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Metropolitan Housing Development in Urban Fringe Areas-A Case Study of Three Metropolitan Cities of South Africa: Johannesburg, Ekurhuleni and Tshwane 被引量:1
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作者 Aurobindo Ogra 《Journal of Civil Engineering and Architecture》 2024年第5期244-253,共10页
Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of So... Purpose:The metropolitan cities of Johannesburg,Ekurhuleni and Tshwane play an important role in the economy of the Gauteng province in South Africa.The region constitutes to 22.4 percent of the total population of South Africa and has a strong presence and contributes in areas of manufacturing sector,financial and business services,retail and wholesale trade,etc.The rapid urban population,increase in the informal settlements and socio-economic opportunities has resulted in considerable urban sprawl in and around the urban fringe areas of these metropolitan cities.The urban fringe areas of these metros often come under the influence of rapid urbanization process and pressures.Coupled with the economical and potential land dynamics and lack of priority of spatial development guidelines,these areas attract rapid and haphazard development from communities and developers.Research Design/Methodology:This research is based on a qualitative approach through a comprehensive literature review that included content analysis of key documents on housing sector such as IDPs(Integrated Development Plans),Municipal Annual Reports,Growth Development Strategies,and among other sectoral documents on housing sector.Some of the key priority issues considered in the housing sector included:eradication of housing backlogs,spatial restructuring of housing,provision of choice in terms of location,tenure and housing typology.Findings:The current paper discusses the approaches of metropolitan housing development processes in three metropolitan cities of South Africa from Gauteng region,namely:Johannesburg,Ekurhuleni and Tshwane.The paper discusses the existing housing sectoral scenario along with the fringe areas in three cities with focus on:formal and informal settlements,housing segregation and the backlogs,current institutional arrangements,role of public private participation,and scope for alternate mechanisms.The paper concludes in discussion on sustainable development options for housing development in urban fringe areas. 展开更多
关键词 Metropolitan housing development urban fringe areas housing backlog informal settlements urban poor land dynamics housing infrastructure PPP(public private partnership)
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Mapping ecosystem services in urban and peri-urban areas.A systematic review
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作者 Paulo Pereira Miguel Inácio +3 位作者 Luis Pinto Marius Kalinauskas Katarzyna Bogdzevic Wenwu Zhao 《Geography and Sustainability》 CSCD 2024年第3期491-509,共19页
Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply ... Urban and peri-urban ecosystems are subjected to an intense impact.The demand for ecosystem services(ES)is higher in these areas.Nevertheless,despite the anthropogenic pressures,urban and peri-urban ecosystems supply important ES.Mapping is a crucial exercise to understand ES dynamics in these environments better.This work aims to systematically review mapping ES in urban and peri-urban areas studies,following the Preferred Reporting Items for Systematic Reviews and Meta-alpha Methods.A total of 207 studies were selected.The results show increased work between 2011 and 2023,mainly conducted in Europe and China.Most work were developed in urban areas and did not follow an established ES classification.Most studies focused on the ES supply dimension,the regulation and maintenance section.Regarding provisioning ES,most studies focused on Cultivating terrestrial plants for nutrition,regulating and maintainin g Atmospheric composition and conditions,and for cultural ES on Physical and experiential interactions with the natural environment.Quantitative methods were mostly applied following Indicator-based(secondary data:biophysical,socio-economic)models.Very few work validated the outputs.Several studies forecasted ES,primarily based on land use changes using CA-Markov approaches.This study provides an overview of the most mapped urban and peri-urban ES globally,the areas where more studies need to be conducted,and the methods developed. 展开更多
关键词 Systematic review urban and peri-urban areas Ecosystem services MAPPING METHODS
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Exploring well-being disparities between urban and rural areas:A case study in the Stavropol Territory,Russia
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作者 Anastasia CHAPLITSKAYA Wim HEIJMAN Johan van OPHEM 《Regional Sustainability》 2024年第1期80-92,共13页
Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially importa... Rural areas are crucial for a country’s sustainable economy.New strategies are needed to develop rural areas to improve the well-being of rural population and generate new job opportunities.This is especially important in countries where agricultural production accounts for a significant share of the gross product,such as Russia.In this study,we identified the key indicators of satisfaction and differences between rural and urban citizens based on their social,economic,and environmental backgrounds,and determined whether there are well-being disparities between rural and urban areas in the Stavropol Territory,Russia.We collected primary data through a survey based on the European Social Survey framework to investigate the potential differences between rural and urban areas.By computing the regional well-being index using principal component analysis,we found that there was no statistically significant difference in well-being between rural and urban areas.Results of key indicators showed that rural residents felt psychologically more comfortable and safer,assessed their family relationships better,and adhered more to traditions and customs.However,urban residents showed better economic and social conditions(e.g.,infrastructures,medical care,education,and Internet access).The results of this study imply that we can better understand the local needs,advantages,and unique qualities,thereby gaining insight into the effectiveness of government programs.Policy-makers and local authorities can consider targeted interventions based on the findings of this study and strive to enhance the well-being of both urban and rural residents. 展开更多
关键词 WELL-BEING Sustainable development Rural areas urban areas Principal component analysis(PCA) RUSSIA
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Global mapping of urban built-up areas of year 2014 by combining MODIS multispectral data with VIIRS nighttime light data 被引量:5
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作者 Ram C.Sharma Ryutaro Tateishi +2 位作者 Keitarou Hara Saeid Gharechelou Kotaro Iizuka 《International Journal of Digital Earth》 SCIE EI CSCD 2016年第10期1004-1020,共17页
An improved methodology for the extraction and mapping of urban built-up areas at a global scale is presented in this study.The Moderate Resolution Imaging Spectroradiometer(MODIS)-based multispectral data were combin... An improved methodology for the extraction and mapping of urban built-up areas at a global scale is presented in this study.The Moderate Resolution Imaging Spectroradiometer(MODIS)-based multispectral data were combined with the Visible Infrared Imager Radiometer Suite(VIIRS)-based nighttime light(NTL)data for robust extraction and mapping of urban built-up areas.The MODIS-based newly proposed Urban Built-up Index(UBI)was combined with NTL data,and the resulting Enhanced UBI(EUBI)was used as a single master image for global extraction of urban built-up areas.Due to higher variation of the EUBI with respect to geographical regions,a region-specific threshold approach was used to extract urban built-up areas.This research provided 500-m-resolution global urban built-up map of year 2014.The resulted map was compared with three existing moderate-resolution global maps and one high-resolution map in the United States.The comparative analysis demonstrated finer details of the urban built-up cover estimated by the resultant map. 展开更多
关键词 urban built-up areas VIIRS MODIS nighttime light urban built-up Index global mapping
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Multi-source Data-driven Identification of Urban Functional Areas:A Case of Shenyang,China 被引量:3
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作者 XUE Bing XIAO Xiao +2 位作者 LI Jingzhong ZHAO Bingyu FU Bo 《Chinese Geographical Science》 SCIE CSCD 2023年第1期21-35,共15页
Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of ... Urban functional area(UFA)is a core scientific issue affecting urban sustainability.The current knowledge gap is mainly reflected in the lack of multi-scale quantitative interpretation methods from the perspective of human-land interaction.In this paper,based on multi-source big data include 250 m×250 m resolution cell phone data,1.81×105 Points of Interest(POI)data and administrative boundary data,we built a UFA identification method and demonstrated empirically in Shenyang City,China.We argue that the method we built can effectively identify multi-scale multi-type UFAs based on human activity and further reveal the spatial correlation between urban facilities and human activity.The empirical study suggests that the employment functional zones in Shenyang City are more concentrated in central cities than other single functional zones.There are more mix functional areas in the central city areas,while the planned industrial new cities need to develop comprehensive functions in Shenyang.UFAs have scale effects and human-land interaction patterns.We suggest that city decision makers should apply multi-sources big data to measure urban functional service in a more refined manner from a supply-demand perspective. 展开更多
