Night tourism often involves a large number of lighting facilities,which consume a large amount of energy.Therefore,one of the unique low energy consumption natural ecological tourism activities—firefly night tour ha...Night tourism often involves a large number of lighting facilities,which consume a large amount of energy.Therefore,one of the unique low energy consumption natural ecological tourism activities—firefly night tour has attracted attention and become an important breakthrough point for night tourism in tourist destinations.In this paper,Guangzhou firefly night tour project is taken as the research object.Based on the comprehensive economic,environmental,and socio-cultural benefits brought by the development of firefly night tour,the resources distribution,current development status,and existing problems of firefly night tour in Guangzhou are analyzed,and its high-quality development paths are proposed from three levels:government,industry,and tourist.The aim is to explore a new model for the economic development of Guangzhou night tour,boosting the transformation and upgrading of the night tourism economy,while also providing reference ideas and value for the development of night tourism economy in other tourist destinations.展开更多
Through the ICH Brand Summit,the ICH participants actively grasp the ICH inheritance rules,adhere to integrity and innovation,adapt to the consumption concept changes and consumption structure upgrading,and introduce ...Through the ICH Brand Summit,the ICH participants actively grasp the ICH inheritance rules,adhere to integrity and innovation,adapt to the consumption concept changes and consumption structure upgrading,and introduce modern business concepts,management methods,business models,and communication methods,so as to showcase the unique charm of China's ICH development and inheritance to theworld.展开更多
Linguistic landscape has become an emerging research topic in sociolinguistics due to the development of urban linguistic landscape.Based on the development of linguistic landscape in TaiKoo Hui,its diverse characteri...Linguistic landscape has become an emerging research topic in sociolinguistics due to the development of urban linguistic landscape.Based on the development of linguistic landscape in TaiKoo Hui,its diverse characteristics are analyzed,and the language signs,usage,and codes are summarized.It is found that there is poor transmission effect of multilingual landscape information and improper use of linguistic landscape in TaiKoo Hui.This paper concludes that the linguistic landscape of Taikoo Hui can be optimized from two aspects to enhance its attractiveness and competitiveness,including improving the informational function of foreign language signs and regulating the use of linguistic landscape.展开更多
The chemical characteristics(water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode.Most of the chemical species in PM2.5 showed significant difference between...The chemical characteristics(water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode.Most of the chemical species in PM2.5 showed significant difference between normal and haze days.The highest contributors to PM2.5 were organic carbon(OC),nitrate,and sulfate in haze days and were OC,sulfate,and elemental carbon(EC) in normal days.The concentrations of secondary species such as,NO3^-,SO4^2-,and NH4^+ in haze days were 6.5,3.9,and 5.3 times higher than those in normal days,respectively,while primary species(EC,Ca^2+,K^+) show similar increase from normal to haze days by a factor about 2.2-2.4.OC/EC ratio ranged from 2.8 to 6.2 with an average of 4.7 and the estimation on a minimum OC/EC ratio showed that SOC(secondary organic carbon) accounted more than 36.6% for the total organic carbon in haze days.The significantly increase in the secondary species(SOC,NO3^-,SO4^2-,and NH4^+),especially in NO3^-,caused the worst air quality in this region.Simultaneously,the result illustrated that the serious air pollution in haze episodes was strongly correlated with the meteorological conditions.During the sampling periods,air pollution and visibility had a good relationship with the air mass transport distance;the shorter air masses transport distance,the worse air quality and visibility in Guangzhou,indicating the strong domination of local sources contributing to haze formation.High concentration of the secondary aerosol in haze episodes was likely due to the higher oxidation rates of sulfur and nitrogen species.展开更多
On the basis of the reported air quality index (API) and air pollutant monitoring data provided by the Guangzhou Environment Monitoring Stations over the last twenty-five years, the characteristics of air quality, p...On the basis of the reported air quality index (API) and air pollutant monitoring data provided by the Guangzhou Environment Monitoring Stations over the last twenty-five years, the characteristics of air quality, prominent pollutants, and variation of the average annual concentrations of SOE, NOE, total suspended particulate (TSP), fine particulates (PM10), CO and dustfall in Guangzhou City were analyzed. Results showed that TSP was the prominent pollutant in the ambient air environment of Guangzhou City. Of the prominent pollutants, TSP accounted for nearly 62%, SOE 12.3%, and NOx 6.4%, respectively. The average API of Guangzhou over 6 years was higher than that of Beijing, Tianjin, Nanjing, Hangzhou, Suzhou and Shanghai, and lower than that of Shenzhen, Zhuhai and Shantou. Concentrations of air pollutants have shown a downward trend in recent years, but they are generally worse than ambient air quality standards for USA, Hong Kong and EU. SOE and NOx pollution were still serious, impling that waste gas pollution from all kinds of vehicles had become a significant problem for environmental protection in Guangzhou. The possible causes of worsening air quality were also discussed in this paper.展开更多
