Guiyang is a famous tourist city located in southwestern China. In this study, dust from eleven residential areas, seven city squares, and nine schools was collected to measure the heavy metal levels and evaluate its ...Guiyang is a famous tourist city located in southwestern China. In this study, dust from eleven residential areas, seven city squares, and nine schools was collected to measure the heavy metal levels and evaluate its risk. At each sampling site, 4–5 sub-samples were taken as a bulk sample. All samples were air-dried, ground, passed through a 0.105 mm nylon sieve, digested with HNO3-HClO4 to determine the concentrations of Cd, Cu, Ni, Pb and Zn by ICP-MS, and digested with 1:1 aqua regia to determine As by AFS. The results show that the concentrations of As, Cd, Cu, Ni, Pb and Zn in dust of Guiyang City follow normal distribution with means of 16.1, 1.54, 138, 47.7, 129 and 479 mg/kg, respectively. Levels of As, Cd, Cu, Ni, Pb and Zn exceed the background level of soil in Guizhou Province by 33%, 96%, 100%, 78%, 96%, and 100%, respectively. Cd, Cu, Pb and Zn are heavily accumulated in dust of living areas with accumulation factors of 4.10, 5.12, 4.12 and 5.51, respectively. City square possesses the highest geometric means of As, Cd, Cu, Pb, and Zn. The risks of heavy metal exposure to teenagers are not obvious and in an order of As>Pb>Cu>Ni>Zn(Cd).展开更多
Based on the constitution identification of the urbanization economic costs,econometric model of urbanization economic costs is constructed from four aspects of the investment cost in employment opportunities,the inve...Based on the constitution identification of the urbanization economic costs,econometric model of urbanization economic costs is constructed from four aspects of the investment cost in employment opportunities,the investment cost in urban land use,the investment cost in urban infrastructure,and the investment cost in urban management.Taking Guiyang City as an example,economic cost for each additional urban population in Guiyang City is measured under the current level of social and economic development.Capital requirement for the urban development of Guiyang City in the next 10 years is forecasted.And it is pointed out that there will be significant financing gap in the sustainable development and urbanization process of Guiyang City in future,which provides the basis for the development speed and the reasonable goals of urban sustainable development in future.展开更多
Sixty-two soil samples collected from different functional zones of Guiyang were analyzed for total con-centrations and sequential extraction of Cr,Cu,Pb,Zn and Cd by ICP spectrometry. The average total concentrations...Sixty-two soil samples collected from different functional zones of Guiyang were analyzed for total con-centrations and sequential extraction of Cr,Cu,Pb,Zn and Cd by ICP spectrometry. The average total concentrations of Cr,Cu,Pb,Zn and Cd in the soils of Guiyang were 92.9,51.6,44.1,139.3 and 0.28 mg/kg,respectively. The soils have been polluted by Cr,Cu,Pb,Zn and Cd to some extent in comparison with the background values of Guiyang. Significant differences were recognized in the concentrations of Cr,Cu,Pb,Zn and Cd in different functional zones. As for the sequential extraction,Cr,Cu and Zn were present mainly in the residual fraction,and Pb was present mainly in the oxidizable fraction. The reducible fraction of Cd accounts for 47.5%,and the residual fraction is lowest. The mobility and bioavailability of heavy metals follow the order of Cd>Pb>Cu>Cr>Zn.展开更多
The aim of this study is to shed light on the hydrogeochemical characteristics of karst underground waters at shallow depth in Guiyang City, Guizhou Province with an emphasis on the geochemistry of major elements. Gui...The aim of this study is to shed light on the hydrogeochemical characteristics of karst underground waters at shallow depth in Guiyang City, Guizhou Province with an emphasis on the geochemistry of major elements. Guiyang City bears abundant underground waters and it is also an important representative of the karst areas throughout the world. Ca+{2+} and Mg+{2+} are the dominant cations, accounting for 81%-{99.7%} of the total, and HCO+--3 and SO+{2-}-4 are the dominant anions. Weathering of limestones and dolostones is the most important factor controlling the hydrogeochemistry of underground waters, and weathering of sulfate and evaporite rocks is less important. Moreover, the precipitation and human activities also have a definite influence on the hydrogeochemistry of underground waters in the region studied.展开更多
In the context of park city construction,urban street space system and scene construction are the most important forms of presentation of value transformation framework.Most of the outdoor activities of urban resident...In the context of park city construction,urban street space system and scene construction are the most important forms of presentation of value transformation framework.Most of the outdoor activities of urban residents are completed in the urban street space which constitutes various scenes.Scene construction not only includes the material space as the carrier,but also includes the behaviors and activities of the participants and the time and path of “program setting”,as well as the opening and closing of events.Scene construction is an effective approach explored during the construction of the park city demonstration area,which is currently practicing the new development concept.However,there have been no reports on the specific theories,methods,processes,and systems of scene construction,especially for the lack of pattern summary and method induction for program setting in scene construction.Therefore,from the perspective of building a park city demonstration area that implements the new development concept,the paper discusses the concept,connotation,process and modularity of the program setting of street space scene construction,in order to provide certain theoretical basis for the scene construction and “value transformation” of park city street space system.展开更多
