Evaluation of urban sprawl and urban landscape pattern in a rapidly developing region.

PubMed

Lv, Zhi-Qiang; Dai, Fu-Qiang; Sun, Cheng

2012-10-01

Urban sprawl is a worldwide phenomenon happening particularly in rapidly developing regions. A study on the spatiotemporal characteristics of urban sprawl and urban pattern is useful for the sustainable management of land management and urban land planning. The present research explores the spatiotemporal dynamics of urban sprawl in the context of a rapid urbanization process in a booming economic region of southern China from 1979 to 2005. Three urban sprawl types are distinguished by analyzing overlaid urban area maps of two adjacent study years which originated from the interpretation of remote sensed images and vector land use maps. Landscape metrics are used to analyze the spatiotemporal pattern of urban sprawl for each study period. Study results show that urban areas have expanded dramatically, and the spatiotemporal landscape pattern configured by the three sprawl types changed obviously. The different sprawl type patterns in five study periods have transformed significantly, with their proportions altered both in terms of quantity and of location. The present research proves that urban sprawl quantification and pattern analysis can provide a clear perspective of the urbanization process during a long time period. Particularly, the present study on urban sprawl and sprawl patterns can be used by land use and urban planners.

Quantifying urban growth patterns in Hanoi using landscape expansion modes and time series spatial metrics.

PubMed

Nong, Duong H; Lepczyk, Christopher A; Miura, Tomoaki; Fox, Jefferson M

2018-01-01

Urbanization has been driven by various social, economic, and political factors around the world for centuries. Because urbanization continues unabated in many places, it is crucial to understand patterns of urbanization and their potential ecological and environmental impacts. Given this need, the objectives of our study were to quantify urban growth rates, growth modes, and resultant changes in the landscape pattern of urbanization in Hanoi, Vietnam from 1993 to 2010 and to evaluate the extent to which the process of urban growth in Hanoi conformed to the diffusion-coalescence theory. We analyzed the spatiotemporal patterns and dynamics of the built-up land in Hanoi using landscape expansion modes, spatial metrics, and a gradient approach. Urbanization was most pronounced in the periods of 2001-2006 and 2006-2010 at a distance of 10 to 35 km around the urban center. Over the 17 year period urban expansion in Hanoi was dominated by infilling and edge expansion growth modes. Our findings support the diffusion-coalescence theory of urbanization. The shift of the urban growth areas over time and the dynamic nature of the spatial metrics revealed important information about our understanding of the urban growth process and cycle. Furthermore, our findings can be used to evaluate urban planning policies and aid in urbanization issues in rapidly urbanizing countries.

Urban farming activity towards sustainable wellbeing of urban dwellers

NASA Astrophysics Data System (ADS)

Othman, N.; Mohamad, M.; Latip, R. A.; Ariffin, M. H.

2018-02-01

In Malaysia, urban farming is viewed as a catalyst towards achieving the well-being of urban dwellers and natural environment. Urban farming is a strategy for Malaysia’s food and economic security, and as one of the foci in the agriculture transformation whereby urban dwellers are encouraged to participate in this activity. Previous study proved that urban farming can help to address social problems of food security, urban poverty and high living cost, also provides leisure and recreation among urban dwellers. Thus, this study investigates the best urban farming practices suitable for urban setting, environment and culture of urban dwellers. Data collection was done via questionnaire survey to urban farmers of a selected community garden in Subang Jaya, Selangor. Meanwhile, on-site observations were carried out on gardening activities and the gardens’ physical attributes. The study sample encompasses of 131 urban farmers of 22 community gardens in Subang Jaya. It was found that most of the community gardens practiced crops planting on the ground or soil base planting and dwellers in the lower income group with monthly low household income constitutes the majority (83.2%) of the respondents. Social and health benefits are the highest motivating factors for urban farmers. This study provides unprecedented insights on urban farming practices and motivations in a Malaysian setting.

Urbanization in contemporary Arab Gulf states.

PubMed

Qutub, I Y

1983-01-01

Urbanization in the Arab Gulf states of Bahrain, Kuwait, Oman, Qatar, and the United Arab Emirates is analyzed. Topics discussed include the historical background to urbanization; current demographic trends in the region; urban characteristics and growth; socioeconomic factors influencing urbanization, with an emphasis on labor force structure; future urban strategy; and the need for urban research.

Urban Expansion Modeling Approach Based on Multi-Agent System and Cellular Automata

NASA Astrophysics Data System (ADS)

Zeng, Y. N.; Yu, M. M.; Li, S. N.

2018-04-01

Urban expansion is a land-use change process that transforms non-urban land into urban land. This process results in the loss of natural vegetation and increase in impervious surfaces. Urban expansion also alters the hydrologic cycling, atmospheric circulation, and nutrient cycling processes and generates enormous environmental and social impacts. Urban expansion monitoring and modeling are crucial to understanding urban expansion process, mechanism, and its environmental impacts, and predicting urban expansion in future scenarios. Therefore, it is important to study urban expansion monitoring and modeling approaches. We proposed to simulate urban expansion by combining CA and MAS model. The proposed urban expansion model based on MSA and CA was applied to a case study area of Changsha-Zhuzhou-Xiangtan urban agglomeration, China. The results show that this model can capture urban expansion with good adaptability. The Kappa coefficient of the simulation results is 0.75, which indicated that the combination of MAS and CA offered the better simulation result.

The urban forest and ecosystem services: impact on urban water, heat, and pollution cycles at the tree, street, and city scale

Treesearch

S. J. Livesley; E. G. McPherson; C. Calfapietra

2016-01-01

Many environmental challenges are exacerbated within the urban landscape, such as stormwater runoff and flood risk, chemical and particulate pollution of urban air, soil and water, the urban heat island, and summer heat waves. Urban trees, and the urban forest as a whole, can be managed to have an impact on the urban water, heat, carbon and pollution cycles. However,...

Parasitic diseases and urban development.

PubMed Central

Mott, K. E.; Desjeux, P.; Moncayo, A.; Ranque, P.; de Raadt, P.

1990-01-01

The distribution and epidemiology of parasitic diseases in both urban and periurban areas of endemic countries have been changing as development progresses. The following different scenarios involving Chagas disease, lymphatic filariasis, leishmaniasis and schistosomiasis are discussed: (1) infected persons entering nonendemic urban areas without vectors; (2) infected persons entering nonendemic urban areas with vectors; (3) infected persons entering endemic urban areas; (4) non-infected persons entering endemic urban areas; (5) urbanization or domestication of natural zoonotic foci; and (6) vectors entering nonendemic urban areas. Cultural and social habits from the rural areas, such as type of house construction and domestic water usage, are adopted by migrants to urban areas and increase the risk of disease transmission which adversely affects employment in urban populations. As the urban health services must deal with the rise in parasitic diseases, appropriate control strategies for the urban setting must be developed and implemented. PMID:2127380

Urban stormwater - greywater management system for sustainable urban water management at sub-watershed level

NASA Astrophysics Data System (ADS)

Singh Arora, Amarpreet

2017-11-01

Urban water management involves urban water supply (import, treatment and distribution of water), urban wastewater management (collection, treatment and disposal of urban sewage) and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water), and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment) both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

Ecological consequences of fragmentation and deforestation in an urban landscape: a case study

Treesearch

W.C. Zipperer; T.W. Foresman; S.P. Walker; C.T. Daniel

2012-01-01

Landscape change is an ongoing process even within established urban landscapes. Yet, analyses of fragmentation and deforestation have focused primarily on the conversion of non-urban to urban landscapes in rural landscapes and ignored urban landscapes. To determine the ecological effects of continued urbanization in urban landscapes, tree-covered patches were mapped...

Urban health in Johannesburg: the importance of place in understanding intra-urban inequalities in a context of migration and HIV.

PubMed

Vearey, Joanna; Palmary, Ingrid; Thomas, Liz; Nunez, Lorena; Drimie, Scott

2010-07-01

Developing country urban contexts present multiple challenges to those responsible for ensuring the good health of urban populations. These include urban growth, migration, informal settlements, intra-urban inequalities and - in some cases - high HIV prevalence. Using Johannesburg as a case study, this paper explores the complexities of the urban context by comparing the social determinants of urban health between migrant groups residing in the inner-city and a peripheral urban informal settlement. It is argued that any attempt to improve the health of urban populations in the context of migration and HIV requires understanding that 'place matters'. 2010 Elsevier Ltd. All rights reserved.

Friend or Foe? Urbanization and the Biosphere

NASA Astrophysics Data System (ADS)

Schneider, A.

2008-12-01

The environmental influence of urban areas is still often assumed to be negligible at global scales. Although local environmental conditions such as the urban heat island effect are well-documented, surprisingly little work has focused on cross-scale interactions, or the ways in which local urban processes cumulatively impact global changes. Given the rapid rates of rural-urban migration, economic development and urban spatial expansion, improved systems for measuring, monitoring and modeling the global environmental impacts of cities should receive far greater scientific attention. This presentation will summarize urban environmental issues and impacts at local, regional and global scales and introduce the fundamental concepts and tools needed to measure and respond to these problems. Newly available datasets for the distribution and intensity of urban land use will be introduced, demonstrating the importance of clearly defining 'urbanized' land for empirical studies at the global scale. The negative environmental impacts of urban development will be compared with the often over-looked "positives" of urban growth from a global environmental perspective. Progress in understanding and forecasting the global impacts of urban areas will require systematic global urban research designs that treat cities as urban systems, anthropogenic biomes and urban ecoregions. The challenges and opportunities of global environmental research on urban areas have important implications not only for current research but also for educating the next generation of earth system scientists.

Balancing urban and peri-urban exchange: water geography of rural livelihoods in Mexico.

PubMed

Díaz-Caravantes, Rolando E

2012-01-01

The peri-urban area is the region where there is a more dynamic interaction between the urban and rural. The peri-urban area supplies natural resources, such as land for urban expansion and agricultural products to feed the urban population. In arid and semi-arid lands, such as northern Mexico, these areas may also be the source of water for the city's domestic demand. In addition, scholars argue that peri-urban residents may have a more advantageous geographical position for selling their labour and agricultural products in cities and, by doing so, sustaining their livelihoods. A considerable number of studies have examined the peri-urban to urban natural resources transfer in terms of land annexation, housing construction, and infrastructure issues; however, the study of the effects of the reallocation of peri-urban water resources to serve urban needs is critical as well because the livelihoods of peri-urban residents, such as those based on agriculture and livestock, depend on water availability. In the case of Hermosillo there is a tremendous pressure on the water resources of peri-urban small farm communities or ejidos because of urban demand. Based on interviews and structured surveys with producers and water managers, this paper examines how peri-urban livelihoods have been reshaped by the reallocation of the city's natural resources in many cases caused some ejido members or ejidatarios to lose livelihoods.

The cosmopolitan contradictions of planetary urbanization.

PubMed

Millington, Gareth

2016-09-01

This paper explores the empirical, conceptual and theoretical gains that can be made using cosmopolitan social theory to think through the urban transformations that scholars have in recent years termed planetary urbanization. Recognizing the global spread of urbanization makes the need for a cosmopolitan urban sociology more pressing than ever. Here, it is suggested that critical urban sociology can be invigorated by focusing upon the disconnect that Henri Lefebvre posits between the planetarization of the urban - which he views as economically and technologically driven - and his dis-alienated notion of a global urban society. The first aim of this paper is to highlight the benefits of using 'cosmopolitan' social theory to understand Lefebvre's urban problematic (and to establish why this is also a cosmopolitan problematic); the second is to identify the core cosmopolitan contradictions of planetary urbanization, tensions that are both actually existing and reproduced in scholarly accounts. The article begins by examining the challenges presented to urban sociology by planetary urbanization, before considering how cosmopolitan sociological theory helps provide an analytical 'grip' on the deep lying social realities of contemporary urbanization, especially in relation to questions about difference, culture and history. These insights are used to identify three cosmopolitan contradictions that exist within urbanized (and urbanizing) space; tensions that provide a basis for a thoroughgoing cosmopolitan investigation of planetary urbanization. © London School of Economics and Political Science 2016.

Quantifying urban growth patterns in Hanoi using landscape expansion modes and time series spatial metrics

PubMed Central

Lepczyk, Christopher A.; Miura, Tomoaki; Fox, Jefferson M.

2018-01-01

Urbanization has been driven by various social, economic, and political factors around the world for centuries. Because urbanization continues unabated in many places, it is crucial to understand patterns of urbanization and their potential ecological and environmental impacts. Given this need, the objectives of our study were to quantify urban growth rates, growth modes, and resultant changes in the landscape pattern of urbanization in Hanoi, Vietnam from 1993 to 2010 and to evaluate the extent to which the process of urban growth in Hanoi conformed to the diffusion-coalescence theory. We analyzed the spatiotemporal patterns and dynamics of the built-up land in Hanoi using landscape expansion modes, spatial metrics, and a gradient approach. Urbanization was most pronounced in the periods of 2001–2006 and 2006–2010 at a distance of 10 to 35 km around the urban center. Over the 17 year period urban expansion in Hanoi was dominated by infilling and edge expansion growth modes. Our findings support the diffusion-coalescence theory of urbanization. The shift of the urban growth areas over time and the dynamic nature of the spatial metrics revealed important information about our understanding of the urban growth process and cycle. Furthermore, our findings can be used to evaluate urban planning policies and aid in urbanization issues in rapidly urbanizing countries. PMID:29734346

Urbanization and health in developing countries: a systematic review.

PubMed

Eckert, Sophie; Kohler, Stefan

2014-01-01

Future population growth will take place predominantly in cities of the developing world. The impact of urbanization on health is discussed controversially. We review recent research on urban-rural and intra-urban health differences in developing countries and investigate whether a health advantage was found for urban areas. We systematically searched the databases JSTOR, PubMed, ScienceDirect and SSRN for studies that compare health status in urban and rural areas. The studies had to examine selected World Health Organization health indicators. Eleven studies of the association between urbanization and the selected health indicators in developing countries met our selection criteria. Urbanization was associated with a lower risk of undernutrition but a higher risk of overweight in children. A lower total fertility rate and lower odds of giving birth were found for urban areas. The association between urbanization and life expectancy was positive but insignificant. Common risk factors for chronic diseases were more prevalent in urban areas. Urban-rural differences in mortality from communicable diseases depended on the disease studied. Several health outcomes were correlated with urbanization in developing countries. Urbanization may improve some health problems developing countries face and worsen others. Therefore, urbanization itself should not be embraced as a solution to health problems but should be accompanied by an informed and reactive health policy. Copyright © 2013 Longwoods Publishing.

Global typology of urban energy use and potentials for an urbanization mitigation wedge

PubMed Central

Creutzig, Felix; Baiocchi, Giovanni; Bierkandt, Robert; Pichler, Peter-Paul; Seto, Karen C.

2015-01-01

The aggregate potential for urban mitigation of global climate change is insufficiently understood. Our analysis, using a dataset of 274 cities representing all city sizes and regions worldwide, demonstrates that economic activity, transport costs, geographic factors, and urban form explain 37% of urban direct energy use and 88% of urban transport energy use. If current trends in urban expansion continue, urban energy use will increase more than threefold, from 240 EJ in 2005 to 730 EJ in 2050. Our model shows that urban planning and transport policies can limit the future increase in urban energy use to 540 EJ in 2050 and contribute to mitigating climate change. However, effective policies for reducing urban greenhouse gas emissions differ with city type. The results show that, for affluent and mature cities, higher gasoline prices combined with compact urban form can result in savings in both residential and transport energy use. In contrast, for developing-country cities with emerging or nascent infrastructures, compact urban form, and transport planning can encourage higher population densities and subsequently avoid lock-in of high carbon emission patterns for travel. The results underscore a significant potential urbanization wedge for reducing energy use in rapidly urbanizing Asia, Africa, and the Middle East. PMID:25583508

Urban Malaria: Understanding its Epidemiology, Ecology, and Transmission across Seven Diverse ICEMR Network Sites

PubMed Central

Wilson, Mark L.; Krogstad, Donald J.; Arinaitwe, Emmanuel; Arevalo-Herrera, Myriam; Chery, Laura; Ferreira, Marcelo U.; Ndiaye, Daouda; Mathanga, Don P.; Eapen, Alex

2015-01-01

A major public health question is whether urbanization will transform malaria from a rural to an urban disease. However, differences about definitions of urban settings, urban malaria, and whether malaria control should differ between rural and urban areas complicate both the analysis of available data and the development of intervention strategies. This report examines the approach of the International Centers of Excellence for Malaria Research (ICEMR) to urban malaria in Brazil, Colombia, India (Chennai and Goa), Malawi, Senegal, and Uganda. Its major theme is the need to determine whether cases diagnosed in urban areas were imported from surrounding rural areas or resulted from transmission within the urban area. If infections are being acquired within urban areas, malaria control measures must be targeted within those urban areas to be effective. Conversely, if malaria cases are being imported from rural areas, control measures must be directed at vectors, breeding sites, and infected humans in those rural areas. Similar interventions must be directed differently if infections were acquired within urban areas. The hypothesis underlying the ICEMR approach to urban malaria is that optimal control of urban malaria depends on accurate epidemiologic and entomologic information about transmission. PMID:26259941

Environmental Consequences of Rapid Urbanization in Zhejiang Province, East China

PubMed Central

Yang, Xuchao; Yue, Wenze; Xu, Honghui; Wu, Jingsheng; He, Yue

2014-01-01

Since reforms carried out in the late 1970s, China has experienced unprecedented rates of urban growth. Remote sensing data and surface observational data are used to investigate the urbanization process and related environmental consequences, focusing on extreme heat events and air pollution, in Zhejiang Province (ZJP, East China). Examination of satellite-measured nighttime light data indicates rapid urbanization in ZJP during the past decade, initially forming three urban clusters. With rapid urban sprawl, a significant Urban Heat Island (UHI) effect has emerged. During extreme heat events in summer, the UHI effect significantly exacerbates nocturnal heat stress in highly urbanized areas. Taking a long-term view, urbanization also causes additional hot days and hot degree days in urban areas. Urbanization also imposes a heavy burden on local and regional air quality in ZJP. Degraded visibility and an increase in haze days are observed at most meteorological stations, especially in the three urban clusters. The results show that urbanization has led to serious environmental problems in ZJP, not only on the city scale, but also on the regional scale. Maintaining a balance between the continuing process of urbanization and environmental sustainability is a major issue facing the local government. PMID:25019266

A gradient analysis on urban sprawl and urban landscape pattern between 1985 and 2000 in the Pearl River Delta, China

NASA Astrophysics Data System (ADS)

Dai, Erfu; Wu, Zhuo; Du, Xiaodian

2017-04-01

Urbanization is an irreversible trend worldwide, especially in rapidly developing China. Accelerated urbanization has resulted in rapid urban sprawl and urban landscape pattern changes. Quantifying the spatiotemporal dynamics of urban land use and landscape pattern not only can reveal the characteristics of social transfer and economic development, but also can provide insights into the driving mechanisms of land use changes. In this study, we integrated remote sensing (RS), geographic information system (GIS), landscape metrics, and gradient analysis to quantitatively compare the spatiotemporal dynamics of land use, urban sprawl, and landscape pattern for nine cities in the Pearl River Delta from 1985‒2000. For the whole study region, urbanization was obvious. The results show an increase in urban buildup land and shrinkage of cropland in the Pearl River Delta. However, the nine cities differed greatly in terms of the process and magnitude of urban sprawl for both the spatial and temporal dimensions. This was most evident for the cities of Guangzhou and Shenzhen. Gradient analysis on urban landscape changes could deepen understanding of the stages of urban development and provide a scientific foundation for future urban planning and land management strategies in China.

Environmental consequences of rapid urbanization in zhejiang province, East china.

PubMed

Yang, Xuchao; Yue, Wenze; Xu, Honghui; Wu, Jingsheng; He, Yue

2014-07-11

Since reforms carried out in the late 1970s, China has experienced unprecedented rates of urban growth. Remote sensing data and surface observational data are used to investigate the urbanization process and related environmental consequences, focusing on extreme heat events and air pollution, in Zhejiang Province (ZJP, East China). Examination of satellite-measured nighttime light data indicates rapid urbanization in ZJP during the past decade, initially forming three urban clusters. With rapid urban sprawl, a significant Urban Heat Island (UHI) effect has emerged. During extreme heat events in summer, the UHI effect significantly exacerbates nocturnal heat stress in highly urbanized areas. Taking a long-term view, urbanization also causes additional hot days and hot degree days in urban areas. Urbanization also imposes a heavy burden on local and regional air quality in ZJP. Degraded visibility and an increase in haze days are observed at most meteorological stations, especially in the three urban clusters. The results show that urbanization has led to serious environmental problems in ZJP, not only on the city scale, but also on the regional scale. Maintaining a balance between the continuing process of urbanization and environmental sustainability is a major issue facing the local government.

The co-integration analysis of relationship between urban infrastructure and urbanization - A case of Shanghai

NASA Astrophysics Data System (ADS)

Wang, Qianlu

2017-10-01

Urban infrastructure and urbanization influence each other, and quantitative analysis of the relationship between them will play a significant role in promoting the social development. The paper based on the data of infrastructure and the proportion of urban population in Shanghai from 1988 to 2013, use the econometric analysis of co-integration test, error correction model and Granger causality test method, and empirically analyze the relationship between Shanghai's infrastructure and urbanization. The results show that: 1) Shanghai Urban infrastructure has a positive effect for the development of urbanization and narrowing the population gap; 2) when the short-term fluctuations deviate from long-term equilibrium, the system will pull the non-equilibrium state back to equilibrium with an adjust intensity 0.342670. And hospital infrastructure is not only an important variable for urban development in short-term, but also a leading infrastructure in the process of urbanization in Shanghai; 3) there has Granger causality between road infrastructure and urbanization; and there is no Granger causality between water infrastructure and urbanization, hospital and school infrastructures of social infrastructure have unidirectional Granger causality with urbanization.

[Urban ecosystem services: A review].

PubMed

Mao, Qi-zheng; Huang, Gan-lin; Wu, Jian-guo

2015-04-01

Maintaining and improving ecosystem services in urban areas and human well-being are essential for sustainable development and therefore constitute an important topic in urban ecology. Here we reviewed studies on ecosystem services in urban areas. Based on the concept and classification of urban ecosystem services, we summarized characteristics of urban ecosystem services, including the human domination, high demand of ecosystem services in urban areas, spatial heterogeneity and temporal dynamics of ecosystem services supply and demand in urban areas, multi-services of urban green infrastructures, the socio-economic dimension of ecosystem services supply and ecosystem disservices in urban areas. Among different urban ecosystem services, the regulating service and cultural service are particularly indispensable to benefit human health. We pointed out that tradeoffs among different types of ecosystem services mostly occur between supportive service and cultural service, as well as regulating service and cultural service. In particular, we emphasized the relationship between landscape design (i.e. green infrastructure) and ecosystem services supply. Finally, we discussed current gaps to link urban ecosystem services studies to landscape design and management and pointed out several directions for future research in urban ecosystem services.

The Impact of Urban Growth and Climate Change on Heat Stress in an Australian City

NASA Astrophysics Data System (ADS)

Chapman, S.; Mcalpine, C. A.; Thatcher, M. J.; Salazar, A.; Watson, J. R.

2017-12-01

Over half of the world's population lives in urban areas. Most people will therefore be exposed to climate change in an urban environment. One of the climate risks facing urban residents is heat stress, which can lead to illness and death. Urban residents are at increased risk of heat stress due to the urban heat island effect. The urban heat island is a modification of the urban environment and increases temperatures on average by 2°C, though the increase can be much higher, up to 8°C when wind speeds and cloud cover are low. The urban heat island is also expected to increase in the future due to urban growth and intensification, further exacerbating urban heat stress. Climate change alters the urban heat island due to changes in weather (wind speed and cloudiness) and evapotranspiration. Future urban heat stress will therefore be affected by urban growth and climate change. The aim of this study was to examine the impact of urban growth and climate change on the urban heat island and heat stress in Brisbane, Australia. We used CCAM, the conformal cubic atmospheric model developed by the CSIRO, to examine temperatures in Brisbane using scenarios of urban growth and climate change. We downscaled the urban climate using CCAM, based on bias corrected Sea Surface Temperatures from the ACCESS1.0 projection of future climate. We used Representative Concentration Pathway (RCP) 8.5 for the periods 1990 - 2000, 2049 - 2060 and 2089 - 2090 with current land use and an urban growth scenario. The present day climatology was verified using weather station data from the Australian Bureau of Meteorology. We compared the urban heat island of the present day with the urban heat island with climate change to determine if climate change altered the heat island. We also calculated heat stress using wet-bulb globe temperature and apparent temperature for the climate change and base case scenarios. We found the urban growth scenario increased present day temperatures by 0.5°C in the inner city and by 6°C during a period of hot days. The scenarios of future temperature are ongoing and will show how heat stress will change in Brisbane when both urban growth and climate change are considered.

Influences of different land use spatial control schemes on farmland conversion and urban development.

PubMed

Zhou, Min; Tan, Shukui; Zhang, Lu

2015-01-01

Land use planning is always officially implemented as an effective tool to control urban development and protect farmland. However, its impact on land use change remains untested in China. Using a case study of Hang-Jia-Hu region, the main objective of this paper was to investigate the influence of different land use spatial control schemes on farmland conversion and urban development. Comparisons of farmland conversion and urban development patterns between the urban planning area and the non-urban planning area were characterized by using remote sensing, geographical information systems, and landscape metrics. Results indicated that farmland conversion in the non-urban planning area was more intensive than that in the urban planning area, and that farmland patterns was more fragmented in the non-urban planning area. Built-up land patterns in the non-urban planning area showed a trend of aggregation, while those in the urban planning area had a dual trend of fragmentation and aggregation. Existing built-up areas had less influence on built-up land sprawl in the non-urban planning area than that in the urban planning area. Built-up land sprawl in the form of continuous development in the urban planning area led to farmland conversion; and in the non-urban planning area, built-up land sprawl in the form of leapfrogging development resulted in farmland areal declines and fragmentation. We argued that it is a basic requirement to integrate land use plans in urban and non-urban planning areas for land use planning and management.

Mapping and Evaluating the Urbanization Process in Northeast China Using DMSP/OLS Nighttime Light Data

PubMed Central

Yi, Kunpeng; Tani, Hiroshi; Li, Qiang; Zhang, Jiquan; Guo, Meng; Bao, Yulong; Wang, Xiufeng; Li, Jing

2014-01-01

In this paper, an Urban Light Index (ULI) is constructed to facilitate analysis and quantitative evaluation of the process of urbanization and expansion rate by using DMSP/OLS Nighttime Light Data during the years from 1992 to 2010. A unit circle urbanization evaluation model is established to perform a comprehensive analysis of the urbanization process of 34 prefecture-level cities in Northeast China. Furthermore, the concept of urban light space is put forward. In this study, urban light space is divided into four types: the core urban area, the transition zone between urban and suburban areas, suburban area and fluorescent space. Proceeding from the temporal and spatial variation of the four types of light space, the pattern of morphologic change and space-time evolution of the four principal cities in Northeast China (Harbin, Changchun, Shenyang, Dalian) is analyzed and given particular attention. Through a correlation analysis between ULI and the traditional urbanization indexes (urban population, proportion of the secondary and tertiary industries in the regional GDP and the built-up area), the advantages and disadvantages as well as the feasibility of using the ULI in the study of urbanization are evaluated. The research results show that ULI has a strong correlation with urban built-up area (R2 = 0.8277). The morphologic change and history of the evolving urban light space can truly reflect the characteristics of urban sprawl. The results also indicate that DMSP/OLS Nighttime Light Data is applicable for extracting urban space information and has strong potential to urbanization research. PMID:24553086

Influences of Different Land Use Spatial Control Schemes on Farmland Conversion and Urban Development

PubMed Central

Zhou, Min; Tan, Shukui; Zhang, Lu

2015-01-01

Land use planning is always officially implemented as an effective tool to control urban development and protect farmland. However, its impact on land use change remains untested in China. Using a case study of Hang-Jia-Hu region, the main objective of this paper was to investigate the influence of different land use spatial control schemes on farmland conversion and urban development. Comparisons of farmland conversion and urban development patterns between the urban planning area and the non-urban planning area were characterized by using remote sensing, geographical information systems, and landscape metrics. Results indicated that farmland conversion in the non-urban planning area was more intensive than that in the urban planning area, and that farmland patterns was more fragmented in the non-urban planning area. Built-up land patterns in the non-urban planning area showed a trend of aggregation, while those in the urban planning area had a dual trend of fragmentation and aggregation. Existing built-up areas had less influence on built-up land sprawl in the non-urban planning area than that in the urban planning area. Built-up land sprawl in the form of continuous development in the urban planning area led to farmland conversion; and in the non-urban planning area, built-up land sprawl in the form of leapfrogging development resulted in farmland areal declines and fragmentation. We argued that it is a basic requirement to integrate land use plans in urban and non-urban planning areas for land use planning and management. PMID:25915897

Nesting and acoustic ecology, but not phylogeny, influence passerine urban tolerance.

PubMed

Cardoso, Gonçalo C

2014-03-01

Urbanization is one of the most extensive and ecologically significant changes happening to terrestrial environments, as it strongly affects the distribution of biodiversity. It is well established that native species richness is reduced in urban and suburban areas, but the species traits that predict tolerance to urbanization are yet little understood. In birds, one of the most studied groups in this respect, evidence is appearing that acoustic traits influence urban living, but it remains unknown how this compares to the effects of more obvious ecological traits that facilitate urban living. Therefore, it remains unclear whether acoustic communication is an important predictor of urban tolerance among species. Here, with a comparative study across 140 European and North American passerines, I show that high song frequency, which is less masked by the low-frequency anthropogenic noise, is associated with urban tolerance, with an effect size over half that of the most important ecological trait studied: off-ground nesting. Other nesting and foraging traits accepted to facilitate urban living did not differ for species occurring in urban environments. Thus, the contribution of acoustic traits for passerine urban tolerance approximates that of more obvious ecological traits. Nonetheless, effect sizes of the biological predictors of urban tolerance were low and the phylogenetic signal for urban tolerance was null, both of which suggest that factors other than phenotypic traits have major effects on urban tolerance. A simple possibility is exposure to urbanization, as there was a higher proportion of urban-tolerant species in Europe, which is more urbanized than North America. © 2013 John Wiley & Sons Ltd.

24 CFR 570.307 - Urban counties.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Urban counties. 570.307 Section 570.307 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND URBAN...

24 CFR 570.307 - Urban counties.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Urban counties. 570.307 Section 570.307 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND URBAN...

Driving factors of urban land growth in Guangzhou and its implications for sustainable development

NASA Astrophysics Data System (ADS)

Cui, Xuezhu; Li, Shaoying; Wang, Xuetong; Xue, Xiaolong

2018-04-01

Since 2000, China's urban land has expanded at a dramatic speed because of the country's rapid urbanization. The country has been experiencing unbalanced development between rural and urban areas, causing serious challenges such as agricultural security and land resources waste. Effectively evaluating the driving factors of urban land growth is essential for improving efficient land use management and sustainable urban development. This study established a principal component regression model based on eight indicators to identify their influences on urban land growth in Guangzhou. The results provided a grouping analysis of the driving factors, and found that economic growth, urban population, and transportation development are the driving forces of urban land growth of Guangzhou, while the tertiary industry has an opposite effect. The findings led to further suggestions and recommendations for urban sustainable development. Hence, local governments should design relevant policies for achieving the rational development of urban land use and strategic planning on urban sustainable development.

Loss of migration and urbanization in birds: a case study of the blackbird (Turdus merula).

PubMed

Møller, Anders Pape; Jokimäki, Jukka; Skorka, Piotr; Tryjanowski, Piotr

2014-07-01

Many organisms have invaded urban habitats, although the underlying factors initially promoting urbanization remain poorly understood. Partial migration may facilitate urbanization because such populations benefit from surplus food in urban environments during winter, and hence enjoy reduced fitness costs of migratory deaths. We tested this hypothesis in the European blackbird Turdus merula, which has been urbanized since the 19th century, by compiling information on timing of urbanization, migratory status, and population density for 99 cities across the continent. Timing of urbanization was spatially auto-correlated at scales up to 600 km. Analyses of timing of urbanization revealed that urbanization occurred earlier in partially migratory and resident populations than in migratory populations of blackbirds. Independently, this effect was most pronounced in the range of the distribution that currently has the highest population density, suggesting that urbanization facilitated population growth. These findings are consistent with the hypothesis that timing of urbanization is facilitated by partial migration, resulting in subsequent residency and population growth.

Adopting public values and climate change adaptation strategies in urban forest management: A review and analysis of the relevant literature.

PubMed

Ordóñez Barona, Camilo

2015-12-01

Urban trees are a dominant natural element in cities; they provide important ecosystem services to urban citizens and help urban areas adapt to climate change. Many rationales have been proposed to provide a purpose for urban forest management, some of which have been ineffective in addressing important ecological and social management themes. Among these rationales we find a values-based perspective, which sees management as a process where the desires of urban dwellers are met. Another perspective is climate change adaptation, which sees management as a process where urban forest vulnerability to climate change is reduced and resilience enhanced. Both these rationales have the advantage of complementing, enhancing, and broadening urban forest management objectives. A critical analysis of the literature on public values related to urban forests and climate change adaptation in the context of urban forests is undertaken to discuss what it means to adopt these two issues in urban forest management. The analysis suggests that by seeing urban forest management as a process by which public values are satisfied and urban-forest vulnerabilities to climate change are reduced, we can place issues such as naturalization, adaptive management, and engaging people in management at the centre of urban forest management. Focusing urban forest management on these issues may help ensure the success of programs focused on planting more trees and increasing citizen participation in urban forest management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Temporal and spatial variations in the relationship between urbanization and water quality.

PubMed

Ren, Lijun; Cui, Erqian; Sun, Haoyu

2014-12-01

With the development of economy, most of Chinese cities are at the stage of rapid urbanization in recent years, which has caused many environmental problems, especially the serious deterioration of water quality. Therefore, the research of the relationship between urbanization and water quality has important theoretical and practical significance, and it is also the main restriction factor in the urbanization advancement. In this work, we investigated the impact of urbanization on the water quality of the nearby river. We established a comprehensive environmental assessment framework by combining urbanization and water quality, and one model was designed to examine the impact of urbanization on the water quality in Jinan from 2001 to 2010 with factor component analysis. The assessment of urbanization level was accomplished using a comprehensive index system, which was based on four aspects: demographic urbanization, economic urbanization, land urbanization, and social urbanization. In addition, synthetic pollution index method was utilized to assess the water pollution of Xiaoqing River in the study area. Through the analysis of regression curves, we conclude that (1) when the urbanization level is below 25 %, the relationship is low and irregular; (2) if the urbanization level varies between 25 and 40 %, there will be an irreversible degradation of stream water quality; (3) there is a positive correlation between urbanization and pollution levels of urban river after the adjustment period; and (4) land and demographic aspects have the highest independent contribution. This study is a useful reference for policymakers in terms of economic and environmental management.

The Sustainable Expression of Ecological Concept in the Urban Landscape Environment Design

NASA Astrophysics Data System (ADS)

Dong, Junyan; Zhou, Tiejun; Xin, Lisen; Tan, Yuetong; Wang, Zhigang

2018-02-01

Urbanization is an inevitable trend of development of human society, also the inevitable outcome of economic development and scientific and technological progress, while urbanization process in promoting the development of human civilization, also no doubt, urban landscape has been a corresponding impact. Urban environment has suffered unprecedented damage, the urban population density, traffic congestion, shortage of resources, environmental pollution, ecological degradation, has become the focus of human society. In order to create an environment of ecological and harmonious, beautiful, sustainable development in the urban landscape, This paper discusses the concept of ecological design combined with the urban landscape design and sustainable development of urban landscape design.

Exploration of Urban Spatial Planning Evaluation Based on Humanland Harmony

NASA Astrophysics Data System (ADS)

Hu, X. S.; Ma, Q. R.; Liang, W. Q.; Wang, C. X.; Xiong, X. Q.; Han, X. H.

2017-09-01

This study puts forward a new concept, "population urbanization level forecast - driving factor analysis - urban spatial planning analysis" for achieving efficient and intensive development of urbanization considering human-land harmony. We analyzed big data for national economic and social development, studied the development trends of population urbanization and its influencing factors using the grey system model in Chengmai county of Hainan province, China. In turn, we calculated the population of Chengmai coming years based on the forecasting urbanization rate and the corresponding amount of urban construction land, and evaluated the urban spatial planning with GIS spatial analysis method in the study area. The result shows that the proposed concept is feasible for evaluation of urban spatial planning, and is meaningful for guiding the rational distribution of urban space, controlling the scale of development, improving the quality of urbanization and thus promoting highly-efficient and intensive use of limited land resource.