The plant biomass and net primary production(NPP) of urban vegetation in Guangzhou were estimated by dimension analysis, tree truck volume, and harvest methods as well as relationship between biomass and NPP and so on...The plant biomass and net primary production(NPP) of urban vegetation in Guangzhou were estimated by dimension analysis, tree truck volume, and harvest methods as well as relationship between biomass and NPP and so on. The biomass and NPP were respectively 2875150t and 1058122 t/a. They were respectively 392495t and 64948 t/a in the built-up area and 2482655t and 993147 t/a in the unbuilt-up area. It would make plant biomass, especially NPP decline obviously, if the unbuilt-up area were changed to the built-up area. The carbon content of plant was 1328649 for the total and 13.78 t/hm 2 for the mean, and amounts of carbon fixed and oxygen made by urban vegetation were respectively 4.80 t/(hm 2·a) and 12.79 t/(hm 2·a) for the mean and 462624 t/a and 1232430 t/a for the total, which were equal to 1.45 times and 1.04 times of those by human breathing. However, they were only equal to 7.61% and 4.97% of amount of carbon released and oxygen consumption in urban Guangzhou. The biomass and NPP of urban vegetation in Guangzhou only corresponded to 7.8% and 47.3% of those of southern subtropical evergreen broad-leaf forest in Dinghu Mountain. Therefore, the roles of Guangzhou urban vegetation in balance of carbon and oxygen would be increased greatly if it could be conserved and improved in some way.展开更多
Polycyclic aromatic hydrocarbons (PAHs) were measured in precipitation from March to August 2005 in Guangzhou, South China. Fourteen PAHs were studied, and their total concentrations varied from 616.6 to 3486.7 ng/L...Polycyclic aromatic hydrocarbons (PAHs) were measured in precipitation from March to August 2005 in Guangzhou, South China. Fourteen PAHs were studied, and their total concentrations varied from 616.6 to 3486.7 ng/L in dissolved phase and from 403.8 to 3125.5 ng/L in particulate phase. The estimated deposition loading of PAHs was 3568 ug/m^2 during the monitoring period. The deposition of PAHs was a potential source for Pearl River comparing with the contents of surface water. In addition, the high concentration in precipitation here implied that PAHs pollution was a potential environmental problem in Guangzhou. Most precipitation concentrations of PAHs in March (the last month in winter in Guangzhou) were higher than in the other months (in rainy season). PAHs inclined to be adsorbed to particulate phase with the increase of molecular weight in rainwater. Combustion of fossil fuel and biomass might be the major source of PAHs, while the direct leakage or volatilization from petroleum products might be insignificant.展开更多
AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free ...AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free and non-free colonoscopy districts was used to collect information on demographic characteristics, health behaviours, the intention of the cancer screenings and willingness to pay for colorectal cancer screening. A total of 1243 participants who took part in the pre-screening for colorectal cancer in Guangzhou were collected in the study. Categorical data were compared using the χ~2 test to analyse significant differences. Non-conditional logistic regression and multi-class logistic regression were also performed for multivariate analysis and to estimate the odds ratios.RESULTS The percentage of participants willing to pay for colorectal cancer screening was 91.7%. "Unnecessary" was the dominant reason that participants gave for their unwillingness, accounting for 63.1%. Of those who were willing to pay, 29.2%, 20.7%, 14.8%, 13.0% and 22.4% of participants were willing to pay less than $100, $100-$199, $200-299, $300-$399 and more than $400, respectively. Non-logistic regression analysis showed that respondents who were male, had a high level of education, were from the family with more children/older to raise, and accepted colorectal cancer screening were willing to pay for this screening. Multi-class logistic regression analysis showed that respondents with higher annual household income per capita, from government and private enterprises, government agency/institution and peasants, and less family medical expenditure were willing to pay more.CONCLUSION Willingness to pay for colorectal cancer screening in Guangzhou is high, but the amount of willing to pay is not much.展开更多
The compositions, patches and landscape heteorogentity of Guangzhou urban vegetation are studied by using the principles of landscape ecology in this paper. The results showed that the area of urban vegetation was 26...The compositions, patches and landscape heteorogentity of Guangzhou urban vegetation are studied by using the principles of landscape ecology in this paper. The results showed that the area of urban vegetation was 26901 4hm 2, and the distribution of vegetation types and regional vegetation coverage were uneven. The patch areas of vegetation were large in scenery vegetation and shelter vegetation, and small in street corner vegetation and small garden vegetation. Most of patches fell in range between 100 and 10000 m 2. Only 1.13% of patches were larger than 1000000 m 2. Structure features of vegetation landscape in old urban areas were small patch, high scattering degree, high diversity, random distribution of vegetation patches and high heterogeneity. In new urban areas, the features were big patches, fine planning, medium landscape heterogeneity. Some suggestions are made according to landscape character of urban vegetation in Guangzhou.展开更多
Ecological methodology plus negative binomial regression were used to identify dengue fever (DF) epidemiological status and its relationship with meteorological variables. From 2007 to 2012, annual incidence rate of...Ecological methodology plus negative binomial regression were used to identify dengue fever (DF) epidemiological status and its relationship with meteorological variables. From 2007 to 2012, annual incidence rate of DF in Guangzhou was 0.33, 0.11, 0.15, 0.64, 0.45, and 1.34 (per 100 000) respectively, showing an increasing trend. Each 1℃ rise of temperature corresponded to an increase of 10.23% (95% CI 7.68% to 12.83%) in the monthly number of DF cases, whereas l hPa rise of atmospheric pressure corresponded to a decrease in the number of cases by 5.14% (95% CI: 7.10%-3.14%). Likewise, each one meter per second rise in wind velocity led to an increase by 43.80% or 107.53%, and one percent rise of relative humidity led to an increase by 2.04% or 2.19%.展开更多
