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Chemical characteristics of PM_(2.5) during a typical haze episode in guangzhou

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Journal of Environmental Sciences 2009年第6期21卷 774-781页

作者： TAN Jihua DUAN Jingchun HE Kebin MA Yongliang DUAN Fengkui CHEN Yuan FU Jiamo Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Chinese Research Academy of Environmental Sciences Beijing 100012 China State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The chemical characteristics（water-soluble ions and carbonaceous species） of PM2.5 in guangzhou were measured during a typical haze *** of the chemical species in PM2.5 showed significant difference between normal and haze *** 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 *** 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 ***/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 *** significantly increase in the secondary species（SOC,NO3^-,SO4^2-,and NH4^＋）,especially in NO3^-,caused the worst air quality in this ***,the result illustrated that the serious air pollution in haze episodes was strongly correlated with the meteorological *** 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 *** concentration of the secondary aerosol in haze episodes was likely due to the higher oxidation rates of sulfur and nitrogen species.

关键词： PM2.5 haze episode water-soluble inorganic ions organic carbon elemental carbon guangzhou

Evaluation of ambient air quality in guangzhou, China

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Journal of Environmental Sciences 2007年第4期19卷 432-437页

作者： ZHOU Kai YE You-hua LIU Qiang LIU Ai-jun PENG Shao-lin South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China. Graduate School of the Chinese Academy of Sciences Beijing 100039 China School of Life Sciences Sun Yat-sen University Guangzhou 510275 China Department of Biology Hainan Normal University Haikou 571158 China Climatic and Agrometeorological Center of Guangdong Province Guangzhou 510080 China

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.

关键词： air pollution index (API) total suspended particulates (TSP) atmospheric quality guangzhou

Distribution and deposition of polycyclic aromatic hydrocarbons in precipitation in guangzhou, South China

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Journal of Environmental Sciences 2009年第5期21卷 654-660页

作者： HUANG Deyin PENG Ping'an XU Yigang DENG Yunyun DENG Hongmei State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control Guangdong Institute of Eco-environment and Soil Sciences Guangzhou 510650 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Key Laboratory of lsotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

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.

关键词： polycyclic aromatic hydrocarbons distribution coefficient deposition flux precipitation guangzhou

SUSTAINABLE URBAN-RURAL RELATION IN RAPID URBANIZATION AREAS——Case of Transformation of "Urban Village" in guangzhou

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Chinese Geographical Science 2005年第3期15卷 212-218页

作者： WEI Li-hua YAN Xiao-pei College of Architecture ＆ Civil Engineering South China University of Technology Guangzhou 510640 P. R. China Center for Urban ＆ Regional Studies Sun Yat-Sen University Guangzhou 510275 P. R. China

Many studies have been made concerning the problems, characteristics, formation, transformation measures, etc. of urban village from sociology, urban planning and geography, etc., which have made insightful analysis. However, most of these studies started mainly from the standpoint of the city govemment, drumming for the land- scape-oriented urbanization, namely pulling-down the urban village and constructing the splendid residence or business buildings. The article maintains that the most important thing the city government should do is to pay much attention to the sustainable living of urban villagers, who would lose their main income source, namely, the collective dividend and the family housing rent. The single method of compensation has been proved to be harmful to the villagers＇ community, in which some young villagers relying on rent were no longer to do anything but stay at home. On the other hand, considering the floating population has become the main stream of renters in urban villages, the emergence of urban villages was inevitable and would continue to exist in a long time under the socio-economic transition in urban China and globalization. Based on the analysis above, the transformation of urban village should take more concerns on the housing demands of floating population besides compensation for local villagers. Meanwhile, it is necessary to avoid the “landscape-oriented urbanization” without the “peasant-to-citizen” transformation.

关键词： urban-rural relation rapid urbanization areas guangzhou urban village

Seasonality of insect succession on exposed rabbit carrion in guangzhou, China

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Insect Science 2009年第5期16卷 425-439页

作者： Yan-Wei Shi Xiao-Shan Liu Hai-Yang Wang Run-Jie Zhang State Key Lab for Bio-control and Institute of Entomology Sun Yat-Sen University Guangzhou China

Succession patterns for insect fauna, spanning four seasons, on rabbit carcasses were studied in guangzhou China from 2006 to 2008. A total of 49 taxa belonging to three orders and 15 families were collected and identified. Four decomposition stages were recognized： fresh, bloated, decay and dry stage. Taxa diversity was higher in bloated and decay stages than fresh and dry stages. Internal and ambient temperatures were measured. Maximum internal temperature arrived earlier in warmer seasons. The sequence of insect succession in this study follows the same general patterns： the Diptera peaked initially, and the Coleoptera peaked later. Chrysomya megacephala was the dominant species in four seasons. Its time point of different development stages on carrion could be the most important indicators for PMI （postmortem interval） estimation in guangzhou. Yearly and seasonal differences in activities of insects were compared. Alpha diversity indices were calculated. There were no significant differences in Shannon-Wiener index, evenness （J） and dominance （C） between seasons and years. From the Jaccard similarity index, the highest similarity was between winter and spring, while the lowest was between summer and winter. Some species occurring exclusively in one season may be important to characterize different seasons. A list of the insect taxa associated with above-ground rabbit carrion during the four seasons was compiled, which can be used for estimating time since death in similar bio-climate areas.