Study on temporal and spatial variations of urban land use based on land change data

NASA Astrophysics Data System (ADS)

Jiang, Ping; Liu, Yanfang; Fan, Min; Zhang, Yang

2009-10-01

With the rapid development of urbanization, demands of urban land increase in succession, hence, to analyze temporal and spatial variations of urban land use becomes more and more important. In this paper, the principle of trend surface analysis and formula of urban land sprawl index ( ULSI) are expatiated at first, and then based on land change data of Jiayu county, the author fits quadratic trend surface by choosing urban land area as dependent variable and urbanization and GDP as independent variables from 1996 to 2006, draws isoline of trend surface and residual values; and then urban land sprawl indexes of towns are calculated on the basis of urban land area of 1996 and 2006 and distribution map of ULSI is plotted. After analyzing those results, we can conclude that there is consanguineous relationship between urban land area and urbanization, economic level etc.

Organic Carbon Storage in China's Urban Areas

PubMed Central

Zhao, Shuqing; Zhu, Chao; Zhou, Decheng; Huang, Dian; Werner, Jeremy

2013-01-01

China has been experiencing rapid urbanization in parallel with its economic boom over the past three decades. To date, the organic carbon storage in China's urban areas has not been quantified. Here, using data compiled from literature review and statistical yearbooks, we estimated that total carbon storage in China's urban areas was 577±60 Tg C (1 Tg  = 1012 g) in 2006. Soil was the largest contributor to total carbon storage (56%), followed by buildings (36%), and vegetation (7%), while carbon storage in humans was relatively small (1%). The carbon density in China's urban areas was 17.1±1.8 kg C m−2, about two times the national average of all lands. The most sensitive variable in estimating urban carbon storage was urban area. Examining urban carbon storages over a wide range of spatial extents in China and in the United States, we found a strong linear relationship between total urban carbon storage and total urban area, with a specific urban carbon storage of 16 Tg C for every 1,000 km2 urban area. This value might be useful for estimating urban carbon storage at regional to global scales. Our results also showed that the fraction of carbon storage in urban green spaces was still much lower in China relative to western countries, suggesting a great potential to mitigate climate change through urban greening and green spaces management in China. PMID:23991014

The Urban Food-Water Nexus: Modeling Water Footprints of Urban Agriculture using CityCrop

NASA Astrophysics Data System (ADS)

Tooke, T. R.; Lathuilliere, M. J.; Coops, N. C.; Johnson, M. S.

2014-12-01

Urban agriculture provides a potential contribution towards more sustainable food production and mitigating some of the human impacts that accompany volatility in regional and global food supply. When considering the capacity of urban landscapes to produce food products, the impact of urban water demand required for food production in cities is often neglected. Urban agricultural studies also tend to be undertaken at broad spatial scales, overlooking the heterogeneity of urban form that exerts an extreme influence on the urban energy balance. As a result, urban planning and management practitioners require, but often do not have, spatially explicit and detailed information to support informed urban agricultural policy, especially as it relates to potential conflicts with sustainability goals targeting water-use. In this research we introduce a new model, CityCrop, a hybrid evapotranspiration-plant growth model that incorporates detailed digital representations of the urban surface and biophysical impacts of the built environment and urban trees to account for the daily variations in net surface radiation. The model enables very fine-scale (sub-meter) estimates of water footprints of potential urban agricultural production. Results of the model are demonstrated for an area in the City of Vancouver, Canada and compared to aspatial model estimates, demonstrating the unique considerations and sensitivities for current and future water footprints of urban agriculture and the implications for urban water planning and policy.

Effects of urbanization on carnivore species distribution and richness

USGS Publications Warehouse

Ordenana, Miguel A.; Crooks, Kevin R.; Boydston, Erin E.; Fisher, Robert N.; Lyren, Lisa M.; Siudyla, Shalene; Haas, Christopher D.; Harris, Sierra; Hathaway, Stacie A.; Turschak, Greta M.; Miles, A. Keith; Van Vuren, Dirk H.

2010-01-01

Urban development can have multiple effects on mammalian carnivore communities. We conducted a meta-analysis of 7,929 photographs from 217 localities in 11 camera-trap studies across coastal southern California to describe habitat use and determine the effects of urban proximity (distance to urban edge) and intensity (percentage of area urbanized) on carnivore occurrence and species richness in natural habitats close to the urban boundary. Coyotes (Canis latrans) and bobcats (Lynx rufus) were distributed widely across the region. Domestic dogs (Canis lupus familiaris), striped skunks (Mephitis mephitis), raccoons (Procyon lotor), gray foxes (Urocyon cinereoargenteus), mountain lions (Puma concolor), and Virginia opossums (Didelphis virginiana) were detected less frequently, and long-tailed weasels (Mustela frenata), American badgers (Taxidea taxus), western spotted skunks (Spilogale gracilis), and domestic cats (Felis catus) were detected rarely. Habitat use generally reflected availability for most species. Coyote and raccoon occurrence increased with both proximity to and intensity of urbanization, whereas bobcat, gray fox, and mountain lion occurrence decreased with urban proximity and intensity. Domestic dogs and Virginia opossums exhibited positive and weak negative relationships, respectively, with urban intensity but were unaffected by urban proximity. Striped skunk occurrence increased with urban proximity but decreased with urban intensity. Native species richness was negatively associated with urban intensity but not urban proximity, probably because of the stronger negative response of individual species to urban intensity.

Spatio-Temporal Analysis of Urban Heat Island and Urban Metabolism by Satellite Imagery over the Phoenix Metropolitan Area

NASA Astrophysics Data System (ADS)

Zhao, Q.; Zhan, S.; Kuai, X.; Zhan, Q.

2015-12-01

The goal of this research is to combine DMSP-OLS nighttime light data with Landsat imagery and use spatio-temporal analysis methods to evaluate the relationships between urbanization processes and temperature variation in Phoenix metropolitan area. The urbanization process is a combination of both land use change within the existing urban environment as well as urban sprawl that enlarges the urban area through the transformation of rural areas to urban structures. These transformations modify the overall urban climate environment, resulting in higher nighttime temperatures in urban areas compared to the surrounding rural environment. This is a well-known and well-studied phenomenon referred to as the urban heat island effect (UHI). What is unknown is the direct relationship between the urbanization process and the mechanisms of the UHI. To better understand this interaction, this research focuses on using nighttime light satellite imagery to delineate and detect urban extent changes and utilizing existing land use/land cover map or newly classified imagery from Landsat to analyze the internal urban land use variations. These data are combined with summer and winter land surface temperature data extracted from Landsat. We developed a time series of these combined data for Phoenix, AZ from 1992 to 2013 to analyze the relationships among land use change, land surface temperature and urban growth.

Changing and Differentiated Urban Landscape in China: Spatiotemporal Patterns and Driving Forces.

PubMed

Fang, Chuanglin; Li, Guangdong; Wang, Shaojian

2016-03-01

Urban landscape spatiotemporal change patterns and their driving mechanisms in China are poorly understood at the national level. Here we used remote sensing data, landscape metrics, and a spatial econometric model to characterize the spatiotemporal patterns of urban landscape change and investigate its driving forces in China between 1990 and 2005. The results showed that the urban landscape pattern has experienced drastic changes over the past 15 years. Total urban area has expanded approximately 1.61 times, with a 2.98% annual urban-growth rate. Compared to previous single-city studies, although urban areas are expanding rapidly, the overall fragmentation of the urban landscape is decreasing and is more irregular and complex at the national level. We also found a stair-stepping, urban-landscape changing pattern among eastern, central, and western counties. In addition, administrative level, urban size, and hierarchy have effects on the urban landscape pattern. We also found that a combination of landscape metrics can be used to supplement our understanding of the pattern of urbanization. The changes in these metrics are correlated with geographical indicators, socioeconomic factors, infrastructure variables, administrative level factors, policy factors, and historical factors. Our results indicate that the top priority should be strengthening the management of urban planning. A compact and congregate urban landscape may be a good choice of pattern for urban development in China.

Ecosystem services response to urbanization in metropolitan areas: Thresholds identification.

PubMed

Peng, Jian; Tian, Lu; Liu, Yanxu; Zhao, Mingyue; Hu, Yi'na; Wu, Jiansheng

2017-12-31

Ecosystem service is the key comprehensive indicator for measuring the ecological effects of urbanization. Although various studies have found a causal relationship between urbanization and ecosystem services degradation, the linear or non-linear characteristics are still unclear, especially identifying the impact thresholds in this relationship. This study quantified four ecosystem services (i.e. soil conservation, carbon sequestration and oxygen production, water yield, and food production) and total ecosystem services (TES), and then identified multiple advantageous area of ecosystem services in the peri-urban area of Beijing City. Using piecewise linear regression, the response of TES to urbanization (i.e., population density, GDP density, and construction land proportion) and its thresholds were detected. The results showed that, the TES was high in the north and west and low in the southeast, and there were seven multiple advantageous areas (distributed in the new urban development zone and ecological conservation zone), one single advantageous area (distributed in the ecological conservation zone), and six disadvantageous areas (mainly distributed in the urban function extended zone). TES response to population and economic urbanization each had a threshold (229personkm -2 and 107.15millionyuankm -2 , respectively), above which TES decreased rapidly with intensifying urbanization. However, there was a negative linear relationship between land urbanization and TES, which indicated that the impact of land urbanization on ecosystem services was more direct and effective than that of population and economic urbanization. It was also found that the negative impact of urbanization on TES was highest in the urban function extended zone, followed in descending order by that in the new urban development zone and ecological conservation zone. According to the detected relationships between urbanization and TES, the economic and population urbanization should be strengthened accompanied by slowing or even reducing land urbanization, so as to achieve urban ecological sustainability with less ecosystem services degradation. Copyright © 2017 Elsevier B.V. All rights reserved.

A Meta-Analysis of Global Urban Land Expansion

PubMed Central

Seto, Karen C.; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K.

2011-01-01

The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

The impact of urbanization and population density on childhood Plasmodium falciparum parasite prevalence rates in Africa.

PubMed

Kabaria, Caroline W; Gilbert, Marius; Noor, Abdisalan M; Snow, Robert W; Linard, Catherine

2017-01-26

Although malaria has been traditionally regarded as less of a problem in urban areas compared to neighbouring rural areas, the risk of malaria infection continues to exist in densely populated, urban areas of Africa. Despite the recognition that urbanization influences the epidemiology of malaria, there is little consensus on urbanization relevant for malaria parasite mapping. Previous studies examining the relationship between urbanization and malaria transmission have used products defining urbanization at global/continental scales developed in the early 2000s, that overestimate actual urban extents while the population estimates are over 15 years old and estimated at administrative unit level. This study sought to discriminate an urbanization definition that is most relevant for malaria parasite mapping using individual level malaria infection data obtained from nationally representative household-based surveys. Boosted regression tree (BRT) modelling was used to determine the effect of urbanization on malaria transmission and if this effect varied with urbanization definition. In addition, the most recent high resolution population distribution data was used to determine whether population density had significant effect on malaria parasite prevalence and if so, could population density replace urban classifications in modelling malaria transmission patterns. The risk of malaria infection was shown to decline from rural areas through peri-urban settlements to urban central areas. Population density was found to be an important predictor of malaria risk. The final boosted regression trees (BRT) model with urbanization and population density gave the best model fit (Tukey test p value <0.05) compared to the models with urbanization only. Given the challenges in uniformly classifying urban areas across different countries, population density provides a reliable metric to adjust for the patterns of malaria risk in densely populated urban areas. Future malaria risk models can, therefore, be improved by including both population density and urbanization which have both been shown to have significant impact on malaria risk in this study.

The Changing Face of the of Former Soviet Cities: Elucidated by Remote Sensing and Machine Learning Techniques

NASA Astrophysics Data System (ADS)

Poghosyan, Armen

2017-04-01

Despite remote sensing of urbanization emerged as a powerful tool to acquire critical knowledge about urban growth and its effects on global environmental change, human-environment interface as well as environmentally sustainable urban development, there is lack of studies utilizing remote sensing techniques to investigate urbanization trends in the Post-Soviet states. The unique challenges accompanying the urbanization in the Post-Soviet republics combined with the expected robust urban growth in developing countries over the next several decades highlight the critical need for a quantitative assessment of the urban dynamics in the former Soviet states as they navigate towards a free market democracy. This study uses total of 32 Level-1 precision terrain corrected (L1T) Landsat scenes with 30-m resolution as well as further auxiliary population and economic data for ten cities distributed in nine former Soviet republics to quantify the urbanization patterns in the Post-Soviet region. Land cover in each urban center of this study was classified by using Support Vector Machine (SVM) learning algorithm with overall accuracies ranging from 87 % to 97 % for 29 classification maps over three time steps during the past twenty-five years in order to estimate quantities, trends and drivers of urban growth in the study area. The results demonstrated several spatial and temporal urbanization patterns observed across the Post-Soviet states and based on urban expansion rates the cities can be divided into two groups, fast growing and slow growing urban centers. The relatively fast-growing urban centers have an average urban expansion rate of about 2.8 % per year, whereas the slow growing cities have an average urban expansion rate of about 1.0 % per year. The total area of new land converted to urban environment ranged from as low as 26 km2 to as high as 780 km2 for the ten cities over the 1990 - 2015 period, while the overall urban land increase ranged from 11.3 % to 96.6 % over the study period. Thus, after some initial developments following the breakup of the Soviet Union the growth rate in the urban core decreased gradually constrained by the availability of suitable land, while the urban expansion rates in the outer peripheral region were characterized with a robust urban growth rates across the study area. The rapid urban expansion observed in the former Soviet cities impairs environmentally sustainable characteristics such as compactness, better integrated land uses with abundant parks and greenbelts, low social polarization, as well as reliable public transit systems in some urban centers after the disintegration of the Soviet Union. The urban expansion rates considerably outpaced the urban population growth rates in all ten cities during the last quarter of a century, thus indicating that the urban growth is becoming more expansive with all cities experiencing significant decreases in overall urban population densities.

Planning Construction Research of Modern Urban Landscape

NASA Astrophysics Data System (ADS)

Xiao, Z. Q.; Chen, W.

With the development and expansion of the city's traditional urban landscape planning methods have been difficult to adapt to the requirements of modern urban development, in the new urban construction, planning what kind of urban landscape is a new research topic. The article discusses the principles of modern urban landscape planning and development, promote the adoption of new concepts and theories, building more regional characteristics, more humane, more perfect, more emphasis on urban landscape pattern natural ecological protection and construction can sustainable development of urban living environment, and promote the development and construction of the city.

Urban Form, Health, and the Law’s Limits

PubMed Central

Buzbee, William W.

2003-01-01

Urban form, the law, and health are undoubtedly linked. However, nonlegal factors such as 20th-century reliance on the automobile as well as associated governmental actions and private investment choices have greatly influenced urban form, especially urban sprawl. The American system of federalism, with its traditional allocation of land-use legal authority to local governments, and resulting fragmented legal authority over causes and effects of urban sprawl, renders difficult legal efforts to reshape urban form. Legal frameworks and the dynamics and effects of urban sprawl are largely mismatched. Still, existing legal frameworks and modest legal reforms provide means to encourage or at least allow urban forms that are more conducive to health. However, the law will not easily transform urban form and deter urban sprawl. PMID:12948950

Global assessment of urban and peri-urban agriculture: irrigated and rainfed croplands

NASA Astrophysics Data System (ADS)

Thebo, A. L.; Drechsel, P.; Lambin, E. F.

2014-11-01

The role of urban agriculture in global food security is a topic of increasing discussion. Existing research on urban and peri-urban agriculture consists largely of case studies that frequently use disparate definitions of urban and peri-urban agriculture depending on the local context and study objectives. This lack of consistency makes quantification of the extent of this practice at the global scale difficult. This study instead integrates global data on croplands and urban extents using spatial overlay analysis to estimate the global area of urban and peri-urban irrigated and rainfed croplands. The global area of urban irrigated croplands was estimated at about 24 Mha (11.0 percent of all irrigated croplands) with a cropping intensity of 1.48. The global area of urban rainfed croplands found was approximately 44 Mha (4.7 percent of all rainfed croplands) with a cropping intensity of 1.03. These values were derived from the MIRCA2000 Maximum Monthly Cropped Area Grids for irrigated and rainfed crops and therefore their sum does not necessarily represent the total urban cropland area when the maximum extent of irrigated and rainfed croplands occurs in different months. Further analysis of croplands within 20 km of urban extents show that 60 and 35 percent of, respectively, all irrigated and rainfed croplands fall within this distance range.

Park system concept for environmental sustainabilityin urban spatial development

NASA Astrophysics Data System (ADS)

Uniaty, Q.

2018-01-01

Urban Park System is an integrated concept between nature system and urban life. The problems caused by urban population activity resulted in the need to increase the balance between two systems. Establishment of urban park system is a response to the need for resilience of urban space structures. As an ideal requirement it needs to be built integration between the ecological, social, economic, aesthetic aspects of urban landscape architecture. The methodology was developed based on an approach to issues affecting the conditions due to urban issues and its relation to the development efforts of urban park system; Observation of Jakarta problem was obtained based on published studies and data, literature, characteristic and potential analyzes, local physical, from limited field observations. Both are simple methods aimed to describe the nature of a condition as well as form characteristics of problems in controlling the development of region, to examine the causes and symptoms. This method try to assess an object study compared between the conditions before and after. The benefits of urban park system development will not only improve the urban environment, but the value of urban pride, identity and control urban growth in line with efforts to improve the balance between conservation and development. Integrated urban park system will enhance the multifunctional role, connectivity, habitability, durability, identity and investment.

Spatio-Temporal Dynamics of Urbanization in China: Historical and Future

NASA Astrophysics Data System (ADS)

Zhou, Y.; Smith, S.; Zhao, K.; Imhoff, M. L.; Thomson, A. M.; Eom, J.; Yu, S.; Bond-Lamberty, B. P.

2014-12-01

One way humans affect the Earth is by clearing lands and building cities, a process intricately coupled with population growth. The transformation of terrestrial environments by urbanization has been accelerating during the past 30 years. China, for instance, has experienced urbanization at an unprecedented rate, with the urban population increasing from ~20% to 50% between 1980 and 2010. This urban expansion has resulted in a range of environmental and socioeconomic consequences, such as released carbon, reduced habitats, and threatened biodiversity. Improved information on historical and future urbanization is essential to understand these environmental effects, and to promote a sustainable urbanization in China. Supported by urban maps derived from nightlights remote sensing data and socio-economic drivers, we developed an integrated modeling framework to project future urban expansion in China by integrating a top-down macro-scale statistical model with a bottom-up urban growth model (three examples in Figure 1). With the models calibrated and validated using historical data, we explored annual urban growth at the province level and urban sprawl at the grid level (1-km) over the next two decades under a number of socio-economic scenarios. The results of this study will be of great value with practical implications for a sustainable urbanization (e.g. mitigation of urban heat island).

Quantifying different types of urban growth and the change dynamic in Guangzhou using multi-temporal remote sensing data

NASA Astrophysics Data System (ADS)

Sun, Cheng; Wu, Zhi-feng; Lv, Zhi-qiang; Yao, Na; Wei, Jian-bing

2013-04-01

There is a widespread concern about urban sprawl. It has negative impacts on natural resources, economic health, and community character. Without a universal definition of urban sprawl, its quantification and modeling is difficult. Traditionally, urban sprawl was described using qualitative terms, and landscape patterns. Quantitative methods are required to help local, regional and state land use planners to better identify, understand and address it. In this study, an integrated approach of remote sensing and GIS was used to identify three urban growth types of infilling growth, outlying growth and edge-expansion growth at the city of Guangzhou, China. Spatial metrics were used to characterize long-term trends and patterns of urban growth. Result shows that the proposed method can identify and visualize different urban growth types. Infilling growth is the dominant expansion type. Edge-expansion is concentrated at suburban areas. Outlying growth mainly occurs relatively far from the urban core. The analysis shows that initially the urban area expands mainly as outlying growth, causing increased fragmentation and dispersion of urban areas. Next, growth filled in vacant non-urban area inwards, resulting into a more compact and aggregated urban pattern. The study shows an improved understanding of urban growth, and helps to provide an effective way for urban planning.

Urban Malaria: Understanding its Epidemiology, Ecology, and Transmission Across Seven Diverse ICEMR Network Sites.

PubMed

Wilson, Mark L; Krogstad, Donald J; Arinaitwe, Emmanuel; Arevalo-Herrera, Myriam; Chery, Laura; Ferreira, Marcelo U; Ndiaye, Daouda; Mathanga, Don P; Eapen, Alex

2015-09-01

A major public health question is whether urbanization will transform malaria from a rural to an urban disease. However, differences about definitions of urban settings, urban malaria, and whether malaria control should differ between rural and urban areas complicate both the analysis of available data and the development of intervention strategies. This report examines the approach of the International Centers of Excellence for Malaria Research (ICEMR) to urban malaria in Brazil, Colombia, India (Chennai and Goa), Malawi, Senegal, and Uganda. Its major theme is the need to determine whether cases diagnosed in urban areas were imported from surrounding rural areas or resulted from transmission within the urban area. If infections are being acquired within urban areas, malaria control measures must be targeted within those urban areas to be effective. Conversely, if malaria cases are being imported from rural areas, control measures must be directed at vectors, breeding sites, and infected humans in those rural areas. Similar interventions must be directed differently if infections were acquired within urban areas. The hypothesis underlying the ICEMR approach to urban malaria is that optimal control of urban malaria depends on accurate epidemiologic and entomologic information about transmission. © The American Society of Tropical Medicine and Hygiene.

Futures of global urban expansion: uncertainties and implications for biodiversity conservation

NASA Astrophysics Data System (ADS)

Güneralp, B.; Seto, K. C.

2013-03-01

Urbanization will place significant pressures on biodiversity across the world. However, there are large uncertainties in the amount and location of future urbanization, particularly urban land expansion. Here, we present a global analysis of urban extent circa 2000 and probabilistic forecasts of urban expansion for 2030 near protected areas and in biodiversity hotspots. We estimate that the amount of urban land within 50 km of all protected area boundaries will increase from 450 000 km2 circa 2000 to 1440 000 ± 65 000 km2 in 2030. Our analysis shows that protected areas around the world will experience significant increases in urban land within 50 km of their boundaries. China will experience the largest increase in urban land near protected areas with 304 000 ± 33 000 km2 of new urban land to be developed within 50 km of protected area boundaries. The largest urban expansion in biodiversity hotspots, over 100 000 ± 25 000 km2, is forecasted to occur in South America. Uncertainties in the forecasts of the amount and location of urban land expansion reflect uncertainties in their underlying drivers including urban population and economic growth. The forecasts point to the need to reconcile urban development and biodiversity conservation strategies.

Urbanization, cities, and health: The challenges to Nigeria - A review.

PubMed

Aliyu, Alhaji A; Amadu, Lawal

2017-01-01

The Nigerian society is rapidly becoming urban as a result of a multitude of push and pull factors. This has generated urban health crises among city dwellers notably the urban poor. A systematic search of published literature in English was conducted between 1960 and 2015. Published peer review journals, abstracts, Gray literature (technical reports, government documents, reports, etc.), inaugural lectures, and internet articles were reviewed. Manual search of reference lists of selected articles were checked for further relevant studies. The review showed that the pace of urbanization is unprecedented with cities such as Lagos having annual urban growth rate of 5.8%. Urbanization in Nigeria is mainly demographically driven without commensurate socioeconomic dividends and benefits to the urban environment. This has created urban health crises of inadequate water safe supply, squalor and shanty settlements, sanitation, solid waste management, double burden of diseases and inefficient, congested, and risky transport system. In conclusion, when managed carefully, urbanization could reduce hardship and human suffering; on the other hand, it could also increase poverty and squalor. Some laws need to be amended to change the status of poor urban settlements. Urban health development requires intersectoral approach with political will and urban renewal program to make our urban societies sustainable that promote healthy living.

Urbanization, Cities, and Health: The Challenges to Nigeria – A Review

PubMed Central

Aliyu, Alhaji A.; Amadu, Lawal

2017-01-01

The Nigerian society is rapidly becoming urban as a result of a multitude of push and pull factors. This has generated urban health crises among city dwellers notably the urban poor. A systematic search of published literature in English was conducted between 1960 and 2015. Published peer review journals, abstracts, Gray literature (technical reports, government documents, reports, etc.), inaugural lectures, and internet articles were reviewed. Manual search of reference lists of selected articles were checked for further relevant studies. The review showed that the pace of urbanization is unprecedented with cities such as Lagos having annual urban growth rate of 5.8%. Urbanization in Nigeria is mainly demographically driven without commensurate socioeconomic dividends and benefits to the urban environment. This has created urban health crises of inadequate water safe supply, squalor and shanty settlements, sanitation, solid waste management, double burden of diseases and inefficient, congested, and risky transport system. In conclusion, when managed carefully, urbanization could reduce hardship and human suffering; on the other hand, it could also increase poverty and squalor. Some laws need to be amended to change the status of poor urban settlements. Urban health development requires intersectoral approach with political will and urban renewal program to make our urban societies sustainable that promote healthy living. PMID:29063897

What is Urban? A study of census and satellite-derived urban classes in the United States (1990-2010) with comparisons to India and Mexico

NASA Astrophysics Data System (ADS)

Balk, D.; Leyk, S.; Jones, B.; Clark, A.; Montgomery, M.

2017-12-01

Geographers and demographers have contributed much to understanding urban population and urban place. Yet, we nevertheless remain ill-prepared to fully understand past urban processes and our urban future, and importantly, connect that knowledge to pressing concerns such as climate and environmental change. This is largely due to well-known data limitations and inherent inconsistencies in the urban definition across countries and over time and spatial scales, and because urban models and definitions arise out of disciplinary silos. This paper provides a new framework for urban inquiry in that it combines urban definitions used by the U.S. Census Bureau from 1990-2010 with newly available satellite-based (mostly Landsat) data on built-up area from the Global Human Settlement Layer (GHSL). We identify areas of agreement and disagreement, as well as the population distribution underlying various GHSL derived built-up land thresholds. Our analysis allows for a systematic means of discerning peri-urban areas from other types of urban development, as well as examines differences in these patterns at the national and Metropolitan Statistical Area (MSA)-level. While we find overwhelming areas of agreement - about 70% of the census-designated urban population can be characterized as living on land that is at least 50% built-up - we also learn much of the significant heterogeneity in levels and patterns of growth between different MSAs. We further compare the US results with those for India and Mexico. This research unlocks the potential of such alternative measures for creating globally and temporally consistent proxies of urban land and may guide further research on consistent modeling of spatial demographic urban change, highly urgent for future work to distinguish between fine-scale levels of urban development and to forecast urban expansion.

Introduction: population migration and urbanization in developing countries.

PubMed

Kojima, R

1996-12-01

This introductory article discusses the correlation between migration and rapid urbanization and growth in the largest cities of the developing world. The topics include the characteristics of urbanization, government policies toward population migration, the change in absolute size of the rural population, and the problems of maintaining megacities. Other articles in this special issue are devoted to urbanization patterns in China, South Africa, Iran, Korea and Taiwan as newly industrialized economies (NIEs), informal sectors in the Philippines and Thailand, and low-income settlements in Bogota, Colombia, and India. It is argued that increased urbanization is produced by natural population growth, the expansion of the urban administrative area, and the in-migration from rural areas. A comparison of urbanization rates of countries by per capita gross national product (GNP) reveals that countries with per capita GNP of under US$2000 have urbanization rates of 10-60%. Rates are under 30% in Africa, the Middle East, South Asia, China, and Indonesia. Rapid urbanization appears to follow the economic growth curve. The rate of urbanization in Latin America is high enough to be comparable to urbanization in Europe and the US. Taiwan and Korea have high rates of urbanization that surpass the rate of industrialization. Thailand and Malaysia have low rates of urbanization compared to the size of their per capita GNP. Urbanization rates under 20% occur in countries without economic development. Rates between 20% and 50% occur in countries with or without industrialization. East Asian urbanization is progressing along with industrialization. Africa and the Middle East have urbanization without industrialization. In 1990 there were 20 developing countries and 5 developed countries with populations over 5 million. In 10 of 87 developing countries rural population declined in absolute size. The author identifies and discusses four patterns of urban growth.

Removing non-urban roads from the National Land Cover Database to create improved urban maps for the United States, 1992-2011

USGS Publications Warehouse

Soulard, Christopher E.; Acevedo, William; Stehman, Stephen V.

2018-01-01

Quantifying change in urban land provides important information to create empirical models examining the effects of human land use. Maps of developed land from the National Land Cover Database (NLCD) of the conterminous United States include rural roads in the developed land class and therefore overestimate the amount of urban land. To better map the urban class and understand how urban lands change over time, we removed rural roads and small patches of rural development from the NLCD developed class and created four wall-to-wall maps (1992, 2001, 2006, and 2011) of urban land. Removing rural roads from the NLCD developed class involved a multi-step filtering process, data fusion using geospatial road and developed land data, and manual editing. Reference data classified as urban or not urban from a stratified random sample was used to assess the accuracy of the 2001 and 2006 urban and NLCD maps. The newly created urban maps had higher overall accuracy (98.7 percent) than the NLCD maps (96.2 percent). More importantly, the urban maps resulted in lower commission error of the urban class (23 percent versus 57 percent for the NLCD in 2006) with the trade-off of slightly inflated omission error (20 percent for the urban map, 16 percent for NLCD in 2006). The removal of approximately 230,000 km2 of rural roads from the NLCD developed class resulted in maps that better characterize the urban footprint. These urban maps are more suited to modeling applications and policy decisions that rely on quantitative and spatially explicit information regarding urban lands.

A global analysis of the urban heat island effect based on multisensor satellite data

NASA Astrophysics Data System (ADS)

Xiao, J.; Frolking, S. E.; Milliman, T. E.; Schneider, A.; Friedl, M. A.

2017-12-01

Human population is rapidly urbanizing. In much of the world, cities are prone to hotter weather than surrounding rural areas - so-called `urban heat islands' - and this effect can have mortal consequences during heat waves. During the daytime, when the surface energy balance is driven by incoming solar radiation, the magnitude of urban warming is strongly influenced by surface albedo and the capacity to evaporate water (i.e., there is a strong relationship between vegetated land fraction and the ratio of sensible to latent heat loss or Bowen ratio). At nighttime, urban cooling is often inhibited by the thermal inertia of the built environment and anthropogenic heat exhaust from building and transportation energy use. We evaluated a suite of global remote sensing data sets representing a range of urban characteristics against MODIS-derived land-surface temperature differences between urban and surrounding rural areas. We included two new urban datasets in this analysis - MODIS-derived change in global urban extent and global urban microwave backscatter - along with several MODIS standard products and DMSP/OLS nighttime lights time series data. The global analysis spanned a range of urban characteristics that likely influence the magnitude of daytime and/or nighttime urban heat islands - urban size, population density, building density, state of development, impervious fraction, eco-climatic setting. Specifically, we developed new satellite datasets and synthesizing these with existing satellite data into a global database of urban land surface parameters, used two MODIS land surface temperature products to generate time series of daytime and nighttime urban heat island effects for 30 large cities across the globe, and empirically analyzed these data to determine specifically which remote sensing-based characterizations of global urban areas have explanatory power with regard to both daytime and nighttime urban heat islands.

Does Urban Form Affect Urban NO2? Satellite-Based Evidence for More than 1200 Cities.

PubMed

Bechle, Matthew J; Millet, Dylan B; Marshall, Julian D

2017-11-07

Modifying urban form may be a strategy to mitigate urban air pollution. For example, evidence suggests that urban form can affect motor vehicle usage, a major contributor to urban air pollution. We use satellite-based measurements of urban form and nitrogen dioxide (NO 2 ) to explore relationships between urban form and air pollution for a global data  set of 1274 cities. Three of the urban form metrics studied (contiguity, circularity, and vegetation) have a statistically significant relationship with urban NO 2 ; their combined effect could be substantial. As illustration, if findings presented here are causal, that would suggest that if Christchurch, New Zealand (a city at the 75th percentile for all three urban-form metrics, and with a network of buses, trams, and bicycle facilities) was transformed to match the urban form of Indio - Cathedral City, California, United States (a city at the 25th percentile for those same metrics, and exhibiting sprawl-like suburban development), our models suggest that Christchurch's NO 2 concentrations would be ∼60% higher than its current level. We also find that the combined effect of urban form on NO 2 is larger for small cities (β × IQR = -0.46 for cities < ∼300 000 people, versus -0.22 for all cities), an important finding given that cities less than 500 000 people contain a majority of the urban population and are where much of the future urban growth is expected to occur. This work highlights the need for future study of how changes in urban form and related land use and transportation policies impact urban air pollution, especially for small cities.

Urban food self-reliance: significance and prospects.

PubMed

Mougeot, L J

1993-10-01

This news account provides coverage of the satisfaction of urban food needs when retail costs are prohibitively high in developing countries. This account reports that 50-80% of average income is spent on food in nearly 50% of developing country's largest cities. Surveys conducted during the late 1980s confirm a range of 60-80% of income for expenditures on food. Surveys reveal that urban food costs are 10-30% higher than costs for rural dwellers. Urban household food production is a practice that has been around since the times of the Aztecs, the Incas, and Mayan cities. Reports survive of the Javanese and city dwellers along the Tigris and Euphrates producing their own food. Asian policy makers promote urban food production as critical to urban survival. Other factors influence urban food production. These factors include rapid urbanization, ineffective agricultural policies, inadequate food distribution systems, withdrawal of subsidies, reduction of wages, inflation, unemployment, lax urban regulations, civil strife, and drought. Government agencies are sometimes obstacles in outlawing the practice. Recent support for urban agriculture includes ten Asian, six African, and six Latin American countries. The number of urban farm workers is reported as 200 million worldwide. 700 million receive the benefits of urban agriculture. 25% of urban households in the US were engaged in urban food production during the 1980s. Better information, such as in comparative and longitudinal studies, is needed on urban poverty and the links between nutrition, income, employment, waste, and environmental issues. If cost-benefit analysis research finds a positive impact, then urban planners may need to incorporate city farming into conventional land use. The value of city farming needs to be assessed. Street food vending is an important source of income, particularly for women. Urban farming requires efficiency of space and knowledge of advances in technology and planning.

Observing the Vertical Dimensions of Singapore's Urban Heat Island

NASA Astrophysics Data System (ADS)

Chow, W. T. L.; Ho, D. X. Q.

2015-12-01

In numerous cities, measurements of urban warmth in most urban heat island (UHI) studies are generally constrained towards surface or near-surface (<2 m above ground) levels across horizontal variations in land use and land cover. However, there has been hitherto limited attention towards the measurement of vertical temperature profiles extending from the urban surface through to the urban boundary layer. Knowledge of these profiles, through how they vary over different local urban morphologies, and develop with respect to synoptic meteorological conditions, are important towards several aspects of UHI research; these include validating modelling urban canopy lapse rate profiles or estimating the growth of urban plumes. In this study, we utilised temperature sensors attached onto remote controlled aerial quadcopter platforms to measure urban temperature and humidity profiles in Singapore, which is a rapidly urbanizing major tropical metropolis. These profiles were measured from the surface to ~100 m above ground level, a height which includes all of the urban canopy and parts of the urban boundary layer. Initial results indicate significant variations in stability measured over different land uses (e.g. urban park, high-rise residential, commercial); these profiles are also temporally dynamic, depending on the time of day and larger-scale weather conditions.

Quantitative analysis of urban sprawl in Tripoli using Pearson's Chi-Square statistics and urban expansion intensity index

NASA Astrophysics Data System (ADS)

Al-sharif, Abubakr A. A.; Pradhan, Biswajeet; Zulhaidi Mohd Shafri, Helmi; Mansor, Shattri

2014-06-01

Urban expansion is a spatial phenomenon that reflects the increased level of importance of metropolises. The remotely sensed data and GIS have been widely used to study and analyze the process of urban expansions and their patterns. The capital of Libya (Tripoli) was selected to perform this study and to examine its urban growth patterns. Four satellite imageries of the study area in different dates (1984, 1996, 2002 and 2010) were used to conduct this research. The main goal of this work is identification and analyzes the urban sprawl of Tripoli metropolitan area. Urban expansion intensity index (UEII) and degree of freedom test were used to analyze and assess urban expansions in the area of study. The results show that Tripoli has sprawled urban expansion patterns; high urban expansion intensity index; and its urban development had high degree of freedom according to its urban expansion history during the time period (1984-2010). However, the novel proposed hypothesis used for zones division resulted in very good insight understanding of urban expansion direction and the effect of the distance from central business of district (CBD).

An analysis of urban thermal characteristics and associated land cover in Tampa Bay and Las Vegas using Landsat satellite data

USGS Publications Warehouse

Xian, George; Crane, Mike

2006-01-01

Remote sensing data from both Landsat 5 and Landsat 7 systems were utilized to assess urban area thermal characteristics in Tampa Bay watershed of west-central Florida, and the Las Vegas valley of southern Nevada. To quantitatively determine urban land use extents and development densities, sub-pixel impervious surface areas were mapped for both areas. The urban–rural boundaries and urban development densities were defined by selecting certain imperviousness threshold values and Landsat thermal bands were used to investigate urban surface thermal patterns. Analysis results suggest that urban surface thermal characteristics and patterns can be identified through qualitatively based urban land use and development density data. Results show the urban area of the Tampa Bay watershed has a daytime heating effect (heat-source), whereas the urban surface in Las Vegas has a daytime cooling effect (heat-sink). These thermal effects strongly correlated with urban development densities where higher percent imperviousness is usually associated with higher surface temperature. Using vegetation canopy coverage information, the spatial and temporal distributions of urban impervious surface and associated thermal characteristics are demonstrated to be very useful sources in quantifying urban land use, development intensity, and urban thermal patterns.