Mobile information and communication technologies(MICTs) have fully penetrated everyday life in smart societies;this has greatly compressed time, space, and distance, and consequently, reshaped residents’ travel beha...Mobile information and communication technologies(MICTs) have fully penetrated everyday life in smart societies;this has greatly compressed time, space, and distance, and consequently, reshaped residents’ travel behaviour patterns. As a new mode of shared mobility, the sharing bicycle offers a variety of options for the daily travel of urban residents. Extant studies have mainly examined the travel characteristics and influencing factors of public bicycles with piles, while the travel patterns for sharing bicycles and their driving mechanisms have been largely ignored. Using one week’s travel data for Mobike, this study investigated the spatial and temporal distribution patterns of sharing bicycle travel behaviours in the central urban area of Guangzhou, China;furthermore, it identified the influences of built environment density factors on sharing bicycle travel behaviours based on the geographically weighted regression method. Obvious morning and evening peaks were observed in the sharing bicycle travel patterns for both weekdays and weekends. The old urban area, which had a high degree of mixed function, dense road networks, and cycling-friendly built environments, was the main travel area that attracted sharing bicycles on both weekdays and weekends. Furthermore, factors including the point of interest(POI) for the density of public transport stations, the functional mixing degree, and the density of residential POIs significantly affected residents’ travel behaviours. These findings could enrich discourse regarding shared mobility with a Chinese case characterised by rapidly developing MICTs and also provide references to local authorities for improving slow traffic environments.展开更多
The concept of urban green space system planning was proposed after analyzing the background of compiling Guangzhou green space system planning and current situation of local green spaces,i.e. design landscape pattern...The concept of urban green space system planning was proposed after analyzing the background of compiling Guangzhou green space system planning and current situation of local green spaces,i.e. design landscape pattern of Guangzhou City during urban agglomeration of the Pearl River Delta,and highlight Lingnan cultures(Lingnan refers to south of the Five Ridges) and features of "Flower City"(another name of Guangzhou). Key points of planning are protecting ecological barriers in the north,improving urban garden structure in the center,using wetland reasonably in the south,to maintain integrality and continuity of the landscape pattern.展开更多
Understanding the spatiotemporal patterns of three-dimensional urban forms,especially building height,can have important implications for improving urban air quality and mitigating the urban heat island effect by opti...Understanding the spatiotemporal patterns of three-dimensional urban forms,especially building height,can have important implications for improving urban air quality and mitigating the urban heat island effect by optimizing urban planning and management policies.This study investigated building height evolution and its influencing factors over approximately half a century(1960–2017)in Guangzhou,China.The results indicated that the logarithmic declines in height,quantity,and area of urban buildings followed Zapf’s law,which restricts the three-dimensional shape of the urban form.The urban building height decreased from the center to the periphery of the city and decreased with decreasing altitude and increasing distance from main roads.These characteristics constituted the three main spatial differentiation rules of building height in the central district of Guangzhou,and all exhibited a logarithmic decrease,which gradually strengthened over time.The development of a double-layered height structure of low-rise and high-rise buildings between 1990 and 2017 was a notable manifestation of the increase in vertical urban height over time.The three factors of city center,altitude,and accessibility,which represent centrality,low relief,proximity to water,and proximity to road networks,highlighted the roles of traffic accessibility and commercial attraction in building height evolution.The importance of location macroscopically depends on the combined effect of the geographical pattern,urban planning,and market forces of cities located on a plain near hill or by a river.The principle of profit orientation restricted spatiotemporal building height patterns.展开更多
Based on the ETM remote sensing images of Guangzhou City in 2014, the spatial distribution results o f three environmental factors including vegetation coverage(NDVI), soil index(vegetation index of bare soil) and sl ...Based on the ETM remote sensing images of Guangzhou City in 2014, the spatial distribution results o f three environmental factors including vegetation coverage(NDVI), soil index(vegetation index of bare soil) and sl ope were obtained. By using comprehensive index method, the normalized environmental factors were weighted and superimposed, and the fi nal evaluation results of ecological environment in Guangzhou City were obtained. The results showed that overall situation of natural ecological environment in Guangzhou was not optimistic, that is, the area of land with bad, moderate, good and superior environment accounted for 59.70%, 35.79%, 4.50% and around 0.01% of total area of land in Guangzhou City respectively. Ecological environment was generally poor in the central urban districts in the south of Guangzhou City, while it was relatively better in the north and northeast. Attaching importance to the constr uction of greenbelts and greenways is an effective way to improve regional environmental quality and natural ecological e nvironment level.展开更多
