff removal rate of the LID practices fluctuated significantly when the rainfall scenario was shorter than 12 months.When the rainfall scenario exceeded 1 year the effects on the runoff removal rate was constant.The combination of an infiltration trench,permeable pavement,and rain barrel(IT+PP+RB),was the best runoff control capacity with a removal rate ranging from 23.2% to 27.4%.Whereas,the rain barrel was the most cost-effective LID option with a costeffectiveness(C/E)ratio ranged from 0.34 to 0.41.The modeling method was improved in this study by conducting long-term hydrological simulations with different durations rather than short-term simulations with single storms.In general,the methods and results of this study provided additional improvements and guidance for decision-making process regarding the implementation of appropriate LID practices.展开更多
基金jointly supported by the project of“Collaborative early warning information systems for urban infrastructures(COLABIS)”funded by German Federal Ministry of Education and Research(BMBF,Grant No.:03G0852A).
文摘Particulate-associated trace metals have been regarded as an important pollution source for urban surface runoff.Cd,Pb,Cu,Zn and total solids(TS)washed off two different surfaces(low-elevated facade and road surfaces)under two kinds of antecedent environmental conditions(dry and snow-melting)were determined in this study.Wet-vacuuming sweeping(WVS)and surface washing(SW)methods,representing the maximum pollution potential and common rainfall-induced wash-off condition respectively,were used to collect the particulate matters.The result shows that the wash-off concentrations of trace metals were found in the order of Cd(2.28±2.08 mg/l)<Pb(435.85±412.61 mg/l)<Cu(0.93±0.61 mg/l)<Zn(2.52±2.30 mg/l).The snow-melting process had a considerable influence on the wash-off concentrations of the trace metals on both road and facade surfaces.It reduced >38% and >79% of metals and TS concentrations in the facade surface and road surface runoff respectively.The wash-off concentrations of Cd,Cu,and Zn on the road surface 45e780% higher than those on the facade surfaces.The sensitivity analysis based on the Bayesian network indicates that the wash-off concentrations of metals were mainly dependent on the antecedent environmental conditions or the surface properties while the sampling methods had a minor influence.Therefore,to accurately model the pollutant migration in the surface runoff requires an improving method considering different surfaces and antecedent environment conditions.
基金jointly supported by the COLABIS project(Collaborative Early Warning Information Systems for Urban Infrastructures,Grant No.:03G0852A)Managing Water Resources for Urban Catchments project in the framework of the Sino-German“Innovation Cluster Major Water”(Grant No.:02WCL1337A-K)funded by German Federal Ministry of Education and Research(BMBF).
文摘Continuous urbanization over the last few years has led to the increase in impervious surfaces and stormwater runoff.Low Impact Development(LID)is currently receiving increased attention as a promising strategy for surface runoff management.To analyze the performance of LID practices for surface runoff management,a longterm hydrological modeling from 2001 to 2015 along with a cost-effectiveness analysis were carried out on a campus in Dresden,Germany.Seven LID practices and six precipitation scenarios were designed and simulated in a Storm Water Management Model(SWMM).A cost-effectiveness analysis was conducted by calculating the lifecycle costs and runoff removal rate of LID practices.Results demonstrated that the LID practices significantly contributed to surface runoff mitigation in the study area.The LID performance was primarily affected by the length of the precipitation scenarios and LID implementing schemes.The runoff removal rate of the LID practices fluctuated significantly when the rainfall scenario was shorter than 12 months.When the rainfall scenario exceeded 1 year the effects on the runoff removal rate was constant.The combination of an infiltration trench,permeable pavement,and rain barrel(IT+PP+RB),was the best runoff control capacity with a removal rate ranging from 23.2% to 27.4%.Whereas,the rain barrel was the most cost-effective LID option with a costeffectiveness(C/E)ratio ranged from 0.34 to 0.41.The modeling method was improved in this study by conducting long-term hydrological simulations with different durations rather than short-term simulations with single storms.In general,the methods and results of this study provided additional improvements and guidance for decision-making process regarding the implementation of appropriate LID practices.