Temperature trends in desert cities: how vegetation and urbanization affect the urban heat island dynamics in hyper-arid climates

NASA Astrophysics Data System (ADS)

Marpu, P. R.; Lazzarini, M.; Molini, A.; Ghedira, H.

2013-12-01

Urban areas represent a unique micro-climatic system, mainly characterized by scarcity of vegetation and ground moisture, an albedo strictly dependent on building materials and urban forms, high heat capacity, elevated pollutants emissions, anthropogenic heat production, and a characteristic boundary layer dynamics. For obvious historical reasons, the first to be addressed in the literature were the effects of urbanization on the local microclimate of temperate regions, where most of the urban development took place in the last centuries. Here micro-climatic characteristics all contribute to the warming of urban areas, also known as 'urban heat island' effect, and are expected to crucially impact future energy and water consumption, air quality, and human health. However, rapidly increasing urbanization rates in arid and hyper-arid developing countries could soon require more attention towards studying the effects of urban development on arid climates, which remained mainly unexplored till now. In this talk we investigate the climatology of urban heat islands in seven highly urbanized desert cities based on day and night temporal trends of land surface temperature (LST) and normalized difference vegetation index (NDVI) acquired using MODIS satellite during 2000-2012. Urban and rural areas are distinguished by analyzing the high-resolution temporal variability and averaged monthly values of LST, NDVI and Surface Urban Heat Island (SUHI) for all the seven cities and adjacent sub-urban areas. Different thermal behaviors were observed at the selected sites, also including temperature mitigation and inverse urban heat island, and are here discussed together with detailed analysis of the corresponding trends.

Advanced seasonal reproductive development in a male urban bird is reflected in earlier plasma luteinizing hormone rise but not energetic status.

PubMed

Davies, Scott; Behbahaninia, Hirbod; Giraudeau, Mathieu; Meddle, Simone L; Waites, Kyle; Deviche, Pierre

2015-12-01

Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

A temperature and vegetation adjusted NTL urban index for urban area mapping and analysis

NASA Astrophysics Data System (ADS)

Zhang, Xiya; Li, Peijun

2018-01-01

Accurate and timely information regarding the extent and spatial distribution of urban areas on regional and global scales is crucially important for both scientific and policy-making communities. Stable nighttime light (NTL) data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) provides a unique proxy of human settlement and activity, which has been used in the mapping and analysis of urban areas and urbanization dynamics. However, blooming and saturation effects of DMSP/OLS NTL data are two unresolved problems in regional urban area mapping and analysis. This study proposed a new urban index termed the Temperature and Vegetation Adjusted NTL Urban Index (TVANUI). It is intended to reduce blooming and saturation effects and to enhance urban features by combining DMSP/OLS NTL data with Normalized Difference Vegetation Index (NDVI) and land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer onboard the Terra satellite. The proposed index was evaluated in two study areas by comparison with established urban indices. The results demonstrated the proposed TVANUI was effective in enhancing the variation of DMSP/OLS light in urban areas and in reducing blooming and saturation effects, showing better performance than three established urban indices. The TVANUI also significantly outperformed the established urban indices in urban area mapping using both the global-fixed threshold and the local-optimal threshold methods. Thus, the proposed TVANUI provides a useful variable for urban area mapping and analysis on regional scale, as well as for urbanization dynamics using time-series DMSP/OLS and related satellite data.

Length of urban residence and obesity among within-country rural-to-urban Andean migrants.

PubMed

Antiporta, Daniel A; Smeeth, Liam; Gilman, Robert H; Miranda, J Jaime

2016-05-01

To evaluate the association between length of residence in an urban area and obesity among Peruvian rural-to-urban migrants. Cross-sectional database analysis of the migrant group from the PERU MIGRANT Study (2007). Exposure was length of urban residence, analysed as both a continuous (10-year units) and a categorical variable. Four skinfold site measurements (biceps, triceps, subscapular and suprailiac) were used to calculate body fat percentage and obesity (body fat percentage >25% males, >33% females). We used Poisson generalized linear models to estimate adjusted prevalence ratios and 95 % confidence intervals. Multicollinearity between age and length of urban residence was assessed using conditional numbers and correlation tests. A peri-urban shantytown in the south of Lima, Peru. Rural-to-urban migrants (n 526) living in Lima. Multivariable analyses showed that for each 10-year unit increase in residence in an urban area, rural-to-urban migrants had, on average, a 12 % (95 % CI 6, 18 %) higher prevalence of obesity. This association was also present when length of urban residence was analysed in categories. Sensitivity analyses, conducted with non-migrant groups, showed no evidence of an association between 10-year age units and obesity in rural (P=0·159) or urban populations (P=0·078). High correlation and a large conditional number between age and length of urban residence were found, suggesting a strong collinearity between both variables. Longer lengths of urban residence are related to increased obesity in rural-to-urban migrant populations; therefore, interventions to prevent obesity in urban areas may benefit from targeting migrant groups.

The relationship between urban form and air pollution depends on seasonality and city size.

PubMed

Liu, Yupeng; Wu, Jianguo; Yu, Deyong; Ma, Qun

2018-06-01

Understanding how urban form is related to air pollution is important to urban planning and sustainability, but the urban form-air pollution relationship is currently muddled by inconsistent findings. In this study, we investigated how the compositional and configurational attributes of urban form were related to different air pollution measures (PM 2.5 , API, and exceedance) in 83 Chinese cities, with explicit consideration of city size and seasonality. Ten landscape metrics were selected to quantify urban form attributes, and Spearman's correlation was used to quantify the urban form-air pollution relationship. Our results show that the urban form and air pollution relationship was dominated by city size and moderated by seasonality. Specifically, urban air pollution levels increased consistently and substantially from small to medium, large, and megacities. The urban form-air pollution relationship depended greatly on seasonality and monsoons. That is, the relationship was more pronounced in spring and summer than fall and winter, as well as in cities affected by monsoons. Urban air pollution was correlated more strongly with landscape composition metrics than landscape configuration metrics which seemed to affect only PM 2.5 concentrations. Our study suggests that, to understand how air pollution levels are related to urban form, city size and seasonality must be explicitly considered (or controlled). Also, in order to mitigate urban air pollution problems, regional urban planning is needed to curb the spatial extent of built-up areas, reduce the degree of urban fragmentation, and increase urban compactness and contiguity, especially for large and megacities.

CADDIS Volume 2. Sources, Stressors and Responses: Urbanization - Hydrology

EPA Pesticide Factsheets

hydrologic (or flow) changes associated with urbanization, baseflow changes associated with urbanization, water withdrawals and interbasin transfers associated with urbanization, biotic responses to hydrologic (or flow) changes associated with urbanization

Understanding Urban Development In Canada. "Understanding Economics" Series No. 3.

ERIC Educational Resources Information Center

Plunkett, T. J.

This booklet for Canadian secondary school students examines urbanization and its relationship to other factors of the economy. Five sections analyze urbanization, the pattern of urban development, community needs, the management of urban growth, and urban governance. Part I traces the growth of the Canadian population, noting that 10% of the…

Lead in urban soils - A real or perceived concern for urban agriculture

USDA-ARS?s Scientific Manuscript database

Urban agriculture is growing in cities across the U.S. and it has the potential to provide multiple benefits including increased food security. Concerns about soil contamination in urban areas can be an impediment to urban agriculture. Lead is the most common contaminant in urban areas. A review ...

Transforming Perceptions of Urban Education: Lessons from Rowan University's Urban Teacher Academy

ERIC Educational Resources Information Center

White, Meg; Brown, Corine Meredith; Viator, Martha Graham; Byrne, Laurel L.; Ricchezza, Lorraine C.

2017-01-01

To be an effective urban educator requires teachers to understand the contextual factors of students, the school, and the community, and their cumulative effects on learning. Urban teacher academies support a better understanding of urban classrooms and challenge stereotypes of the urban context. The focus of this study was to compare…

Exploring Urban America: An Introductory Reader.

ERIC Educational Resources Information Center

Caves, Roger W.

This introductory text presents a collection of articles from urban-studies journals to introduce undergraduate students to the interdisciplinary field of urban studies. The book is divided into 9 parts as follows: Part 1: Cities and Urbanism; part 2: Urban History; part 3: Urban Policy; part 4: Economic Development; part 5: Community Services and…

Teacher Educators' Understanding of Diversity Painting a Picture through Narrative Portraits

ERIC Educational Resources Information Center

Stenhouse, Vera L.

2012-01-01

Education research literature is rife with images of pre- and in-service teachers in urban settings. Entire publications are grounded in the study of this population (see Journal of Urban Education, Education and Urban Society, The Urban Review, Perspectives on Urban Education, The National Journal of Urban Education, and Rethinking Schools). In…

Metal concentrations in urban riparian sediments along an urbanization gradient

Treesearch

Daniel J. Bain; Ian D. Yesilonis; Richard V. Pouyat

2012-01-01

Urbanization impacts fluvial systems via a combination of changes in sediment chemistry and basin hydrology. While chemical changes in urban soils have been well characterized, similar surveys of riparian sediments in urbanized areas are rare. Metal concentrations were measured in sediments collected from riparian areas across the urbanization gradient in Baltimore, MD...

Trace elements and nitrogen content in naturally growing moss Hypnum cupressiforme in urban and peri-urban forests of the Municipality of Ljubljana (Slovenia).

PubMed

Berisha, S; Skudnik, M; Vilhar, U; Sabovljević, M; Zavadlav, S; Jeran, Z

2017-02-01

We monitored trace metals and nitrogen using naturally growing moss Hypnum cupressiforme Hedw. in urban and peri-urban forests of the City Municipality of Ljubljana. The aim of this study was to explore the differences in atmospheric deposition of trace metals and nitrogen between urban and peri-urban forests. Samples were collected at a total of 44 sites in urban forests (forests within the motorway ring road) and peri-urban forests (forests outside the motorway ring road). Mosses collected in urban forests showed increased trace metal concentrations compared to samples collected from peri-urban forests. Higher values were significant for As, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Tl and V. Within the motorway ring road, the notable differences in element concentrations between the two urban forests were significant for Cr, Ni and Mo. Factor analysis showed three groups of elements, highlighting the contribution of traffic emissions, individual heating appliances and the resuspension of contaminated soils and dust as the main sources of trace elements in urban forests.

CADDIS Volume 2. Sources, Stressors and Responses: Urbanization - Overview

EPA Pesticide Factsheets

Introduction to urbanization and its effects of streams, a summary of the urban stream syndrome,an overview of the effects of urbanization on biotic integrity, a summary of catchment vs. riparian urbanization.

Spatial assessment of landscape ecological connectivity in different urban gradient.

PubMed

Park, Sohyun

2015-07-01

Urbanization has resulted in remnant natural patches within cities that often have no connectivity among themselves and to natural reserves outside the urban area. Protecting ecological connectivity in fragmented urban areas is becoming crucial in maintaining urban biodiversity and securing critical habitat levels and configurations under continual development pressures. Nevertheless, few studies have been undertaken for urban landscapes. This study aims to assess ecological connectivity for a group of species that represent the urban desert landscape in the Phoenix metropolitan area and to compare the connectivity values along the different urban gradient. A GIS-based landscape connectivity model which relies upon ecological connectivity index (ECI) was developed and applied to this region. A GIS-based concentric buffering technique was employed to delineate conceptual boundaries for urban, suburban, and rural zones. The research findings demonstrated that urban habitats and potential habitat patches would be significantly influenced by future urban development. Particularly, the largest loss of higher connectivity would likely to be anticipated in the "in-between areas" where urban, suburban, and rural zones overlap one another. The connectivity maps would be useful to provide spatial identification regarding connectivity patterns and vulnerability for urban and suburban activities in this area. This study provides planners and landscape architects with a spatial guidance to minimize ecological fragmentation, which ultimately leads to urban landscape sustainability. This study suggests that conventional planning practices which disregard the ecological processes in urban landscapes need to integrate landscape ecology into planning and design strategies.

Multiscale and Multitemporal Urban Remote Sensing

NASA Astrophysics Data System (ADS)

Mesev, V.

2012-07-01

The remote sensing of urban areas has received much attention from scientists conducting studies on measuring sprawl, congestion, pollution, poverty, and environmental encroachment. Yet much of the research is case and data-specific where results are greatly influenced by prevailing local conditions. There seems to be a lack of epistemological links between remote sensing and conventional theoretical urban geography; in other words, an oversight for the appreciation of how urban theory fuels urban change and how urban change is measured by remotely sensed data. This paper explores basic urban theories such as centrality, mobility, materiality, nature, public space, consumption, segregation and exclusion, and how they can be measured by remote sensing sources. In particular, the link between structure (tangible objects) and function (intangible or immaterial behavior) is addressed as the theory that supports the wellknow contrast between land cover and land use classification from remotely sensed data. The paper then couches these urban theories and contributions from urban remote sensing within two analytical fields. The first is the search for an "appropriate" spatial scale of analysis, which is conveniently divided between micro and macro urban remote sensing for measuring urban structure, understanding urban processes, and perhaps contributions to urban theory at a variety of scales of analysis. The second is on the existence of a temporal lag between materiality of urban objects and the planning process that approved their construction, specifically how time-dependence in urban structural-functional models produce temporal lags that alter the causal links between societal and political functional demands and structural ramifications.

The Vertical Structure of Urban Soils and Their Convergence Across Cities

NASA Astrophysics Data System (ADS)

Herrmann, D.; Schifman, L. A.; Shuster, W.; Schwarz, K.

2017-12-01

The theoretical patterns for vertical soil structure (e.g., A-B-C ordering of horizons) are a basis for research methods and our understanding of ecosystem structure and function in general. A general understanding of how urban soils differ from non-urban soils vertically is needed to inform urban research methods and advance our knowledge of urban ecosystems. We performed a soil taxonomic assessment of 391 deep soil cores (up to 5-m) collected in 11 cities across the U.S. and Puerto Rico. The likely soil series in the absence of urbanization was identified for each soil core and comparison soil taxonomy data for agricultural and wildlands land uses soils of the same soil series was gathered from the NASIS database. We hypothesized that urbanization has modified the vertical arrangement of soil horizons and decreased their vertical complexity (e.g., degree of horizonation). In addition, we hypothesized that soils in each city are becoming more like each other and less like their pre-urbanization soils. Urban soils had fewer soil horizons than their non-urban references; specifically, urban soils had two fewer distinct genetic horizons in the top meter of soil. B horizons were commonly lost or reduced in extent as A horizons deepened and C horizons shallowed in urban relative to reference soils. The order of horizons was also different from reference and theoretical soil structure. Namely A-C transitions with an absence of B horizons was more common in urban than non-urban soils. If these patterns hold across more cities, our results indicate a need to revisit the conventional predictions of vertical soil structure for understanding urban ecosystems. Finally, we found that several attributes for urban soils with evidence of significant disturbance associated with urbanization were converging across cities. Similar findings have been found for surface soils; here we show the structure of urban soil convergence at greater soil depths than previously reported.

Examining the influence of urban definition when assessing relative safety of drinking-water in Nigeria.

PubMed

Christenson, Elizabeth; Bain, Robert; Wright, Jim; Aondoakaa, Stephen; Hossain, Rifat; Bartram, Jamie

2014-08-15

Reducing inequalities is a priority from a human rights perspective and in water and public health initiatives. There are periodic calls for differential national and global standards for rural and urban areas, often justified by the suggestion that, for a given water source type, safety is worse in urban areas. For instance, initially proposed post-2015 water targets included classifying urban but not rural protected dug wells as unimproved. The objectives of this study were to: (i) examine the influence of urban extent definition on water safety in Nigeria, (ii) compare the frequency of thermotolerant coliform (TTC) contamination and prevalence of sanitary risks between rural and urban water sources of a given type and (iii) investigate differences in exposure to contaminated drinking-water in rural and urban areas. We use spatially referenced data from a Nigerian national randomized sample survey of five improved water source types to assess the extent of any disparities in urban-rural safety. We combined the survey data on TTC and sanitary risk with map layers depicting urban versus rural areas according to eight urban definitions. When examining water safety separately for each improved source type, we found no significant urban-rural differences in TTC contamination and sanitary risk for groundwater sources (boreholes and protected dug wells) and inconclusive findings for piped water and stored water. However, when improved and unimproved source types were combined, TTC contamination was 1.6 to 2.3 times more likely in rural compared to urban water sources depending on the urban definition. Our results suggest that different targets for urban and rural water safety are not justified and that rural dwellers are more exposed to unsafe water than urban dwellers. Additionally, urban-rural analyses should assess multiple definitions or indicators of urban to assess robustness of findings and to characterize a gradient that disaggregates the urban-rural dichotomy. Copyright © 2014 Elsevier B.V. All rights reserved.

The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xiaoma; Zhou, Yuyu; Asrar, Ghassem R.

Abstract: Urban heat island (UHI), a major concern worldwide, affects human health and energy use. With current and anticipated rapid urbanization, improved understanding of the response of UHI to urbanization is important for impact analysis and developing effective adaptation measures and mitigation strategies. Current studies mainly focus on a single or a few big cities and knowledge on the response of UHI to urbanization for large areas is very limited. Modelling UHI caused by urbanization for large areas that encompass multiple metropolitans remains a major scientific challenge/opportunity. As a major indicator of urbanization, urban area size lends itself well formore » representation in prognostic models to investigate the impacts of urbanization on UHI and the related socioeconomic and environmental effects. However, we have little knowledge on how UHI responds to the increase of urban area size, namely urban expansion, and its spatial and temporal variation over large areas. In this study, we investigated the relationship between surface UHI (SUHI) and urban area size in the climate and ecological context, and its spatial and temporal variations, based on a panel analysis of about 5000 urban areas of 10 km2 or larger, in the conterminous U.S. We found statistically significant positive relationship between SUHI and urban area size, and doubling the urban area size led to a SUHI increase of higher than 0.7 °C. The response of SUHI to the increase of urban area size shows spatial and temporal variations, with stronger SUHI increase in the Northern region of U.S., and during daytime and summer. Urban area size alone can explain as much as 87% of the variance of SUHI among cities studied, but with large spatial and temporal variations. Urban area size shows higher association with SUHI in regions where the thermal characteristics of land cover surrounding the urban are more homogeneous, such as in Eastern U.S., and in the summer months. This study provides a practical approach for large-scale assessment and modeling of the impact of urbanization on SUHI, both spatially and temporally, for developing mitigation/adaptation measures, especially in anticipated warmer climate conditions for the rest of this century.« less

Town and country reptiles: A review of reptilian responses to urbanization.

PubMed

French, Susannah S; Webb, Alison C; Hudson, Spencer B; Virgin, Emily E

2018-06-04

The majority of the world population is now inhabiting urban areas, and with staggering population growth urbanization is also increasing. While work studying the effects of changing landscapes and specific urban pressures on wildlife is beginning to amass, the majority of this work focuses on avian or mammalian species. However, the effects of urbanization likely vary substantially across taxonomic groups due to differences in habitat requirements and life history. The current paper aims first to broaden the review of urban effects across reptilian species; second, to summarize the responses of reptilian fauna to specific urban features; and third, to assess the directionality of individual and population level responses to urbanization in reptile species. Based on our findings, urban research in reptilian taxa is lacking in the following areas: 1) investigating interactive or additive urban factors 2) measuring multiple morphological, behavioral and physiological endpoints within an animal, 3) linking individual to population-level responses, and 4) testing genetic/genomic differences across an urban environment as evidence for selective pressures.

[A review on urban metabolism research based on physical space entities for environmental management].

PubMed

Liu, Ye; Liu, Dan

2015-07-01

Urban metabolism is a basic theory for coping with global environmental problems, which is coherent with the aims of national environmental management. This paper analyzed the concept of urban metabolism, and pointed out the meaning for urban metabolism in physical space entities; reviewed the current methods for urban metabolism and its merits and shortages; analyzed the system boundaries, connotation, and methodologies; and summarized the advances on urban meta-bolism practices in physical space entities. At last, we made conclusions that there were shortages, including conception system, basic theory system, and interdisciplinary integrated theory system in current urban metabolism research, and the current cases studied in urban metabolism were limited and not suitable to the harmony development between society, economy, and environment. In the future, we need to strengthen comparison between different case studies from different countries, develop the prior modes of typical urban metabolism research, identify the mechanism for urban ecosystem, and strengthen the spatial decision support system of environmental management taking urban spatial entity spaces as units.

An approach to evaluate the intra-urban thermal variability in summer using an urban indicator.

PubMed

Massetti, Luciano; Petralli, Martina; Brandani, Giada; Orlandini, Simone

2014-09-01

Urban planners and managers need tools to evaluate the performance of the present state and future development of cities in terms of comfort and quality of life. In this paper, an approach to analyse the intra-urban summer thermal variability, using an urban planning indicator, is presented. The proportion of buildings and concrete surfaces in a specific buffer area are calculated. Besides, the relationship between urban and temperature indicators is investigated and used to produce thermal maps of the city. This approach is applied to the analysis of intra-urban variability in Florence (Italy), of two thermal indices (heat index and cooling degree days) used to evaluate impacts on thermal comfort and energy consumption for indoor cooling. Our results suggest that urban planning indicators can describe intra-urban thermal variability in a way that can easily be used by urban planners for evaluating the effects of future urbanization scenarios on human health. Copyright © 2014 Elsevier Ltd. All rights reserved.

Monitoring the transformation of Yogyakarta’s urban form using remote sensing and Geographic Information System

NASA Astrophysics Data System (ADS)

Rozano, B.; Yan, W.

2018-04-01

Urban form transformation can be seen as the results of urbanization spatially, where the land changed into an urbanized one. Monitoring its changes, however, require many human and financial resources. Accordingly, this research aims to identify urban form transformation using GIS/remote sensing and its spatial implications to the peri-urban area. In order to analyze the land cover changes, this research uses multispectral images from 1990-2016 for built-up extraction using New Built Up Index (NBUI) analysis and population data 1996-2015 combined with primary data from the respondents and key informants. Based on the analysis, it is seen that the compacted Yogyakarta Urban Area scattered predominantly to the Northern part of its periphery with the increase of urban area from 21.19% in 1990 to 50.91% in 2017. While this urbanization is an on-going process, the population of urban core showed a de-concentration phenomenon in 2015, spreading to its periphery causing some negative implications to the peri-urban area.

The urban public space betterment and land use sustainability Under the human behavior

NASA Astrophysics Data System (ADS)

Zhao, Xiaofan; Ji, Yanning

2018-02-01

This paper analyzes the differences between Chinese and western public life and environmental behavior habits. Identify specific needs for Chinese urban public Spaces. At the same time, the paper analyzes the problems related to urban construction in China, including micro-land use, transportation and urban pattern. The solution of Chinese urban public space layout is proposed and the prospects of sustainable urban public space. Urban betterment are prospected in the future.

Persistent Monitoring of Urban Infrasound Phenomenology-Report 2: Investigation of Structural Infrasound Signals in an Urban Environment

DTIC Science & Technology

2016-11-01

space houses, etc.), and the unique weather environments that occur in the Urban Heat Island. A detailed urban terrain model was developed in a...affected by urban infrastructure (large buildings, roadways, densely space houses, etc.). A detailed urban terrain model was developed ERDC TR-15-5...different points in the model provided insight to complex propagation paths characteristic of urban environments. ERDC TR-15-5; Report 2 20 4

Fertility and Child Mortality in Urban West Africa: Leveraging geo-referenced data to move beyond the urban/rural dichotomy

PubMed Central

Corker, Jamaica

2016-01-01

Demographic research in sub-Saharan Africa (SSA) has long relied on a blunt urban/rural dichotomy that may obscure important inter-urban fertility and mortality differentials. This paper uses Demographic and Health Survey (DHS) geo-referenced data to look beyond the simple urban/rural division by spatially locating survey clusters along an urban continuum and producing estimates of fertility and child mortality by four city size categories in West Africa. Results show a gradient in urban characteristics and demographic outcomes: the largest cities are the most advantaged and smaller cities least advantaged with respect to access to urban amenities, lower fertility and under-5 survival rates. There is a difference in the patterns of fertility and under-five survival across urban categories, with fertility more linearly associated with city size while the only significant distinction for under-5 survival in urban areas is broadly between the larger and smaller cities. Notably, the small urban “satellite cities” that are adjacent to the largest cities have the most favorable outcomes of all categories. Although smaller urban areas have significantly lower fertility and child mortality than rural areas, in some cases this difference is nearly as large between the smallest and largest urban areas. These results are used to argue for the need to give greater consideration to employing an urban continuum in demographic research. PMID:28943812

Maternal responses to childhood fevers: a comparison of rural and urban residents in coastal Kenya.

PubMed

Molyneux, C S; Mung'Ala-Odera, V; Harpham, T; Snow, R W

1999-12-01

Urbanization is an important demographic phenomenon in sub-Saharan Africa, and rural-urban migration remains a major contributor to urban growth. In a context of sustained economic recession, these demographic processes have been associated with a rise in urban poverty and ill health. Developments in health service provision need to reflect new needs arising from demographic and disease ecology change. In malaria-endemic coastal Kenya, we compared lifelong rural (n = 248) and urban resident (n = 284) Mijikenda mothers' responses to childhood fevers. Despite marked differences between the rural and urban study areas in demographic structure and physical access to biomedical services, rural and urban mothers' treatment-seeking patterns were similar: most mothers sought only biomedical treatment (88%). Shop-bought medicines were used first or only in 69% of the rural and urban fevers that were treated, and government or private clinics were contacted in 49%. A higher proportion of urban informal vendors stocked prescription-only drugs, and urban mothers more likely to contact a private than a government facility. We conclude that improving self-treatment has enormous potential to reduce morbidity and mortality in low-income urban areas, as has frequently been argued for rural areas. However, because of the underlying socio-economic, cultural and structural differences between rural and urban areas, rural approaches to tackle this may have to be modified in urban environments.

Is there an urban advantage in child survival in sub-saharan Africa? Evidence from 18 countries in the 1990s.

PubMed

Bocquier, Philippe; Madise, Nyovani Janet; Zulu, Eliya Msiyaphazi

2011-05-01

Evidence of higher child mortality of rural-to-urban migrants compared with urban nonmigrants is growing. However, less attention has been paid to comparing the situation of the same families before and after they migrate with the situation of urban-to-rural migrants. We use DHS data from 18 African countries to compare child mortality rates of six groups based on their mothers' migration status: rural nonmigrants; urban nonmigrants; rural-to-urban migrants before and after they migrate; and urban-to-rural migrants before and after they migrate. The results show that rural-to-urban migrants had, on average, lower child mortality before they migrated than rural nonmigrants, and that their mortality levels dropped further after they arrived in urban areas. We found no systematic evidence of higher child mortality for rural-to-urban migrants compared with urban nonmigrants. Urban-to-rural migrants had higher mortality in the urban areas, and their move to rural areas appeared advantageous because they experienced lower or similar child mortality after living in rural areas. After we control for known demographic and socioeconomic correlates of under-5 mortality, the urban advantage is greatly reduced and sometimes reversed. The results suggest that it may not be necessarily the place of residence that matters for child survival but, rather, access to services and economic opportunities.

A Century of the Evolution of the Urban Area in Shenyang, China

PubMed Central

Liu, Miao; Xu, Yanyan; Hu, Yuanman; Li, Chunlin; Sun, Fengyun; Chen, Tan

2014-01-01

Analyzing spatiotemporal characteristics of the historical urbanization process is essential in understanding the dynamics of urbanization and scientifically planned urban development. Based on historical urban area maps and remote sensing images, this study examined the urban expansion of Shenyang from 1910 to 2010 using area statistics, typology identification, and landscape metrics approaches. The population and gross domestic product were analyzed as driving factors. The results showed that the urban area of Shenyang increased 43.39-fold during the study period and that the growth rate has accelerated since the 1980s. Three urban growth types were distinguished: infilling, edge-expansion, and spontaneous growth. Edge-expansion was the primary growth type. Infilling growth became the main growth type in the periods 1946–70, 1988–97, and 2004–10. Spontaneous growth was concentrated in the period of 1997 to 2000. The results of landscape metrics indicate that the urban landscape of Shenyang originally was highly aggregated, but has become increasingly fragmented. The urban fringe area was the traditional hot zone of urbanization. Shenyang was mainly located north of the Hun River before 1980; however, the south side of the river has been the hot zone of urbanization since the 1980s. The increase of urban area strongly correlated with the growth of GDP and population. Over a long time scale, the urbanization process has been affected by major historical events. PMID:24893167

Urban and non-urban differences in community living and participation among individuals with serious mental illnesses.

PubMed

Townley, Greg; Brusilovskiy, Eugene; Salzer, Mark S

2017-03-01

Despite a wealth of studies examining the relationship between urbanicity (i.e., living in an urban area) and psychological distress, there is a paucity of research examining the relationship between urbanicity, community living, and community participation of adults with serious mental illnesses. This study addresses this knowledge gap by assessing urban and non-urban differences in community participation, sense of community, mental health stigma, and perceptions of the neighborhood environment among individuals with serious mental illnesses living independently throughout the United States. A total of 300 individuals with serious mental illnesses recruited from 21 outpatient mental health service organizations in 15 states completed a phone survey about their community living and participation experiences. Urbanicity was examined at two spatial scales (block group and county), and independent-samples t-tests were employed to assess urban and non-urban differences in community living and participation variables. Levels of community participation and perceptions of neighborhood quality and crime were higher in urban block groups; sense of community was higher in urban counties; and perceptions of mental health stigma were higher in non-urban counties. Results inform the methodological literature on best practices for assessing urbanicity, as well as interventions aimed at increasing community participation and improving aspects of the built and social environment that affect individuals who experience mental health distress. Copyright © 2017 Elsevier Ltd. All rights reserved.

CADDIS Volume 2. Sources, Stressors and Responses: Urbanization - Riparian/Channel Alteration

EPA Pesticide Factsheets

Introduction to riparian and channel alteration associated with urbanization, summary of how riparian urbanization affects channel morphology, summary of how urbanization affects riparian hydrology, overview of stream burial associated with urbanization.

"Urban, but Not Too Urban": Unpacking Teachers' Desires to Teach Urban Students

ERIC Educational Resources Information Center

Watson, Dyan

2011-01-01

This study explores 16 novice, urban-trained teachers' evaluations of their current schools. Findings suggest that teachers used the perceived behaviors, values, and beliefs of students to measure how urban a student was and, therefore, to guide their expectations and satisfaction of their placements. The less urban the students were perceived to…

Removal of Ozone by Urban and Peri-Urban Forests: Evidence from Laboratory, Field, and Modeling Approaches

Treesearch

Carlo Calfapietra; Arianna Morani; Gregorio Sgrigna; Sara Di Giovanni; Valerio Muzzini; Emanuele Pallozzi; Gabriele Guidolotti; David Nowak; Silvano Fares

2016-01-01

A crucial issue in urban environments is the interaction between urban trees and atmospheric pollution, particularly ozone (O3). Ozone represents one of the most harmful pollutants in urban and peri-urban environments, especially in warm climates. Besides the large interest in reducing anthropogenic and biogenic precursors of O3...

The Impacts of Urbanization on Meteorology and Air Quality in the Los Angeles Basin

NASA Astrophysics Data System (ADS)

Li, Y.; Zhang, J.; Sailor, D.; Ban-Weiss, G. A.

2017-12-01

Urbanization has a profound influence on regional meteorology in mega cities like Los Angeles. This influence is driven by changes in land surface physical properties and urban processes, and their corresponding influence on surface-atmosphere coupling. Changes in meteorology from urbanization in turn influences air quality through weather-dependent chemical reaction, pollutant dispersion, etc. Hence, a real-world representation of the urban land surface properties and urban processes should be accurately resolved in regional climate-chemistry models for better understanding the role of urbanization on changing urban meteorology and associated pollutant dynamics. By incorporating high-resolution land surface data, previous research has improved model-observation comparisons of meteorology in urban areas including the Los Angeles basin, and indicated that historical urbanization has increased urban temperatures and altered wind flows significantly. However, the impact of urban expansion on air quality has been less studied. Thus, in this study, we aim to evaluate the effectiveness of resolving high-resolution heterogeneity in urban land surface properties and processes for regional weather and pollutant concentration predictions. We coupled the Weather Research and Forecasting model with Chemistry to the single-layer Urban Canopy Model to simulate a typical summer period in year 2012 for Southern California. Land cover type and urban fraction were determined from National Land Cover Data. MODIS observations were used to determine satellite-derived albedo, green vegetation fraction, and leaf area index. Urban morphology was determined from GIS datasets of 3D building geometries. An urban irrigation scheme was also implemented in the model. Our results show that the improved model captures the diurnal cycle of 2m air temperature (T2) and Ozone (O3) concentrations. However, it tends to overestimate wind speed and underestimate T2, which leads to an underestimation of O3 and fine particulate matter concentrations. By comparing simulations assuming current land cover of the Los Angeles basin versus pre-urbanization land cover, we find that land cover change through urbanization has led to important shifts in regional air pollution via the aforementioned physical and chemical mechanisms.

Differential associations of urbanicity and income with physical activity in adults in urbanizing China: findings from the population-based China Health and Nutrition Survey 1991-2009.

PubMed

Attard, Samantha M; Howard, Annie-Green; Herring, Amy H; Zhang, Bing; Du, Shufa; Aiello, Allison E; Popkin, Barry M; Gordon-Larsen, Penny

2015-12-12

High urbanicity and income are risk factors for cardiovascular-related chronic diseases in low- and middle-income countries, perhaps due to low physical activity (PA) in urban, high income areas. Few studies have examined differences in PA over time according to income and urbanicity in a country experiencing rapid urbanization. We used data from the China Health and Nutrition Survey, a population-based cohort of Chinese adults (n = 20,083; ages 18-75y) seen a maximum of 7 times from 1991-2009. We used sex-stratified, zero-inflated negative binomial regression models to examine occupational, domestic, leisure, travel, and total PA in Chinese adults according to year, urbanicity, income, and the interactions among urbanicity, income, and year, controlling for age and region of China. We showed larger mean temporal PA declines for individuals living in relatively low urbanicity areas (1991: 500 MET-hours/week; 2009: 300 MET-hours/week) compared to high urbanicity areas (1991: 200 MET-hours/week; 2009: 125 MET-hours/week). In low urbanicity areas, the association between income and total PA went from negative in 1991 (p < 0.05) to positive by 2000 (p < 0.05). In relatively high urbanicity areas, the income-PA relationship was positive at all time points and was statistically significant at most time points after 1997 (p < 0.05). Leisure PA was the only domain of PA that increased over time, but >95% of individuals in low urbanicity areas reported zero leisure PA at each time point. Our findings show changing associations for income and urbanicity with PA over 18 years of urbanization. Total PA was lower for individuals living in more versus less urban areas at all time points. However, these differences narrowed over time, which may relate to increases in individual-level income in less urban areas of China with urbanization. Low-income individuals in higher urbanicity areas are a particularly critical group to target to increase PA in China.

Effects of Green Space and Land Use/Land Cover on Urban Heat Island in a Subtropical Mega-city in China

NASA Astrophysics Data System (ADS)

Qiu, G. Y.; Li, X.; Li, H.; Guo, Q.

2014-12-01

With the quick expansion of urban in size and population, its urban heat island intensity (UHII, expressed as the temperature difference between urban and rural areas) increased rapidly. However, very few studies could quantitatively reveal the effects of green space and land use/land cover (LULC) on urban thermal environment because of lacking of the detailed measurement. This study focuses on quantifying the effects of green space and LULC on urban Heat Island (UHI) in Shenzhen, a mega subtropical city in China. Extensive measurements (air temperature and humidity) were made by mobile traverse method in a transect of 8 km in length, where a variety of LULC types were included. Measurements were carried out at 2 hours interval for 2 years (totally repeated for 7011 times). According to LULC types, we selected 5 different LULC types for studying, including water body, village in the city, shopping center (commercial area), urban green space (well-vegetated area) and suburb (forest). The main conclusions are obtained as follows: (1) The temperature difference between the 5 different urban landscapes is obvious, i.e. shopping center > village in the city > urban water body > urban green space > suburb; (2) Air temperature and UHII decreases linearly with the increase of green space in urban; (3) Green space and water body in urban have obvious effects to reduce the air temperature by evapotranspiration. Compared to the commercial areas, urban water body can relieve the IUHI by 0.9℃, while the urban green space can relieve the IUHI by 1.57℃. The cooling effect of the urban green space is better than that of the urban water body; (4) Periodic activity of human being has obvious effects on urban air temperature. The UHII on Saturday and Sunday are higher than that from Monday to Friday, respectively higher for 0.65, 0.57, 0.26 and 0.21℃. Thursday and Friday have the minimum air temperature and UHII. These results indicate that increase in urban evapotranspiration by increasing green space could be a useful way to improve urban thermal environment and mitigation of UHI.