Every 6 seconds,someone dies from cancer somewhere in the world.Every 13 seconds,a cancer patient dies in China.Cancer is currently the biggest threat to life around the world and a critical burden to China.To address...Every 6 seconds,someone dies from cancer somewhere in the world.Every 13 seconds,a cancer patient dies in China.Cancer is currently the biggest threat to life around the world and a critical burden to China.To address this problem,it is especially important for scientists and physicians to remain abreast of cutting edge research and progress in the treatment of this disease.The 3rd Guangzhou International Symposium on Oncology展开更多
In order to find out the distribution characteristics of BTEX in groundwater, which include Benzene, Toluene, Ethylbenzene, p-Xylene, m-Xylene, and o-Xylene, 82 groups of groundwater samples and 10 surface water sampl...In order to find out the distribution characteristics of BTEX in groundwater, which include Benzene, Toluene, Ethylbenzene, p-Xylene, m-Xylene, and o-Xylene, 82 groups of groundwater samples and 10 surface water samples collected from Guangzhou in Guangdong during 2005 to 2008 were tested by gas chromatography and mass spectrum(GC/MS). The result showed that the BTEX concentration in groundwater does not exceed the standard. The detection rate of BTEX is 14.63% in groundwater, and the total BTEX concentration is lower than 9.5 μg/L. Of 6 kinds of BTEX, toluene had the highest detection rate(12.20%) and detection value(9.5 μg/L), which was followed by Benzene, with the detection rate of 3.65%, and detection value of 4.9 μg/L respectively; most of samples with BTEX are distributed in Huangpu district, Baiyun district, Huadu district and other industrialized areas; this spatial distribution and urban distribution have obvious consistency. With economic development, plant expansion and population growth led to a large amount of waste water discharge, and infrastructure construction is lagging behind, indicating that rapid urbanization is a major driving force of BTEX in groundwater, and through the analysis of a typical area, it is found that benzene system surface water infiltration was an important source of BTEX in groundwater of Guangzhou.展开更多
Objective High PM2.5 concentration is the main feature of increasing haze in developing states,but information on its microbial composition remains very limited.This study aimed to determine the composition of microbi...Objective High PM2.5 concentration is the main feature of increasing haze in developing states,but information on its microbial composition remains very limited.This study aimed to determine the composition of microbiota in PM2.5 in Guangzhou,a city located in the tropics in China.Methods In Guangzhou,from March 5th to 10th,2016,PM2.5 was collected in middle volume air samplers for 23 h daily.The 16 S rDNA V4 region of the PM2.5 sample extracted DNA was investigated using high-throughput sequence.Results Among the Guangzhou samples,Proteobacteria,Bacteroidetes,Firmicutes,Cyanobacteria,and Actinobacteria were the dominant microbiota accounting for more than 90%of the total microbiota,and Stenotrophomonas was the dominant gram-negative bacteria,accounting for 21.30%–23.57%.We examined the difference in bacterial distribution of PM2.5 between Beijing and Guangzhou at the genus level;Stenotrophomonas was found in both studies,but Escherichia was only detected in Guangzhou.Conclusion In conclusion,the diversity and specificity of microbial components in Guangzhou PM2.5 were studied,which may provide a basis for future pathogenicity research in the tropics.展开更多
Proceeding from the commercial function of Guangzhou urban area, this paper expounds the principles and requirements for choosing commercial location, puts forward the bases to determine the limits of commercial centr...Proceeding from the commercial function of Guangzhou urban area, this paper expounds the principles and requirements for choosing commercial location, puts forward the bases to determine the limits of commercial centres. Thirty major commercial centres, in Guangzhou urban area are classified by means of cluster analysis. The function, size, hierarchy and interconnection of commercial centres of different groups are studied. The paper emphatically analyzes the major characteristics and formation factors of the commercial location of Guangzhou urban area. Finally, to counter some problems in existence, some suggestions are put forward in order to improve the commercial location of Guangzhou urban area.展开更多
Changes in transport are likely to preduce changes in land use, and these long-term effects of transport policy may be of considerable potential importance. There is a growing movement, "The New Urbanism", w...Changes in transport are likely to preduce changes in land use, and these long-term effects of transport policy may be of considerable potential importance. There is a growing movement, "The New Urbanism", which seeks to reconnect transport with land use and in particular to eslablish transitoriented development where higher-density,mixed-use areas are built around high-quality transit systems. Based on analysis on development and Pattern of urban transport inGuangzhou, this paper researches composition of urban transportation and struclure of travel pattern. The urban transport system development and change in urban form as well as change in land use are closely related. The urban transport, system required and promnoted by the high-density land-use pattern. There are many problems in the urban transportation and land-use, one of the resolving is integration of urban transport planning and land-use planning.展开更多
基金the 14th Five-year Plan Project for the Development of Philosophy and Social Sciences of Guangzhou(2023GZGJ83)the 2021 General University Key Scientific Research Project of Department of Education of Guangdong Province(2021ZDZX4104)+1 种基金Project of Guangdong Provincial Department of Education(2021GDJG600,2021ZQXY45)the Guangdong Ploytechnic of Industry and Commerce Project(2023-SKJ-20).