Institutional development and the substantial governance outcomes have continued to be a big theme in Political Science.This paper focuses on partnership practices in public works construction and decision-making case...Institutional development and the substantial governance outcomes have continued to be a big theme in Political Science.This paper focuses on partnership practices in public works construction and decision-making cases in city and urban settings(as a socio-political environment).In these settings,the management of policy regarding space and time should conduct on understandings of the various dimensions of institutional settings.We are going to emphasize institution and coordination in the public policy process.So,this paper attempted to describe chronological restrictions that were generated by long-term interactions and institutional transformation’s patterns from a historical institutional view.As much as possible,we have analyzed the following micro-institutional experiments,participatory governance(Case I)and public works executions(Cases II and III)to show the institutional development patterns precisely.展开更多
Based on the survey of 154 farmers in Guiyang City, we analyze the basic situation of building of grass-roots agricultural technology extension system in Guiyang City. Then we point out some problems in the building o...Based on the survey of 154 farmers in Guiyang City, we analyze the basic situation of building of grass-roots agricultural technology extension system in Guiyang City. Then we point out some problems in the building of grass-roots agricultural technology extension system in Guiyang City: the function of grass-roots agricultural technology extension center weakens; the content of agricultural technology extension is difficult to adapt to farmers' needs for technology; the extension mode of agricultural technology departments does not adapt to the needs of modern agriculture. In order to perfect the building of grass-roots agricultural technology extension system, the countermeasures and recommendations are put forth as follows: strengthening the input of funds, and ensuring that the basic work of public welfare agricultural technology extension is smoothly carried out; innovating upon the system, and improving the function of grass-roots agricultural technology extension center; implementing management on agricultural technology extension personnel's performance, and promoting the extension efficiency; strengthening the building of extension team in rural areas, and cultivating high-quality agricultural technology extension personnel; exploring the advanced service mode to meet farmers' needs.展开更多
基金supported by National Natural Science Foundation of China(41161079)
文摘Guiyang is a famous tourist city located in southwestern China. In this study, dust from eleven residential areas, seven city squares, and nine schools was collected to measure the heavy metal levels and evaluate its risk. At each sampling site, 4–5 sub-samples were taken as a bulk sample. All samples were air-dried, ground, passed through a 0.105 mm nylon sieve, digested with HNO3-HClO4 to determine the concentrations of Cd, Cu, Ni, Pb and Zn by ICP-MS, and digested with 1:1 aqua regia to determine As by AFS. The results show that the concentrations of As, Cd, Cu, Ni, Pb and Zn in dust of Guiyang City follow normal distribution with means of 16.1, 1.54, 138, 47.7, 129 and 479 mg/kg, respectively. Levels of As, Cd, Cu, Ni, Pb and Zn exceed the background level of soil in Guizhou Province by 33%, 96%, 100%, 78%, 96%, and 100%, respectively. Cd, Cu, Pb and Zn are heavily accumulated in dust of living areas with accumulation factors of 4.10, 5.12, 4.12 and 5.51, respectively. City square possesses the highest geometric means of As, Cd, Cu, Pb, and Zn. The risks of heavy metal exposure to teenagers are not obvious and in an order of As>Pb>Cu>Ni>Zn(Cd).
基金Supported by the Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-year Plan Period (2006BAJ14B4-02)
文摘Based on the constitution identification of the urbanization economic costs,econometric model of urbanization economic costs is constructed from four aspects of the investment cost in employment opportunities,the investment cost in urban land use,the investment cost in urban infrastructure,and the investment cost in urban management.Taking Guiyang City as an example,economic cost for each additional urban population in Guiyang City is measured under the current level of social and economic development.Capital requirement for the urban development of Guiyang City in the next 10 years is forecasted.And it is pointed out that there will be significant financing gap in the sustainable development and urbanization process of Guiyang City in future,which provides the basis for the development speed and the reasonable goals of urban sustainable development in future.