Urban geomorphological heritage - A new field of research

NASA Astrophysics Data System (ADS)

Reynard, Emmanuel; Pica, Alessia; Coratza, Paola

2017-04-01

Urbanization is one of the major challenges that the world faces. In 2015, 54% of the world population was living in urban areas and in some countries this percentage is close to 100% (Singapore 100%; Qatar 99%; Belgium 98%). In several parts of the world annual urbanization rates exceed 5% (e.g. Oman 8.54%; Rwanda 6.43%; Burkina Faso 5.87%), which means that urban sprawl is a widespread phenomenon. Urbanization and correlated infrastructure building highly impact and sometimes completely destroy natural landforms. Geomorphological heritage research has traditionally focused on rural or natural regions, in particular protected areas (nature parks, geoparks). We consider that urban areas, which have been poorly investigated until now, are particularly interesting in a geomorphological heritage point of view for almost three reasons: (i) The geomorphological context (site) of some cities is part of their "image" and their fame (e.g. the sugarloaf of Rio de Janeiro); (ii) Urban sprawl often interacts with landforms, which addresses the challenge of geoheritage protection in fast urbanizing areas; (iii) Cities are often tourist destinations, which creates a potential for a geotourist promotion of their geomorphological heritage. This study addresses the main challenges research on geomorphological heritage is facing in urban contexts: (i) the complex interrelationships between natural landforms and urban forms; (ii) the partial or total invisibility of landforms and sediments that are covered or destroyed by urban infrastructures; (iii) man-made landforms as part of urban geomorphological heritage; (iv) the suitability of some landforms (valleys, gullies, mounts) for specific urban uses; (v) the geomorphic constraints of landforms on urban development; and (vi) the importance of some landforms for the urban landscape and the image of the cities. To address these challenges a methodological framework is proposed, which combines: (i) the geomorphological analysis of the urban landscape through geomorphological mapping (with use of a specific legend for man-made landforms) and geohistorical analysis of landscape evolution (historical maps processing); (ii) the selection, characterization and assessment of urban geomorphosites; (iii) proposals for the conservation and promotion (geotourism) of the urban geomorphological heritage.

Building-Based Analysis of the Spatial Provision of Urban Parks in Shenzhen, China.

PubMed

Gao, Wenxiu; Lyu, Qiang; Fan, Xiang; Yang, Xiaochun; Liu, Jiangtao; Zhang, Xirui

2017-12-06

Urban parks provide important environmental, social, and economic benefits to people and urban areas. The literature demonstrates that proximity to urban parks is one of the key factors influencing people's willingness to use them. Therefore, the provision of urban parks near residential areas and workplaces is one of the key factors influencing quality of life. This study designed a solution based on the spatial association between urban parks and buildings where people live or work to identify whether people in different buildings have nearby urban parks available for their daily lives. A building density map based on building floor area (BFA) was used to illustrate the spatial distribution of urban parks and five indices were designed to measure the scales, service coverage and potential service loads of urban parks and reveal areas lacking urban park services in an acceptable walking distance. With such solution, we investigated the provision of urban parks in ten districts of Shenzhen in China, which has grown from several small villages to a megacity in only 30 years. The results indicate that the spatial provision of urban parks in Shenzhen is not sufficient since people in about 65% of the buildings cannot access urban parks by walking 10-min. The distribution and service coverage of the existing urban parks is not balanced at the district level. In some districts, the existing urban parks have good numbers of potential users and even have large service loads, while in some districts, the building densities surrounding the existing parks are quite low and at the same time there is no urban parks nearby some high-density areas.

A new framework for modeling urban land expansion in peri-urban area by combining multi-source datasets and data assimilation

NASA Astrophysics Data System (ADS)

Zhang, Z.; Xiao, R.; Li, X.

2015-12-01

Peri-urban area is a new type region under the impacts of both rural Industrialization and the radiation of metropolitan during rapid urbanization. Due to its complex natural and social characteristics and unique development patterns, many problems such as environmental pollution and land use waste emerged, which became an urgent issue to be addressed. Study area in this paper covers three typical peri-urban districts (Pudong, Fengxian and Jinshan), which around the Shanghai inner city. By coupling cellular automata and multi-agent system model as the basic tools, this research focus on modelling the urban land expansion and driving mechanism in peri-urban area. The big data is aslo combined with the Bayesian maximum entropy method (BME) for spatiotemporal prediction of multi-source data, which expand the dataset of urban expansion models. Data assimilation method is used to optimize the parameters of the coupling model and minimize the uncertainty of observations, improving the precision of future simulation in peri-urban area. By setting quantitative parameters, the coupling model can effectively improve the simulation of the process of urban land expansion under different policies and management schemes, in order to provide scientificimplications for new urbanization strategy. In this research, we precise the urban land expansion simulation and prediction for peri-urban area, expand the scopes and selections of data acquisition measurements and methods, develop the new applications of the data assimilation method in geographical science, provide a new idea for understanding the inherent rules of urban land expansion, and give theoretical and practical support for the peri-urban area in urban planning and decision making.

Building-Based Analysis of the Spatial Provision of Urban Parks in Shenzhen, China

PubMed Central

Gao, Wenxiu; Lyu, Qiang; Fan, Xiang; Liu, Jiangtao; Zhang, Xirui

2017-01-01

Urban parks provide important environmental, social, and economic benefits to people and urban areas. The literature demonstrates that proximity to urban parks is one of the key factors influencing people’s willingness to use them. Therefore, the provision of urban parks near residential areas and workplaces is one of the key factors influencing quality of life. This study designed a solution based on the spatial association between urban parks and buildings where people live or work to identify whether people in different buildings have nearby urban parks available for their daily lives. A building density map based on building floor area (BFA) was used to illustrate the spatial distribution of urban parks and five indices were designed to measure the scales, service coverage and potential service loads of urban parks and reveal areas lacking urban park services in an acceptable walking distance. With such solution, we investigated the provision of urban parks in ten districts of Shenzhen in China, which has grown from several small villages to a megacity in only 30 years. The results indicate that the spatial provision of urban parks in Shenzhen is not sufficient since people in about 65% of the buildings cannot access urban parks by walking 10-min. The distribution and service coverage of the existing urban parks is not balanced at the district level. In some districts, the existing urban parks have good numbers of potential users and even have large service loads, while in some districts, the building densities surrounding the existing parks are quite low and at the same time there is no urban parks nearby some high-density areas. PMID:29211046

Diabetes and cardiometabolic risk factors in Cambodia: Results from two screening studies.

PubMed

Wagner, Julie; Naranjo, Diana; Khun, Touch; Seng, Serey; Horn, Ien S; Suttiratana, Sakinah C; Keuky, Lim

2018-02-01

Despite growing attention to diabetes throughout Asia, data from Southeast Asia are limited. This article reports rates of diabetes, hypertension, and obesity in Cambodia. Two studies were conducted across different regions of Cambodia: (i) a 2012 screening study across urban, semi-urban, and rural areas that used point-of-care capillary glucose for determination of diabetes (n = 13 997); and (ii) a 2005 epidemiological study with random selection from two main urban areas that used oral glucose tolerance tests for determination of diabetes (n = 1863). Blood pressure and anthropometrics were also measured. In the screening study, rates of diabetes were significantly higher in urban than rural sites, with intermediate rates in semi-urban areas. There was a significant dose-response effect for urbanicity on overweight, obesity, and waist:hip ratio, with higher rates for urban versus semi-urban and for semi-urban versus rural locales. Rural sites had the lowest rates of hypertension, followed by urban and semi-urban sites. Among people who screened positive for diabetes, there was a dose-response effect for urbanicity on undiagnosed diabetes; rates of previously undiagnosed diabetes were lowest in urban (51%), followed by semi-urban (55%) and rural (67%) locales. Rural participants reported the highest rates of smoking and alcohol use. In the urban epidemiological study, prevalence rates of diabetes and impaired glucose tolerance were approximately 10%, indicating a prevalence of total glucose intolerance of approximately 20%. In Cambodia, diabetes rates are high among urban residents and undiagnosed diabetes is highest among rural residents. A country-wide public health response is urgently needed; as development continues, rates of diabetes are expected to rise. © 2017 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Third-world development: urbanizing for the future.

PubMed

Mcilwaine, C

1997-01-01

This article reviews some issues reflected in the 1996 UN Habitat II agenda and recent research on urbanization. The themes of the 1996 Habitat conference were urban development, urban poverty, and governance, civil society, and social capital. It is expected that over 50% of total world population will live in cities in the year 2000. Cities are viewed both as engines of economic growth and centers of severe economic, environmental, and social problems. There is some disagreement about whether cities are rational economic structures or what the World Bank's urban agenda is and its relationship with macroeconomic policy. Discussions of global urban issues are criticized for their neglect of issues of equity and poverty, cultural diversity, and identity and representation. Habitat II also stressed urban sustainability. There is growing recognition that urban management involves more than the "Brown Agenda" of environmental and physical aspects of urban growth. Recent studies identify how politics and power affect people's access to basic urban services. Urban economic activity can also contribute to environmental problems. Urban growth affects the provision of health services. Although there is not a consensus on the role of cities in expanding economic and social development and the best management practices, there is sufficient evidence to indicate that urban processes are varied throughout the developing world. The links between urban and rural areas differentiate cities and expose the need to understand the role of intermediate urban areas surrounding and between larger cities. Poverty has become increasingly urbanized, but the extent of poverty is unknown. Habitat II was an unprecedented effort to engage nongovernment groups, local government staff, trade unions, and the private sector and to emphasize community participation. Networks of trust and reciprocity are key to solving poverty, inequality, and disempowerment problems.

Urbanization effects on fishes and habitat quality in a southern Piedmont river basin

USGS Publications Warehouse

Walters, D.M.; Freeman, Mary C.; Leigh, D.S.; Freeman, B.J.; Pringle, C.P.; Brown, Larry R.; Gray, Robert H.; Hughes, Robert H.; Meador, Michael

2005-01-01

We quantified the relationships among urban land cover, fishes, and habitat quality to determine how fish assemblages respond to urbanization and if a habitat index can be used as an indirect measure of urban effects on stream ecosystems. We sampled 30 wadeable streams along an urban gradient (5?37% urban land cover) in the Etowah River basin, Georgia. Fish assemblages, sampled by electrofishing standardized stream reaches, were assessed using species richness, density, and species composition metrics. Habitat quality was scored using the Rapid Habitat Assessment Protocol (RHAP) of the U.S. Environmental Protection Agency. Urban land cover (including total, high-, and low-density urban) was estimated for the drainage basin above each reach. A previous study of these sites indicated that stream slope and basin area were strongly related to local variation in assemblage structure. We used multiple linear regression (MLR) analysis to account for this variation and isolate the urban effect on fishes. The MLR models indicated that urbanization lowered species richness and density and led to predictable changes in species composition. Darters and sculpin, cyprinids, and endemics declined along the urban gradient whereas centrarchids persisted and became the dominant group. The RHAP was not a suitable indicator of urban effects because RHAP-urban relationships were confounded by an overriding influence of stream slope on RHAP scores, and urban-related changes in fish assemblage structure preceded gross changes in stream habitat quality. Regression analysis indicated that urban effects on fishes accrue rapidly (<10 years) and are detectable at low levels (~5?10% urbanization). We predict that the decline of endemics and other species will continue and centrarchid-dominated streams will become more common as development proceeds within the Etowah basin.

Accounting for urban biogenic fluxes in regional carbon budgets.

PubMed

Hardiman, Brady S; Wang, Jonathan A; Hutyra, Lucy R; Gately, Conor K; Getson, Jackie M; Friedl, Mark A

2017-08-15

Many ecosystem models incorrectly treat urban areas as devoid of vegetation and biogenic carbon (C) fluxes. We sought to improve estimates of urban biomass and biogenic C fluxes using existing, nationally available data products. We characterized biogenic influence on urban C cycling throughout Massachusetts, USA using an ecosystem model that integrates improved representation of urban vegetation, growing conditions associated with urban heat island (UHI), and altered urban phenology. Boston's biomass density is 1/4 that of rural forests, however 87% of Massachusetts' urban landscape is vegetated. Model results suggest that, kilogram-for-kilogram, urban vegetation cycles C twice as fast as rural forests. Urban vegetation releases (R E ) and absorbs (GEE) the equivalent of 11 and 14%, respectively, of anthropogenic emissions in the most urban portions of the state. While urban vegetation in Massachusetts fully sequesters anthropogenic emissions from smaller cities in the region, Boston's UHI reduces annual C storage by >20% such that vegetation offsets only 2% of anthropogenic emissions. Asynchrony between temporal patterns of biogenic and anthropogenic C fluxes further constrains the emissions mitigation potential of urban vegetation. However, neglecting to account for biogenic C fluxes in cities can impair efforts to accurately monitor, report, verify, and reduce anthropogenic emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

Differences in Age-Standardized Mortality Rates for Avoidable Deaths Based on Urbanization Levels in Taiwan, 1971–2008

PubMed Central

Chen, Brian K.; Yang, Chun-Yuh

2014-01-01

The World is undergoing rapid urbanization, with 70% of the World population expected to live in urban areas by 2050. Nevertheless, nationally representative analysis of the health differences in the leading causes of avoidable mortality disaggregated by urbanization level is lacking. We undertake a study of temporal trends in mortality rates for deaths considered avoidable by the Concerted Action of the European Community on Avoidable Mortality for four different levels of urbanization in Taiwan between 1971 and 2008. We find that for virtually all causes of death, age-standardized mortality rates (ASMRs) were lower in more urbanized than less urbanized areas, either throughout the study period, or by the end of the period despite higher rates in urbanized areas initially. Only breast cancer had consistently higher AMSRs in more urbanized areas throughout the 38-year period. Further, only breast cancer, lung cancer, and ischemic heart disease witnessed an increase in ASMRs in one or more urbanization categories. More urbanized areas in Taiwan appear to enjoy better indicators of health outcomes in terms of mortality rates than less urbanized areas. Access to and the availability of rich healthcare resources in urban areas may have contributed to this positive result. PMID:24503974

Characteristics of peri-urbanization of a secondary city: a challenge in recent urban development

NASA Astrophysics Data System (ADS)

Rahayu, P.; Mardiansjah, F. H.

2018-03-01

Urbanization process creates a tremendous spatial phenomenon since the last century. Especially for the country of the South, the phenomenon is still relevant to the situation today and the processes will still going until the foreseeable future. The metropolitan-based of urbanization process involves the development of peri-urban areas, which could be defined as transitional zones between city and rural areas characterized by integrated mixed-structures of agricultural and non-agricultural activities. This article reveals the characteristics of periurbanization process of an emerging secondary city in Java, which uses Surakarta, the second largest city in Central Java Province based on the population size, as the case. During the last ten years, there have been significant changes in peri-urban areas regarding urban population, land use, and urban activities that strengthening the contribution of the urban component into peri-urban system.

The study of urban metabolism and its applications to urban planning and design.

PubMed

Kennedy, C; Pincetl, S; Bunje, P

2011-01-01

Following formative work in the 1970s, disappearance in the 1980s, and reemergence in the 1990s, a chronological review shows that the past decade has witnessed increasing interest in the study of urban metabolism. The review finds that there are two related, non-conflicting, schools of urban metabolism: one following Odum describes metabolism in terms of energy equivalents; while the second more broadly expresses a city's flows of water, materials and nutrients in terms of mass fluxes. Four example applications of urban metabolism studies are discussed: urban sustainability indicators; inputs to urban greenhouse gas emissions calculation; mathematical models of urban metabolism for policy analysis; and as a basis for sustainable urban design. Future directions include fuller integration of social, health and economic indicators into the urban metabolism framework, while tackling the great sustainability challenge of reconstructing cities. Copyright © 2010 Elsevier Ltd. All rights reserved.

Assessment of sustainable urban transport development based on entropy and unascertained measure.

PubMed

Li, Yancang; Yang, Jing; Shi, Huawang; Li, Yijie

2017-01-01

To find a more effective method for the assessment of sustainable urban transport development, the comprehensive assessment model of sustainable urban transport development was established based on the unascertained measure. On the basis of considering the factors influencing urban transport development, the comprehensive assessment indexes were selected, including urban economical development, transport demand, environment quality and energy consumption, and the assessment system of sustainable urban transport development was proposed. In view of different influencing factors of urban transport development, the index weight was calculated through the entropy weight coefficient method. Qualitative and quantitative analyses were conducted according to the actual condition. Then, the grade was obtained by using the credible degree recognition criterion from which the urban transport development level can be determined. Finally, a comprehensive assessment method for urban transport development was introduced. The application practice showed that the method can be used reasonably and effectively for the comprehensive assessment of urban transport development.

Natural hydrocarbons, urbanization, and urban ozone

NASA Technical Reports Server (NTRS)

Cardelino, C. A.; Chameides, W. L.

1990-01-01

The combined effects of emission control and urbanization, with its concomitant intensification of the urban heat island, on urban ozone concentrations are studied. The effect of temperature on ozone is considered, and attention is given to the temperature effect on ozone photochemistry. Model calculations suggest that ozone concentration enhancements are caused by the effect of temperature on the atmospheric chemistry of peroxyacetyl nitrate, as well as the temperature dependence of natural and anthropogenic hydrocarbon emissions. It is pointed out that, because of the sensitivity of urban ozone to local climatic conditions and the ability of trees to moderate summertime temperatures, the inadvertent removal of trees from urbanization can have an adverse effect on urban ozone concentration, while a temperature increase in the urban heat island caused by urbanization can essentially cancel out the ozone-reducing benefits obtained from a 50-percent reduction in anthropogenic hydrocarbon emissions.

Effects of urbanization on heavy metal accumulation in surface soils, Beijing.

PubMed

Wang, Meie; Liu, Rui; Chen, Weiping; Peng, Chi; Markert, Bernd

2018-02-01

Urbanization processes affect the accumulation of heavy metals in urban soils. Effects of urbanization on heavy metal accumulation in soils were studied using Beijing as an example. It has been suggested that the ecological function of vegetation covers shifting from natural to agricultural settings and then to urban greenbelts could increase the zinc (Zn) concentrations of soils successively. The Zn concentration of urban soils was significantly correlated to the percentage of the impervious land surface at the 500m×500m spatial scale. For urban parks, the age or years since the development accounted for 80% of the variances of cadmium (Cd) and Zn in soils. The population density, however, did not affect the heavy metal distributions in urban soils. To conclude, the urban age turned out to be a notable factor in quantifying heavy metal accumulation in urban soils. Copyright © 2017. Published by Elsevier B.V.

Urbanization and watershed sustainability: Collaborative simulation modeling of future development states

NASA Astrophysics Data System (ADS)

Randhir, Timothy O.; Raposa, Sarah

2014-11-01

Urbanization has a significant impact on water resources and requires a watershed-based approach to evaluate impacts of land use and urban development on watershed processes. This study uses a simulation with urban policy scenarios to model and strategize transferable recommendations for municipalities and cities to guide urban decisions using watershed ecohydrologic principles. The watershed simulation model is used to evaluation intensive (policy in existing built regions) and extensive (policy outside existing build regions) urban development scenarios with and without implementation of Best Management practices (BMPs). Water quantity and quality changes are simulated to assess effectiveness of five urban development scenarios. It is observed that optimal combination of intensive and extensive strategies can be used to sustain urban ecosystems. BMPs are found critical to reduce storm water and water quality impacts on urban development. Conservation zoning and incentives for voluntary adoption of BMPs can be used in sustaining urbanizing watersheds.

Model analysis of urbanization impacts on boundary layer meteorology under hot weather conditions: a case study of Nanjing, China

NASA Astrophysics Data System (ADS)

Chen, Lei; Zhang, Meigen; Wang, Yongwei

2016-08-01

The Weather Research and Forecasting (WRF) model, configured with a single-layer urban canopy model, was employed to investigate the influence of urbanization on boundary layer meteorological parameters during a long-lasting heat wave. This study was conducted over Nanjing city, East China, from 26 July to 4 August 2010. The impacts of urban expansion and anthropogenic heat (AH) release were simulated to quantify their effects on 2-m temperature, 2-m water vapor mixing ratio, and 10-m wind speed and heat stress index. Urban sprawl increased the daily 2-m temperature in urbanized areas by around 1.6 °C and decreased the urban diurnal temperature range (DTR) by 1.24 °C. The contribution of AH release to the atmospheric warming was nearly 22 %, but AH had little influence on the DTR. The urban regional mean surface wind speed decreased by about 0.4 m s-1, and this decrease was successfully simulated from the surface to 300 m. The influence of urbanization on 2-m water vapor mixing ratio was significant over highly urbanized areas with a decrease of 1.1-1.8 g kg-1. With increased urbanization ratio, the duration of the inversion layer was about 4 h shorter, and the lower atmospheric layer was less stable. Urban heat island (UHI) intensity was significantly enhanced when synthesizing both urban sprawl and AH release and the daily mean UHI intensity increased by 0.74 °C. Urbanization increased the time under extreme heat stress (about 40 %) and worsened the living environment in urban areas.

The comparative evidence for urban species sorting by anthropogenic noise

PubMed Central

Hu, Yang

2018-01-01

Anthropogenic noise is more intense at lower sound frequencies, which could decrease urban tolerance of animals with low-frequency vocalizations. Four large comparative studies tested whether anthropogenic noise filters bird species according to the sound frequencies they use and produced discrepant results. We reanalysed data from these studies to explain their different results. Urban tolerance of bird species (defined here as often occurring and breeding in cities) is very weakly related to urban preference or relative abundance (defined based on changes in population density from urban to nearby rural environments). Data on urban preference/abundance are potentially accurate for individual cities but differ among cities for the same species, whereas existing data on urban tolerance are coarser but provide a more global synthesis. Cross-species comparisons find a positive association between the sound frequency of song and urban tolerance, but not urban preference/abundance. We found that showing an association between song frequency and urban tolerance requires controlling for additional species traits that influence urban living. On the contrary, controlling for other species traits is not required to show a positive association between song frequency and use of noisy relative to quiet areas within the same type of environment. Together, comparative evidence indicates that masking by urban noise is part of a larger set of factors influencing urban living: all else being equal, species with high-frequency sounds are more likely to tolerate cities than species with low-frequency sounds, but they are not more likely to prefer, or to be more abundant in, urban than non-urban habitats. PMID:29515901

The comparative evidence for urban species sorting by anthropogenic noise.

PubMed

Cardoso, Gonçalo C; Hu, Yang; Francis, Clinton D

2018-02-01

Anthropogenic noise is more intense at lower sound frequencies, which could decrease urban tolerance of animals with low-frequency vocalizations. Four large comparative studies tested whether anthropogenic noise filters bird species according to the sound frequencies they use and produced discrepant results. We reanalysed data from these studies to explain their different results. Urban tolerance of bird species (defined here as often occurring and breeding in cities) is very weakly related to urban preference or relative abundance (defined based on changes in population density from urban to nearby rural environments). Data on urban preference/abundance are potentially accurate for individual cities but differ among cities for the same species, whereas existing data on urban tolerance are coarser but provide a more global synthesis. Cross-species comparisons find a positive association between the sound frequency of song and urban tolerance, but not urban preference/abundance. We found that showing an association between song frequency and urban tolerance requires controlling for additional species traits that influence urban living. On the contrary, controlling for other species traits is not required to show a positive association between song frequency and use of noisy relative to quiet areas within the same type of environment. Together, comparative evidence indicates that masking by urban noise is part of a larger set of factors influencing urban living: all else being equal, species with high-frequency sounds are more likely to tolerate cities than species with low-frequency sounds, but they are not more likely to prefer, or to be more abundant in, urban than non-urban habitats.

Influence of Urbanization on Body Size, Condition, and Physiology in an Urban Exploiter: A Multi-Component Approach

PubMed Central

Meillère, Alizée; Brischoux, François; Parenteau, Charline; Angelier, Frédéric

2015-01-01

Consistent expanding urbanization dramatically transforms natural habitats and exposes organisms to novel environmental challenges, often leading to reduced species richness and diversity in cities. However, it remains unclear how individuals are affected by the urban environment and how they can or cannot adjust to the specific characteristics of urban life (e.g. food availability). In this study, we used an integrative multi-component approach to investigate the effects of urbanization on the nutritional status of house sparrows (Passer domesticus). We assessed several morphological and physiological indices of body condition in both juveniles (early post-fledging) and breeding adults from four sites with different levels of urbanization in France, Western Europe. We found that sparrows in more urbanized habitats have reduced body size and body mass compared to their rural conspecifics. However, we did not find any consistent differences in a number of complementary indices of condition (scaled mass index, muscle score, hematocrit, baseline and stress-induced corticosterone levels) between urban and rural birds, indicating that urban sparrows may not be suffering nutritional stress. Our results suggest that the urban environment is unlikely to energetically constrain adult sparrows, although other urban-related variables may constrain them. On the other hand, we found significant difference in juvenile fat scores, suggesting that food types provided to young sparrows differed highly between habitats. In addition to the observed smaller size of urban sparrows, these results suggest that the urban environment is inadequate to satisfy early-life sparrows’ nutritional requirements, growth, and development. The urban environment may therefore have life-long consequences for developing birds. PMID:26270531

Influence of Urbanization on Body Size, Condition, and Physiology in an Urban Exploiter: A Multi-Component Approach.

PubMed

Meillère, Alizée; Brischoux, François; Parenteau, Charline; Angelier, Frédéric

2015-01-01

Consistent expanding urbanization dramatically transforms natural habitats and exposes organisms to novel environmental challenges, often leading to reduced species richness and diversity in cities. However, it remains unclear how individuals are affected by the urban environment and how they can or cannot adjust to the specific characteristics of urban life (e.g. food availability). In this study, we used an integrative multi-component approach to investigate the effects of urbanization on the nutritional status of house sparrows (Passer domesticus). We assessed several morphological and physiological indices of body condition in both juveniles (early post-fledging) and breeding adults from four sites with different levels of urbanization in France, Western Europe. We found that sparrows in more urbanized habitats have reduced body size and body mass compared to their rural conspecifics. However, we did not find any consistent differences in a number of complementary indices of condition (scaled mass index, muscle score, hematocrit, baseline and stress-induced corticosterone levels) between urban and rural birds, indicating that urban sparrows may not be suffering nutritional stress. Our results suggest that the urban environment is unlikely to energetically constrain adult sparrows, although other urban-related variables may constrain them. On the other hand, we found significant difference in juvenile fat scores, suggesting that food types provided to young sparrows differed highly between habitats. In addition to the observed smaller size of urban sparrows, these results suggest that the urban environment is inadequate to satisfy early-life sparrows' nutritional requirements, growth, and development. The urban environment may therefore have life-long consequences for developing birds.

Assessing surface albedo change and its induced radiation budget under rapid urbanization with Landsat and GLASS data

NASA Astrophysics Data System (ADS)

Hu, Yonghong; Jia, Gensuo; Pohl, Christine; Zhang, Xiaoxuan; van Genderen, John

2016-02-01

Radiative forcing (RF) induced by land use (mainly surface albedo) change is still not well understood in climate change science, especially the effects of changes in urban albedo due to rapid urbanization on the urban radiation budget. In this study, a modified RF derivation approach based on Landsat images was used to quantify changes in the solar radiation budget induced by variations in surface albedo in Beijing from 2001 to 2009. Field radiation records from a Beijing meteorological station were used to identify changes in RF at the local level. There has been rapid urban expansion over the last decade, with the urban land area increasing at about 3.3 % annually from 2001 to 2009. This has modified three-dimensional urban surface properties, resulting in lower albedo due to complex building configurations of urban centers and higher albedo on flat surfaces of suburban areas and cropland. There was greater solar radiation (6.93 × 108 W) in the urban center in 2009 than in 2001. However, large cropland and urban fringe areas caused less solar radiation absorption. RF increased with distance from the urban center (less than 14 km) and with greater urbanization, with the greatest value being 0.41 W/m2. The solar radiation budget in urban areas was believed to be mainly influenced by urban structural changes in the horizontal and vertical directions. Overall, the results presented herein indicate that cumulative urbanization impacts on the natural radiation budget could evolve into an important driver of local climate change.

Recent urban policy and development in China: a reversal of "anti-urbanism".

PubMed

Kwok, R Y

1987-10-01

The nature of and reasons for China's urban distribution policy adopted in 1982 are examined. The influence of socialist planning ideology on urban policy is noted. Contradictions between economic reform and urban policies are identified.

A Technical Guide to Urban Community Forestry: Urban and Community Forestry: Improving Our Quality of Life

Treesearch

USDA Forest Service

1993-01-01

Trees growing within cities and towns form a forest-an urban forest. But urban trees require special attention, because they are expected to exist within the urban environment. With its infrastructure of streets, sidewalks, curbs, buried utilities, overhead power lines and buildings, the urban environment places tremendous stresses on trees. With proper care, trees...

Advising an Urban FFA Chapter: A Narrative of Two Urban FFA Advisors

ERIC Educational Resources Information Center

Martin, Michael J.; Kitchel, Tracy

2015-01-01

Advising an urban FFA chapter can be a challenge for urban agriculture teachers. The contextual differences between the rural-oriented FFA and urban FFA members can make bridging the gap difficult. This narrative study sought to explore how the urban context shapes the work of an FFA chapter from the perspectives of two FFA advisors at the same…

Urban forest biomass estimates: is it important to use allometric relationships developed specifically for urban trees? 

Treesearch

M.R. McHale; I.C. Burke; M.A. Lefsky; P.J. Peper; E.G. McPherson

2009-01-01

Many studies have analyzed the benefits, costs, and carbon storage capacity associated with urban trees. These studies have been limited by a lack of research on urban tree biomass, such that estimates of carbon storage in urban systems have relied upon allometric relationships developed in traditional forests. As urbanization increases globally, it is becoming...

Forestry in urban and urbanizing areas of the United States; connecting people with forest in the 21st century

Treesearch

John F. Dwyer; Gina M. Childs; David J. Nowak

2000-01-01

Resource managers worldwide face challenges in responding to expanding urbanization and its effects on forest resources. These challenges can be met head on if managers work toward: (1) comprehensive management of forest resources in urban and urbanizing areas, and (2)connection of urban people with forests and their management. Opportunities exist for...

Soil carbon pools and fluxes in urban ecosystems

Treesearch

R. Pouyat; P. Groffman; I Yesilonis; L. Hernandez

2002-01-01

The transformation of landscapes from non-urban to urban land use has the potential to greatly modify soil carbon (C) pools and fluxes. For urban ecosystems, very little data exists to assess whether urbanization leads to an increase or decrease in soil C pools. We analyzed three data sets to assess the potential for urbanization to affect soil organic C. These...

Urban Is Floating Face down in the Mainstream: Using Hip-Hop-Based Education Research to Resurrect "The Urban" in Urban Education

ERIC Educational Resources Information Center

Irby, Decoteau J.

2015-01-01

Throughout this article, I argue that within the mainstream field of urban education, "the urban" is floating face down, lifeless, and devoid of significant meaning. "City" and "urban" function as taken-for-granted variables that stand in the rightful place of rich explanations, based in theory and evidence, of the…

Extending large-scale forest inventories to assess urban forests.

PubMed

Corona, Piermaria; Agrimi, Mariagrazia; Baffetta, Federica; Barbati, Anna; Chiriacò, Maria Vincenza; Fattorini, Lorenzo; Pompei, Enrico; Valentini, Riccardo; Mattioli, Walter

2012-03-01

Urban areas are continuously expanding today, extending their influence on an increasingly large proportion of woods and trees located in or nearby urban and urbanizing areas, the so-called urban forests. Although these forests have the potential for significantly improving the quality the urban environment and the well-being of the urban population, data to quantify the extent and characteristics of urban forests are still lacking or fragmentary on a large scale. In this regard, an expansion of the domain of multipurpose forest inventories like National Forest Inventories (NFIs) towards urban forests would be required. To this end, it would be convenient to exploit the same sampling scheme applied in NFIs to assess the basic features of urban forests. This paper considers approximately unbiased estimators of abundance and coverage of urban forests, together with estimators of the corresponding variances, which can be achieved from the first phase of most large-scale forest inventories. A simulation study is carried out in order to check the performance of the considered estimators under various situations involving the spatial distribution of the urban forests over the study area. An application is worked out on the data from the Italian NFI.

Causes and Disparities in Death Rates Among Urban American Indian and Alaska Native Populations, 1999-2009.

PubMed

Jacobs-Wingo, Jasmine L; Espey, David K; Groom, Amy V; Phillips, Leslie E; Haverkamp, Donald S; Stanley, Sandte L

2016-05-01

To characterize the leading causes of death for the urban American Indian/Alaska Native (AI/AN) population and compare with urban White and rural AI/AN populations. We linked Indian Health Service patient registration records with the National Death Index to reduce racial misclassification in death certificate data. We calculated age-adjusted urban AI/AN death rates for the period 1999-2009 and compared those with corresponding urban White and rural AI/AN death rates. The top-5 leading causes of death among urban AI/AN persons were heart disease, cancer, unintentional injury, diabetes, and chronic liver disease and cirrhosis. Compared with urban White persons, urban AI/AN persons experienced significantly higher death rates for all top-5 leading causes. The largest disparities were for diabetes and chronic liver disease and cirrhosis. In general, urban and rural AI/AN persons had the same leading causes of death, although urban AI/AN persons had lower death rates for most conditions. Urban AI/AN persons experience significant disparities in death rates compared with their White counterparts. Public health and clinical interventions should target urban AI/AN persons to address behaviors and conditions contributing to health disparities.

[A review on the urban green space cooling effect based on field measurement of air temperature].

PubMed

Liu, Feng Feng; Yan, Wei Jiao; Kong, Fan Hua; Yin, Hai Wei; Ban, Yu Long; Xu, Wen Bin

2017-04-18

With the development of urbanization, the effect of urban heat island has become increasingly evident. As an essential component of the urban natural landscapes, urban green space plays an important role in mitigating the effect of urban heat island. However, facing the rapid urbanization and changing environment, how to rationally plan and design the green space and realize its best cooling effect which can improve the urban environment and microclimate is still an urgent problem to be solved. So there is a strong need for mulitiscale researches on the cooling effect of urban green space. This paper systematically gave a review on the cooling effect of urban green space based on field measurement of air temperature, the main factors that influenced the cooling effect of green space were explored from three aspects including the area and shape characteristics of urban green space, the structure characteristics of vegetation and the external factors which affected the cooling effect, and the characteristics of the cooling effect of the green space were summarized from the aspect of time variation and distance decay. Then, the main problems and future research prospects of urban green space cooling effect were put forward.

Assessment of urban sustainability efficiency based on general data envelopment analysis: a case study of two cities in western and eastern China.

PubMed

Yan, Yan; Shan, Peng; Wang, Chenxing; Quan, Yuan; Wu, Di; Zhao, Chunli; Wu, Gang; Deng, Hongbing

2017-04-01

Sustainable urban development focuses on enhancing urban well-being, while also balancing the demands of urban social and economic development, natural resource consumption, and environmental pollution. This work used general data envelopment analysis to assess the urban sustainability efficiency (USE) and sustainability potential (SP) in Lanzhou and Xiamen, two cities that are characteristic of urban areas in western and eastern China. The assessment indicator system included important natural and urban welfare factors as input and output indices, respectively. The results showed that overall urban sustainability efficiency increased in Lanzhou and Xiamen from 1985 to 2010, but that the sustainability of natural resources clearly decreased. The urban sustainability efficiency of Xiamen was higher than that of Lanzhou, and the sustainability potential of Xiamen was lower than that of Lanzhou; this indicates that Xiamen performed better in terms of urban sustainable development. The urban sustainability efficiency in Xiamen has increased with increasing urban population, and the rate and scale of economic development have been higher than in Lanzhou. The assessment and analysis performed in this study show that cities with different natural resources and development characteristics have different forms, patterns, and trajectories of sustainable development.

Impacts of urban landscape patterns on urban thermal variations in Guangzhou, China

NASA Astrophysics Data System (ADS)

Chen, Youjun; Yu, Shixiao

2017-02-01

One of the key impacts of rapid urbanization on the environment is the effect of surface urban thermal variations (SUTV). Understanding the effects of urban landscape features on SUTV is crucial for improving the ecology and sustainability of cities. In this study, an investigation was conducted to detect urban landscape patterns and assess their impact on surface temperature. Landsat images: Thematic Mapper was used to calculate land surface temperature (LST) in Guangzhou, the capital city of Guangdong Province in southern China. SUTV zones, including surface urban heat islands (SUHI) and surface urban heat sinks (SUHS), were then empirically identified. The composition and configuration of landscape patterns were measured by a series of spatial metrics at the class and landscape levels in the SUHI and SUHS zones. How both landscape composition and configuration influence urban thermal characteristics was then analysed. It was found that landscape composition has the strongest effect on SUTV, but that urban landscape configuration also influences SUTV. These findings are helpful for achieving a comprehensive understanding of how urban landscape patterns impact SUTV and can help in the design of effective urban landscape patterns to minimize the effects of SUHI.