文摘Night tourism often involves a large number of lighting facilities,which consume a large amount of energy.Therefore,one of the unique low energy consumption natural ecological tourism activities—firefly night tour has attracted attention and become an important breakthrough point for night tourism in tourist destinations.In this paper,Guangzhou firefly night tour project is taken as the research object.Based on the comprehensive economic,environmental,and socio-cultural benefits brought by the development of firefly night tour,the resources distribution,current development status,and existing problems of firefly night tour in Guangzhou are analyzed,and its high-quality development paths are proposed from three levels:government,industry,and tourist.The aim is to explore a new model for the economic development of Guangzhou night tour,boosting the transformation and upgrading of the night tourism economy,while also providing reference ideas and value for the development of night tourism economy in other tourist destinations.
文摘Through the ICH Brand Summit,the ICH participants actively grasp the ICH inheritance rules,adhere to integrity and innovation,adapt to the consumption concept changes and consumption structure upgrading,and introduce modern business concepts,management methods,business models,and communication methods,so as to showcase the unique charm of China's ICH development and inheritance to theworld.
文摘Linguistic landscape has become an emerging research topic in sociolinguistics due to the development of urban linguistic landscape.Based on the development of linguistic landscape in TaiKoo Hui,its diverse characteristics are analyzed,and the language signs,usage,and codes are summarized.It is found that there is poor transmission effect of multilingual landscape information and improper use of linguistic landscape in TaiKoo Hui.This paper concludes that the linguistic landscape of Taikoo Hui can be optimized from two aspects to enhance its attractiveness and competitiveness,including improving the informational function of foreign language signs and regulating the use of linguistic landscape.
基金supported by the National Excellent Youth Foundation of China (No. 20625722)the China Postdoctoral Science Foundation (No. 20080430396)
文摘The chemical characteristics(water-soluble ions and carbonaceous species) of PM2.5 in Guangzhou were measured during a typical haze episode.Most of the chemical species in PM2.5 showed significant difference between normal and haze days.The highest contributors to PM2.5 were organic carbon(OC),nitrate,and sulfate in haze days and were OC,sulfate,and elemental carbon(EC) in normal days.The concentrations of secondary species such as,NO3^-,SO4^2-,and NH4^+ in haze days were 6.5,3.9,and 5.3 times higher than those in normal days,respectively,while primary species(EC,Ca^2+,K^+) show similar increase from normal to haze days by a factor about 2.2-2.4.OC/EC ratio ranged from 2.8 to 6.2 with an average of 4.7 and the estimation on a minimum OC/EC ratio showed that SOC(secondary organic carbon) accounted more than 36.6% for the total organic carbon in haze days.The significantly increase in the secondary species(SOC,NO3^-,SO4^2-,and NH4^+),especially in NO3^-,caused the worst air quality in this region.Simultaneously,the result illustrated that the serious air pollution in haze episodes was strongly correlated with the meteorological conditions.During the sampling periods,air pollution and visibility had a good relationship with the air mass transport distance;the shorter air masses transport distance,the worse air quality and visibility in Guangzhou,indicating the strong domination of local sources contributing to haze formation.High concentration of the secondary aerosol in haze episodes was likely due to the higher oxidation rates of sulfur and nitrogen species.
基金Project supported by the National Natural Science Foundation of China (No. 30270282)the Key Project of Chinese Education Ministry (No. 704037)the Special Invited Professor Foundation of Guangdong Province.
文摘On the basis of the reported air quality index (API) and air pollutant monitoring data provided by the Guangzhou Environment Monitoring Stations over the last twenty-five years, the characteristics of air quality, prominent pollutants, and variation of the average annual concentrations of SOE, NOE, total suspended particulate (TSP), fine particulates (PM10), CO and dustfall in Guangzhou City were analyzed. Results showed that TSP was the prominent pollutant in the ambient air environment of Guangzhou City. Of the prominent pollutants, TSP accounted for nearly 62%, SOE 12.3%, and NOx 6.4%, respectively. The average API of Guangzhou over 6 years was higher than that of Beijing, Tianjin, Nanjing, Hangzhou, Suzhou and Shanghai, and lower than that of Shenzhen, Zhuhai and Shantou. Concentrations of air pollutants have shown a downward trend in recent years, but they are generally worse than ambient air quality standards for USA, Hong Kong and EU. SOE and NOx pollution were still serious, impling that waste gas pollution from all kinds of vehicles had become a significant problem for environmental protection in Guangzhou. The possible causes of worsening air quality were also discussed in this paper.