关键词 human-land relationship multi-source big data urban functional area identification method Shenyang City
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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City China
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Rainwater harvesting systems: An urban flood risk mitigation measure in arid areas 被引量:1
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作者 Rouya Hdeib Marwan Aouad 《Water Science and Engineering》 EI CAS CSCD 2023年第3期219-225,共7页
Rainwater harvesting (RWH) systems have been developed to compensate for shortage in the water supply worldwide. Such systems are not very common in arid areas, particularly in the Gulf Region, due to the scarcity of ... Rainwater harvesting (RWH) systems have been developed to compensate for shortage in the water supply worldwide. Such systems are not very common in arid areas, particularly in the Gulf Region, due to the scarcity of rainfall and their reduced efficiency in covering water demand and reducing water consumption rates. In spite of this, RWH systems have the potential to reduce urban flood risks, particularly in densely populated areas. This study aimed to assess the potential use of RWH systems as urban flood mitigation measures in arid areas. Their utility in the retention of stormwater runoff and the reduction of water depth and extent were evaluated. The study was conducted in a residential area in Bahrain that experienced waterlogging after heavy rainfall events. The water demand patterns of housing units were analyzed, and the daily water balance for RWH tanks was evaluated. The effect of the implementation of RWH systems on the flood volume was evaluated with a two-dimensional hydrodynamic model. Flood simulations were conducted in several rainfall scenarios with different probabilities of occurrence. The results showed significant reductions in the flood depth and flood extent, but these effects were highly dependent on the rainfall intensity of the event. RWH systems are effective flood mitigation measures, particularly in urban arid regions short of proper stormwater control infrastructure, and they enhance the resilience of the built environment to urban floods. 展开更多
关键词 Rainwater harvesting urban floods Flood map Hydrodynamic model Built environment Arid areas
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Monitoring Study of Long-Term Land Subsidence during Subway Operation in High-Density Urban Areas Based on DInSAR-GPS-GIS Technology and Numerical Simulation
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作者 Yu Song Xuejun Chen +4 位作者 Baoping Zou Jundong Mu Rusheng Hu Siqi Cheng Shengli Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1021-1039,共19页
During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil d... During subway operation,various factors will cause long-term land subsidence,such as the vibration subsidence of foundation soil caused by train vibration load,incomplete consolidation deformation of foundation soil during tunnel construction,dense buildings and structures in the vicinity of the tunnel,and changes in water level in the stratum where the tunnel is located.The monitoring of long-term land subsidence during subway operation in high-density urban areas differs from that in low-density urban construction areas.The former is the gathering point of the entire urban population.There are many complex buildings around the project,busy road traffic,high pedestrian flow,and less vegetation cover.Several existing items requiremonitoring.However,monitoring distance is long,and providing early warning is difficult.This study uses the 2.8 km operation line between Wulin Square station and Ding’an Road station of Hangzhou Subway Line 1 as an example to propose the integrated method of DInSAR-GPS-GIS technology and the key algorithm for long-term land subsidence deformation.Then,it selects multiscene image data to analyze long-termland subsidence of high-density urban areas during subway operation.Results show that long-term land subsidence caused by the operation of Wulin Square station to Ding’an Road station of Hangzhou Subway Line 1 is small,with maximumsubsidence of 30.64 mm,and minimumsubsidence of 11.45 mm,and average subsidence ranging from 19.27 to 21.33 mm.And FLAC3D software was used to verify the monitoring situation,using the geological conditions of the soil in the study area and the tunnel profile to simulate the settlement under vehicle load,and the simulation results tended to be consistent with the monitoring situation. 展开更多
关键词 Long-term land subsidence subway operation DInSAR-GPS-GIS technology high-density urban areas urban subway numerical simulation
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Fundamental Ideas and Basic Concepts of HSR Route Selection in Complicated Urban Areas