The NSF-RCN Urban Heat Island Network

NASA Astrophysics Data System (ADS)

Snyder, P. K.; Twine, T. E.; Hamilton, P.; Shepherd, M.; Stone, B., Jr.

2016-12-01

In much of the world cities are warming at twice the rate of outlying rural areas. The frequency of urban heat waves is projected to increase with climate change through the 21st century. Addressing the economic, environmental, and human costs of urban heat islands requires a better understanding of their behavior from many disciplinary perspectives. The goal of this four-year Urban Heat Island Network is to (1) bring together scientists studying the causes and impacts of urban warming, (2) advance multidisciplinary understanding of urban heat islands, (3) examine how they can be ameliorated through engineering and design practices, and (4) share these new insights with a wide array of stakeholders responsible for managing urban warming to reduce their health, economic, and environmental impacts. The NSF-RCN Urban Heat Island Network involves atmospheric scientists, engineers, architects, landscape designers, urban planners, public health experts, and education and outreach experts, who will share knowledge, evaluate research directions, and communicate knowledge and research recommendations to the larger research community as well as stakeholders engaged in developing strategies to adapt to and mitigate urban warming. The first Urban Climate Institute was held in Saint Paul, MN in July 2013 and focused on the characteristics of urban heat islands. Scientists engaged with local practitioners to improve communication pathways surrounding issues of understanding, adapting to, and mitigating urban warming. The second Urban Climate Institute was held in Atlanta, Georgia in July 2014 and focused on urban warming and public health. The third Urban Climate Institute was held in Athens, GA in July 2015 and focused on urban warming and the role of the built environment. Scientists and practitioners discussed strategies for mitigation and adaptation. The fourth Institute was held in Saint Paul, MN in July 2016 and focused on putting research to practice. Evaluation experts at the Science Museum of Minnesota have extensively evaluated the Institutes to inform other research coordination networks and to identify effective ways that researchers and practitioners can share knowledge and communicate more effectively.

The NSF-RCN Urban Heat Island Network

NASA Astrophysics Data System (ADS)

Twine, T. E.; Snyder, P. K.; Hamilton, P.; Shepherd, M.; Stone, B., Jr.

2014-12-01

In much of the world cities are warming at twice the rate of outlying rural areas. The frequency of urban heat waves is projected to increase with climate change through the 21stcentury. Addressing the economic, environmental, and human costs of urban heat islands requires a better understanding of their behavior from many disciplinary perspectives. The goal of this four-year Urban Heat Island Network is to (1) bring together scientists studying the causes and impacts of urban warming, (2) advance multidisciplinary understanding of urban heat islands, (3) examine how they can be ameliorated through engineering and design practices, and (4) share these new insights with a wide array of stakeholders responsible for managing urban warming to reduce their health, economic, and environmental impacts. The Urban Heat Island Network involves atmospheric scientists, engineers, architects, landscape designers, urban planners, public health experts, and education and outreach experts, who will share knowledge, evaluate research directions, and communicate knowledge and research recommendations to the larger research community as well as stakeholders engaged in developing strategies to adapt to and mitigate urban warming. The first Urban Climate Institute was held in Saint Paul, Minnesota in July 2013 and focused on the characteristics of urban heat islands. Scientists engaged with local practitioners to improve communication pathways surrounding issues of understanding, adapting to, and mitigating urban warming. The second Urban Climate Institute was held in Atlanta, Georgia in July 2014 and focused on urban warming and public health. Scientists discussed the state of the science on urban modeling, heat adaptation, air pollution, and infectious disease. Practitioners informed participants on emergency response methods and protocols related to heat and other extreme weather events. Evaluation experts at the Science Museum of Minnesota have extensively evaluated both Institutes to improve future Institutes and to inform other research coordination networks. Two more Institutes are planned for 2015 and 2016 focusing on urban warming and the built environment, and education and outreach.

Effects of urban form on the urban heat island effect based on spatial regression model.

PubMed

Yin, Chaohui; Yuan, Man; Lu, Youpeng; Huang, Yaping; Liu, Yanfang

2018-09-01

The urban heat island (UHI) effect is becoming more of a concern with the accelerated process of urbanization. However, few studies have examined the effect of urban form on land surface temperature (LST) especially from an urban planning perspective. This paper used spatial regression model to investigate the effects of both land use composition and urban form on LST in Wuhan City, China, based on the regulatory planning management unit. Landsat ETM+ image data was used to estimate LST. Land use composition was calculated by impervious surface area proportion, vegetated area proportion, and water proportion, while urban form indicators included sky view factor (SVF), building density, and floor area ratio (FAR). We first tested for spatial autocorrelation of urban LST, which confirmed that a traditional regression method would be invalid. A spatial error model (SEM) was chosen because its parameters were better than a spatial lag model (SLM). The results showed that urban form metrics should be the focus for mitigation efforts of UHI effects. In addition, analysis of the relationship between urban form and UHI effect based on the regulatory planning management unit was helpful for promoting corresponding UHI effect mitigation rules in practice. Finally, the spatial regression model was recommended to be an appropriate method for dealing with problems related to the urban thermal environment. Results suggested that the impact of urbanization on the UHI effect can be mitigated not only by balancing various land use types, but also by optimizing urban form, which is even more effective. This research expands the scientific understanding of effects of urban form on UHI by explicitly analyzing indicators closely related to urban detailed planning at the level of regulatory planning management unit. In addition, it may provide important insights and effective regulation measures for urban planners to mitigate future UHI effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Urban inequities; urban rights: a conceptual analysis and review of impacts on children, and policies to address them.

PubMed

Stephens, Carolyn

2012-06-01

This paper explores current conceptual understanding of urban social, environmental, and health inequality and inequity, and looks at the impact of these processes on urban children and young people in the 21st century. This conceptual analysis was commissioned for a discussion paper for UNICEF's flagship publication: State of the World's Children 2012: Children in an Urban World. The aim of the paper is to examine evidence on the meaning of urban inequality and inequity for urban children and young people. It further looks at the controversial policies of targeting "vulnerable" young people, and policies to achieve the urban MDGs. Finally, the paper looks briefly at the potential of concepts such as environment justice and rights to change our understanding of urban inequality and inequity.

Urban plant physiology: adaptation-mitigation strategies under permanent stress.

PubMed

Calfapietra, Carlo; Peñuelas, Josep; Niinemets, Ülo

2015-02-01

Urban environments that are stressful for plant function and growth will become increasingly widespread in future. In this opinion article, we define the concept of 'urban plant physiology', which focuses on plant responses and long term adaptations to urban conditions and on the capacity of urban vegetation to mitigate environmental hazards in urbanized settings such as air and soil pollution. Use of appropriate control treatments would allow for studies in urban environments to be comparable to expensive manipulative experiments. In this opinion article, we propose to couple two approaches, based either on environmental gradients or manipulated gradients, to develop the concept of urban plant physiology for assessing how single or multiple environmental factors affect the key environmental services provided by urban forests. Copyright © 2014 Elsevier Ltd. All rights reserved.

Projected impact of urbanization on cardiovascular disease in China.

PubMed

Chan, Faye; Adamo, Susana; Coxson, Pamela; Goldman, Lee; Gu, Dongfeng; Zhao, Dong; Chen, Chung-Shiuan; He, Jiang; Mara, Valentina; Moran, Andrew

2012-10-01

The Coronary Heart Disease (CHD) Policy Model-China, a national scale cardiovascular disease computer simulation model, was used to project future impact of urbanization. Populations and cardiovascular disease incidence rates were stratified into four submodels: North-Urban, South-Urban, North-Rural, and South-Rural. 2010 was the base year, and high and low urbanization rate scenarios were used to project 2030 populations. Rural-to-urban migration, population growth, and aging were projected to more than double cardiovascular disease events in urban areas and increase events by 27.0-45.6% in rural areas. Urbanization is estimated to raise age-standardized coronary heart disease incidence by 73-81 per 100,000 and stroke incidence only slightly. Rural-to-urban migration will likely be a major demographic driver of the cardiovascular disease epidemic in China.

Longwave infrared observation of urban landscapes

NASA Technical Reports Server (NTRS)

Goward, S. N.

1981-01-01

An investigation is conducted regarding the feasibility to develop improved methods for the identification and analysis of urban landscapes on the basis of a utilization of longwave infrared observations. Attention is given to landscape thermal behavior, urban thermal properties, modeled thermal behavior of pavements and buildings, and observed urban landscape thermal emissions. The differential thermal behavior of buildings, pavements, and natural areas within urban landscapes is found to suggest that integrated multispectral solar radiant reflectance and terrestrial radiant emissions data will significantly increase potentials for analyzing urban landscapes. In particular, daytime satellite observations of the considered type should permit better identification of urban areas and an analysis of the density of buildings and pavements within urban areas. This capability should enhance the utility of satellite remote sensor data in urban applications.

Parental encouragement of initiative-taking and adjustment in Chinese children from rural, urban, and urbanized families.

PubMed

Chen, Xinyin; Li, Dan

2012-12-01

Due to the requirements of the competitive, market-oriented urban society, parents in urban and urbanized families are more likely than parents in rural families to encourage initiative-taking in child rearing in China. The socialization experiences of children from different types of families may be related to their adjustment. This study examined parental socialization attitudes, social and school adjustment, and their relations in Chinese children from rural, urban, and urbanized families. Participants were elementary school students (N = 1,033; M age = 11 years) and their parents in China. Data were obtained from parental reports, peer evaluations, teacher ratings, and school records. A multivariate analysis of variance revealed that parents in urban and urbanized families had higher scores than parents in rural families on encouragement of initiative-taking. Urban children, particularly girls, were more sociable, obtained higher social status, and had fewer school problems than their rural counterparts. Children from urbanized families were different from rural children and similar to urban children in social and school adjustment. Moreover, multigroup invariance tests showed that parental encouragement of initiative-taking was associated more strongly with children's sociable-assertive behavior and social standing in the urban and urbanized groups than in the rural group. The results indicate that particular socialization attitudes may vary in their adaptive value in child development as a function of specific social and cultural requirements in changing societies. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Estimating changes in urban land and urban population using refined areal interpolation techniques

NASA Astrophysics Data System (ADS)

Zoraghein, Hamidreza; Leyk, Stefan

2018-05-01

The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead, it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.

Changing Urbania: Estimating Changes in Urban Land and Urban Population Using Refined Areal Interpolation Techniques

NASA Astrophysics Data System (ADS)

Zoraghein, H.; Leyk, S.; Balk, D.

2017-12-01

The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. The U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.

Toward a research and action agenda on urban planning/design and health equity in cities in low and middle-income countries.

PubMed

Smit, Warren; Hancock, Trevor; Kumaresen, Jacob; Santos-Burgoa, Carlos; Sánchez-Kobashi Meneses, Raúl; Friel, Sharon

2011-10-01

The importance of reestablishing the link between urban planning and public health has been recognized in recent decades; this paper focuses on the relationship between urban planning/design and health equity, especially in cities in low and middle-income countries (LMICs). The physical urban environment can be shaped through various planning and design processes including urban planning, urban design, landscape architecture, infrastructure design, architecture, and transport planning. The resultant urban environment has important impacts on the health of the people who live and work there. Urban planning and design processes can also affect health equity through shaping the extent to which the physical urban environments of different parts of cities facilitate the availability of adequate housing and basic infrastructure, equitable access to the other benefits of urban life, a safe living environment, a healthy natural environment, food security and healthy nutrition, and an urban environment conducive to outdoor physical activity. A new research and action agenda for the urban environment and health equity in LMICs should consist of four main components. We need to better understand intra-urban health inequities in LMICs; we need to better understand how changes in the built environment in LMICs affect health equity; we need to explore ways of successfully planning, designing, and implementing improved health/health equity; and we need to develop evidence-based recommendations for healthy urban planning/design in LMICs.

Microgeographic differentiation in thermal performance curves between rural and urban populations of an aquatic insect.

PubMed

Tüzün, Nedim; Op de Beeck, Lin; Brans, Kristien I; Janssens, Lizanne; Stoks, Robby

2017-12-01

The rapidly increasing rate of urbanization has a major impact on the ecology and evolution of species. While increased temperatures are a key aspect of urbanization ("urban heat islands"), we have very limited knowledge whether this generates differentiation in thermal responses between rural and urban populations. In a common garden experiment, we compared the thermal performance curves (TPCs) for growth rate and mortality in larvae of the damselfly Coenagrion puella from three urban and three rural populations. TPCs for growth rate shifted vertically, consistent with the faster-slower theoretical model whereby the cold-adapted rural larvae grew faster than the warm-adapted urban larvae across temperatures. In line with costs of rapid growth, rural larvae showed lower survival than urban larvae across temperatures. The relatively lower temperatures hence expected shorter growing seasons in rural populations compared to the populations in the urban heat islands likely impose stronger time constraints to reach a certain developmental stage before winter, thereby selecting for faster growth rates. In addition, higher predation rates at higher temperature may have contributed to the growth rate differences between urban and rural ponds. A faster-slower differentiation in TPCs may be a widespread pattern along the urbanization gradient. The observed microgeographic differentiation in TPCs supports the view that urbanization may drive life-history evolution. Moreover, because of the urban heat island effect, urban environments have the potential to aid in developing predictions on the impact of climate change on rural populations.

Nested High Resolution Modeling of the Impact of Urbanization on Regional Climate in Three Vast Urban Agglomerations in China

NASA Astrophysics Data System (ADS)

Wang, Jun; Feng, Jinming; Yan, Zhongwei; Hu, Yonghong; Jia, Gensuo

2013-04-01

In this paper, the Weather Research and Forecasting (WRF) model coupled to the Urban Canopy Model (UCM) is employed to simulate the impact of urbanization on the regional climate over three vast city agglomerations in China. Based on high resolution land use and land cover data, two scenarios are designed to represent the non-urban and current urban land use distributions. By comparing the results of two nested, high resolution numerical experiments, the spatial and temporal changes on surface air temperature, heat stress index, surface energy budget and precipitation due to urbanization are analyzed and quantified. Urban expansion increases the surface air temperature in urban areas by about 1? and this climatic forcing of urbanization on temperature is more pronounced in summer and nighttime than other seasons and daytime. The heat stress intensity, which reflects the combined effects of temperature and humidity, is enhanced by about 0.5 units in urban areas. The regional incoming solar radiation increases after urban expansion, which may be caused by the reduction of cloud fraction. The increased temperature and roughness of the urban surface lead to enhanced convergence. Meanwhile, the planetary boundary layer is deepened and water vapor is mixed more evenly in the lower atmosphere. The deficit of water vapor leads to less convective available potential energy and more convective inhibition energy. Finally, these combined effects may reduce the rainfall amount over urban area mainly in summer and change the regional precipitation pattern to a certain extent.

Measuring urban tree loss dynamics across residential landscapes

EPA Science Inventory

The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management. Urban trees are removed due to hazard prevention or aesthetic preferences. Previous research attributed tree loss t...

Exploring Relationships between North American Urban Form and Rates of Urban CO2 Emissions: A System Dynamics Approach

NASA Astrophysics Data System (ADS)

Emmi, P. C.; Forster, C. B.; Mills, J. I.; Call, B. D.; Sabula, J.; Klewicki, J. C.; Pataki, D. E.; Peterson, T. R.

2004-12-01

Cities are the locus of North America's most intense consumption of fossil fuels. Thus the rate and character of urbanization influence the rate of urban CO2 released into the global atmosphere. The rate of rural-to-urban land conversion, and changes in the population density of urban land, are influenced by coupled changes in urban demographics and the local economy. Urban sprawl (a rapid expansion of urban land with low population densities) is governed by a self-reinforcing feedback effect between urban transportation infrastructure investments (road building) and urban land development where road building begets new urban neighborhoods that, in turn, induce more road building that begets additional new neighborhoods. If unrestrained, this feedback effect leads to the unrestrained expansion of urban sprawl, urban vehicular travel and traffic congestion. This self-reinforcing feedback loop forms a key dynamic that controls the rate at which CO2-emitting fossil fuels are burned for transportation, electricity production, heating, and commercial/industrial processes. In a rapidly sprawling city residents must travel increasingly greater distances between work, shopping, and home while commercial service vehicles must travel to increasingly remote residential locations. The increasing number of vehicle trips and vehicle miles traveled, combined with the growing prevalence of ever-lower density urban land development, leads to a rapid increase in mobile and stationary CO2 emissions. A more compact and punctuated form of urban development with higher-density and mixed-use urban activity centers leads to reduced CO2 emissions. Those who shape urban development policy are often unconcerned by increasing CO2 emissions unless they can be linked to: (1) local concerns about criteria air pollutant emissions and air quality, (2) the dependency of federal infrastructure funding on meeting ambient air quality standards, and (3) the consequences of human exposure to health risks associated with declining air quality. The dynamic simulation of urban systems demonstrates that a suite of policies can be found to diminish sprawl and defeat traffic congestion thereby safeguarding the vitality a city. A systems thinking approach, facilitated by a community engagement process, has further enabled community opinion leaders and policy makers to map the key features, linkages and feedbacks of a complex, CO2-emitting urban ecosystem. A corresponding lumped-parameter, simulation model provides a framework for decision makers and stakeholders to explore the consequences of alternative options for managing urban growth, sprawl and congestion while also reducing CO2 emissions.

Spatial temporal analysis of urban heat hazard in Tangerang City

NASA Astrophysics Data System (ADS)

Wibowo, Adi; Kuswantoro; Ardiansyah; Rustanto, Andry; Putut Ash Shidiq, Iqbal

2016-11-01

Urban heat is a natural phenomenon which might caused by human activities. The human activities were represented by various types of land-use such as urban and non-urban area. The aim of this study is to identify the urban heat behavior in Tangerang City as it might threats the urban environment. This study used three types of remote sensing data namely, Landsat TM, Landsat ETM+ and Landsat OLI-TIRS, to capture the urban heat behavior and to analysis the urban heat signature of Tangerang City in 2001, 2012, 2013, 2014, 2015 and 2016. The result showed that urban heat signature change dynamically each month based on the sun radiation. The urban heat island covered only small part of Tangerang City in 2001, but it was significantly increased and reached 50% of the area in 2012. Based on the result on urban heat signature, the threshold for threatening condition is 30 oC which recognized from land surface temperature (LST). The effective temperature (ET) index explains that condition as warm, uncomfortable, increase stress due to sweating and blood flow and may causing cardiovascular disorder.

Modelling the urban water cycle as an integrated part of the city: a review.

PubMed

Urich, Christian; Rauch, Wolfgang

2014-01-01

In contrast to common perceptions, the urban water infrastructure system is a complex and dynamic system that is constantly evolving and adapting to changes in the urban environment, to sustain existing services and provide additional ones. Instead of simplifying urban water infrastructure to a static system that is decoupled from its urban context, new management strategies use the complexity of the system to their advantage by integrating centralised with decentralised solutions and explicitly embedding water systems into their urban form. However, to understand and test possible adaptation strategies, urban water modelling tools are required to support exploration of their effectiveness as the human-technology-environment system coevolves under different future scenarios. The urban water modelling community has taken first steps to developing these new modelling tools. This paper critically reviews the historical development of urban water modelling tools and provides a summary of the current state of integrated modelling approaches. It reflects on the challenges that arise through the current practice of coupling urban water management tools with urban development models and discusses a potential pathway towards a new generation of modelling tools.

Advances on interdisciplinary approaches to urban carbon

NASA Astrophysics Data System (ADS)

Romero-Lankao, P.

2015-12-01

North American urban areas are emerging as climate policy and technology innovators, urbanization process laboratories, fonts of carbon relevant experiments, hubs for grass-roots mobilization, and centers for civil-society experiments to curb carbon emissions and avoid widespread and irreversible climate impacts. Since SOCCR diverse lines of inquiry on urbanization, urban areas and the carbon cycle have advanced our understanding of some of the societal processes through which energy and land uses affect carbon. This presentation provides an overview of these diverse perspectives. It suggests the need for approaches that complement and combine the plethora of existing insights into interdisciplinary explorations of how different urbanization processes, and socio-ecological and technological components of urban areas affect the spatial and temporal patterns of carbon emissions, differentially over time and within and across cities. It also calls for a more holistic approach to examining the carbon implications of urbanization and urban areas as places, based not only on demographics or income, but also on such other interconnected features of urban development pathways as urban form, economic function, economic growth policies and climate policies.

Improved Gradation for Rain Garden of Low Impact Development

NASA Astrophysics Data System (ADS)

Lee, Sandra; Chang, Fu-Ming

2016-04-01

With rapid urban and economic development, living standard improves in urban areas but urban ecological environments deteriorate rapidly. Urban waterlogging and flooding have become a serious problem for urban water security. As urbanization continues, sustainability is the key to balance between urban development and healthy environment. Rain garden is recommended to be one of the best ways to reduce urban pollutants. It not only diminishes runoff flooding but also purify water in the urban area. The studies on rain gardens are mainly about how to incorporate rain garden to purify water quality, but lack of researches on runoff control. This project focuses on rain garden under Low Impact Development using indoor laboratory to test and quantify the water holding capacities of two different Taiwan indigenous rain garden plants, Taiwan Cyclosorus and Sour Grass. The results show that the water holding capacity of Sour Grass (10%-37%) is better than that of Taiwan Cyclosorus (6.8%-17.3%). The results could be a helpful reference for Low Impact Development in urban flood prevention and urban planning. Keywords: Low Impact Development; rain garden; indoor laboratory experiments; water holding capacity; porosity

[Spatial tendency of urban land use in new Yinzhou Town of Ningbo City, Zhejiang Province of East China].

PubMed

Jiang, Wen-Wei; Guo, Hui-Hui; Mei, Yan-Xia

2012-03-01

By adopting gradient analysis combining with the analysis of urban land use degree, this paper studied the spatial layout characteristics of residential and industrial lands in new Yinzhou Town, and explored the location characters of various urban land use by selecting public green land, public facilities, and road as the location advantage factors. Gradient analysis could effectively connect with the spatial layout of urban land use, and quantitatively depict the spatial character of urban land use. In the new town, there was a new urban spatial center mostly within the radius of 2 km, namely, the urban core area had obvious location advantage in the cross-shaft direction urban development. On the south of Yinzhou Avenue, the urban hinterland would be constructed soon. In the future land use of the new town, the focus would be the reasonable vicissitude of industrial land after the adjustment of industrial structure, the high-efficient intensive use of the commercial land restricted by the compulsive condition of urban core area, and the agricultural land protection in the southeastern urban-rural fringe.

Urbanization in a great plains river: Effects on fishes and food webs

USGS Publications Warehouse

Eitzmann, J.L.; Paukert, C.P.

2010-01-01

Spatial variation of habitat and food web structure of the fish community was investigated at three reaches in the Kansas River, USA to determine if ??13C variability and ??15N values differ longitudinally and are related to urbanization and instream habitat. Fish and macroinvertebrates were collected at three river reaches in the Kansas River classified as the less urbanized reach (no urban in riparian zone; 40% grass islands and sand bars, braided channel), intermediate (14% riparian zone as urban; 22% grass islands and sand bars) and urbanized (59% of riparian zone as urban; 6% grass islands and sand bars, highly channelized) reaches in June 2006. The less urbanized reach had higher variability in ??13C than the intermediate and urbanized reaches, suggesting fish from these reaches utilized a variety of carbon sources. The ??15N also indicated that omnivorous and detritivorous fish species tended to consume prey at higher trophic levels in the less urbanized reach. Channelization and reduction of habitat related to urbanization may be linked to homogenization of instream habitat, which was related to river food webs. ?? 2009.

Study for urbanization corresponding to socio-economic activities in Savannaket, Laos using satellite remote sensing

NASA Astrophysics Data System (ADS)

Kimijiama, S.; Nagai, M.

2014-06-01

In Greater Mekong Sub-region (GMS), economic liberalization and deregulation facilitated by GMS Regional Economic Corporation Program (GMS-ECP) has triggered urbanization in the region. However, the urbanization rate and its linkage to socio-economic activities are ambiguous. The objectives of this paper are to: (a) determine the changes in urban area from 1972 to 2013 using remote sensing data, and (b) analyse the relationships between urbanization with respect to socio-economic activities in central Laos. The study employed supervised classification and human visible interpretation to determine changes in urbanization rate. Regression analysis was used to analyze the correlation between the urbanization rate and socio-economic variables. The result shows that the urban area increased significantly from 1972 to 2013. The socio-economic variables such as school enrollment, labour force, mortality rate, water source and sanitation highly correlated with the rate of urbanization during the period. The study concluded that identifying the highly correlated socio-economic variables with urbanization rate could enable us to conduct a further urbanization simulation. The simulation helps in designing policies for sustainable development.

Climate regulation services by urban lakes in Bucharest city

NASA Astrophysics Data System (ADS)

Ioja, Cristian; Cheval, Sorin; Vanau, Gabriel; Sandric, Ionut; Onose, Diana; Carstea, Elfrida

2017-04-01

Urban ecosystems services assessment is an important challenge for practitioners, due to the high complexity of relations between urban systems components, high vulnerability to climate change, and consequences in social-economical systems. Urban lakes represent a significant component in more European cities (average 5% of total surface). Adequate urban management supports diverse benefits of urban lakes: clean water availability, mediation of waste, toxics and other nuisance, air quality and climate regulation, support for physical, intelectual or spiritual interactions. Due to underestimation of climate change and misfit urban planning decision, these benefits may be lost or chaged into diservices. The aim of the paper is to assess the changes in terms of the urban lakes contribution role to regulate urban climate, using the Bucharest as case study. Using sensors and Modis, Sentinel and Landsat images, the paper experiments the evolution of climate regulation services of urban lakes under the pressure of urbanisation and climate change between 2008 and 2015. Urban lakes management has to include specific measures in order to help the cities to become more sustainable, resilient, liveable and healthly.

The new urban politics as a politics of carbon control.

PubMed

Jonas, Andrew E G; Gibbs, David; While, Aidan

2011-01-01

The new urban politics (NUP) literature has helped to draw attention to a new generation of entrepreneurial urban regimes involved in the competition to attract investment to cities. Interurban competition often had negative environmental consequences for the urban living place. Yet knowledge of the environment was not very central to understanding the NUP. Entrepreneurial urban regimes today are struggling to deal with climate change and reductions in greenhouse gas emissions. Carbon reduction strategies could have profound implications for interurban competition and the politics of urban development. This paper explores the rise of a distinctive low-carbon urban polity—carbon control—and examines its potential ramifications for a new environmental politics of urban development (NEPUD). The NEPUD signals the growing centrality of carbon control in discourses, strategies and struggles around urban development. Using examples from cities in the US and Europe, the paper examines how these new environmental policy considerations are being mainstreamed in urban development politics. Alongside competitiveness, the management of carbon emissions represents a new yet at the same time contestable mode of calculation in urban governance.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nugent, Philip J; Omitaomu, Olufemi A; Parish, Esther S

The urban climate is changing rapidly. Therefore, climate change and its projected impacts on environmental conditions must be considered in assessing and comparing urban planning alternatives. In this paper, we present an integrated framework for urban climate adaptation tool (Urban-CAT) that will help cities to plan for, rather than react to, possible risks. Urban-CAT will be developed as a scenario planning tool that is locally relevant to existing urban decision-making processes.

Urban Children in Distress: An Introduction to the Issues. Innocenti Occasional Papers. The Urban Child Series, Number 2.

ERIC Educational Resources Information Center

Blanc, Cristina S.

This publication presents a discussion of the status of poor urban children world-wide and the design of a five-nation study of the condition of distressed urban children. Following an introduction, Section 2 describes the urban child project designed to study and advance the plight of urban children in developing nations. Section 3 outlines the…

African urbanization in metropolitan South Africa--differential urbanization perspectives.

PubMed

Geyer, H S

1993-07-01

"As a potentially important urban development policy consideration, attention is focused in this paper on differential urbanization trends in South Africa at the metropolitan level. Recent informal urban settlement patterns of the African population within the major metropolitan areas are contrasted against these differential urbanization trends to determine the implications of both for residential development in the metropolitan areas during the post-apartheid era." excerpt

Sustaining America's urban trees and forests: a Forests on the Edge report

Treesearch

David J. Nowak; Paula B. Randler; Eric J. Greenfield; Sara J. Comas; Mary A. Carr; Ralph J. Alig

2010-01-01

Close to 80 percent of the U.S. population lives in urban areas and depends on the essential ecological, economic, and social benefits provided by urban trees and forests. However, the distribution of urban tree cover and the benefits of urban forests vary across the United States, as do the challenges of sustaining this important resource. As urban areas expand...

Removal of Ozone by Urban and Peri-Urban Forests: Evidence from Laboratory, Field, and Modeling Approaches.

PubMed

Calfapietra, Carlo; Morani, Arianna; Sgrigna, Gregorio; Di Giovanni, Sara; Muzzini, Valerio; Pallozzi, Emanuele; Guidolotti, Gabriele; Nowak, David; Fares, Silvano

2016-01-01

A crucial issue in urban environments is the interaction between urban trees and atmospheric pollution, particularly ozone (O). Ozone represents one of the most harmful pollutants in urban and peri-urban environments, especially in warm climates. Besides the large interest in reducing anthropogenic and biogenic precursors of O emissions, there is growing scientific activity aimed at understanding O removal by vegetation, particularly trees. The intent of this paper is to provide the state of the art and suggestions to improve future studies of O fluxes and to discuss implications of O flux studies to maximize environmental services through the planning and management of urban forests. To evaluate and quantify the potential of O removal in urban and peri-urban forests, we describe experimental approaches to measure O fluxes, distinguishing laboratory experiments, field measurements, and model estimates, including recent case studies. We discuss the strengths and weaknesses of the different approaches and conclude that the combination of the three levels of investigation is essential for estimating O removal by urban trees. We also comment on the implications of these findings for planning and management of urban forests, suggesting some key issues that should be considered to maximize O removal by urban and peri-urban forests. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Some structural aspects of urbanization in Ethiopia.

PubMed

Rafiq, M; Hailemariam, A

1987-07-01

This article studies the emerging patterns of urbanization in Ethiopia. Over the period from 1967-1984, a number of structural changes have occurred which are likely to play a dominant role in the future urban growth in Ethiopia. In spite of its long history of settled population, Ethiopia did not witness sustained growth of urban centers. Ethiopia is 1 of the least urbanized areas in the Third World. A 3rd aspect of urbanization in Ethiopia is the wide range of regional differentials in the level of urbanization. Most of the urban population is concentrated in 2 administrative regions--Shoa and Eritrea. A more balanced urban growth may, inter alia, involve a better spread in terms of higher education, industrialization, provision of health and social services, and the development of communication and commercial infrastructure. Another striking feature of urbanization in Ethiopia is that growth has not been disproportionately concentrated in the largest urban centers. The largest urban centers have not assumed an inordinately higher level of primacy. The basic form of the curve depicting the relationship between the size of a locality and its rank has remained unchanged over the period. The post-revolution land reforms and the new socioeconomic structure emerging from reorganization of the society appear to have a rural-urban migration inhibiting effect. Some of the country's regional differentials may be associated with environmental factors.

Urban weather data and building models for the inclusion of the urban heat island effect in building performance simulation.

PubMed

Palme, M; Inostroza, L; Villacreses, G; Lobato, A; Carrasco, C

2017-10-01

This data article presents files supporting calculation for urban heat island (UHI) inclusion in building performance simulation (BPS). Methodology is used in the research article "From urban climate to energy consumption. Enhancing building performance simulation by including the urban heat island effect" (Palme et al., 2017) [1]. In this research, a Geographical Information System (GIS) study is done in order to statistically represent the most important urban scenarios of four South-American cities (Guayaquil, Lima, Antofagasta and Valparaíso). Then, a Principal Component Analysis (PCA) is done to obtain reference Urban Tissues Categories (UTC) to be used in urban weather simulation. The urban weather files are generated by using the Urban Weather Generator (UWG) software (version 4.1 beta). Finally, BPS is run out with the Transient System Simulation (TRNSYS) software (version 17). In this data paper, four sets of data are presented: 1) PCA data (excel) to explain how to group different urban samples in representative UTC; 2) UWG data (text) to reproduce the Urban Weather Generation for the UTC used in the four cities (4 UTC in Lima, Guayaquil, Antofagasta and 5 UTC in Valparaíso); 3) weather data (text) with the resulting rural and urban weather; 4) BPS models (text) data containing the TRNSYS models (four building models).

Potential for use of environmental factors in urban planning

NASA Astrophysics Data System (ADS)

Teixeira da Silva, Ricardo; van der Ploeg, Martine; van Delden, Hedwig; Fleskens, Luuk

2016-04-01

Projections for population growth estimate, on top of the current 7.4 billion world population, an increase of 2 billion people for the next 40 years. It is also projected that 66 per cent of the world population in 2050 will live in urban areas. To accommodate the urban population growth cities are changing continuously land cover to urban areas. Such changes are a threat for natural resources and food production systems stability and capability to provide food and other functions. However, little has been done concerning a rational soil management for food production in urban and peri-urban areas. This study focuses on the assessment of soil lost due to urban expansion and discusses the potential loss regarding the quality of the soil for food production and environmental functions. It is relevant to increase the knowledge on the role of soils in peri-urban areas and in the interaction of physical, environmental and social factors. The methodology consists of assessing the soil quality in and around urban and peri-urban areas. It focuses particularly on the physical properties and the environmental factors, for two periods of time and account the potential losses due to urban expansion. This project is on-going, therefore current advances will be presented and will look for a discussion on the contribution of soil quality for decision-making and land management in urban and peri-urban areas.

[Evaluation on spatial structure and rationality of city parks based on goal of disaster prevention: An application of proximal area method in Changchun, China.

PubMed

Li, Xiao Ling; Xiu, Chun Liang; Cheng, Lin; Wang, Nyu Ying

2016-11-18

Urban shelter parks as one of the important urban elements are a main form of emergency shelters for a city. This study evaluated the spatial distribution of urban parks in Changchun City with the proximal area method based on disaster prevention goal. Results showed that the spatial distribution of urban shelter parks was unbalanced, with high concentration in the northwest and low concentration in the southeast. The spatial distribution of urban shelter parks of the same grade was concentrated, but the different grades were scattered. The validity of urban shelter parks was low. More than 50% of the park's per capita refuge area was insufficient. For nearly 40% of the parks, their accessibility was longer than the longest evacuation time. There were significant differences in effectiveness for urban parks of different grades. The urban shelter parks for central disaster prevention were the best, followed by the designated urban shelter parks, whereas urban shelter parks for emergency disaster prevention were the least effective. In view of the layout unreasonable situation of disaster prevention parks in Changchun City, we made following recommendations: the spatial distribution of nesting urban shelter parks with different grades should be used; standards set for urban shelter parks should evolve with population; and the construction of urban shelter parks for emergency disaster prevention should be strengthened.

[Prediction and simulation of urban area expansion in Pearl River Delta Region under the RCPs climate scenarios].

PubMed

Jiang, Oun-ou; Deng, Xiang-zheng; Ke, Xin-li; Zhao, Chun-hong; Zhang, Wei

2014-12-01

The sizes and number of cities in China are increasing rapidly and complicated changes of urban land use system have occurred as the social economy develops rapidly. This study took the urban agglomeration of Pearl River Delta Region as the study area to explore the driving mechanism of dynamic changes of urban area in the urbanization process under the joint influence of natural environment and social economic conditions. Then the CA (cellular automata) model was used to predict and simulate the urban area changes until 2030 under the designed scenarios of planning and RCPs (representative concentration pathways). The results indicated that urbanization was mainly driven by the non-agricultural population growth and social-economic development, and the transportation had played a fundamental role in the whole process, while the areas with high elevation or steep slope restricted the urbanization. Besides, the urban area would keep an expanding trend regardless of the scenarios, however, the expanding speed would slow down with different inflection points under different scenarios. The urban expansion speed increased in the sequence of the planning scenario, MESSAGE scenario and AIM scenario, and that under the MESSAGE climate scenario was more consistent with the current urban development trend. In addition, the urban expansion would mainly concentrate in regions with the relatively high urbanization level, e.g., Guangzhou, Dongguan, Foshan, Shenzhen, Zhanjiang and Chaoshan.

Investigating the vertical dimension of Singapore's urban heat island through quadcopter platforms: an pilot study

NASA Astrophysics Data System (ADS)

Chow, Winston; Ho, Dawn

2016-04-01

In numerous cities, measurements of urban warmth in most urban heat island (UHI) studies are generally constrained towards surface or near-surface (<2 m above surface level) levels across horizontal variations in land use and land cover. However, there has been hitherto limited attention towards the measurement of vertical temperature profiles extending from the urban surface, urban canopy layer through to the urban boundary layer. Knowledge of these profiles, through (a.) how they vary over different local urban morphologies, and (b.) develop with respect to synoptic meteorological conditions, are important towards several aspects of UHI research; these include validating modelling urban canopy lapse rate profiles or estimating the growth of urban plumes. In this novel study, we utilised temperature sensor-loggers attached onto remote controlled aerial quadcopter platforms to measure urban temperature profiles up to 100 m above ground level in Singapore, which is a rapidly urbanizing major tropical metropolis. Three different land use/land cover categories were sampled; a high-rise residential estate, a university campus, and an urban park/green-space. Sorties were flown repeatedly at four different times - sunrise, noon, sunset and midnight. Initial results indicate significant variations in intra-site stability and inversion development between the urban canopy and boundary layers. These profiles are also temporally dynamic, depending on the time of day and larger-scale weather conditions.