基金financially supported by the Ministry of Science and Technology of China through National Program on Key Basic Research Project (Grant No.2006 CB403200)
文摘Sixty-two soil samples collected from different functional zones of Guiyang were analyzed for total con-centrations and sequential extraction of Cr,Cu,Pb,Zn and Cd by ICP spectrometry. The average total concentrations of Cr,Cu,Pb,Zn and Cd in the soils of Guiyang were 92.9,51.6,44.1,139.3 and 0.28 mg/kg,respectively. The soils have been polluted by Cr,Cu,Pb,Zn and Cd to some extent in comparison with the background values of Guiyang. Significant differences were recognized in the concentrations of Cr,Cu,Pb,Zn and Cd in different functional zones. As for the sequential extraction,Cr,Cu and Zn were present mainly in the residual fraction,and Pb was present mainly in the oxidizable fraction. The reducible fraction of Cd accounts for 47.5%,and the residual fraction is lowest. The mobility and bioavailability of heavy metals follow the order of Cd>Pb>Cu>Cr>Zn.
文摘The aim of this study is to shed light on the hydrogeochemical characteristics of karst underground waters at shallow depth in Guiyang City, Guizhou Province with an emphasis on the geochemistry of major elements. Guiyang City bears abundant underground waters and it is also an important representative of the karst areas throughout the world. Ca+{2+} and Mg+{2+} are the dominant cations, accounting for 81%-{99.7%} of the total, and HCO+--3 and SO+{2-}-4 are the dominant anions. Weathering of limestones and dolostones is the most important factor controlling the hydrogeochemistry of underground waters, and weathering of sulfate and evaporite rocks is less important. Moreover, the precipitation and human activities also have a definite influence on the hydrogeochemistry of underground waters in the region studied.
文摘In the context of park city construction,urban street space system and scene construction are the most important forms of presentation of value transformation framework.Most of the outdoor activities of urban residents are completed in the urban street space which constitutes various scenes.Scene construction not only includes the material space as the carrier,but also includes the behaviors and activities of the participants and the time and path of “program setting”,as well as the opening and closing of events.Scene construction is an effective approach explored during the construction of the park city demonstration area,which is currently practicing the new development concept.However,there have been no reports on the specific theories,methods,processes,and systems of scene construction,especially for the lack of pattern summary and method induction for program setting in scene construction.Therefore,from the perspective of building a park city demonstration area that implements the new development concept,the paper discusses the concept,connotation,process and modularity of the program setting of street space scene construction,in order to provide certain theoretical basis for the scene construction and “value transformation” of park city street space system.
文摘Institutional development and the substantial governance outcomes have continued to be a big theme in Political Science.This paper focuses on partnership practices in public works construction and decision-making cases in city and urban settings(as a socio-political environment).In these settings,the management of policy regarding space and time should conduct on understandings of the various dimensions of institutional settings.We are going to emphasize institution and coordination in the public policy process.So,this paper attempted to describe chronological restrictions that were generated by long-term interactions and institutional transformation’s patterns from a historical institutional view.As much as possible,we have analyzed the following micro-institutional experiments,participatory governance(Case I)and public works executions(Cases II and III)to show the institutional development patterns precisely.
文摘Based on the survey of 154 farmers in Guiyang City, we analyze the basic situation of building of grass-roots agricultural technology extension system in Guiyang City. Then we point out some problems in the building of grass-roots agricultural technology extension system in Guiyang City: the function of grass-roots agricultural technology extension center weakens; the content of agricultural technology extension is difficult to adapt to farmers' needs for technology; the extension mode of agricultural technology departments does not adapt to the needs of modern agriculture. In order to perfect the building of grass-roots agricultural technology extension system, the countermeasures and recommendations are put forth as follows: strengthening the input of funds, and ensuring that the basic work of public welfare agricultural technology extension is smoothly carried out; innovating upon the system, and improving the function of grass-roots agricultural technology extension center; implementing management on agricultural technology extension personnel's performance, and promoting the extension efficiency; strengthening the building of extension team in rural areas, and cultivating high-quality agricultural technology extension personnel; exploring the advanced service mode to meet farmers' needs.