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作者 WANG Huihuang ZHANG Yiran(Translated) 《Chinese Railways》 2023年第2期53-60,共8页
Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Pr... Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Project,research on HSR route selection in complicated urban areas has been conducted.An optimal route selection plan is determined after studying the local geological and environmental conditions and the complexity of tunnel construction.The research concludes that there are four major concerns in HSR route selection:the match between the new route and the urban planning,the potential economic return for the massive investment,the likely impacts of land expropriation on social stability,and the best synthesis of multiple controlling factors to meet the HSR standard.Moreover,six principles should be followed in railway route selection in complicated urban areas:the new route should be in alignment with the railway deployment;the route should align with the existing passage as much as possible;extensive analysis and in-depth demonstrations should be done to find the most appropriate combination of open and hidden excavation in tunnel construction;geological conditions and tunnel construction complexities are among the priorities;environmental sensitive sites and environmental vibration noise should be avoided as much as possible;special attention should be paid to the relocation of the power supply,television and communication facilities and the rearrangement of tubes and wires. 展开更多
关键词 high speed railway(HSR) complicated urban areas route selection railway network layout
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Underground space use of urban built-up areas in the central city of Nanjing:Insight based on a dynamic population distribution
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作者 Yulu Chen Zhilong Chen +3 位作者 Dongjun Guo Ziwei Zhao Tong Lin Chenhao Zhang 《Underground Space》 SCIE EI 2022年第5期748-766,共19页
With the expansion of cities and the emergence of various urban problems,urban underground space has been developed as a solution.In China’s urban transition context,there is a need for the development of underground... With the expansion of cities and the emergence of various urban problems,urban underground space has been developed as a solution.In China’s urban transition context,there is a need for the development of underground space in urban built-up areas.In this casestudy of the central city of Nanjing,we used spatial analysis and statistical methods to characterize the underground space use of urban built-up areas from a dynamic spatiotemporal perspective.We first analyzed the relationship between the population distribution and the underground space use of the central city of Nanjing based on a Baidu heat map,which can reflect the real-time population distribution,and then,we explored the spatiotemporal characteristics and spatial structure of the underground space use in urban built-up areas.The analysis results provide a reference for planning to improve and optimize the layout of underground space in the central city of Nanjing and,more generally,for the stock-type planning of underground space in urban built-up areas. 展开更多
关键词 Underground space use Dynamic population distribution urban built-up area Spatiotemporal characteristics
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The Study on Protection and Construction Mode of Urban Ecologically Sensitive Areas
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作者 尹玉洁 王璟 +3 位作者 曹星渠 刘珊 饶飞 张东伟 《Journal of Landscape Research》 2011年第9期77-78,85,共3页
The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological p... The paper had analyzed the necessity and feasibility for the protection and utilization of urban ecologically sensitive areas, proposed planning urban ecologically sensitive areas reasonably and combining ecological protection with development construction. Guiding the healthy and ordered development of urban spaces was the key part and important approach to realize ecological cities. The guiding thought for development construction of ecological cities had been discussed, which was conducting laddered development according to the location and coverage of urban ecologically sensitive areas and protection grades of these sensitive areas. Then, it had proposed four kinds of protection and construction modes, which were tourism leisure green lands, relevant expositions, industrial areas and new city groups, and which had been analyzed by combining with successful cases, so as to provide feasible win-win development strategies of ecology and economy for the planning of urban ecologically sensitive areas in the future. 展开更多
关键词 urban ecologically SENSITIVE areas ECOLOGICAL PROTECTION REASONABLE PLANNING Laddered development Construction mode
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Study on Conceptual Planning of Group Landscapes in Urban Core Areas—A Case Study of Conceptual Landscape Planning of the Core Area in Shuangsong Group,Wanzhou District of Chongqing City,China