基金TheNationalNaturalScienceFoundationofChina(No .495 710 64 )andGuangdongEnvironmentalProtectionBureau (No .1999 15 )
文摘The plant biomass and net primary production(NPP) of urban vegetation in Guangzhou were estimated by dimension analysis, tree truck volume, and harvest methods as well as relationship between biomass and NPP and so on. The biomass and NPP were respectively 2875150t and 1058122 t/a. They were respectively 392495t and 64948 t/a in the built-up area and 2482655t and 993147 t/a in the unbuilt-up area. It would make plant biomass, especially NPP decline obviously, if the unbuilt-up area were changed to the built-up area. The carbon content of plant was 1328649 for the total and 13.78 t/hm 2 for the mean, and amounts of carbon fixed and oxygen made by urban vegetation were respectively 4.80 t/(hm 2·a) and 12.79 t/(hm 2·a) for the mean and 462624 t/a and 1232430 t/a for the total, which were equal to 1.45 times and 1.04 times of those by human breathing. However, they were only equal to 7.61% and 4.97% of amount of carbon released and oxygen consumption in urban Guangzhou. The biomass and NPP of urban vegetation in Guangzhou only corresponded to 7.8% and 47.3% of those of southern subtropical evergreen broad-leaf forest in Dinghu Mountain. Therefore, the roles of Guangzhou urban vegetation in balance of carbon and oxygen would be increased greatly if it could be conserved and improved in some way.
基金supported by the Guangdong Natural Science of Foundation (No. 8151065003000004)the National Natural Science Foundation of China (No.20807012), and the GIGCAS (No. IS-1048).
文摘Polycyclic aromatic hydrocarbons (PAHs) were measured in precipitation from March to August 2005 in Guangzhou, South China. Fourteen PAHs were studied, and their total concentrations varied from 616.6 to 3486.7 ng/L in dissolved phase and from 403.8 to 3125.5 ng/L in particulate phase. The estimated deposition loading of PAHs was 3568 ug/m^2 during the monitoring period. The deposition of PAHs was a potential source for Pearl River comparing with the contents of surface water. In addition, the high concentration in precipitation here implied that PAHs pollution was a potential environmental problem in Guangzhou. Most precipitation concentrations of PAHs in March (the last month in winter in Guangzhou) were higher than in the other months (in rainy season). PAHs inclined to be adsorbed to particulate phase with the increase of molecular weight in rainwater. Combustion of fossil fuel and biomass might be the major source of PAHs, while the direct leakage or volatilization from petroleum products might be insignificant.
基金Supported by the Natural Science Foundation of Guangdong Province,No.2016A030313504Guangzhou Science and Technology Program Key Project,No.201707010205
文摘AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free and non-free colonoscopy districts was used to collect information on demographic characteristics, health behaviours, the intention of the cancer screenings and willingness to pay for colorectal cancer screening. A total of 1243 participants who took part in the pre-screening for colorectal cancer in Guangzhou were collected in the study. Categorical data were compared using the χ~2 test to analyse significant differences. Non-conditional logistic regression and multi-class logistic regression were also performed for multivariate analysis and to estimate the odds ratios.RESULTS The percentage of participants willing to pay for colorectal cancer screening was 91.7%. "Unnecessary" was the dominant reason that participants gave for their unwillingness, accounting for 63.1%. Of those who were willing to pay, 29.2%, 20.7%, 14.8%, 13.0% and 22.4% of participants were willing to pay less than $100, $100-$199, $200-299, $300-$399 and more than $400, respectively. Non-logistic regression analysis showed that respondents who were male, had a high level of education, were from the family with more children/older to raise, and accepted colorectal cancer screening were willing to pay for this screening. Multi-class logistic regression analysis showed that respondents with higher annual household income per capita, from government and private enterprises, government agency/institution and peasants, and less family medical expenditure were willing to pay more.CONCLUSION Willingness to pay for colorectal cancer screening in Guangzhou is high, but the amount of willing to pay is not much.
文摘The compositions, patches and landscape heteorogentity of Guangzhou urban vegetation are studied by using the principles of landscape ecology in this paper. The results showed that the area of urban vegetation was 26901 4hm 2, and the distribution of vegetation types and regional vegetation coverage were uneven. The patch areas of vegetation were large in scenery vegetation and shelter vegetation, and small in street corner vegetation and small garden vegetation. Most of patches fell in range between 100 and 10000 m 2. Only 1.13% of patches were larger than 1000000 m 2. Structure features of vegetation landscape in old urban areas were small patch, high scattering degree, high diversity, random distribution of vegetation patches and high heterogeneity. In new urban areas, the features were big patches, fine planning, medium landscape heterogeneity. Some suggestions are made according to landscape character of urban vegetation in Guangzhou.
