The aim of this study was to determine the unit load of NPS (non-point source) pollutants including organic variables such as BOD (biochemical oxygen demand), COD (chemical oxygen demand) and DOC (dissolved org...The aim of this study was to determine the unit load of NPS (non-point source) pollutants including organic variables such as BOD (biochemical oxygen demand), COD (chemical oxygen demand) and DOC (dissolved organic carbon), nitrogen and phosphorus constituents, and suspended solids (SS) and their event mean concentration (EMC) of runoff flows from a water-shed of mixed forest land use by intensive field experiments. Field monitoring for continuous measurements of rainfall, flow, and water quality was conducted over 12 storm events during 2008-2009 using automated and manual sampling methods. The EMCs of individual runoff event were estimated for each water quality constituent based on the flow rate and concentration data of runoff discharge. The average EMCs of BOD, COD, DOC, SS, TN (total nitrogen), NH4^+-N, NO3^--N, TP (total phosphorus), PO4^3-P from the mixed forest land were 1.794, 3.498, 1.462, 10.269, 0.862, 0.044, 0.634, 0.034, and 0.005 mg/L, respectively. The annual unit loads of BOD, COD, DOC, SS, TN, NH4^+-N, NO3^--N, TP and PO4^3--P were estimated as 66.9, 133.2, 55.5, 429.8, 36.5, 1.6, 26.9, 1.3 and 0.1 kg/(ha·yr), respectively. In addition, affecting parameters on the EMCs were investigated by statistic analysis of the field data. As a result, significant correlations with precipitation, rainfall intensity, and total runoff flows were found in most constituents.展开更多
This study develops an empirical approach that underlines the effect of land use mix and development grain on pedestrian movement in the streets and public spaces of urban neighborhoods.The study begins with the end i...This study develops an empirical approach that underlines the effect of land use mix and development grain on pedestrian movement in the streets and public spaces of urban neighborhoods.The study begins with the end in mind;it compares two urban sectors in Abu Dhabi city with broadly recognized contrasting levels of pedestrian movement.The research works backward to identify the combination of built environment attributes that result in differing levels of pedestrian activity between the eastern and western sectors of Abu Dhabi city center.Using Geographic Information Systems maps/data files,direct observations,and field metrics,the study computes various indices related to land use mix,density,and street connectivity for Abu Dhabi central business district.The findings of this study highlight the land use,spatial and street network configurations that enhance pedestrian activity in urban centers.From a local perspective,the research outcome would inform future visions aimed at transforming the city of Abu Dhabi into a global metropolis that provides its citizens and visitors with unique and vibrant urban settings conducive to intra-and inter-neighborhood walkability.展开更多
The study aims at exploring the applicability and limitations of domestic and foreign methods for measuring the function mixing of urban land use,and sorting out various classic measurement methods according to the lo...The study aims at exploring the applicability and limitations of domestic and foreign methods for measuring the function mixing of urban land use,and sorting out various classic measurement methods according to the logic of “conceptual reflection–characteristics comparison–limitation analysis.” The study shows that:① the connotation and types of mixed land use functions are still controversial at home and abroad;② there is a lack of research on measurement methods in China;③ for medium and micro-scale planning,current measurement methods cannot fully reflect the differences in the degree of mixing caused by the planar and three-dimensional layout of building functions within the grid;④ the measurement methods for refined planning governance should improve the measurement model in terms of the number of functional types and the mixed layout of various functions in the horizontal and vertical directions at the medium and micro-scales,and improve its accuracy of the measurement results of a single grid and the whole area.展开更多
基金supported by the National Institute of Environmental Research,Korea
文摘The aim of this study was to determine the unit load of NPS (non-point source) pollutants including organic variables such as BOD (biochemical oxygen demand), COD (chemical oxygen demand) and DOC (dissolved organic carbon), nitrogen and phosphorus constituents, and suspended solids (SS) and their event mean concentration (EMC) of runoff flows from a water-shed of mixed forest land use by intensive field experiments. Field monitoring for continuous measurements of rainfall, flow, and water quality was conducted over 12 storm events during 2008-2009 using automated and manual sampling methods. The EMCs of individual runoff event were estimated for each water quality constituent based on the flow rate and concentration data of runoff discharge. The average EMCs of BOD, COD, DOC, SS, TN (total nitrogen), NH4^+-N, NO3^--N, TP (total phosphorus), PO4^3-P from the mixed forest land were 1.794, 3.498, 1.462, 10.269, 0.862, 0.044, 0.634, 0.034, and 0.005 mg/L, respectively. The annual unit loads of BOD, COD, DOC, SS, TN, NH4^+-N, NO3^--N, TP and PO4^3--P were estimated as 66.9, 133.2, 55.5, 429.8, 36.5, 1.6, 26.9, 1.3 and 0.1 kg/(ha·yr), respectively. In addition, affecting parameters on the EMCs were investigated by statistic analysis of the field data. As a result, significant correlations with precipitation, rainfall intensity, and total runoff flows were found in most constituents.
文摘This study develops an empirical approach that underlines the effect of land use mix and development grain on pedestrian movement in the streets and public spaces of urban neighborhoods.The study begins with the end in mind;it compares two urban sectors in Abu Dhabi city with broadly recognized contrasting levels of pedestrian movement.The research works backward to identify the combination of built environment attributes that result in differing levels of pedestrian activity between the eastern and western sectors of Abu Dhabi city center.Using Geographic Information Systems maps/data files,direct observations,and field metrics,the study computes various indices related to land use mix,density,and street connectivity for Abu Dhabi central business district.The findings of this study highlight the land use,spatial and street network configurations that enhance pedestrian activity in urban centers.From a local perspective,the research outcome would inform future visions aimed at transforming the city of Abu Dhabi into a global metropolis that provides its citizens and visitors with unique and vibrant urban settings conducive to intra-and inter-neighborhood walkability.
基金Supported by the Fund:2019 Project,National Key R&D Program of China(No.2019YFD1100804)。
文摘The study aims at exploring the applicability and limitations of domestic and foreign methods for measuring the function mixing of urban land use,and sorting out various classic measurement methods according to the logic of “conceptual reflection–characteristics comparison–limitation analysis.” The study shows that:① the connotation and types of mixed land use functions are still controversial at home and abroad;② there is a lack of research on measurement methods in China;③ for medium and micro-scale planning,current measurement methods cannot fully reflect the differences in the degree of mixing caused by the planar and three-dimensional layout of building functions within the grid;④ the measurement methods for refined planning governance should improve the measurement model in terms of the number of functional types and the mixed layout of various functions in the horizontal and vertical directions at the medium and micro-scales,and improve its accuracy of the measurement results of a single grid and the whole area.