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作者 廖春艳 沈一 《Journal of Landscape Research》 2012年第2期9-11,17,共4页
The planning site was divided into a spatial structure of"one center,one corridor,two axes,two belts and three communities"and traffic system designed to a 3-grade road system of"artery,secondary artery... The planning site was divided into a spatial structure of"one center,one corridor,two axes,two belts and three communities"and traffic system designed to a 3-grade road system of"artery,secondary artery and by-pass".Meanwhile,a 3-ring structure of the planning site was constructed:diffusion waterfront landscape belt,waterfront pathway and core eco-green island.Finally,the planning concepts for major ecological constructions were given.This study tried to explore the group eco-landscape pattern in urban core areas so as to provide a strategic instruction for the regional sustainable development. 展开更多
关键词 urban core areas Ecological landscapes Shuangsong GROUP in Wanzhou DISTRICT of CHONGQING City CONCEPTUAL landscape planning
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Urban Expansion in Major Grain Producing Area from 1978 to 2017:A Case Study of Zhengzhou Metropolitan Area,China 被引量:1
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作者 YANG Yongju ZHANG Hebing +2 位作者 QIAO Xuning LIU Liang ZHENG Jinchan 《Chinese Geographical Science》 SCIE CSCD 2023年第1期1-20,共20页
The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However,little attention has been paid to the growth process of the emerging metropolitan are... The spatial form of urbanization in China has developed from single-core city expansion to a multi-center metropolitan area.However,little attention has been paid to the growth process of the emerging metropolitan area situated in major grain producing locations in the central China.Taking the Zhengzhou metropolitan area(ZZMA)as a case study,we developed an inverse S-shape model to characterize the spatial distribution of urban land density,and constructed an urban expansion core index,urban expansion intensity index,and urban compactness index to quantify the spatial structure change that has taken place from 1978 to 2017 during the process of urban expansion.Moreover,cropland contribution rate(CR)was constructed to evaluate the impacts of urban expansion on croplands.We uncovered four key findings.First,over the past 40 yr,the ZZMA has experienced dramatic expansion,and the central city of Zhengzhou expanded faster than other cities.The gravity centers of urban expansion of surrounding cities were moving toward to Zhengzhou City.Second,the urban land density decreased with the distance from the city center to the outskirts.As the only large city,Zhengzhou has experienced the fastest and most compact centralized urban expansion,especially after 2000,while other medium-and small-sized cities have experienced low-intensity decentralized expansion.Third,the urban core has been gradually expanding outward.From 1978 to 2017,the hot-zone of urban growth has moved progressively with the acceleration of urbanization.All cities except Jiaozuo had a single peak in different periods.Forth,the cities in national core grain-producing areas has higher cropland contribution rates and lower urban expansion areas,which was closely related to cropland protection.Further analysis showed that large city was relatively better positioned than smaller cities in the efficiency of their urban infrastructure and the effectiveness of wealth creation efficiency in the urbanized area could be tested in all cities,and the policy factor seemed to play an important role in the urban expansion process. 展开更多
关键词 urban expansion major grain producing area inverse S-shape cropland contribution rate(CR) policy factor Zhengzhou metropolitan area(ZZMA)
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Assessment of Human Impacts on Vegetation in Built-up Areas in China Based on AVHRR,MODIS and DMSP_OLS Nighttime Light Data,1992–2010 被引量:5
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作者 LIU Qinping YANG Yongchun +2 位作者 TIAN Hongzhen ZHANG Bo GU Lei 《Chinese Geographical Science》 SCIE CSCD 2014年第2期231-244,共14页
Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment espec... Since the reform and opening-up program started in 1978,the level of urbanization has increased rapidly in China.Rapid urban expansion and restructuring have had significant impacts on the ecological environment especially within built-up areas.In this study,ArcGIS 10,ENVI 4.5,and Visual FoxPro 6.0 were used to analyze the human impacts on vegetation in the built-up areas of 656Chinese cities from 1992 to 2010.Firstly,an existing algorithm was refined to extract the boundaries of the built-up areas based on the Defense Meteorological Satellite Program Operational Linescan System(DMSP_OLS)nighttime light data.This improved algorithm has the advantages of high accuracy and speed.Secondly,a mathematical model(Human impacts(HI))was constructed to measure the impacts of human factors on vegetation during rapid urbanization based on Advanced Very High Resolution Radiometer(AVHRR)Normalized Difference Vegetation Index(NDVI)and Moderate Resolution Imaging Spectroradiometer(MODIS)NDVI.HI values greater than zero indicate relatively beneficial effects while values less than zero indicate proportionally adverse effects.The results were analyzed from four aspects:the size of cities(metropolises,large cities,medium-sized cities,and small cities),large regions(the eastern,central,western,and northeastern China),administrative divisions of China(provinces,autonomous regions,and municipalities)and vegetation zones(humid and semi-humid forest zone,semi-arid steppe zone,and arid desert zone).Finally,we discussed how human factors impacted on vegetation changes in the built-up areas.We found that urban planning policies and developmental stages impacted on vegetation changes in the built-up areas.The negative human impacts followed an inverted′U′shape,first rising and then falling with increase of urban scales.China′s national policies,social and economic development affected vegetation changes in the built-up areas.The findings can provide a scientific basis for municipal planning departments,a decision-making reference for government,and scientific guidance for sustainable development in China. 展开更多
关键词 vegetation change human impact urbanization built-up areas nighttime light data Normalized Difference Vegetation Index(NDVI)
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Characterization of Air Pollution in Urban Areas of Yangtze River Delta,China 被引量:7
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作者 CHEN Tan DENG Shulin +3 位作者 GAO Yu QU Lean LI Manchun CHEN Dong 《Chinese Geographical Science》 SCIE CSCD 2017年第5期836-846,共11页
The hallmark of development in the Yangtze River Delta(YRD) of East China has been sprawling urbanization. However, air pollution is a significant problem in these urban areas. In this paper, we investigated and analy... The hallmark of development in the Yangtze River Delta(YRD) of East China has been sprawling urbanization. However, air pollution is a significant problem in these urban areas. In this paper, we investigated and analyzed the air pollution index(API) in four cities(Shanghai, Nanjing, Hangzhou and Ningbo) in the YRD from 2001 to 2012. We attempted to empirically examine the relationship between meteorological factors and air quality in the urban areas of the YRD. According to the monitoring data, the API in Shanghai, Nanjing, Hangzhou slightly declined and that in Ningbo increased over the study period. We analyzed the inter-annual, seasonal, and monthly variations of API, from which we found that the air quality had different temporal changes in the four cities. It was indicated that air quality was poor in winter and spring and best in summer. Furthermore, different weather conditions affected air quality level. The wind direction was considered as an important and influential factor to air pollution, which has an impact on the accumulating or cleaning processes of pollutants. The air quality was influenced by the different wind directions that varied with seasons and cities. 展开更多
关键词 air pollution index (API) urban area meteorological factor environmental decision Yangtze River Delta China
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Effects of vegetation strata and human disturbance on bird diversity in green areas in a city in southern Chile 被引量:2
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作者 Andrés Munoz-Pedreros Marilyn González-Urrutia +1 位作者 Francisco Encina-Montoya Heraldo V.Norambuena 《Avian Research》 CSCD 2018年第4期329-343,共15页
Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green are... Background: Urbanisation is a dominant geographical trend and an important component of global change, with unprecedented implications for socio?economic, cultural and environmental characteristics. However, green areas, including original fragments, can help to conserve native diversity, improving the functioning of these artificial systems in the long term. Urban areas can still provide habitats usable by wild birds, however the structural charac?teristics of the habitat formed by different types of green area differ, and therefore dissimilar bird diversities are to be expected. The object of this study was to characterise the α and β diversities of birds in different green areas and to analyse how diversity relates to ten variables that characterise the habitat.Methods: We studied the green areas in the city of Temuco, southern Chile(Park, Square and Median strips of main streets), evaluating the variables:(a) surface area,(b) vegetation,(c) estimated human impact as the proportions of vegetation and bare soil by area, and the vehicle traffic. The bird assemblage structures were characterised by α(intra?environment) diversity