Can green roofs reduce urban heat stress in vulnerable urban communities: A coupled atmospheric and social modeling approach

NASA Astrophysics Data System (ADS)

Sharma, A.; Woodruff, S.; Budhathoki, M.; Hamlet, A. F.; Fernando, H. J. S.; Chen, F.

2017-12-01

Urban areas provide organized, engineered, sociological and economical infrastructure designed to provide a high quality of life, but the implementation and management of urban infrastructure has been a continued challenge. Increasing urbanization, warming climate, as well as anthropogenic heat emissions that accompany urban development generates "stress". This rapidly increasing `urban stress' affects the sustainability of cities, making populations more vulnerable to extreme hazards, such as heat. Cities are beginning to extensively use green roofs as a potential urban heat mitigation strategy. This study explores the potential of green roofs to reduce summertime temperatures in the most vulnerable neighborhoods of the Chicago metropolitan area by combining social vulnerability indices (a function of exposure, sensitivity and adaptive capacity), and temperatures from mesoscale model. Numerical simulations using urbanized version the Advanced Research Weather Research and Forecasting (WRF) model were performed to measure rooftop temperatures, a representative variable for exposure in this study. The WRF simulations were dynamically coupled with a green roof algorithm as a part of urban parameterization within WRF. Specifically, the study examines roof surface temperature with changing green roof fractions and how would they help reduce exposure to heat stress for vulnerable urban communities. This study shows an example of applied research that can directly benefit urban communities and be used by urban planners to evaluate mitigation strategies.

Understanding the health impacts of urbanization in China: A living laboratory for urban biogeochemistry research

NASA Astrophysics Data System (ADS)

Zhu, Y. G.

2015-12-01

China has the largest population in the world, and by 2011, more than 50% of its population are now living in cities. This ongoing societal change has profound impacts on environmental quality and population health. In addition to intensive discharges of waste, urbanization is not only changing the land use and land cover, but also inducing fundamental changes in biogeochemical processes. Unlike biogeochemistry in non-urban environment, the biological component of urban biogeochemistry is dominated by direct human activities, such as air pollution derived from transport, wastewater treatment, garbage disposal and increase in impervious surface etc. Managing urban biogeochemistry will include source control over waste discharge, eco-infrastructure (such as green space and eco-drainage), resource recovery from urban waste stream, and integration with peri-urban ecosystem, particularly with food production system. The overall goal of managing urban biogeochemistry is for human health and wellbeing, which is a global challenge. In this paper, the current status of urban biogeochemistry research in China will be briefly reviewed, and then it will focus on nutrient recycling and waste management, as these are the major driving forces of environmental quality changes in urban areas. This paper will take a holistic view on waste management, covering urban metabolism analysis, technological innovation and integration for resource recovery from urban waste stream, and risk management related to waste recycling and recovery.

COMPREHENSIVE PLAN FOR A SUSTAINABLE URBAN WATERSHED

EPA Science Inventory

Technical Challenge. This proposal deals with the urban watershed. The urban watershed is important to the quality of life in the city. For many urban dwellers, the urban stream represents a unique opportunity for recreation and the experience of the ...

Urban biomass - not an urban legend

USDA-ARS?s Scientific Manuscript database

Utilizing biomass from urban landscapes could significantly contribute to the nation’s renewable energy needs. There is an estimated 16.4 million hectares of land in urban areas cultivated with turfgrass and associated vegetation. Vegetation in urban areas is intensely managed which lead to regula...

Urbanization in Bangladesh: some contemporary observations.

PubMed

Laskar, S I

1996-01-01

The author analyzes "levels and trends of urbanization in Bangladesh. It also makes an attempt to elucidate the implications of urbanization.... The...analysis corroborates that although the overall level of urbanization remained low, the sheer magnitude of total urban population has become formidable." excerpt

Structural change in a system of urban places: the 20th-century evolution of Hungary's urban settlement network.

PubMed

Zovanyi, G

1986-02-01

A review of urban change in Hungary in the twentieth century is presented. Both the traditional approach to studying urban change, involving changes in the percentage of those residing in urban areas, and the newly developed approach, focusing on regional aspects of urbanization, are used in the analysis. "In sharp contrast to most European countries Hungary is shown to evidence continued centralization of urban development, but the recent experience of Budapest and other indicators are said to portend future decentralization." (summary in FRE, GER) excerpt

Effect of urbanization on population structure in U.A.R.

PubMed

Husein, H M; Sarhan, A E

1970-06-01

Census data from Egypt in 1927, 1937, 1947, and 1960 indicate slow urbanization through 1937 and more rapid urbanization thereafter. There is a higher proportion of working age (15-44) people in urban areas and a higher proportion of males. Both fertility and mortality rates are higher in rural than in urban areas, but the rate of overall population growth is greater in urban areas. Figures from 4 recently industrialized urban areas (El-Mahalla, Kafr el-Dawar, Helwan, and Aswan) bear out the conclusions drawn from the general census figures.

Urban bioclimatology.

PubMed

Mayer, H

1993-11-15

This article deals with the part of urban climatology which is of particular relevance to human beings. Presented first is a summary of all human biometerologically effective complexes, as well as other factors which are relevant to urban planning and which depend on atmospheric conditions in urban structures in a direct or indirect manner. Later, methods for human biometerologically significant assessment of thermal and air pollution components of the urban climate are discussed in detail, because these components can be strongly influenced by urban planning. The application of these methods is illustrated by some results of appropriate investigations in urban areas.

Disparities in Prevalence of Cardiometablic Risk Factors in Rural, Urban-Poor, and Urban-Middle Class Women in India.

PubMed

Mohan, Indu; Gupta, Rajeev; Misra, Anoop; Sharma, Krishna Kumar; Agrawal, Aachu; Vikram, Naval K; Sharma, Vinita; Shrivastava, Usha; Pandey, Ravindra M

2016-01-01

Urbanization is an important determinant of cardiovascular disease (CVD) risk. To determine location-based differences in CVD risk factors in India we performed studies among women in rural, urban-poor and urban middle-class locations. Population-based cross-sectional studies in rural, urban-poor, and urban-middle class women (35-70 y) were performed at multiple sites. We evaluated 6853 women (rural 2616, 5 sites; urban-poor 2008, 4 sites; urban middle-class 2229, 11 sites) for socioeconomic, lifestyle, anthropometric and biochemical risk factors. Descriptive statistics are reported. Mean levels of body mass index (BMI), waist circumference, waist-hip ratio (WHR), systolic BP, fasting glucose and cholesterol in rural, urban-poor and urban-middle class women showed significantly increasing trends (ANOVAtrend, p <0.001). Age-adjusted prevalence of diabetes and risk factors among rural, urban-poor and urban-middle class women, respectively was, diabetes (2.2, 9.3, 17.7%), overweight BMI ≥25 kg/m2 (22.5, 45.6, 57.4%), waist >80 cm (28.3, 63.4, 61.9%), waist >90 cm (8.4, 31.4, 38.2%), waist hip ratio (WHR) >0.8 (60.4, 90.7, 88.5), WHR>0.9 (13.0, 44.3, 56.1%), hypertension (31.6, 48.2, 59.0%) and hypercholesterolemia (13.5, 27.7, 37.4%) (Mantel Haenszel X2 ptrend <0.01). Inverse trend was observed for tobacco use (41.6, 19.6, 9.4%). There was significant association of hypertension, hypercholesterolemia and diabetes with overweight and obesity (adjusted R2 0.89-0.99). There are significant location based differences in cardiometabolic risk factors in India. The urban-middle class women have the highest risk compared to urban-poor and rural.

Disparities in Prevalence of Cardiometablic Risk Factors in Rural, Urban-Poor, and Urban-Middle Class Women in India

PubMed Central

Mohan, Indu; Gupta, Rajeev; Misra, Anoop; Sharma, Krishna Kumar; Agrawal, Aachu; Vikram, Naval K.; Sharma, Vinita; Shrivastava, Usha; Pandey, Ravindra M.

2016-01-01

Objective Urbanization is an important determinant of cardiovascular disease (CVD) risk. To determine location-based differences in CVD risk factors in India we performed studies among women in rural, urban-poor and urban middle-class locations. Methods Population-based cross-sectional studies in rural, urban-poor, and urban-middle class women (35–70y) were performed at multiple sites. We evaluated 6853 women (rural 2616, 5 sites; urban-poor 2008, 4 sites; urban middle-class 2229, 11 sites) for socioeconomic, lifestyle, anthropometric and biochemical risk factors. Descriptive statistics are reported. Results Mean levels of body mass index (BMI), waist circumference, waist-hip ratio (WHR), systolic BP, fasting glucose and cholesterol in rural, urban-poor and urban-middle class women showed significantly increasing trends (ANOVAtrend, p <0.001). Age-adjusted prevalence of diabetes and risk factors among rural, urban-poor and urban-middle class women, respectively was, diabetes (2.2, 9.3, 17.7%), overweight BMI ≥25 kg/m2 (22.5, 45.6, 57.4%), waist >80 cm (28.3, 63.4, 61.9%), waist >90 cm (8.4, 31.4, 38.2%), waist hip ratio (WHR) >0.8 (60.4, 90.7, 88.5), WHR>0.9 (13.0, 44.3, 56.1%), hypertension (31.6, 48.2, 59.0%) and hypercholesterolemia (13.5, 27.7, 37.4%) (Mantel Haenszel X2 ptrend <0.01). Inverse trend was observed for tobacco use (41.6, 19.6, 9.4%). There was significant association of hypertension, hypercholesterolemia and diabetes with overweight and obesity (adjusted R2 0.89–0.99). Conclusions There are significant location based differences in cardiometabolic risk factors in India. The urban-middle class women have the highest risk compared to urban-poor and rural. PMID:26881429

Interaction of childhood urbanicity and variation in dopamine genes alters adult prefrontal function as measured by functional magnetic resonance imaging (fMRI).

PubMed

Reed, Jessica L; D'Ambrosio, Enrico; Marenco, Stefano; Ursini, Gianluca; Zheutlin, Amanda B; Blasi, Giuseppe; Spencer, Barbara E; Romano, Raffaella; Hochheiser, Jesse; Reifman, Ann; Sturm, Justin; Berman, Karen F; Bertolino, Alessandro; Weinberger, Daniel R; Callicott, Joseph H

2018-01-01

Brain phenotypes showing environmental influence may help clarify unexplained associations between urban exposure and psychiatric risk. Heritable prefrontal fMRI activation during working memory (WM) is such a phenotype. We hypothesized that urban upbringing (childhood urbanicity) would alter this phenotype and interact with dopamine genes that regulate prefrontal function during WM. Further, dopamine has been hypothesized to mediate urban-associated factors like social stress. WM-related prefrontal function was tested for main effects of urbanicity, main effects of three dopamine genes-catechol-O-methyltransferase (COMT), dopamine receptor D1 (DRD1), and dopamine receptor D2 (DRD2)-and, importantly, dopamine gene-by-urbanicity interactions. For COMT, three independent human samples were recruited (total n = 487). We also studied 253 subjects genotyped for DRD1 and DRD2. 3T fMRI activation during the N-back WM task was the dependent variable, while childhood urbanicity, dopamine genotype, and urbanicity-dopamine interactions were independent variables. Main effects of dopamine genes and of urbanicity were found. Individuals raised in an urban environment showed altered prefrontal activation relative to those raised in rural or town settings. For each gene, dopamine genotype-by-urbanicity interactions were shown in prefrontal cortex-COMT replicated twice in two independent samples. An urban childhood upbringing altered prefrontal function and interacted with each gene to alter genotype-phenotype relationships. Gene-environment interactions between multiple dopamine genes and urban upbringing suggest that neural effects of developmental environmental exposure could mediate, at least partially, increased risk for psychiatric illness in urban environments via dopamine genes expressed into adulthood.

High urban population density of birds reflects their timing of urbanization.

PubMed

Møller, Anders Pape; Diaz, Mario; Flensted-Jensen, Einar; Grim, Tomas; Ibáñez-Álamo, Juan Diego; Jokimäki, Jukka; Mänd, Raivo; Markó, Gábor; Tryjanowski, Piotr

2012-11-01

Living organisms generally occur at the highest population density in the most suitable habitat. Therefore, invasion of and adaptation to novel habitats imply a gradual increase in population density, from that at or below what was found in the ancestral habitat to a density that may reach higher levels in the novel habitat following adaptation to that habitat. We tested this prediction of invasion biology by analyzing data on population density of breeding birds in their ancestral rural habitats and in matched nearby urban habitats that have been colonized recently across a continental latitudinal gradient. We estimated population density in the two types of habitats using extensive point census bird counts, and we obtained information on the year of urbanization when population density in urban habitats reached levels higher than that of the ancestral rural habitat from published records and estimates by experienced ornithologists. Both the difference in population density between urban and rural habitats and the year of urbanization were significantly repeatable when analyzing multiple populations of the same species across Europe. Population density was on average 30 % higher in urban than in rural habitats, although density reached as much as 100-fold higher in urban habitats in some species. Invasive urban bird species that colonized urban environments over a long period achieved the largest increases in population density compared to their ancestral rural habitats. This was independent of whether species were anciently or recently urbanized, providing a unique cross-validation of timing of urban invasions. These results suggest that successful invasion of urban habitats was associated with gradual adaptation to these habitats as shown by a significant increase in population density in urban habitats over time.

Exploring the Influence of Impervious Surface Density and Shape on Urban Heat Islands in the Northeast USA Using MODIS and Landsat

NASA Technical Reports Server (NTRS)

Zhang, Ping; Imhoff, Marc L.; Bounoua, Lahouri; Wolfe, Robert E.

2011-01-01

Impervious surface area (ISA) from the National Land Cover Database (NLCD) 2001 and land surface temperature (LST) from MODIS averaged over three annual cycles (2003-2005) are used in a spatial analysis to assess the urban heat island (UHI) signature and its relationship to settlement size and shape, development intensity distribution, and land cover composition for 42 urban settlements embedded in forest biomes in the Northeastern United States. Development intensity zones, based on percent ISA, are defined for each urban area emanating outward from the urban core to nearby rural areas and are used to stratify land surface temperature. The stratification is further constrained by biome type and elevation to insure objective intercomparisons between urban zones within an urban settlement and between settlements. Stratification based on ISA allows the definition of hierarchically ordered urban zones that are consistent across urban settlements and scales. In addition to the surrounding ecological context, we find that the settlement size and shape as well as the development intensity distribution significantly influence the amplitude of summer daytime UHI. Within the Northeastern US temperate broadleaf mixed forest, UHI magnitude is positively related to the logarithm of the urban area size. Our study indicates that for similar urban area sizes, the development intensity distribution is one of the major drivers of UHI. In addition to urban area size and development intensity distribution, this analysis shows that both the shape of the urban area and the land cover composition in the surrounding rural area play an important role in modulating the UHI magnitude in different urban settlements. Our results indicate that remotely sensed urban area size and shape as well as the development intensity distribution influence UHI amplitude across regional scales.

Comprehensive Evaluation of Urban Sprawl on Ecological Environment Using Multi-Source Data: a Case Study of Beijing

NASA Astrophysics Data System (ADS)

Wang, Hao; Ning, Xiaogang; Zhu, Weiwei; Li, Fei

2016-06-01

With urban population growing and urban sprawling, urban ecological environment problems appear. Study on spatiotemporal characteristics of urban sprawl and its impact on ecological environment is useful for ecological civilization construction. Although a lot of work has been conducted on urban sprawl and its impact on ecological environment, resolution of images to extract urban boundary was relatively coarse and most studies only focused on certain indicators of ecological environment, rather than comprehensive evaluation of urban ecological environmental impact. In this study, high-resolution remote sensing images of Beijing from aerial photography in 2002 and 2013 respectively are employed to extract urban boundary with manual interpretation. Fractional Vegetation Coverage (FVC), Water Density (WD), Impervious Surfaces Coverage (ISC), Net Primary Production (NPP), and Land Surface Temperature (LST) are adopted to represent ecological environment. The ecological environment indicators are measured with some general algorithms by combining Landsat images, GIS data and metrological data of 243 day, 2001 and 244 day, 2013. In order to evaluate the impact of urban sprawl on ecological environment, pseudo changes due to metrological variation and other noise in this time period are removed after images calibration. The impact of urban sprawl on ecological environment is evaluated at different scales of urban extent, Beijing ring road and watershed. Results show that Beijing had been undergoing a rapid urbanization from 2002 to 2013, with urban area increase from 600 square kilometres to 987 square kilometres. All ecological environment indicators except LST became terrible in urban sprawl region, with carbon reduction of approximate 40508 tons. The Beiyun River watershed of Beijing degraded seriously since ISC increased to 0.59. Gratifyingly, ecological environment indicators including NDVI, NPP, and LST inside of 4th Ring Road became well.

Addressing Inequities in Urban Health: Do Decision-Makers Have the Data They Need? Report from the Urban Health Data Special Session at International Conference on Urban Health Dhaka 2015.

PubMed

Elsey, H; Thomson, D R; Lin, R Y; Maharjan, U; Agarwal, S; Newell, J

2016-06-01

Rapid and uncontrolled urbanisation across low and middle-income countries is leading to ever expanding numbers of urban poor, defined here as slum dwellers and the homeless. It is estimated that 828 million people are currently living in slum conditions. If governments, donors and NGOs are to respond to these growing inequities they need data that adequately represents the needs of the urban poorest as well as others across the socio-economic spectrum.We report on the findings of a special session held at the International Conference on Urban Health, Dhaka 2015. We present an overview of the need for data on urban health for planning and allocating resources to address urban inequities. Such data needs to provide information on differences between urban and rural areas nationally, between and within urban communities. We discuss the limitations of data most commonly available to national and municipality level government, donor and NGO staff. In particular we assess, with reference to the WHO's Urban HEART tool, the challenges in the design of household surveys in understanding urban health inequities.We then present two novel approaches aimed at improving the information on the health of the urban poorest. The first uses gridded population sampling techniques within the design and implementation of household surveys and the second adapts Urban HEART into a participatory approach which enables slum residents to assess indicators whilst simultaneously planning the response. We argue that if progress is to be made towards inclusive, safe, resilient and sustainable cities, as articulated in Sustainable Development Goal 11, then understanding urban health inequities is a vital pre-requisite to an effective response by governments, donors, NGOs and communities.

Identifying urban infrastructure multi-hazard risk in developing country contexts

NASA Astrophysics Data System (ADS)

Taylor, Faith; Malamud, Bruce; Millington, James

2017-04-01

This work presents a method to coarsely zone urban areas into different infrastructure typologies, from which physical vulnerability to a range of natural hazards and multi-hazard interactions can be estimated, particularly for developing country contexts where access to data can be a challenge. This work builds upon techniques developed for urban micrometeorology for classifying 12 urban typologies (Stewart and Oke, 2011) using Landsat 8 30 m × 30 m remote sensing imagery (Betchel et al., 2015). For each of these 12 urban typologies, we develop general rules about the presence, type and level of service of 10 broad categories of infrastructure (including buildings, roads, electricity and water), which we refer to as 'urban textures'. We have developed and applied this technique to five urban areas varying in size and structure across Africa: Nairobi (Kenya); Karonga (Malawi); Mzuzu (Malawi); Ibadan (Nigeria) and Cape Town (South Africa). For each urban area, a training dataset of 10 samples of each of the 12 urban texture classes is digitised using Google Earth imagery. A random forest classification is performed using SAGA GIS, resulting in a map of different urban typologies for each city. Based on >1200 georeferenced field photographs and expert interviews for Karonga (Malawi) and Nairobi (Kenya), generally applicable rules about the presence, type and level of service of 12 infrastructure types (the 'urban texture') are developed for each urban typology. For each urban texture, we are broadly reviewing how each infrastructure might be physically impacted by 21 different natural hazards and hazard interactions. This can aid local stakeholders such as emergency responders and urban planners to systematically identify how the infrastructure in different parts of an urban area might be affected differently during a natural disaster event.

Response of vegetation phenology to urbanization in the conterminous United States

DOE PAGES

Li, Xuecao; Zhou, Yuyu; Asrar, Ghassem R.; ...

2016-12-18

The influence of urbanization on vegetation phenology is gaining considerable attention due to its implications for human health, cycling of carbon and other nutrients in Earth system. In this study, we examined the relationship between change in vegetation phenology and urban size, an indicator of urbanization, for the conterminous United States. We studied more than 4500 urban clusters of varying size to determine the impact of urbanization on plant phenology, with the aids of remotely sensed observations since 2003–2012. We found that phenology cycle (changes in vegetation greenness) in urban areas starts earlier (start of season, SOS) and ends latermore » (end of season, EOS), resulting in a longer growing season length (GSL), when compared to the respective surrounding urban areas. The average difference of GSL between urban and rural areas over all vegetation types, considered in this study, is about 9 days.Also, the extended GSL in urban area is consistent among different climate zones in the United States, whereas their magnitudes are varying across regions. We found that a tenfold increase in urban size could result in an earlier SOS of about 1.3 days and a later EOS of around 2.4 days. As a result, the GSL could be extended by approximately 3.6 days with a range of 1.6–6.5 days for 25th ~ 75th quantiles, with a median value of about 2.1 days. For different vegetation types, the phenology response to urbanization, as defined by GSL, ranges from 1 to 4 days. In conclusion, the quantitative relationship between phenology and urbanization is of great use for developing improved models of vegetation phenology dynamics under future urbanization, and for developing change indicators to assess the impacts of urbanization on vegetation phenology.« less

Challenges of urban planning in Palestine

NASA Astrophysics Data System (ADS)

Moghayer, Taher J. T.; Tesmamma Daget, Yidnekachew; Wang, Xingping

2017-08-01

For the last two centuries, Palestinian territory had faced several changes. This is due to historical precedents and the unstable political situation in the area. This has resulted in mutli-faced challenges in Palestine. The objective of this paper is to analyse and understand the major factors that had impacted the urban planning, urban form and urban development of the Palestinian territory. The findings showed that the lack of available land, rapid urban population growth, failure in urban planning policy decisions, the unstable political situation on the ground, fragmented urban developments in the west bank area, and also diffusion of urban sprawls within the landscapes and around the cities are the major factors that caused challenges in Palestine’s cities.

Urban Growth Scenarios of a Future MEGA City: Case Study Ahmedabad

NASA Astrophysics Data System (ADS)

Lehner, A.; Kraus, V.; Steinnocher, K.

2016-06-01

The study of urban areas and their development focuses on cities, their physical and demographic expansion and the tensions and impacts that go along with urban growth. Especially in developing countries and emerging national economies like India, consistent and up to date information or other planning relevant data all too often is not available. With its Smart Cities Mission, the Indian government places great importance on the future developments of Indian urban areas and pays tribute to the large-scale rural to urban migration. The potentials of urban remote sensing and its contribution to urban planning are discussed and related to the Indian Smart Cities Mission. A case study is presented showing urban remote sensing based information products for the city of Ahmedabad. Resulting urban growth scenarios are presented, hotspots identified and future action alternatives proposed.

Hormones in the city: endocrine ecology of urban birds.

PubMed

Bonier, Frances

2012-05-01

Urbanization dramatically changes the landscape, presenting organisms with novel challenges and often leading to reduced species diversity. Urban ecologists have documented numerous biotic and abiotic consequences of urbanization, such as altered climate, species interactions, and community composition, but we lack an understanding of the mechanisms underlying organisms' responses to urbanization. Here, I review findings from the nascent field of study of the endocrine ecology of urban birds. Thus far, no clear or consistent patterns have been revealed, but we do have evidence that urban habitat can shape endocrine traits, and that those traits might contribute to adaptation to the urban environment. I suggest strong approaches for future work addressing exciting questions about the role of endocrine traits in mediating responses to urbanization within species across the globe. Copyright © 2012 Elsevier Inc. All rights reserved.

Urban-area extraction from polarimetric SAR image using combination of target decomposition and orientation angle

NASA Astrophysics Data System (ADS)

Zou, Bin; Lu, Da; Wu, Zhilu; Qiao, Zhijun G.

2016-05-01

The results of model-based target decomposition are the main features used to discriminate urban and non-urban area in polarimetric synthetic aperture radar (PolSAR) application. Traditional urban-area extraction methods based on modelbased target decomposition usually misclassified ground-trunk structure as urban-area or misclassified rotated urbanarea as forest. This paper introduces another feature named orientation angle to improve urban-area extraction scheme for the accurate mapping in urban by PolSAR image. The proposed method takes randomness of orientation angle into account for restriction of urban area first and, subsequently, implements rotation angle to improve results that oriented urban areas are recognized as double-bounce objects from volume scattering. ESAR L-band PolSAR data of the Oberpfaffenhofen Test Site Area was used to validate the proposed algorithm.

24 CFR 570.800 - Urban renewal regulations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Urban renewal regulations. 570.800 Section 570.800 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND...

24 CFR 570.800 - Urban renewal regulations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Urban renewal regulations. 570.800 Section 570.800 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND...

Contribution of urbanization to the increase of extreme heat events in an urban agglomeration in east China: Urbanization and the Increase of EHEs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Xuchao; Ruby Leung, L.; Zhao, Naizhuo

The urban agglomeration of Yangtze River Delta (YRD) is emblematic of China’s rapid urbanization during the past decades. Based on homogenized daily maximum and minimum temperature data, the contributions of urbanization to trends of extreme temperature indices (ETIs) during summer in YRD are evaluated. Dynamically classifying the observational stations into urban and rural areas, this study presents unexplored changes in temperature extremes during the past four decades in the YRD region and quantifies the amplification of the positive trends in ETIs by the urban heat island effect. Overall, urbanization contributes to more than one third in the increase of intensitymore » of extreme heat events in the region, which is comparable to the contribution of greenhouse gases. Compared to rural stations, more notable shifts to the right in the probability distribution of temperature and ETIs were observed in urban stations.« less

Contaminants in urban waters—Science capabilities of the U.S. Geological Survey

USGS Publications Warehouse

Jastram, John D.; Hyer, Kenneth E.

2016-04-29

Streams and estuaries with urban watersheds commonly exhibit increased streamflow and decreased base flow; diminished stream-channel stability; excessive amounts of contaminants such as pesticides, metals, industrial and municipal waste, and combustion products; and alterations to biotic community structure. Collectively, these detrimental effects have been termed the “urban-stream syndrome.” Water-resource managers seek to lessen the effects on receiving water bodies of new urban development and remediate the effects in areas of existing urbanization. Similarly, the scientific community has produced extensive research on these topics, with researchers from the U.S. Geological Survey (USGS) leading many studies of urban streams and the processes responsible for the urban-stream syndrome. Increasingly, USGS studies are evaluating the effects of management and restoration activities to better understand how urban waters respond to the implementation of management practices. The USGS has expertise in collecting and interpreting data for many physical, chemical, and ecological processes in urban waters and, thus, provides holistic assessments to inform managers of urban water resources.

Assessment of sustainable urban transport development based on entropy and unascertained measure

PubMed Central

Li, Yancang; Yang, Jing; Li, Yijie

2017-01-01

To find a more effective method for the assessment of sustainable urban transport development, the comprehensive assessment model of sustainable urban transport development was established based on the unascertained measure. On the basis of considering the factors influencing urban transport development, the comprehensive assessment indexes were selected, including urban economical development, transport demand, environment quality and energy consumption, and the assessment system of sustainable urban transport development was proposed. In view of different influencing factors of urban transport development, the index weight was calculated through the entropy weight coefficient method. Qualitative and quantitative analyses were conducted according to the actual condition. Then, the grade was obtained by using the credible degree recognition criterion from which the urban transport development level can be determined. Finally, a comprehensive assessment method for urban transport development was introduced. The application practice showed that the method can be used reasonably and effectively for the comprehensive assessment of urban transport development. PMID:29084281

AVIRIS data and neural networks applied to an urban ecosystem

NASA Technical Reports Server (NTRS)

Ridd, Merrill K.; Ritter, Niles D.; Bryant, Nevin A.; Green, Robert O.

1992-01-01

Urbanization is expanding on every continent. Although urban/industrial areas occupy a small percentage of the total landscape of the earth, their influence extends far beyond their borders, affecting terrestrial, aquatic, and atmospheric systems globally. Yet little has been done to characterize urban ecosystems of their linkages to other systems horizontally or vertically. With remote sensing we now have the tools to characterize, monitor, and model urban landscapes world-wide. However, the remote sensing performed on cities so far has concentrated on land-use patterns as distinct from land-cover or composition. The popular Anderson system is entirely land-use oriented in urban areas. This paper begins with the premise that characterizing the biophysical composition of urban environments is fundamental to understanding urban/industrial ecosystems, and, in turn, supports the modeling of other systems interfacing with urban systems. Further, it is contended that remote sensing is a tool poised to provide the biophysical composition data to characterize urban landscapes.

Song convergence in multiple urban populations of silvereyes (Zosterops lateralis)

PubMed Central

Potvin, Dominique A; Parris, Kirsten M

2012-01-01

Recent studies have revealed differences between urban and rural vocalizations of numerous bird species. These differences include frequency shifts, amplitude shifts, altered song speed, and selective meme use. If particular memes sung by urban populations are adapted to the urban soundscape, “urban-typical” calls, memes, or repertoires should be consistently used in multiple urban populations of the same species, regardless of geographic location. We tested whether songs or contact calls of silvereyes (Zosterops lateralis) might be subject to such convergent cultural evolution by comparing syllable repertoires of geographically dispersed urban and rural population pairs throughout southeastern Australia. Despite frequency and tempo differences between urban and rural calls, call repertoires were similar between habitat types. However, certain song syllables were used more frequently by birds from urban than rural populations. Partial redundancy analysis revealed that both geographic location and habitat characteristics were important predictors of syllable repertoire composition. These findings suggest convergent cultural evolution: urban populations modify both song and call syllables from their local repertoire in response to noise. PMID:22957198

Song convergence in multiple urban populations of silvereyes (Zosterops lateralis).

PubMed

Potvin, Dominique A; Parris, Kirsten M

2012-08-01

Recent studies have revealed differences between urban and rural vocalizations of numerous bird species. These differences include frequency shifts, amplitude shifts, altered song speed, and selective meme use. If particular memes sung by urban populations are adapted to the urban soundscape, "urban-typical" calls, memes, or repertoires should be consistently used in multiple urban populations of the same species, regardless of geographic location. We tested whether songs or contact calls of silvereyes (Zosterops lateralis) might be subject to such convergent cultural evolution by comparing syllable repertoires of geographically dispersed urban and rural population pairs throughout southeastern Australia. Despite frequency and tempo differences between urban and rural calls, call repertoires were similar between habitat types. However, certain song syllables were used more frequently by birds from urban than rural populations. Partial redundancy analysis revealed that both geographic location and habitat characteristics were important predictors of syllable repertoire composition. These findings suggest convergent cultural evolution: urban populations modify both song and call syllables from their local repertoire in response to noise.

Natural selection on plant physiological traits in an urban environment

NASA Astrophysics Data System (ADS)

Lambrecht, Susan C.; Mahieu, Stephanie; Cheptou, Pierre-Olivier

2016-11-01

Current rates of urbanization are creating new opportunities for studying urban plant ecology, but our knowledge of urban plant physiology lags behind that of other ecosystems. Moreover, higher temperatures, elevated CO2, and increased inorganic nitrogen deposition along with altered moisture regimes of urban as compared to rural areas creates a compelling analog for studying adaptations of plants to climate change. We grew plants under common conditions in a greenhouse to determine whether populations of Crepis sancta (Asteraceae) differed in phenological, morphological, and physiological traits. We also used a field experiment to test for natural selection on these traits in urban Montpellier, France. Urban plants flowered and senesced later than rural plants, and natural selection favored later phenology in the urban habitat. Natural selection also favored larger plants with more leaves, and increased photosynthesis and leaf nitrogen concentration. Ours is the first study to document selection on plant functional traits in an urban habitat and, as such, advances our understanding of urban plant ecology and possible adaptations to climate change.

Analysing the impact of urban areas patterns on the mean annual flow of 43 urbanized catchments

NASA Astrophysics Data System (ADS)

Salavati, B.; Oudin, L.; Furusho, C.; Ribstein, P.

2015-06-01

It is often argued that urban areas play a significant role in catchment hydrology, but previous studies reported disparate results of urbanization impacts on stream flow. This might stem either from the difficulty to quantify the historical flow changes attributed to urbanization only (and not climate variability) or from the inability to decipher what type of urban planning is more critical for flows. In this study, we applied a hydrological model on 43 urban catchments in the United States to quantify the flow changes attributable to urbanization. Then, we tried to relate these flow changes to the changes of urban/impervious areas of the catchments. We argue that these spatial changes of urban areas can be more precisely characterized by landscape metrics, which enable analysing the patterns of historical urban growth. Landscape metrics combine the richness (the number) and evenness (the spatial distribution) of patch types represented on the landscape. Urbanization patterns within the framework of patch analysis have been widely studied but, to our knowledge, previous research works had not linked them to catchments hydrological behaviours. Our results showed that the catchments with larger impervious areas and larger mean patch areas are likely to have larger increase of runoff yield.

Causes and Disparities in Death Rates Among Urban American Indian and Alaska Native Populations, 1999–2009

PubMed Central

Espey, David K.; Groom, Amy V.; Phillips, Leslie E.; Haverkamp, Donald S.; Stanley, Sandte L.

2016-01-01

Objectives. To characterize the leading causes of death for the urban American Indian/Alaska Native (AI/AN) population and compare with urban White and rural AI/AN populations. Methods. We linked Indian Health Service patient registration records with the National Death Index to reduce racial misclassification in death certificate data. We calculated age-adjusted urban AI/AN death rates for the period 1999–2009 and compared those with corresponding urban White and rural AI/AN death rates. Results. The top-5 leading causes of death among urban AI/AN persons were heart disease, cancer, unintentional injury, diabetes, and chronic liver disease and cirrhosis. Compared with urban White persons, urban AI/AN persons experienced significantly higher death rates for all top-5 leading causes. The largest disparities were for diabetes and chronic liver disease and cirrhosis. In general, urban and rural AI/AN persons had the same leading causes of death, although urban AI/AN persons had lower death rates for most conditions. Conclusions. Urban AI/AN persons experience significant disparities in death rates compared with their White counterparts. Public health and clinical interventions should target urban AI/AN persons to address behaviors and conditions contributing to health disparities. PMID:26890168

Nitrogen cycling process rates across urban ecosystems.

PubMed

Reisinger, Alexander J; Groffman, Peter M; Rosi-Marshall, Emma J

2016-09-21

Nitrogen (N) pollution of freshwater, estuarine, and marine ecosystems is widespread and has numerous environmental and economic impacts. A portion of this excess N comes from urban watersheds comprised of natural and engineered ecosystems which can alter downstream N export. Studies of urban N cycling have focused on either specific ecosystems or on watershed-scale mass balances. Comparisons of specific N transformations across ecosystems are required to contextualize rates from individual studies. Here we reviewed urban N cycling in terrestrial, aquatic, and engineered ecosystems, and compared N processing in these urban ecosystem types to native reference ecosystems. We found that net N mineralization and net nitrification rates were enhanced in urban forests and riparian zones relative to reference ecosystems. Denitrification was highly variable across urban ecosystem types, but no significant differences were found between urban and reference denitrification rates. When focusing on urban streams, ammonium uptake was more rapid than nitrate uptake in urban streams. Additionally, reduction of stormwater runoff coupled with potential decreases in N concentration suggests that green infrastructure may reduce downstream N export. Despite multiple environmental stressors in urban environments, ecosystems within urban watersheds can process and transform N at rates similar to or higher than reference ecosystems. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The ethics of smart cities and urban science

PubMed Central

2016-01-01

Software-enabled technologies and urban big data have become essential to the functioning of cities. Consequently, urban operational governance and city services are becoming highly responsive to a form of data-driven urbanism that is the key mode of production for smart cities. At the heart of data-driven urbanism is a computational understanding of city systems that reduces urban life to logic and calculative rules and procedures, which is underpinned by an instrumental rationality and realist epistemology. This rationality and epistemology are informed by and sustains urban science and urban informatics, which seek to make cities more knowable and controllable. This paper examines the forms, practices and ethics of smart cities and urban science, paying particular attention to: instrumental rationality and realist epistemology; privacy, datafication, dataveillance and geosurveillance; and data uses, such as social sorting and anticipatory governance. It argues that smart city initiatives and urban science need to be re-cast in three ways: a re-orientation in how cities are conceived; a reconfiguring of the underlying epistemology to openly recognize the contingent and relational nature of urban systems, processes and science; and the adoption of ethical principles designed to realize benefits of smart cities and urban science while reducing pernicious effects. This article is part of the themed issue ‘The ethical impact of data science’. PMID:28336794

The ethics of smart cities and urban science.