基金supported by the Research Fund from Health Bureau of Guangzhou(201102A212006)Science and Technology Bureau of Guangzhou(2012Y2-00020)Medical Sciences Program of Guangdong(A2011507)
文摘Ecological methodology plus negative binomial regression were used to identify dengue fever (DF) epidemiological status and its relationship with meteorological variables. From 2007 to 2012, annual incidence rate of DF in Guangzhou was 0.33, 0.11, 0.15, 0.64, 0.45, and 1.34 (per 100 000) respectively, showing an increasing trend. Each 1℃ rise of temperature corresponded to an increase of 10.23% (95% CI 7.68% to 12.83%) in the monthly number of DF cases, whereas l hPa rise of atmospheric pressure corresponded to a decrease in the number of cases by 5.14% (95% CI: 7.10%-3.14%). Likewise, each one meter per second rise in wind velocity led to an increase by 43.80% or 107.53%, and one percent rise of relative humidity led to an increase by 2.04% or 2.19%.
基金Under the auspices of National Natural Science Foundation of China(No.41801150,41571146,41801144)Natural Science Foundation of Guangdong Province(No.2018A030310392)+2 种基金Guangdong Planning Project of Philosophy and Social Science(No.GD17YGL01)Science and Technology Program of Guangzhou(No.201906010033)GDAS’(Guangdong Academy of Sciences)Project of Science and Technology Development(No.2020GDASYL-20200104007)。
文摘Mobile information and communication technologies(MICTs) have fully penetrated everyday life in smart societies;this has greatly compressed time, space, and distance, and consequently, reshaped residents’ travel behaviour patterns. As a new mode of shared mobility, the sharing bicycle offers a variety of options for the daily travel of urban residents. Extant studies have mainly examined the travel characteristics and influencing factors of public bicycles with piles, while the travel patterns for sharing bicycles and their driving mechanisms have been largely ignored. Using one week’s travel data for Mobike, this study investigated the spatial and temporal distribution patterns of sharing bicycle travel behaviours in the central urban area of Guangzhou, China;furthermore, it identified the influences of built environment density factors on sharing bicycle travel behaviours based on the geographically weighted regression method. Obvious morning and evening peaks were observed in the sharing bicycle travel patterns for both weekdays and weekends. The old urban area, which had a high degree of mixed function, dense road networks, and cycling-friendly built environments, was the main travel area that attracted sharing bicycles on both weekdays and weekends. Furthermore, factors including the point of interest(POI) for the density of public transport stations, the functional mixing degree, and the density of residential POIs significantly affected residents’ travel behaviours. These findings could enrich discourse regarding shared mobility with a Chinese case characterised by rapidly developing MICTs and also provide references to local authorities for improving slow traffic environments.
文摘The concept of urban green space system planning was proposed after analyzing the background of compiling Guangzhou green space system planning and current situation of local green spaces,i.e. design landscape pattern of Guangzhou City during urban agglomeration of the Pearl River Delta,and highlight Lingnan cultures(Lingnan refers to south of the Five Ridges) and features of "Flower City"(another name of Guangzhou). Key points of planning are protecting ecological barriers in the north,improving urban garden structure in the center,using wetland reasonably in the south,to maintain integrality and continuity of the landscape pattern.
基金Under the auspices of National Natural Science Foundation of China(No.41771001)Science and Technology Planning Project Funds of Guangzhou(No.201704020136)。
文摘Understanding the spatiotemporal patterns of three-dimensional urban forms,especially building height,can have important implications for improving urban air quality and mitigating the urban heat island effect by optimizing urban planning and management policies.This study investigated building height evolution and its influencing factors over approximately half a century(1960–2017)in Guangzhou,China.The results indicated that the logarithmic declines in height,quantity,and area of urban buildings followed Zapf’s law,which restricts the three-dimensional shape of the urban form.The urban building height decreased from the center to the periphery of the city and decreased with decreasing altitude and increasing distance from main roads.These characteristics constituted the three main spatial differentiation rules of building height in the central district of Guangzhou,and all exhibited a logarithmic decrease,which gradually strengthened over time.The development of a double-layered height structure of low-rise and high-rise buildings between 1990 and 2017 was a notable manifestation of the increase in vertical urban height over time.The three factors of city center,altitude,and accessibility,which represent centrality,low relief,proximity to water,and proximity to road networks,highlighted the roles of traffic accessibility and commercial attraction in building height evolution.The importance of location macroscopically depends on the combined effect of the geographical pattern,urban planning,and market forces of cities located on a plain near hill or by a river.The principle of profit orientation restricted spatiotemporal building height patterns.