and β diversity(between environments) and the statistical analysis identified the environmen?tal variables related with the presence and abundance of birds. A statistical model was constructed to describe the contribution of the variables to bird diversity.Results: We found significant differences between the diversity of bird species in the three types of green area. The β showed medium to high similarity between the different study units. There was a negative correlation with bare soil areas; the correlations with vehicle flow, plant structure and tree and shrub cover were not significant, meaning that these variables did not explain the variation in the richness of bird species between the green areas. However the surface area did explain this variation presenting a positive potential relation. There was also a high correlation with the origin(native) of shrub species.Conclusions: The bird diversity varied significantly according to the type of urban green area. The environmental variables presenting significant correlations with bird diversity were: surface area, native species of shrub stratum, shrub cover, and bare soil area. The best multiple regression model showed that the three most important variables for bird diversity are the surface area of the green area, the cover of the shrub stratum and the presence of native shrub species. 展开更多
关键词 urban BIRDS urban green area VEGETATION structure BIRD COMPOSITION Chile
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Urban surface water system in coastal areas: A comparative study between Almere and Tianjin Eco-city 被引量:2
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作者 Tao Zou Zhengnan Zhou 《Open Journal of Ecology》 2013年第6期407-416,共10页
In the purpose of defining typical urban water management challenges in coastal lowlands in the context of global climate change, a comparative study was conducted between two coastal new towns respectively located in... In the purpose of defining typical urban water management challenges in coastal lowlands in the context of global climate change, a comparative study was conducted between two coastal new towns respectively located in the Netherlands and Northern China. Comparative method is applied to define main functioning patterns of urban water systems in the two cases, then computer simulations were used to furthercompare drainage capacity in order to reveal the trends of urban water management. Major resulthas shown that Almere in the Netherlands generally more advanced in urban water management asmultiple functioning patterns are available.Strong dykes maintain competence for land subsidence and sea level rise. Open water system decreases local runoff and increaseswater retention level. Systematic control ofsluicesand locks which serve for shipping and waterfront landscaping are simultaneously isolating contaminants from outer water body. Tianjin Eco-city in China has shown both strengths and weaknesses. It takes large amount of reclaimed water as main landscaping water source, which adapts to local water pollution and shortage while requires highly centralized facilities. Large water body is reserved and huge scale underground drainage system built, but it is still vulnerable to heavy storms due to the lack of efficient surface water drainage system. Coastal line control does not adequately prevent from increasing storm surge risks in the future. SWMMsimulations have supported the viewpoint ofdistributed surface water with a higher efficiency for storm drainage. Meanwhile, surface water system returns more added values to urban development. The study is corresponding well with the theory of water sensitive city. As a conclusion, urban water system should always incorporate methods to achieve higher system resilience based on multiple functioning patterns. 展开更多
关键词 urban Surface WATER System urban WATER Management COASTAL areas SWMM
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Heavy Metal Contaminated Food Crops Irrigated with Wastewater in Peri Urban Areas, Zambia 被引量:8
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作者 Evaristo Mwaba Kapungwe 《Open Journal of Metal》 2013年第2期77-88,共12页
Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and... Studies on peri urban farming in Zambia have not adequately tackled the issues pertaining to heavy metal contaminated wastewater irrigation farming. The study investigated heavy metal contamination of water, soils and crops at two peri urban areas in Zambia. Two study sites were New Farm Extension in Mufulira Town in the Copperbelt Province and Chilumba Gardens in Kafue Town in Lusaka Province. The heavy metals investigated were lead, copper, cobalt, nickel and chromium. These heavy metals were found to be higher than acceptable limits in wastewater used to irrigate crops and there are potential human health risks associated with consumption of heavy metal contaminated food crops which have implications on the livelihoods of people. Samples