PubMed

Kitchin, Rob

2016-12-28

Software-enabled technologies and urban big data have become essential to the functioning of cities. Consequently, urban operational governance and city services are becoming highly responsive to a form of data-driven urbanism that is the key mode of production for smart cities. At the heart of data-driven urbanism is a computational understanding of city systems that reduces urban life to logic and calculative rules and procedures, which is underpinned by an instrumental rationality and realist epistemology. This rationality and epistemology are informed by and sustains urban science and urban informatics, which seek to make cities more knowable and controllable. This paper examines the forms, practices and ethics of smart cities and urban science, paying particular attention to: instrumental rationality and realist epistemology; privacy, datafication, dataveillance and geosurveillance; and data uses, such as social sorting and anticipatory governance. It argues that smart city initiatives and urban science need to be re-cast in three ways: a re-orientation in how cities are conceived; a reconfiguring of the underlying epistemology to openly recognize the contingent and relational nature of urban systems, processes and science; and the adoption of ethical principles designed to realize benefits of smart cities and urban science while reducing pernicious effects.This article is part of the themed issue 'The ethical impact of data science'. © 2016 The Author(s).

Land use patterns and urbanization in the holy city of Varanasi, India: a scenario.

PubMed

Kumar, Manoj; Mukherjee, Nivedita; Sharma, Gyan Prakash; Raghubanshi, A S

2010-08-01

Rapid urbanization and increasing land use changes due to population and economic growth in selected landscapes is being witnessed of late in India and other developing countries. The cities are expanding in all directions resulting in large-scale urban sprawl and changes in urban land use. The spatial pattern of such changes is clearly noticed on the urban fringes or city peripheral rural areas than in the city center. In fact, this is reflected in changing urban land use patterns. There is an urgent need to accurately describe land use changes for planning and sustainable management. In the recent times, remote sensing is gaining importance as vital tool in the analysis and integration of spatial data. This study intends to estimate land use pattern in a planned and unplanned urban setup and also to analyze the impact of change in land use pattern in the Varanasi urban environment. The results indicate that the planned urban setup had a higher tree cover to that of unplanned area in the Varanasi City, although a considerable disparity existed within the planned urban setups. The results emphasize the need to critically review concepts of urban planning and give more consideration to the preservation and management of urban tree cover/greenspace.

Big city Bombus: using natural history and land-use history to find significant environmental drivers in bumble-bee declines in urban development.

PubMed

Glaum, Paul; Simao, Maria-Carolina; Vaidya, Chatura; Fitch, Gordon; Iulinao, Benjamin

2017-05-01

Native bee populations are critical sources of pollination. Unfortunately, native bees are declining in abundance and diversity. Much of this decline comes from human land-use change. While the effects of large-scale agriculture on native bees are relatively well understood, the effects of urban development are less clear. Understanding urbanity's effect on native bees requires consideration of specific characteristics of both particular bee species and their urban landscape. We surveyed bumble-bee ( Bombus spp.) abundance and diversity in gardens across multiple urban centres in southeastern Michigan. There are significant declines in Bombus abundance and diversity associated with urban development when measured on scales in-line with Bombus flight ability. These declines are entirely driven by declines in females; males showed no response to urbanization. We hypothesize that this is owing to differing foraging strategies between the sexes, and it suggests reduced Bombus colony density in more urban areas. While urbanity reduced Bombus prevalence, results in Detroit imply that 'shrinking cities' potentially offer unique urban paradigms that must be considered when studying wild bee ecology. Results show previously unidentified differences in the effects of urbanity on female and male bumble-bee populations and suggest that urban landscapes can be managed to support native bee conservation.

Big city Bombus: using natural history and land-use history to find significant environmental drivers in bumble-bee declines in urban development

PubMed Central

Simao, Maria-Carolina; Vaidya, Chatura; Fitch, Gordon; Iulinao, Benjamin

2017-01-01

Native bee populations are critical sources of pollination. Unfortunately, native bees are declining in abundance and diversity. Much of this decline comes from human land-use change. While the effects of large-scale agriculture on native bees are relatively well understood, the effects of urban development are less clear. Understanding urbanity's effect on native bees requires consideration of specific characteristics of both particular bee species and their urban landscape. We surveyed bumble-bee (Bombus spp.) abundance and diversity in gardens across multiple urban centres in southeastern Michigan. There are significant declines in Bombus abundance and diversity associated with urban development when measured on scales in-line with Bombus flight ability. These declines are entirely driven by declines in females; males showed no response to urbanization. We hypothesize that this is owing to differing foraging strategies between the sexes, and it suggests reduced Bombus colony density in more urban areas. While urbanity reduced Bombus prevalence, results in Detroit imply that ‘shrinking cities’ potentially offer unique urban paradigms that must be considered when studying wild bee ecology. Results show previously unidentified differences in the effects of urbanity on female and male bumble-bee populations and suggest that urban landscapes can be managed to support native bee conservation. PMID:28573023

Urbanization influences on aquatic communities in northeastern Illinois streams

USGS Publications Warehouse

Fitzpatrick, F.A.; Harris, M.A.; Arnold, T.L.; Richards, K.D.

2004-01-01

Biotic indices and sediment trace element concentrations for 43 streams in northeastern Illinois (Chicago area) from the 1980s and 1990s were examined along an agricultural to urban land cover gradient to explore the relations among biotic integrity, sediment chemistry, and urbanization. The Illinois fish Alternative Index of Biotic Integrity (AIBI) ranged from poor to excellent in agricultural/rural streams, but streams with more than 10 percent watershed urban land (about 500 people/mi2) had fair or poor index scores. A macroinvertebrate index (MBI) showed similar trends. A qualitative habitat index (PIBI) did not correlate to either urban indicator. The AIBI and MBI correlated with urban associated sediment trace element concentrations. Elevated copper concentrations in sediment occurred in streams with greater than 40 percent watershed urban land. The number of intolerant fish species and modified index of biotic integrity scores increased in some rural, urbanizing, and urban streams from the 1980s to 1990s, with the largest increases occurring in rural streams with loamy/sandy surficial deposits. However, smaller increases also occurred in urban streams with clayey surficial deposits and over 50 percent watershed urban land. These data illustrate the potentially complex spatial and temporal relations among biotic integrity, sediment chemistry, watershed urban land, population density, and regional and local geologic setting.

Rural-urban differences of neonatal mortality in a poorly developed province of China.

PubMed

Yi, Bin; Wu, Li; Liu, Hong; Fang, Weimin; Hu, Yang; Wang, Youjie

2011-06-18

The influence of rural-urban disparities in children's health on neonatal death in disadvantaged areas of China is poorly understood. In this study of rural and urban populations in Gansu province, a disadvantaged province of China, we describe the characteristics and mortality of newborn infants and evaluated rural-urban differences of neonatal death. We analyzed all neonatal deaths in the data from the Surveillance System of Child Death in Gansu Province, China from 2004 to 2009. We calculated all-cause neonatal mortality rates (NMR) and cause-specific death rates for infants born to rural or urban mothers during 2004-09. Rural-urban classifications were determined based on the residence registry system of China. Chi-square tests were used to compare differences of infant characteristics and cause-specific deaths by rural-urban maternal residence. Overall, NMR fell in both rural and urban populations during 2004-09. Average NMR for rural and urban populations was 17.8 and 7.5 per 1000 live births, respectively. For both rural and urban newborn infants, the four leading causes of death were birth asphyxia, preterm or low birth weight, congenital malformation, and pneumonia. Each cause-specific death rate was higher in rural infants than in urban infants. More rural than urban neonates died out of hospital or did not receive medical care before death. Neonatal mortality declined dramatically both in urban and rural groups in Gansu province during 2004-09. However, profound disparities persisted between rural and urban populations. Strategies that address inequalities of accessibility and quality of health care are necessary to improve neonatal health in rural settings in China.

Indicators to support healthy urban gardening in urban management.

PubMed

Schram-Bijkerk, Dieneke; Otte, Piet; Dirven, Liesbet; Breure, Anton M

2018-04-15

Urban gardening is part of a trend towards more parks and green areas in cities, consumption of organic, locally grown products, and a closer relationship with one's own living environment. Our literature review shows that urban gardens provide opportunities for physical activity and allow people to consume homegrown fruit and vegetables. Urban gardens may also reduce stress levels of gardeners and improve social cohesion. In this way, they can help to prevent health problems. Good quality of urban soil and the functioning of soil ecosystems are indispensable prerequisites for these. We developed a framework that shows how ecosystem health and human health are interconnected in urban gardening, by placing it in the context of urban green space management and valuation. This study yields a set of indicators, which can be used to assess soil ecosystem services and health impacts. They may provide a basis for the evolving dialogue in decision-making processes and partnership activities in urban management. Recognizing the potential effects and discussing what is important to whom, might be enough to find synergies. Importantly, the initiators of urban gardens are often citizens, who seek support from other stakeholders. The social network established by gardens may contribute to health-enabling, cohesive communities involved with their living environment. To maximize health benefits, it is useful to make the urban gardens accessible to many people. This study suggests that urban gardens deserve a position in urban green space management as they may help to address societal challenges like urbanization, health and well-being in aging populations and climate adaptation. Copyright © 2017 Elsevier B.V. All rights reserved.

Climate shocks and rural-urban migration in Mexico: Exploring nonlinearities and thresholds.

PubMed

Nawrotzki, Raphael J; DeWaard, Jack; Bakhtsiyarava, Maryia; Ha, Jasmine Trang

2017-01-01

Adverse climatic conditions may differentially drive human migration patterns between rural and urban areas, with implications for changes in population composition and density, access to infrastructure and resources, and the delivery of essential goods and services. However, there is little empirical evidence to support this notion. In this study, we investigate the relationship between climate shocks and migration between rural and urban areas within Mexico. We combine individual records from the 2000 and 2010 Mexican censuses (n=683,518) with high-resolution climate data from Terra Populus that are linked to census data at the municipality level (n=2,321). We measure climate shocks as monthly deviation from a 30-year (1961-1990) long-term climate normal period, and uncover important nonlinearities using quadratic and cubic specifications. Satellite-based measures of urban extents allow us to classify migrant-sending and migrant-receiving municipalities as rural or urban to examine four internal migration patterns: rural-urban, rural-rural, urban-urban, and urban-rural. Among our key findings, results from multilevel models reveal that each additional drought month increases the odds of rural-urban migration by 3.6%. In contrast, the relationship between heat months and rural-urban migration is nonlinear. After a threshold of ~34 heat months is surpassed, the relationship between heat months and rural-urban migration becomes positive and progressively increases in strength. Policy and programmatic interventions may therefore reduce climate induced rural-urban migration in Mexico through rural climate change adaptation initiatives, while also assisting rural migrants in finding employment and housing in urban areas to offset population impacts.

[Contribution of migrations to the process of urbanization].

PubMed

Bocquier, P

1997-10-01

An average of 22% of the populations of the Sahel countries resided in urban areas in the mid-1970s, a lower level than in the rest of sub-Saharan Africa. The proportion urban has increased by about 5.5% annually over the past 2 decades. By 1993, four Sahel countries had over 30% of their populations in urban areas, and only Burkina Faso had less than 20% urban. The landlocked Sahel countries of Burkina Faso, Mali, Niger, and Chad have maintained rates of urbanization comparable to those of the coastal countries (Cape Verde, Gambia, Mauritania, and Senegal), which had more significant levels of urbanization in the past. The rate of growth of the urban population of all of sub-Saharan Africa was around 5.0% during the past 20 years. Only Dakar among the Sahel capitals has a population of over 1 million. Cities are small, and the urban environment is usually limited to the capital. In Guinea-Bissau, for example, the capital concentrates nearly 85% of the urban population. The increased rates of urbanization are due mainly to migration. In the landlocked countries covered by surveys of the Migration and Urbanization Networks in Western Africa (Burkina Faso, Mali, and Niger), the rural exodus was directed primarily to other countries. In Senegal and Mauritania, on the other hand, around two-thirds of migrations were internal. Women contribute more than men to urban growth in the Sahel. Returning migrants also show a strong preference for capital cities. Labor markets are international for men but national for women. Urban unemployment rates in the Sahel countries studied were lower for migrants than nonmigrants.

Climate shocks and rural-urban migration in Mexico: Exploring nonlinearities and thresholds

PubMed Central

Nawrotzki, Raphael J.; DeWaard, Jack; Bakhtsiyarava, Maryia; Ha, Jasmine Trang

2016-01-01

Adverse climatic conditions may differentially drive human migration patterns between rural and urban areas, with implications for changes in population composition and density, access to infrastructure and resources, and the delivery of essential goods and services. However, there is little empirical evidence to support this notion. In this study, we investigate the relationship between climate shocks and migration between rural and urban areas within Mexico. We combine individual records from the 2000 and 2010 Mexican censuses (n=683,518) with high-resolution climate data from Terra Populus that are linked to census data at the municipality level (n=2,321). We measure climate shocks as monthly deviation from a 30-year (1961-1990) long-term climate normal period, and uncover important nonlinearities using quadratic and cubic specifications. Satellite-based measures of urban extents allow us to classify migrant-sending and migrant-receiving municipalities as rural or urban to examine four internal migration patterns: rural-urban, rural-rural, urban-urban, and urban-rural. Among our key findings, results from multilevel models reveal that each additional drought month increases the odds of rural-urban migration by 3.6%. In contrast, the relationship between heat months and rural-urban migration is nonlinear. After a threshold of ~34 heat months is surpassed, the relationship between heat months and rural-urban migration becomes positive and progressively increases in strength. Policy and programmatic interventions may therefore reduce climate induced rural-urban migration in Mexico through rural climate change adaptation initiatives, while also assisting rural migrants in finding employment and housing in urban areas to offset population impacts. PMID:28435176

Urban and peri-urban precipitation and air temperature trends in mega cities of the world using multiple trend analysis methods

NASA Astrophysics Data System (ADS)

Ajaaj, Aws A.; Mishra, Ashok K.; Khan, Abdul A.

2018-04-01

Urbanization plays an important role in altering local to regional climate. In this study, the trends in precipitation and the air temperature were investigated for urban and peri-urban areas of 18 mega cities selected from six continents (representing a wide range of climatic patterns). Multiple statistical tests were used to examine long-term trends in annual and seasonal precipitation and air temperature for the selected cities. The urban and peri-urban areas were classified based on the percentage of land imperviousness. Through this study, it was evident that removal of the lag-k serial correlation caused a reduction of approximately 20 to 30% in significant trend observability for temperature and precipitation data. This observation suggests that appropriate trend analysis methodology for climate studies is necessary. Additionally, about 70% of the urban areas showed higher positive air temperature trends, compared with peri-urban areas. There were not clear trend signatures (i.e., mix of increase or decrease) when comparing urban vs peri-urban precipitation in each selected city. Overall, cities located in dry areas, for example, in Africa, southern parts of North America, and Eastern Asia, showed a decrease in annual and seasonal precipitation, while wetter conditions were favorable for cities located in wet regions such as, southeastern South America, eastern North America, and northern Europe. A positive relationship was observed between decadal trends of annual/seasonal air temperature and precipitation for all urban and peri-urban areas, with a higher rate being observed for urban areas.

Dynamics of Hierarchical Urban Green Space Patches and Implications for Management Policy.

PubMed

Yu, Zhoulu; Wang, Yaohui; Deng, Jinsong; Shen, Zhangquan; Wang, Ke; Zhu, Jinxia; Gan, Muye

2017-06-06

Accurately quantifying the variation of urban green space is the prerequisite for fully understanding its ecosystem services. However, knowledge about the spatiotemporal dynamics of urban green space is still insufficient due to multiple challenges that remain in mapping green spaces within heterogeneous urban environments. This paper uses the city of Hangzhou to demonstrate an analysis methodology that integrates sub-pixel mapping technology and landscape analysis to fully investigate the spatiotemporal pattern and variation of hierarchical urban green space patches. Firstly, multiple endmember spectral mixture analysis was applied to time series Landsat data to derive green space coverage at the sub-pixel level. Landscape metric analysis was then employed to characterize the variation pattern of urban green space patches. Results indicate that Hangzhou has experienced a significant loss of urban greenness, producing a more fragmented and isolated vegetation landscape. Additionally, a remarkable amelioration of urban greenness occurred in the city core from 2002 to 2013, characterized by the significant increase of small-sized green space patches. The green space network has been formed as a consequence of new urban greening strategies in Hangzhou. These strategies have greatly fragmented the built-up areas and enriched the diversity of the urban landscape. Gradient analysis further revealed a distinct pattern of urban green space landscape variation in the process of urbanization. By integrating both sub-pixel mapping technology and landscape analysis, our approach revealed the subtle variation of urban green space patches which are otherwise easy to overlook. Findings from this study will help us to refine our understanding of the evolution of heterogeneous urban environments.

Agricultural implications of providing soil-based constraints on urban expansion: Land use forecasts to 2050.

PubMed

Smidt, Samuel J; Tayyebi, Amin; Kendall, Anthony D; Pijanowski, Bryan C; Hyndman, David W

2018-07-01

Urbanization onto adjacent farmlands directly reduces the agricultural area available to meet the resource needs of a growing society. Soil conservation is a common objective in urban planning, but little focus has been placed on targeting soil value as a metric for conservation. This study assigns commodity and water storage values to the agricultural soils across all of the watersheds in Michigan's Lower Peninsula to evaluate how cities might respond to a soil conservation-based urbanization strategy. Land Transformation Model (LTM) simulations representing both traditional and soil conservation-based urbanization, are used to forecast urban area growth from 2010 to 2050 at five year intervals. The expansion of urban areas onto adjacent farmland is then evaluated to quantify the conservation effects of soil-based development. Results indicate that a soil-based protection strategy significantly conserves total farmland, especially more fertile soils within each soil type. In terms of revenue, ∼$88 million (in current dollars) would be conserved in 2050 using soil-based constraints, with the projected savings from 2011 to 2050 totaling more than $1.5 billion. Soil-based urbanization also increased urban density for each major metropolitan area. For example, there were 94,640 more acres directly adjacent to urban land by 2050 under traditional development compared to the soil-based urbanization strategy, indicating that urban sprawl was more tightly contained when including soil value as a metric to guide development. This study indicates that implementing a soil-based urbanization strategy would better satisfy future agricultural resource needs than traditional urban planning. Copyright © 2018. Published by Elsevier Ltd.

An Assessment of the Impact of Urbanization on Soil Erosion in Inner Mongolia.

PubMed

Wang, Li-Yan; Xiao, Yi; Rao, En-Ming; Jiang, Ling; Xiao, Yang; Ouyang, Zhi-Yun

2018-03-19

Inner Mongolia, an autonomous region of the People's Republic of China, has experienced severe soil erosion following a period of rapid economic development and urbanization. To investigate how urbanization has influenced the extent of soil erosion in Inner Mongolia, we used urbanization and soil erosion data from 2000 through 2010 to determine the relationship between urbanization and soil erosion patterns. Two empirical equations-the Revised Universal Soil Loss Equation (RUSLE) and the Revised Wind Erosion Equation (RWEQ)-were used to estimate the intensity of soil erosion, and we performed backward linear regression to model how it changed with greater urbanization. There was an apparent increase in the rate of urbanization and a decrease in the area affected by soil erosion in 2010 compared to the corresponding values for 2000. The urban population stood at 11.32 million in 2010, which represented a 16.47% increase over that in 2000. The area affected by soil erosion in 2000 totaled 704,817 km², yet it had decreased to 674,135 km² by 2010. However, a path of modest urban development (rural-urban mitigation) and reasonable industrial structuring (the development of GDP-2) may partially reduce urbanization's ecological pressure and thus indirectly reduce the threat of soil erosion to human security. Therefore, to better control soil erosion in Inner Mongolia during the process of urbanization, the current model of economic development should be modified to improve the eco-efficiency of urbanization, while also promoting new modes of urbanization that are environmentally sustainable, cost-effective, and conserve limited resources.

Dynamics of Hierarchical Urban Green Space Patches and Implications for Management Policy

PubMed Central

Yu, Zhoulu; Wang, Yaohui; Deng, Jinsong; Shen, Zhangquan; Wang, Ke; Zhu, Jinxia; Gan, Muye

2017-01-01

Accurately quantifying the variation of urban green space is the prerequisite for fully understanding its ecosystem services. However, knowledge about the spatiotemporal dynamics of urban green space is still insufficient due to multiple challenges that remain in mapping green spaces within heterogeneous urban environments. This paper uses the city of Hangzhou to demonstrate an analysis methodology that integrates sub-pixel mapping technology and landscape analysis to fully investigate the spatiotemporal pattern and variation of hierarchical urban green space patches. Firstly, multiple endmember spectral mixture analysis was applied to time series Landsat data to derive green space coverage at the sub-pixel level. Landscape metric analysis was then employed to characterize the variation pattern of urban green space patches. Results indicate that Hangzhou has experienced a significant loss of urban greenness, producing a more fragmented and isolated vegetation landscape. Additionally, a remarkable amelioration of urban greenness occurred in the city core from 2002 to 2013, characterized by the significant increase of small-sized green space patches. The green space network has been formed as a consequence of new urban greening strategies in Hangzhou. These strategies have greatly fragmented the built-up areas and enriched the diversity of the urban landscape. Gradient analysis further revealed a distinct pattern of urban green space landscape variation in the process of urbanization. By integrating both sub-pixel mapping technology and landscape analysis, our approach revealed the subtle variation of urban green space patches which are otherwise easy to overlook. Findings from this study will help us to refine our understanding of the evolution of heterogeneous urban environments. PMID:28587309

Global Urban Mapping and Modeling for Sustainable Urban Development

NASA Astrophysics Data System (ADS)

Zhou, Y.; Li, X.; Asrar, G.; Yu, S.; Smith, S.; Eom, J.; Imhoff, M. L.

2016-12-01

In the past several decades, the world has experienced fast urbanization, and this trend is expected to continue for decades to come. Urbanization, one of the major land cover and land use changes (LCLUC), is becoming increasingly important in global environmental changes, such as urban heat island (UHI) growth and vegetation phenology change. Better scientific insights and effective decision-making unarguably require reliable science-based information on spatiotemporal changes in urban extent and their environmental impacts. In this study, we developed a globally consistent 20-year urban map series to evaluate the time-reactive nature of global urbanization from the nighttime lights remote sensing data, and projected future urban expansion in the 21st century by employing an integrated modeling framework (Zhou et al. 2014, Zhou et al. 2015). We then evaluated the impacts of urbanization on building energy use and vegetation phenology that affect both ecosystem services and human health. We extended the modeling capability of building energy use in the Global Change Assessment Model (GCAM) with consideration of UHI effects by coupling the remote sensing based urbanization modeling and explored the impact of UHI on building energy use. We also investigated the impact of urbanization on vegetation phenology by using an improved phenology detection algorithm. The derived spatiotemporal information on historical and potential future urbanization and its implications in building energy use and vegetation phenology will be of great value in sustainable urban design and development for building energy use and human health (e.g., pollen allergy), especially when considered together with other factors such as climate variability and change. Zhou, Y., S. J. Smith, C. D. Elvidge, K. Zhao, A. Thomson & M. Imhoff (2014) A cluster-based method to map urban area from DMSP/OLS nightlights. Remote Sensing of Environment, 147, 173-185. Zhou, Y., S. J. Smith, K. Zhao, M. Imhoff, A. Thomson, B. Bond-Lamberty, G. R. Asrar, X. Zhang, C. He & C. D. Elvidge (2015) A global map of urban extent from nightlights. Environmental Research Letters, 10, 054011.

Urbanization, economic development and health: evidence from China's labor-force dynamic survey.

PubMed

Chen, Hongsheng; Liu, Ye; Li, Zhigang; Xue, Desheng

2017-11-29

The frequent outbreak of environmental threats in China has resulted in increased criticism regarding the health effects of China's urbanization. Urbanization is a double-edged sword with regard to health in China. Although great efforts have been made to investigate the mechanisms through which urbanization influences health, the effect of both economic development and urbanization on health in China is still unclear, and how urbanization-health (or development-health) relationships vary among different income groups remain poorly understood. To bridge these gaps, the present study investigates the impact of both urbanization and economic development on individuals' self-rated health and its underlying mechanisms in China. We use data from the national scale of the 2014 China Labor-force Dynamics Survey to analyze the impact of China's urbanization and economic development on health. A total of 14,791 individuals were sampled from 401 neighborhoods within 124 prefecture-level cities. Multilevel ordered logistic models were applied. Model results showed an inverted U-shaped relationship between individuals' self-rated health and urbanization rates (with a turning point of urbanization rate at 42.0%) and a positive linear relationship between their self-rated health and economic development. Model results also suggested that the urbanization-health relationship was inverted U-shaped for high- and middle-income people (with a turning point of urbanization rate at 0.0% and 49.2%, respectively), and the development-health relationship was inverted U-shaped for high- and low-income people (with turning points of GDP per capita at 93,462 yuan and 71,333 yuan, respectively) and linear for middle-income people. The impact of urbanization and economic development on health in China is complicated. Careful assessments are needed to understand the health impact of China's rapid urbanization. Social and environmental problems arising from rapid urbanization and economic growth should be addressed. Equitable provision of health services are needed to improve low-income groups' health in highly urbanized cities.

Patterns and determinants of malaria risk in urban and peri-urban areas of Blantyre, Malawi.

PubMed

Mathanga, Don P; Tembo, Atupele Kapito; Mzilahowa, Themba; Bauleni, Andy; Mtimaukenena, Kondwani; Taylor, Terrie E; Valim, Clarissa; Walker, Edward D; Wilson, Mark L

2016-12-08

Although malaria disease in urban and peri-urban areas of sub-Saharan Africa is a growing concern, the epidemiologic patterns and drivers of transmission in these settings remain poorly understood. Factors associated with variation in malaria risk in urban and peri-urban areas were evaluated in this study. A health facility-based, age and location-matched, case-control study of children 6-59 months of age was conducted in four urban and two peri-urban health facilities (HF) of Blantyre city, Malawi. Children with fever who sought care from the same HF were tested for malaria parasites by microscopy and PCR. Those testing positive or negative on both were defined as malaria cases or controls, respectively. A total of 187 cases and 286 controls were studied. In univariate analyses, higher level of education, possession of TV, and electricity in the house were negatively associated with malaria illness; these associations were similar in urban and peri-urban zones. Having travelled in the month before testing was strongly associated with clinical malaria, but only for participants living in the urban zones (OR = 5.1; 95% CI = 1.62, 15.8). Use of long-lasting insecticide nets (LLINs) the previous night was not associated with protection from malaria disease in any setting. In multivariate analyses, electricity in the house, travel within the previous month, and a higher level of education were all associated with decreased odds of malaria disease. Only a limited number of Anopheles mosquitoes were found by aspiration inside the households in the peri-urban areas, and none was collected from the urban households. Travel was the main factor influencing the incidence of malaria illness among residents of urban Blantyre compared with peri-urban areas. Identification and understanding of key mobile demographic groups, their behaviours, and the pattern of parasite dispersal is critical to the design of more targeted interventions for the urban setting.

Local Climate Zones Classification to Urban Planning in the Mega City of São Paulo - SP, Brazil

NASA Astrophysics Data System (ADS)

Gonçalves Santos, Rafael; Saraiva Lopes, António Manuel; Prata-Shimomura, Alessandra

2017-04-01

Local Climate Zones Classification to Urban Planning in the Mega city of São Paulo - SP, Brazil Tropical megacities have presented a strong trend in growing urban. Urban management in megacities has as one of the biggest challenges is the lack of integration of urban climate and urban planning to promote ecologically smart cities. Local Climatic Zones (LCZs) are considered as important and recognized tool for urban climate management. Classes are local in scale, climatic in nature, and zonal in representation. They can be understood as regions of uniform surface cover, structure, material and human activity that have to a unique climate response. As an initial tool to promote urban climate planning, LCZs represent a simple composition of different land coverages (buildings, vegetation, soils, rock, roads and water). LCZs are divided in 17 classes, they are based on surface cover (built fraction, soil moisture, albedo), surface structure (sky view factor, roughness height) and cultural activity (anthropogenic heat flux). The aim of this study is the application of the LCZs classification system in the megacity of São Paulo, Brazil. Located at a latitude of 23° 21' and longitude 46° 44' near to the Tropic of Capricorn, presenting humid subtropical climate (Cfa) with diversified topographies. The megacity of São Paulo currently concentrates 11.890.000 inhabitants is characterized by large urban conglomerates with impermeable surfaces and high verticalization, having as result high urban heat island intensity. The result indicates predominance in urban zones of Compact low-rise, Compact Mid-rise, Compact High-rise and Open Low-rise. Non-urban regions are mainly covered by dense vegetation and water. The LCZs classification system promotes significant advantages for climate sensitive urban planning in the megacity of São Paulo. They offers new perspectives to the management of temperature and urban ventilation and allows the formulation of urban planning guidelines and climatic. Key words: Local Climatic Zones; Urban Panning; Megacities; São Paulo.

Urban Impact at the Urban-Agricultural Interface in Madison, WI: an Ecosystem Modeling Approach

NASA Astrophysics Data System (ADS)

Logan, K. E.; Kucharik, C. J.; Schneider, A.

2009-12-01

Global population and the proportion of people living in urban areas both continue to grow while average urban density is decreasing worldwide. Because urban areas are often located in the most agriculturally productive lands, expansion of the built environment can cause sharp reductions in land available for cultivation. Conversion of land to urban use also significantly alters climate variables. Urban materials differ from natural land covers in terms of albedo, thermal properties, and permeability, altering energy and water cycles. Anthropogenic heat emissions also alter the energy balance in and around a city. Preliminary analysis of urban impacts around Madison, WI, a small city located in a thriving agricultural region, was performed using the National Land Cover Database (NLCD), MODIS albedo products, ground-based observations, and a simulation of urban expansion, within a geographic information system (GIS). Population of the county is expected to increase by 58% while urban density is projected to decrease by 49% between 1992 and 2030, reflecting projected worldwide patterns. Carbon stored in the top 25cm of soil was found to be over 2.5 times greater in remnant prairies than in croplands and was calculated to be even less in urban areas; projected urban development may thus lead to large losses in carbon storage. Albedo measurements also show a significant decrease with urban development. Projected urban expansion between 2001 and 2030 is expected to convert enough agricultural lands to urban areas to result in a loss of 247,000 tons of crop yield in Dane County alone, based on current yields. For a more complete analysis of these impacts, urban parameters are incorporated into a terrestrial ecosystem model known as Agro-IBIS. This approach allows for detailed comparison of energy balance and biogeochemical cycles between local crop systems, lawns, and impervious city surfaces. Changes in these important cycles, in soil carbon storage, and in crop productivity/yield for 1992 - 2001 and projected 2030 development around Madison, WI will be shown.

Multi-Temporal Multi-Sensor Analysis of Urbanization and Environmental/Climate Impact in China for Sustainable Urban Development

NASA Astrophysics Data System (ADS)

Ban, Yifang; Gong, Peng; Gamba, Paolo; Taubenbock, Hannes; Du, Peijun

2016-08-01

The overall objective of this research is to investigate multi-temporal, multi-scale, multi-sensor satellite data for analysis of urbanization and environmental/climate impact in China to support sustainable planning. Multi- temporal multi-scale SAR and optical data have been evaluated for urban information extraction using innovative methods and algorithms, including KTH- Pavia Urban Extractor, Pavia UEXT, and an "exclusion- inclusion" framework for urban extent extraction, and KTH-SEG, a novel object-based classification method for detailed urban land cover mapping. Various pixel- based and object-based change detection algorithms were also developed to extract urban changes. Several Chinese cities including Beijing, Shanghai and Guangzhou are selected as study areas. Spatio-temporal urbanization patterns and environmental impact at regional, metropolitan and city core were evaluated through ecosystem service, landscape metrics, spatial indices, and/or their combinations. The relationship between land surface temperature and land-cover classes was also analyzed.The urban extraction results showed that urban areas and small towns could be well extracted using multitemporal SAR data with the KTH-Pavia Urban Extractor and UEXT. The fusion of SAR data at multiple scales from multiple sensors was proven to improve urban extraction. For urban land cover mapping, the results show that the fusion of multitemporal SAR and optical data could produce detailed land cover maps with improved accuracy than that of SAR or optical data alone. Pixel-based and object-based change detection algorithms developed with the project were effective to extract urban changes. Comparing the urban land cover results from mulitemporal multisensor data, the environmental impact analysis indicates major losses for food supply, noise reduction, runoff mitigation, waste treatment and global climate regulation services through landscape structural changes in terms of decreases in service area, edge contamination and fragmentation. In terms ofclimate impact, the results indicate that land surface temperature can be related to land use/land cover classes.

A Multi-scale Method of Mapping Urban Influence

EPA Science Inventory

Urban development can impact environmental quality and ecosystem services well beyond urban extent. Many methods to map urban areas have been developed and used in the past, but most have simply tried to map existing extent of urban development, and all have been single-scale t...

EFFECT OF URBANIZATION ON FISH ASSEMBLAGES AND HABITAT QUALITY IN A PIEDMONT RIVER BASIN

EPA Science Inventory

We quantified the relationships among urbanization, fishes, and habitat quality to determine how assemblags respond to urbanization and if a habitat quality assessment reflects urban effects on stream ecosystems. We sampled 30 wadeable streams along an urban gradient in the Etow...

Tree Leaf Bacterial Community Structure and Diversity Differ along a Gradient of Urban Intensity

PubMed Central

Messier, Christian; Kembel, Steven W.

2017-01-01

ABSTRACT Tree leaf-associated microbiota have been studied in natural ecosystems but less so in urban settings, where anthropogenic pressures on trees could impact microbial communities and modify their interaction with their hosts. Additionally, trees act as vectors spreading bacterial cells in the air in urban environments due to the density of microbial cells on aerial plant surfaces. Characterizing tree leaf bacterial communities along an urban gradient is thus key to understand the impact of anthropogenic pressures on urban tree-bacterium interactions and on the overall urban microbiome. In this study, we aimed (i) to characterize phyllosphere bacterial communities of seven tree species in urban environments and (ii) to describe the changes in tree phyllosphere bacterial community structure and diversity along a gradient of increasing urban intensity and at two degrees of tree isolation. Our results indicate that, as anthropogenic pressures increase, urban leaf bacterial communities show a reduction in the abundance of the dominant class in the natural plant microbiome, the Alphaproteobacteria. Our work in the urban environment here reveals that the structures of leaf bacterial communities differ along the gradient of urban intensity. The diversity of phyllosphere microbial communities increases at higher urban intensity, also displaying a greater number and variety of associated indicator taxa than the low and medium urban gradient sites. In conclusion, we find that urban environments influence tree bacterial community composition, and our results suggest that feedback between human activity and plant microbiomes could shape urban microbiomes. IMPORTANCE In natural forests, tree leaf surfaces host diverse bacterial communities whose structure and composition are primarily driven by host species identity. Tree leaf bacterial diversity has also been shown to influence tree community productivity, a key function of terrestrial ecosystems. However, most urban microbiome studies have focused on the built environment, improving our understanding of indoor microbial communities but leaving much to be understood, especially in the nonbuilt microbiome. Here, we provide the first multiple-species comparison of tree phyllosphere bacterial structures and diversity along a gradient of urban intensity. We demonstrate that urban trees possess characteristic bacterial communities that differ from those seen with trees in nonurban environments, with microbial community structure on trees influenced by host species identity but also by the gradient of urban intensity and by the degree of isolation from other trees. Our results suggest that feedback between human activity and plant microbiomes could shape urban microbiomes. PMID:29238751

Tree Leaf Bacterial Community Structure and Diversity Differ along a Gradient of Urban Intensity.

PubMed

Laforest-Lapointe, Isabelle; Messier, Christian; Kembel, Steven W

2017-01-01

Tree leaf-associated microbiota have been studied in natural ecosystems but less so in urban settings, where anthropogenic pressures on trees could impact microbial communities and modify their interaction with their hosts. Additionally, trees act as vectors spreading bacterial cells in the air in urban environments due to the density of microbial cells on aerial plant surfaces. Characterizing tree leaf bacterial communities along an urban gradient is thus key to understand the impact of anthropogenic pressures on urban tree-bacterium interactions and on the overall urban microbiome. In this study, we aimed (i) to characterize phyllosphere bacterial communities of seven tree species in urban environments and (ii) to describe the changes in tree phyllosphere bacterial community structure and diversity along a gradient of increasing urban intensity and at two degrees of tree isolation. Our results indicate that, as anthropogenic pressures increase, urban leaf bacterial communities show a reduction in the abundance of the dominant class in the natural plant microbiome, the Alphaproteobacteria . Our work in the urban environment here reveals that the structures of leaf bacterial communities differ along the gradient of urban intensity. The diversity of phyllosphere microbial communities increases at higher urban intensity, also displaying a greater number and variety of associated indicator taxa than the low and medium urban gradient sites. In conclusion, we find that urban environments influence tree bacterial community composition, and our results suggest that feedback between human activity and plant microbiomes could shape urban microbiomes. IMPORTANCE In natural forests, tree leaf surfaces host diverse bacterial communities whose structure and composition are primarily driven by host species identity. Tree leaf bacterial diversity has also been shown to influence tree community productivity, a key function of terrestrial ecosystems. However, most urban microbiome studies have focused on the built environment, improving our understanding of indoor microbial communities but leaving much to be understood, especially in the nonbuilt microbiome. Here, we provide the first multiple-species comparison of tree phyllosphere bacterial structures and diversity along a gradient of urban intensity. We demonstrate that urban trees possess characteristic bacterial communities that differ from those seen with trees in nonurban environments, with microbial community structure on trees influenced by host species identity but also by the gradient of urban intensity and by the degree of isolation from other trees. Our results suggest that feedback between human activity and plant microbiomes could shape urban microbiomes.