关键词： China forensic entomology guangzhou insect succession postmortem interval

Roles of urban vegetation on balance of carbon and oxygen in guangzhou, China

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Journal of Environmental Sciences 2003年第2期15卷 155-159页

作者： GUAN Dong-sheng, CHEN Yu-juan (Department of Environmental Science, Zhongshan University, guangzhou 510275, China. Department of Environmental Science Zhongshan University Guangzhou 510275 China

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.

关键词： urban vegetation carbon oxygen balance guangzhou

Excess Commuting in Transitional Urban China:A Case Study of guangzhou

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Chinese Geographical Science 2016年第5期26卷 599-608页

作者： LIU Wangbao HOU Quan School of Geography Science South China Normal UniversityGuangzhou 510631China Shenzhen Institute of Building Re-search Co. Ltd.Department of GeographyShenzhen 518033China Hong Kong Baptist University Kowloon TongHong Kong999077China

During the reform era, Chinese cities witnessed dramatic institutional transformation and spatial restructuring in general and profound change of commuting patterns in particular. Using household surveys collected in guangzhou, China, in 2001, 2005 and 2010, excess commuting measurements are estimated. Excess commuting shows an overall trend of increasing during 1990–1999, and then declining during 2000–2010. We argue that deepening marketization of the jobs and housing sectors has induced spatial separation of jobs and housing. In other words, institutional transition and urban spatial restructuring are underpinning the changes of commuting patterns in Chinese cities. Excess commuting has strong relationship with individual socio-demographic status, which is by and large due to the increasing flexibilities of jobs and housing location choices enjoyed by urban residents. The findings call for considerations on balancing jobs-housing in making public policies relevant to urban development in general, and land use and transportation in particular.

关键词： excess commuting jobs-housing balance spatial restructuring guangzhou China

Contamination of Prohibited Substances in Various Food Products in guangzhou, China

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Biomedical and Environmental Sciences 2020年第1期33卷 68-71页

作者： MHUNGU Florence HU Ke Qi ZHANG Wei Wei ZHOU Zhi Feng SHI Ming LIU Yun Gang School of Public Health Southern Medical UniversityGuangzhou 510515GuangdongChina guangzhou Centre for Disease Control and Prevention Guangzhou 510440GuangdongChina Department of Environmental and Occupational Health School of Public HealthGuangdong Medical UniversityDongguan 523808GuangdongChina

The use of antibiotics to maintain animal health has widely been practiced,for both therapeutic and prophylactic *** with the identification of serious adverse effects of some antibiotics on human and domestic animals... 详细信息

关键词： Contamination of Prohibited Substances Various Food Products guangzhou China

Changing Concepts of City and Urban Planning Practices in guangzhou(1949–2010): An Approach to Sustainable Urban Development

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Chinese Geographical Science 2014年第5期24卷 607-619页

作者： XUE Desheng HUANG Gengzhi GUAN Jingwen LIN Jiarong School of Geography and Planning Sun Yat-sen University

By focusing on guangzhou, this paper examines how different concepts of city in terms of urban-rural relationships are shaped in transforming China since 1949, and explores how they influence the way in which urban planning are practiced. In the pre-reform era, the city was defined as a productive space under the system of urban-rural segregation established for securing rapid industrialization. Urban planning was thus only concerned with the development of urban areas. In the 1980 s and 1990 s after the reform, institutional change and economic transformation mobilized the urban-rural linkages. The development of suburban areas was then considered by urban planning, but this consideration was a passive response to urban problems such as population explosion and water resources protection. Since the new millennium, the agenda for sustainable development and problems of uneven urban-rural development have called for the development of urban-rural integration. In this context, the city is conceptualized as a complex of mountain, city, river, farmland and sea, reconstructing the ideology of urban-rural division in defining urban development. Urban planning has therefore sought in an active way to develop a sustainable city embracing rural and natural elements, and to balance economic growth and environmental protection. It is argued that developing the concept of city as a complex of urban and rural elements contributes to the urban planning for sustainable urban development, while this conceptualization relies on the recognition of the integrated urban-rural relationship.

关键词： urban-rural relationship concept of city urban planning sustainable urban development guangzhou