of water, soil and crops were collected and analysed for lead (Pb), copper (Cu), chromium (Cr), cobalt (Co) and nickel (Ni) using the Atomic Absorption Spectrometer (AAS). The data on heavy metals was analysed using mean, standard error and T-test. The results indicated that the levels of heavy metals in wastewater, soil and food crops were above acceptable limits at two study sites. It can be concluded that there was heavy metal contamination of wastewater, soil and food crops at the two peri-urban areas in Zambia. The study highlighted the actual levels of heavy metal contaminant uptake in food crops consumed by the peri urban population. The information from this study can be used by the relevant authorities to develop appropriate measures for monitoring and control of heavy metal contamination in wastewater irrigation farming systems in peri urban areas inZambia. 展开更多
关键词 HEAVY Metal Contamination WASTEWATER Soils Food CROPS IRRIGATION FARMING Peri urban areas Zambia
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Solid Waste Management Challenges in Urban Areas of Ghana: A Case Study of Bawku Municipality 被引量:2
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作者 Nang Biyogue Douti Samuel Kojo Abanyie Steve Ampofo 《International Journal of Geosciences》 2017年第4期494-513,共20页
This study was conducted in the Bawku Municipality of the Upper East, Ghana, with the view to assessing the factors that impede the management of solid waste. Questionnaires were submitted to 150 randomly selected hou... This study was conducted in the Bawku Municipality of the Upper East, Ghana, with the view to assessing the factors that impede the management of solid waste. Questionnaires were submitted to 150 randomly selected households, while face-to-face semi-structured interviews were conducted with the municipal Waste Management Department and a private waste management company, Zoomlion Ghana Ltd. Data collected included components of solid waste generated, waste collection, transportation and final disposal methods, the challenges confronting waste management institutions, and respondents' knowledge and perceptions of the waste management system and their attitudes towards it. Components of wastes generated were organic waste, paper waste and plastics. Factors that adversely affected waste collection and transportation systems were the inadequate supply of waste collection containers, the existence of a weak waste transportation system and a low patronage of the door-to-door collection method. The study showed that the municipal landfill did not meet the required standard. The results also revealed the lack of public awareness on issues regarding waste and lack of a participatory approach that makes the people an active stakeholder in the waste management system. This situation accounted for indiscriminate disposals of waste by most respondents who viewed the issue of waste management as the exclusive responsibility of the local government. The study further showed that the waste management institutions were faced with financial difficulties, understaffing and poor logistics and nature of roads, and social constraints. The study therefore suggests the development of a strategic plan for efficient waste management which revolves around these findings. 展开更多
关键词 SOLID WASTE Management urban areas DEVELOPING COUNTRIES Ghana
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A Study on the Factors Influencing the Income Gap between Urban and Rural Areas Based on State-space Model 被引量:2
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作者 Xiaofang ZOU Xueqin JIANG 《Asian Agricultural Research》 2014年第9期1-6,共6页
The increasingly widening income gap between urban and rural areas is affected by many factors. Using the stepwise regression analysis,we find that urbanization level,socio-economic development,education level,financi... The increasingly widening income gap between urban and rural areas is affected by many factors. Using the stepwise regression analysis,we find that urbanization level,socio-economic development,education level,financial development scale and financial development efficiency have the greatest impact on the income gap between urban and rural areas. By cointegration test,it is found that there is a long-term equilibrium relationship between these five variables and the income gap between urban and rural areas. We build the state-space model to research the dynamic impact of these factors on the income gap between urban and rural areas. The results show that by improving the level of urbanization,we can effectively narrow the income gap between urban and rural areas,while socio-economic development,the improvement of education level,expansion of financial development scale and financial development efficiency all significantly expand the income gap between urban and rural areas. 展开更多
关键词 INCOME GAP BETWEEN urban and RURAL areas State-spa
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