基金Sponsored by National Natural Science Foundation of China(41271060)
文摘Based on the ETM remote sensing images of Guangzhou City in 2014, the spatial distribution results o f three environmental factors including vegetation coverage(NDVI), soil index(vegetation index of bare soil) and sl ope were obtained. By using comprehensive index method, the normalized environmental factors were weighted and superimposed, and the fi nal evaluation results of ecological environment in Guangzhou City were obtained. The results showed that overall situation of natural ecological environment in Guangzhou was not optimistic, that is, the area of land with bad, moderate, good and superior environment accounted for 59.70%, 35.79%, 4.50% and around 0.01% of total area of land in Guangzhou City respectively. Ecological environment was generally poor in the central urban districts in the south of Guangzhou City, while it was relatively better in the north and northeast. Attaching importance to the constr uction of greenbelts and greenways is an effective way to improve regional environmental quality and natural ecological e nvironment level.
文摘Every 6 seconds,someone dies from cancer somewhere in the world.Every 13 seconds,a cancer patient dies in China.Cancer is currently the biggest threat to life around the world and a critical burden to China.To address this problem,it is especially important for scientists and physicians to remain abreast of cutting edge research and progress in the treatment of this disease.The 3rd Guangzhou International Symposium on Oncology
基金supported by Special Scientific Research Projects on Environmental Protection(201409029)Major Investigation Project of National Land and Resources(1212011121167)
文摘In order to find out the distribution characteristics of BTEX in groundwater, which include Benzene, Toluene, Ethylbenzene, p-Xylene, m-Xylene, and o-Xylene, 82 groups of groundwater samples and 10 surface water samples collected from Guangzhou in Guangdong during 2005 to 2008 were tested by gas chromatography and mass spectrum(GC/MS). The result showed that the BTEX concentration in groundwater does not exceed the standard. The detection rate of BTEX is 14.63% in groundwater, and the total BTEX concentration is lower than 9.5 μg/L. Of 6 kinds of BTEX, toluene had the highest detection rate(12.20%) and detection value(9.5 μg/L), which was followed by Benzene, with the detection rate of 3.65%, and detection value of 4.9 μg/L respectively; most of samples with BTEX are distributed in Huangpu district, Baiyun district, Huadu district and other industrialized areas; this spatial distribution and urban distribution have obvious consistency. With economic development, plant expansion and population growth led to a large amount of waste water discharge, and infrastructure construction is lagging behind, indicating that rapid urbanization is a major driving force of BTEX in groundwater, and through the analysis of a typical area, it is found that benzene system surface water infiltration was an important source of BTEX in groundwater of Guangzhou.
基金supported in part by the Major Research Plan of the National Natural Science Foundation of China[91543132]National Natural Science Foundation of China[81541070,30901249,81101267,and 81630025]+3 种基金Natural Science Foundation of Guangdong[10151063201000036,S2011010002526,and 2016A030313089]Guangdong Province Medical Research Foundation[A2015310]Project from Jinan university[21612426,21615426,JNUPHPM2016001,and JNUPHPM2016002]Traditional Chinese Medicine Bureau of Guangdong Province[20181071]。
文摘Objective High PM2.5 concentration is the main feature of increasing haze in developing states,but information on its microbial composition remains very limited.This study aimed to determine the composition of microbiota in PM2.5 in Guangzhou,a city located in the tropics in China.Methods In Guangzhou,from March 5th to 10th,2016,PM2.5 was collected in middle volume air samplers for 23 h daily.The 16 S rDNA V4 region of the PM2.5 sample extracted DNA was investigated using high-throughput sequence.Results Among the Guangzhou samples,Proteobacteria,Bacteroidetes,Firmicutes,Cyanobacteria,and Actinobacteria were the dominant microbiota accounting for more than 90%of the total microbiota,and Stenotrophomonas was the dominant gram-negative bacteria,accounting for 21.30%–23.57%.We examined the difference in bacterial distribution of PM2.5 between Beijing and Guangzhou at the genus level;Stenotrophomonas was found in both studies,but Escherichia was only detected in Guangzhou.Conclusion In conclusion,the diversity and specificity of microbial components in Guangzhou PM2.5 were studied,which may provide a basis for future pathogenicity research in the tropics.
文摘Proceeding from the commercial function of Guangzhou urban area, this paper expounds the principles and requirements for choosing commercial location, puts forward the bases to determine the limits of commercial centres. Thirty major commercial centres, in Guangzhou urban area are classified by means of cluster analysis. The function, size, hierarchy and interconnection of commercial centres of different groups are studied. The paper emphatically analyzes the major characteristics and formation factors of the commercial location of Guangzhou urban area. Finally, to counter some problems in existence, some suggestions are put forward in order to improve the commercial location of Guangzhou urban area.
文摘Changes in transport are likely to preduce changes in land use, and these long-term effects of transport policy may be of considerable potential importance. There is a growing movement, "The New Urbanism", which seeks to reconnect transport with land use and in particular to eslablish transitoriented development where higher-density,mixed-use areas are built around high-quality transit systems. Based on analysis on development and Pattern of urban transport inGuangzhou, this paper researches composition of urban transportation and struclure of travel pattern. The urban transport system development and change in urban form as well as change in land use are closely related. The urban transport, system required and promnoted by the high-density land-use pattern. There are many problems in the urban transportation and land-use, one of the resolving is integration of urban transport planning and land-use planning.