Mapping Global Urban Dynamics from Nighttime Lights - 1992 to 2012

NASA Astrophysics Data System (ADS)

Xie, Yanhua

Accurate, up-to-date, and consistent information of urban extent is indispensable for numerous applications central to urban planning, ecosystem management, and environmental assessment and monitoring. However, current large-scale urban extent products are not uniform with respect to urban definition, spatial resolution, thematic representation, and temporal frequency. To fill this gap, this study proposed a method to update and backdate global urban extent from currently available urban maps by using nighttime light (NTL) as the main indicator. The method followed three steps: (1) exploring the spatiotemporal variation of NTL thresholds for mapping urban dynamics from NTL time series and developing an object-based thresholding method (i.e., NTL-OUT method, Xie & Weng, 2016b); (2) spatiotemporally enhancing time-series Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) NTL data for detecting broad-scale urban changes (Xie & Weng, 2017); and (3) detecting global urban dynamics during the period between 1992 and 2012 (i.e., 1992, 1997, 2002, 2007, and 2012) from enhanced OLS NTL time series by using the NTL-OUT method. The results show that global urban extent almost doubled during the period from 1992 to 2012, increasing from 0.52 million to 0.98 million km 2, which accounts for 0.39% and 0.72% of the total global land area, respectively. Regionally, the urbanization level varies by continent, with Europe being the most urbanized, followed by North America, Asia, South America, Africa, and Australia-Oceania. In 1992, the urban extent varied from only 0.1% of total continental land area in Australia-Oceania and Africa to 1.18% in Europe. While the proportion of urban extent in North America increased slightly from 1992 to 2002 (i.e., 0.07%), urban extent increased 0.1% for both Asia and South America. In 2012, over 0.7% of the total land was covered by the human built environment, with 0.2% in Africa and Australia-Oceania and around 0.9% in North America, followed by Asia at 0.84% and South America at 0.73%. The exception is the European urban extent, which was 1.82% of its total land mass. Asia has experienced the most rapid urbanization during the period, converting more than 9,000 km2 non-urban land covers/uses to urbanized land each year. Over 3,000 km2 of urban extent has been added annually to European and North American regions, respectively, followed by South America with over 3,000 km2, Africa with 1,700 km 2, and Australia-Oceania with 300 km2. In addition, the results demonstrate that most regions experienced a more rapid urbanization after the 21st century than the period from 1992 to 2002, especially for Asia and Africa. Accuracy assessment in the contiguous U.S.A. (CONUS) and China showed that the proposed method can update and backdate urban extent with reasonably high accuracy, yielding the mean city-scale RMSE (root mean square error) and Kappa: 27 and 23 km2 and 0.65 and 0.63 for CONUS, and 55 and 60 km2 and 0.59 and 0.60 for China, respectively. It was also revealed that spatial enhancement greatly improved the accuracy of urban updating and backdating by significantly decreasing RMSE and slightly increasing Kappa values; temporal enhancement further reduced RMSE and improved the spatial consistency between estimated and reference urban extent. The study generated time-series comparable urban extent maps from 1992 to 2012 with a 5-year interval, which can be used to explore global urbanization and address its impacts on urbanization-induced social and environmental problems.

Patterning between urban soil color and carbon stocks

EPA Science Inventory

Urban soils are less complex in contrast to non-urban soils due to land management, e.g., fill, demolition, etc. For example, urban soils have fewer horizons than non-urban soils, and are also more likely to have lost the “B” horizon [1]. Along similar lines, we hypothesize that ...

Overview of urban climate

Treesearch

Roscoe R., Jr. Braham

1977-01-01

The broad features of urban climate anomalies are described and explained by combining recent METROMEX data with those from prior studies. The urban heat island is well understood, and urban effects upon cloud nuclei and cloud microstructure are clearly observed and explained in part; but the causes of urban effects upon rainfall remain speculative.

A Survey to Assess Barriers to Urban Teaching Careers

ERIC Educational Resources Information Center

Creasey, Gary; Mays, Jennifer; Lee, Robert; D'Santiago, Verenice

2016-01-01

The "Urban Teaching Barriers" survey was created to assess barriers to urban teaching careers. Pre-service teachers (N = 377) completed this instrument, along with questionnaires that assessed urban teaching intentions and urban teaching self-efficacy. Six barrier domains were identified that tapped concerns over (a) lack of resources,…

Urbanism and Racial Attitudes: A Test of Some Urban Theories.

ERIC Educational Resources Information Center

Wilson, Thomas C.

1984-01-01

National survey data are used to test the relationship between urbanism and racial attitudes among Whites, and a liberalizing effect of urbanism is found. It appears that urbanism liberalizes racial attitudes by increasing equal-status, cooperative, and relatively personal contact between members of racial subcultures. (Author/RDN)

Interdisciplinary Research Topics in Urban Engineering. (A Summary of the Report by the Urban Engineering Study Committee)

ERIC Educational Resources Information Center

Eng Educ, 1969

1969-01-01

Proposes preparation of urban engineers through interdisciplinary systems engineering research in order that technology may be applied to urban problems such as transportation, environment, and housing. Summary of report by the Urban Engineering Study Committee. Complete report available at

24 CFR 510.1 - Multi-family property loans.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Multi-family property loans. 510.1 Section 510.1 Housing and Urban Development Regulations Relating to Housing and Urban Development... URBAN DEVELOPMENT SLUM CLEARANCE AND URBAN RENEWAL SECTION 312 REHABILITATION LOAN PROGRAM § 510.1 Multi...

36 CFR 910.11 - Comprehensive urban planning and design.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Comprehensive urban planning... CORPORATION GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.11 Comprehensive urban planning...

36 CFR 910.13 - Urban design of Washington, DC.

Code of Federal Regulations, 2010 CFR

2010-07-01

... CORPORATION GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.13 Urban design of Washington, DC... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Urban design of Washington...

24 CFR 570.205 - Eligible planning, urban environmental design and policy-planning-management-capacity building...

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 3 2011-04-01 2010-04-01 true Eligible planning, urban... ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT..., urban environmental design and policy-planning-management-capacity building activities. (a) Planning...

36 CFR 910.13 - Urban design of Washington, DC.

Code of Federal Regulations, 2011 CFR

2011-07-01

... CORPORATION GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.13 Urban design of Washington, DC... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Urban design of Washington...

76 FR 12217 - Exempt Discretionary Program Grants (Section 5309) for Urban Circulator Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-04

... redevelopment of urban spaces into walkable mixed use, high density environments. FOR FURTHER INFORMATION... development. FTA's approval to advance the Urban Circulator projects through project development and grant... urban circulators shall be required to submit information that describes the impact of the urban...

An Ecological Examination of an Urban Sixth Grade Physical Education Class

ERIC Educational Resources Information Center

James, Alisa R.; Collier, Douglas

2011-01-01

Background: There are several factors that influence teaching urban physical education. Violence, poverty and irrelevant curricula influence the teaching-learning environment in urban physical education. One approach to urban physical education is to look carefully at the ecology that exists within an urban physical education class. This ecology…

Sustaining Urban Forests

Treesearch

John F. Dwyer; David J. Nowak

2003-01-01

The significance of the urban forest resource and the powerful forces for change in the urban environment make sustainability a critical issue in urban forest management. The diversity, connectedness, and dynamics of the urban forest establish the context for management that will determine the sustainability of forest structure, health, functions, and benefits. A...

Urban Environmental Program in New England | US EPA

EPA Pesticide Factsheets

2017-04-10

The Urban Environmental Program's mission is to improve the environment and enhance the quality of life for urban residents throughout New England by building community capacity to assess and resolve environmental problems, achieving measurable and sustainable improvements in urban communities, and restoring and revitalizing neighborhoods for urban residents.

Urbanization and the wealth of nations.

PubMed

Bloom, David E; Canning, David; Fink, Günther

2008-02-08

The proportion of a country's population living in urban areas is highly correlated with its level of income. Urban areas offer economies of scale and richer market structures, and there is strong evidence that workers in urban areas are individually more productive, and earn more, than rural workers. However, rapid urbanization is also associated with crowding, environmental degradation, and other impediments to productivity. Overall, we find no evidence that the level of urbanization affects the rate of economic growth. Our findings weaken the rationale for either encouraging or discouraging urbanization as part of a strategy for economic growth.

Analyzing the causes of urban waterlogging and sponge city technology in China

NASA Astrophysics Data System (ADS)

Ning, Yun-Fang; Dong, Wen-Yi; Lin, Lu-Sheng; Zhang, Qian

2017-03-01

With the rapid development of social economy in China, increased urban population, and rapid urbanization cause serious problems, for example, a heavy rain in the city inevitably leads to waterlogging, which poses a great threat to the livelihood and property security. Disaster due to urban flood is a key problem that restricts the development of urban ecology in China. The reason is the sharp increase of impermeable surface ratio in urban areas, leading to a decrease in rainfall infiltration and increase in surface runoff. To effectively solve the urban waterlogging, China proposed the construction of sponge city. This paper analyzes and summarizes the reasons for the formation of urban waterlogging, and introduces the concept of the sponge city technology to prevent waterlogging.

Urban Flood Prevention and Early Warning System in Jinan City

NASA Astrophysics Data System (ADS)

Feng, Shiyuan; Li, Qingguo

2018-06-01

The system construction of urban flood control and disaster reduction in China is facing pressure and challenge from new urban water disaster. Under the circumstances that it is difficult to build high standards of flood protection engineering measures in urban areas, it is particularly important to carry out urban flood early warning. In Jinan City, a representative inland area, based on the index system of early warning of flood in Jinan urban area, the method of fuzzy comprehensive evaluation was adopted to evaluate the level of early warning. Based on the cumulative rainfall of 3 hours, the CAflood simulation results based on cellular automaton model of urban flooding were used as evaluation indexes to realize the accuracy and integration of urban flood control early warning.

Study on spatial-temporal change of Changsha-Zhuzhou-Xiangtan urban agglomeration based on DMSP / OLS night light data

NASA Astrophysics Data System (ADS)

Li, Mao; Li, Lel-in

2018-03-01

For the sake of curbing the spreading of Changsha-Zhuzhou-Xiangtan urban agglomeration and spatial disorder in the process of urbanization development on the regional bearing capacity of land resources and ecological environment and assisting to plan the integration process of ChangZhuTan,this paper uses the DMSP/OLS night light data of Chang ZhuTan in 1992 to 2013 to invert the urbanization process index of ChangZhuTan urban agglomeration. Based on the two scales of time and space, this paper analyzes the average index of lights, the speed of urban expansion and urban compactness index et al and studies the temporal and spatial characteristics of ChangZhuTan urban agglomeration in this period.

Modeling Urban Energy Savings Scenarios Using Earth System Microclimate and Urban Morphology

NASA Astrophysics Data System (ADS)

Allen, M. R.; Rose, A.; New, J. R.; Yuan, J.; Omitaomu, O.; Sylvester, L.; Branstetter, M. L.; Carvalhaes, T. M.; Seals, M.; Berres, A.

2017-12-01

We analyze and quantify the relationships among climatic conditions, urban morphology, population, land cover, and energy use so that these relationships can be used to inform energy-efficient urban development and planning. We integrate different approaches across three research areas: earth system modeling; impacts, adaptation and vulnerability; and urban planning in order to address three major gaps in the existing capability in these areas: i) neighborhood resolution modeling and simulation of urban micrometeorological processes and their effect on and from regional climate; ii) projections for future energy use under urbanization and climate change scenarios identifying best strategies for urban morphological development and energy savings; iii) analysis and visualization tools to help planners optimally use these projections.

Projected Regional Climate in 2025 Due to Urban Growth

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Manyin, Michael; Messen, Dmitry

2005-01-01

By 2025, 60 to 80 percent of the world s population will live in urban environments. Additionally, the following facts published by the United Nations further illustrates how cities will evolve in the future. Urban areas in the developing world are growing very rapidly. The urban growth rate will continue to be particularly rapid in the urban areas of less developed regions, averaging 2.4 per cent per year during 2000-2030, consistent with a doubling time of 29 years. The urbanization process will continue worldwide. The concentration of population in cities is expected to continue so that, by 2030, 84 percent of the inhabitants of more developed countries will be urban dwellers. Urbanization impacts the whole hierarchy of human settlements. In 2000,24.8 per cent of the world population lived in urban settlements with fewer than 500,000 inhabitants and by 2015 that proportion will likely rise to 27.1 per cent.

Nocturnal Propagating Thunderstorms May Favor Urban "Hot-Spots": A Model-Based Study over Minneapolis

NASA Technical Reports Server (NTRS)

Ganeshan, Manisha; Murtugudde, Raghu

2015-01-01

High-resolution WRF model sensitivity experiments are carried out (with and without urban land cover) to study urban impacts on nocturnal propagating thunderstorms over the city of Minneapolis. It is found that the storm spatial characteristics, especially the position of the storm cell, are appreciably altered by the presence of urban land cover. The most robust urban instability during stormy conditions is the enhanced surface convergence due to increased frictional drag. No urban impact is visible on the rainfall intensity simulated by the model. The frictional convergence, aided by the nocturnal Urban Heat Island (UHI), appears to be responsible for attracting propagating storms towards the urban center. Advanced modeling experiments are needed to quantify the mechanical and thermal influence along with similar studies in other cities to further investigate the urban impact on the frequency and trajectory of nocturnal propagating storms.

Urban hydrogeology in Indonesia: A highlight from Jakarta

NASA Astrophysics Data System (ADS)

Lubis, R. F.

2018-02-01

In many cities in the developing countries, groundwater is an important source of public water supply. The interaction between groundwater systems and urban environments has become an urgent challenge for many developing cities in the world, Indonesia included. Contributing factors are, but not limited to, the continuous horizontal and vertical expansion of cities, population growth, climate change, water scarcity and groundwater quality degradation. Jakarta as the capital city of Indonesia becomes a good example to study and implement urban hydrogeology. Urban hydrogeology is a science for investigating groundwater at the hydrological cycle and its change, water regime and quality within the urbanized landscape and zones of its impact. The present paper provides a review of urban groundwater studies in Jakarta in the context of urban water management, advances in hydrogeological investigation, monitoring and modelling since the city was established. The whole study emphasizes the necessity of an integrated urban groundwater management and development supporting hydrogeological techniques for urban areas.

Perspectives on urban conditions and population health.

PubMed

Vlahov, David; Galea, Sandro; Gibble, Emily; Freudenberg, Nicholas

2005-01-01

The majority of the world's population will live in cities in the next few years and the pace of urbanization worldwide will continue to accelerate over the coming decades. While the number of megacities is projected to increase, the largest population growth is expected to be in cities of less than one million people. Such a dramatic demographic shift can be expected to have an impact on population health. Although there has been historic interest in how city living affects health, a cogent framework that enables systematic study of urban health across time and place has yet to emerge. Four alternate but complementary approaches to the study of urban health today are presented (urban health penalty, urban health advantage, urban sprawl, and an integrative urban conditions model) followed by three key questions that may help guide the study and practice of urban health in coming decades.

Has climate change driven urbanization in Africa?

PubMed

Henderson, J Vernon; Storeygard, Adam; Deichmann, Uwe

2017-01-01

This paper documents strong but differentiated links between climate and urbanization in large panels of districts and cities in Sub-Saharan Africa, which has dried substantially in the past fifty years. The key dimension of heterogeneity is whether cities are likely to have manufacturing for export outside their regions, as opposed to being exclusively market towns providing local services to agricultural hinterlands. In regions where cities are likely to be manufacturing centers (25% of our sample), drier conditions increase urbanization and total urban incomes. There, urban migration provides an "escape" from negative agricultural moisture shocks. However, in the remaining market towns (75% of our sample), cities just service agriculture. Reduced farm incomes from negative shocks reduce demand for urban services and derived demand for urban labor. There, drying has little impact on urbanization or total urban incomes. Lack of structural transformation in Africa inhibits a better response to climate change.

Measuring urban sprawl in China by night time light images

NASA Astrophysics Data System (ADS)

Liu, Lu; Tang, Lin

2017-01-01

In the process of urbanization, a phenomenon called “urban sprawl” usually occurs. This phenomenon may exaggerated the negative effects of urbanization on environment, public and social health, energy efficiency, and maintenance of farmland. Therefore, the understanding of this phenomenon is urgently required for us to achieve sustainable development. This study proposed a group of night time lights (NTL) indicators of urban sprawl, which intend to use the distribution of lightness to quantify urban sprawl. These measures are proved to be efficient in describing urban sprawl. In addition, they are consistent and easy calculating, making comparison analysis easy to be done. These indicators are used to study urban sprawl in China during the year 2000 to 2010, the results show that in the last ten years, metropolitan areas in the northern part of China have undergone a more sprawl-like urban growth compared with other parts of China.

Has climate change driven urbanization in Africa?

PubMed Central

Henderson, J. Vernon; Storeygard, Adam; Deichmann, Uwe

2017-01-01

This paper documents strong but differentiated links between climate and urbanization in large panels of districts and cities in Sub-Saharan Africa, which has dried substantially in the past fifty years. The key dimension of heterogeneity is whether cities are likely to have manufacturing for export outside their regions, as opposed to being exclusively market towns providing local services to agricultural hinterlands. In regions where cities are likely to be manufacturing centers (25% of our sample), drier conditions increase urbanization and total urban incomes. There, urban migration provides an “escape” from negative agricultural moisture shocks. However, in the remaining market towns (75% of our sample), cities just service agriculture. Reduced farm incomes from negative shocks reduce demand for urban services and derived demand for urban labor. There, drying has little impact on urbanization or total urban incomes. Lack of structural transformation in Africa inhibits a better response to climate change. PMID:28458445

Urban Spatial Ecological Performance Based on the Data of Remote Sensing of Guyuan

NASA Astrophysics Data System (ADS)

Ren, X.-J.; Chen, X.-J.; Ma, Q.

2018-04-01

The evolution analysis of urban landuse and spatial ecological performance are necessary and useful to recognizing the stage of urban development and revealing the regularity and connotation of urban spatial expansion. Moreover, it lies in the core that should be exmined in the urban sustainable development. In this paper, detailed information has been acquired from the high-resolution satellite imageries of Guyuan, China case study. With the support of GIS, the land-use mapping information and the land cover changes are analyzed, and the process of urban spatial ecological performance evolution by the hierarchical methodology is explored. Results demonstrate that in the past 11 years, the urban spatial ecological performance show an improved process with the dramatic landcover change in Guyuan. Firstly, the landuse structure of Guyuan changes significantly and shows an obvious stage characteristic. Secondly, the urban ecological performance of Guyuan continues to be optimized over the 11 years. Thirdly, the findings suggest that a dynamic monitoring mechanism of urban land use based on high-resolution remote sensing data should be established in urban development, and the rational development of urban land use should be guided by the spatial ecological performance as the basic value orientation.

Detecting urban warming signals in climate records

NASA Astrophysics Data System (ADS)

He, Yuting; Jia, Gensuo; Hu, Yonghong; Zhou, Zijiang

2013-07-01

Determining whether air temperatures recorded at meteorological stations have been contaminated by the urbanization process is still a controversial issue at the global scale. With support of historical remote sensing data, this study examined the impacts of urban expansion on the trends of air temperature at 69 meteorological stations in Beijing, Tianjin, and Hebei Province over the last three decades. There were significant positive relations between the two factors at all stations. Stronger warming was detected at the meteorological stations that experienced greater urbanization, i.e., those with a higher urbanization rate. While the total urban area affects the absolute temperature values, the change of the urban area (urbanization rate) likely affects the temperature trend. Increases of approximately 10% in urban area around the meteorological stations likely contributed to the 0.13°C rise in air temperature records in addition to regional climate warming. This study also provides a new approach to selecting reference stations based on remotely sensed urban fractions. Generally, the urbanization-induced warming contributed to approximately 44.1% of the overall warming trends in the plain region of study area during the past 30 years, and the regional climate warming was 0.30°C (10 yr)-1 in the last three decades.

Environmental challenges threatening the growth of urban agriculture in the United States.

PubMed

Wortman, Sam E; Lovell, Sarah Taylor

2013-09-01

Urban agriculture, though often difficult to define, is an emerging sector of local food economies in the United States. Although urban and agricultural landscapes are often integrated in countries around the world, the establishment of mid- to large-scale food production in the U.S. urban ecosystem is a relatively new development. Many of the urban agricultural projects in the United States have emerged from social movements and nonprofit organizations focused on urban renewal, education, job training, community development, and sustainability initiatives. Although these social initiatives have traction, critical knowledge gaps exist regarding the science of food production in urban ecosystems. Developing a science-based approach to urban agriculture is essential to the economic and environmental sustainability of the movement. This paper reviews abiotic environmental factors influencing urban cropping systems, including soil contamination and remediation; atmospheric pollutants and altered climatic conditions; and water management, sources, and safety. This review paper seeks to characterize the limited state of the science on urban agricultural systems and identify future research questions most relevant to urban farmers, land-use planners, and environmental consultants. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Urban-Water Harmony model to evaluate the urban water management.

PubMed

Ding, Yifan; Tang, Deshan; Wei, Yuhang; Yin, Sun

2014-01-01

Water resources in many urban areas are under enormous stress due to large-scale urban expansion and population explosion. The decision-makers are often faced with the dilemma of either maintaining high economic growth or protecting water resources and the environment. Simple criteria of water supply and drainage do not reflect the requirement of integrated urban water management. The Urban-Water Harmony (UWH) model is based on the concept of harmony and offers a more integrated approach to urban water management. This model calculates four dimensions, namely urban development, urban water services, water-society coordination, and water environment coordination. And the Analytic Hierarchy Process has been used to determine the indices weights. We applied the UWH model to Beijing, China for an 11-year assessment. Our findings show that, despite the severe stress inherent in rapid development and water shortage, the urban water relationship of Beijing is generally evolving in a positive way. The social-economic factors such as the water recycling technologies contribute a lot to this change. The UWH evaluation can provide a reasonable analysis approach to combine various urban and water indices to produce an integrated and comparable evaluation index. This, in turn, enables more effective water management in decision-making processes.

Urban forests for sustainable urban development

NASA Astrophysics Data System (ADS)

Sundara, Denny M.; Hartono, Djoko M.; Suganda, Emirhadi; Haeruman, S. Herman J.

2017-11-01

This paper explores the development of the urban forest in East Jakarta. By 2030 Jakarta area has a target of 30% green area covering 19,845 hectares, including urban forest covering an area of 4,631 hectares. In 2015, the city forest is only 646 hectares, while the city requires 3,985 hectares of new land Urban forest growth from year to year showed a marked decrease with increasing land area awoke to commercial functions, environmental conditions encourage the development of the city to become unsustainable. This research aims to support sustainable urban development and ecological balance through the revitalization of green areas and urban development. Analytical methods for urban forest area is calculated based on the amount of CO2 that comes from people, vehicles, and industrial. Urban spatial analysis based on satellite image data, using a GIS program is an analysis tool to determine the distribution and growth patterns of green areas. This paper uses a dynamic system model to simulate the conditions of the region against intervention to be performed on potential areas for development of urban forests. The result is a model urban forest area is integrated with a social and economic function to encourage the development of sustainable cities.

A study on the relationship between carbon budget and ecosystem service in urban areas according to urbanization

NASA Astrophysics Data System (ADS)

Lee, S. J.; Lee, W. K.

2017-12-01

The study on the analysis of carbon storage capacity of urban green spaces with increasing urban forest. Modern cities have experienced rapid economic development since Industrial Revolution in the 18th century. The rapid economic growth caused an exponential concentration of population to the cities and decrease of green spaces due to the conversion of forest and agricultural lands to build-up areas with rapid urbanization. As green areas including forests, grasslands, and wetlands provide diverse economic, environmental, and cultural benefits, the decrease of green areas might be a huge loss. Also, the process of urbanization caused pressure on the urban environment more than its natural capacity, which accelerates global climate change. This study tries to see the relations between carbon budget and ecosystem services according to the urbanization. For calculating carbon dynamics, this study used VISIT(Vegetation Integrated Simulator for trace gases) model. And the value that ecosystem provides is explained with the concept of ecosystem service and calculated by InVEST model. Study sites are urban and peri-urban areas in Northeast Asia. From the result of the study, the effect of the urbanization can be understood in regard to carbon storage and ecosystem services.

Receptivity to transformative change in the Dutch urban water management sector.

PubMed

de Graaf, R E; Dahm, R J; Icke, J; Goetgeluk, R W; Jansen, S J T; van de Ven, F H M

2009-01-01

Worldwide, the need for transformative change in urban water management is acknowledged by scientists and policy makers. The effects of climate change and developments such as urbanization, the European Water Framework Directive, and societal concerns about the sustainability of urban water system force the sector to adapt. In The Netherlands, a shift towards integration of spatial planning and water management can be observed. Despite major changes in water management policy and approach, changes in the physical urban water management infrastructure remain limited to incremental solutions and demonstration projects. Policy studies show that institutional factors and professional perceptions are important factors for application of innovations in urban water management. An online survey among Dutch urban water management professionals demonstrates that according to most respondents, optimization of the current system is sufficient to achieve both European and national objectives for sustainable urban water management. The respondents are most concerned with the effects of climate change on urban water systems. In contrast to current policy of the national government, priority factors that should be addressed to achieve a more sustainable urban water system are improving knowledge of local urban water systems, capacity building, developing trust between stakeholders, and improving involvement of elected officials and citizens.

The concentration of disadvantage and the rise of an urban penalty: urban slum prevalence and the social production of health inequalities in the developing countries.

PubMed

Rice, James; Rice, Julie Steinkopf

2009-01-01

Urban slums are proliferating in the developing countries. A corollary of this structural transformation is the increasing recognition of an urban penalty wherein slum populations exhibit notable inequalities in health relative to non-slum urban residents and even rural populations. The built urban environment, in turn, is a crucial context within which the social production of disproportionate morbidity and mortality is enacted. The authors develop this assertion and use bivariate and partial correlation analysis to highlight the association of urban slum prevalence, or proportion of the total population living in urban slum conditions, with indicators of mortality and gender parity, measured at the national level. Data for 99 developing countries show that greater urban slum prevalence is strongly correlated with higher levels of infant, child, and maternal mortality. Further, urban slum prevalence exhibits strong, deleterious correlations with gender parity (measured by the gender development index) and fertility rate, factors that have a crucial direct impact in shaping variant mortality levels. Future research is warranted on the social inequalities in health and illness derived from the expansion of urban slum conditions in the developing countries.

Integrated Urban Flood Analysis considering Optimal Operation of Flood Control Facilities in Urban Drainage Networks

NASA Astrophysics Data System (ADS)

Moon, Y. I.; Kim, M. S.; Choi, J. H.; Yuk, G. M.

2017-12-01

eavy rainfall has become a recent major cause of urban area flooding due to the climate change and urbanization. To prevent property damage along with casualties, a system which can alert and forecast urban flooding must be developed. Optimal performance of reducing flood damage can be expected of urban drainage facilities when operated in smaller rainfall events over extreme ones. Thus, the purpose of this study is to execute: A) flood forecasting system using runoff analysis based on short term rainfall; and B) flood warning system which operates based on the data from pump stations and rainwater storage in urban basins. In result of the analysis, it is shown that urban drainage facilities using short term rainfall forecasting data by radar will be more effective to reduce urban flood damage than using only the inflow data of the facility. Keywords: Heavy Rainfall, Urban Flood, Short-term Rainfall Forecasting, Optimal operating of urban drainage facilities. AcknowledgmentsThis research was supported by a grant (17AWMP-B066744-05) from Advanced Water Management Research Program (AWMP) funded by Ministry of Land, Infrastructure and Transport of Korean government.

Urbanization and Income Inequality in Post-Reform China: A Causal Analysis Based on Time Series Data

PubMed Central

Chen, Guo; Glasmeier, Amy K.; Zhang, Min; Shao, Yang

2016-01-01

This paper investigates the potential causal relationship(s) between China’s urbanization and income inequality since the start of the economic reform. Based on the economic theory of urbanization and income distribution, we analyze the annual time series of China’s urbanization rate and Gini index from 1978 to 2014. The results show that urbanization has an immediate alleviating effect on income inequality, as indicated by the negative relationship between the two time series at the same year (lag = 0). However, urbanization also seems to have a lagged aggravating effect on income inequality, as indicated by positive relationship between urbanization and the Gini index series at lag 1. Although the link between urbanization and income inequality is not surprising, the lagged aggravating effect of urbanization on the Gini index challenges the popular belief that urbanization in post-reform China generally helps reduce income inequality. At deeper levels, our results suggest an urgent need to focus on the social dimension of urbanization as China transitions to the next stage of modernization. Comprehensive social reforms must be prioritized to avoid a long-term economic dichotomy and permanent social segregation. PMID:27433966

Urbanization drives the evolution of parallel clines in plant populations

PubMed Central

Renaudin, Marie; Johnson, Marc T. J.

2016-01-01

Urban ecosystems are an increasingly dominant feature of terrestrial landscapes. While evidence that species can adapt to urban environments is accumulating, the mechanisms through which urbanization imposes natural selection on populations are poorly understood. The identification of adaptive phenotypic changes (i.e. clines) along urbanization gradients would facilitate our understanding of the selective factors driving adaptation in cities. Here, we test for phenotypic clines in urban ecosystems by sampling the frequency of a Mendelian-inherited trait—cyanogenesis—in white clover (Trifolium repens L.) populations along urbanization gradients in four cities. Cyanogenesis protects plants from herbivores, but reduces tolerance to freezing temperatures. We found that the frequency of cyanogenic plants within populations decreased towards the urban centre in three of four cities. A field experiment indicated that spatial variation in herbivory is unlikely to explain these clines. Rather, colder minimum winter ground temperatures in urban areas compared with non-urban areas, caused by reduced snow cover in cities, may select against cyanogenesis. In the city with no cline, high snow cover might protect plants from freezing damage in the city centre. Our study suggests that populations are adapting to urbanization gradients, but regional climatic patterns may ultimately determine whether adaptation occurs. PMID:28003451

Urbanization drives the evolution of parallel clines in plant populations.

PubMed

Thompson, Ken A; Renaudin, Marie; Johnson, Marc T J

2016-12-28

Urban ecosystems are an increasingly dominant feature of terrestrial landscapes. While evidence that species can adapt to urban environments is accumulating, the mechanisms through which urbanization imposes natural selection on populations are poorly understood. The identification of adaptive phenotypic changes (i.e. clines) along urbanization gradients would facilitate our understanding of the selective factors driving adaptation in cities. Here, we test for phenotypic clines in urban ecosystems by sampling the frequency of a Mendelian-inherited trait-cyanogenesis-in white clover (Trifolium repens L.) populations along urbanization gradients in four cities. Cyanogenesis protects plants from herbivores, but reduces tolerance to freezing temperatures. We found that the frequency of cyanogenic plants within populations decreased towards the urban centre in three of four cities. A field experiment indicated that spatial variation in herbivory is unlikely to explain these clines. Rather, colder minimum winter ground temperatures in urban areas compared with non-urban areas, caused by reduced snow cover in cities, may select against cyanogenesis. In the city with no cline, high snow cover might protect plants from freezing damage in the city centre. Our study suggests that populations are adapting to urbanization gradients, but regional climatic patterns may ultimately determine whether adaptation occurs. © 2016 The Author(s).

Urbanization and Income Inequality in Post-Reform China: A Causal Analysis Based on Time Series Data.

PubMed

Chen, Guo; Glasmeier, Amy K; Zhang, Min; Shao, Yang

2016-01-01

This paper investigates the potential causal relationship(s) between China's urbanization and income inequality since the start of the economic reform. Based on the economic theory of urbanization and income distribution, we analyze the annual time series of China's urbanization rate and Gini index from 1978 to 2014. The results show that urbanization has an immediate alleviating effect on income inequality, as indicated by the negative relationship between the two time series at the same year (lag = 0). However, urbanization also seems to have a lagged aggravating effect on income inequality, as indicated by positive relationship between urbanization and the Gini index series at lag 1. Although the link between urbanization and income inequality is not surprising, the lagged aggravating effect of urbanization on the Gini index challenges the popular belief that urbanization in post-reform China generally helps reduce income inequality. At deeper levels, our results suggest an urgent need to focus on the social dimension of urbanization as China transitions to the next stage of modernization. Comprehensive social reforms must be prioritized to avoid a long-term economic dichotomy and permanent social segregation.

Spatiotemporal Analysis of Malaria in Urban Ahmedabad (Gujarat), India: Identification of Hot Spots and Risk Factors for Targeted Intervention

PubMed Central

Parizo, Justin; Sturrock, Hugh J. W.; Dhiman, Ramesh C.; Greenhouse, Bryan

2016-01-01

The world population, especially in developing countries, has experienced a rapid progression of urbanization over the last half century. Urbanization has been accompanied by a rise in cases of urban infectious diseases, such as malaria. The complexity and heterogeneity of the urban environment has made study of specific urban centers vital for urban malaria control programs, whereas more generalizable risk factor identification also remains essential. Ahmedabad city, India, is a large urban center located in the state of Gujarat, which has experienced a significant Plasmodium vivax and Plasmodium falciparum disease burden. Therefore, a targeted analysis of malaria in Ahmedabad city was undertaken to identify spatiotemporal patterns of malaria, risk factors, and methods of predicting future malaria cases. Malaria incidence in Ahmedabad city was found to be spatially heterogeneous, but temporally stable, with high spatial correlation between species. Because of this stability, a prediction method utilizing historic cases from prior years and seasons was used successfully to predict which areas of Ahmedabad city would experience the highest malaria burden and could be used to prospectively target interventions. Finally, spatial analysis showed that normalized difference vegetation index, proximity to water sources, and location within Ahmedabad city relative to the dense urban core were the best predictors of malaria incidence. Because of the heterogeneity of urban environments and urban malaria itself, the study of specific large urban centers is vital to assist in allocating resources and informing future urban planning. PMID:27382081

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools.

PubMed

Seto, Karen C; Güneralp, Burak; Hutyra, Lucy R

2012-10-02

Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass. If current trends in population density continue and all areas with high probabilities of urban expansion undergo change, then by 2030, urban land cover will increase by 1.2 million km(2), nearly tripling the global urban land area circa 2000. This increase would result in considerable loss of habitats in key biodiversity hotspots, with the highest rates of forecasted urban growth to take place in regions that were relatively undisturbed by urban development in 2000: the Eastern Afromontane, the Guinean Forests of West Africa, and the Western Ghats and Sri Lanka hotspots. Within the pan-tropics, loss in vegetation biomass from areas with high probability of urban expansion is estimated to be 1.38 PgC (0.05 PgC yr(-1)), equal to ∼5% of emissions from tropical deforestation and land-use change. Although urbanization is often considered a local issue, the aggregate global impacts of projected urban expansion will require significant policy changes to affect future growth trajectories to minimize global biodiversity and vegetation carbon losses.

Effects of income and urban form on urban NO2: global evidence from satellites.

PubMed

Bechle, Matthew J; Millet, Dylan B; Marshall, Julian D

2011-06-01

Urban air pollution is among the top 15 causes of death and disease worldwide, and a problem of growing importance with a majority of the global population living in cities. A important question for sustainable development is to what extent urban design can improve or degrade the environment and public health. We investigate relationships between satellite-derived estimates of nitrogen dioxide concentration (NO(2), a key component of urban air pollution) and urban form for 83 cities globally. We find a parsimonious yet powerful relationship (model R(2) = 0.63), using as predictors population, income, urban contiguity, and meteorology. Cities with highly contiguous built-up areas have, on average, lower urban NO(2) concentrations (a one standard deviation increase in contiguity is associated with a 24% decrease in average NO(2) concentration). More-populous cities tend to have worse air quality, but the increase in NO(2) associated with a population increase of 10% may be offset by a moderate increase (4%) in urban contiguity. Urban circularity ("compactness") is not a statistically significant predictor of NO(2) concentration. Although many factors contribute to urban air pollution, our findings suggest that antileapfrogging policies may improve air quality. We find that urban NO(2) levels vary nonlinearly with income (Gross Domestic Product), following an "environmental Kuznets curve"; we estimate that if high-income countries followed urban pollution-per-income trends observed for low-income countries, NO(2) concentrations in high-income cities would be ∼10× larger than observed levels.

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools

PubMed Central

Seto, Karen C.; Güneralp, Burak; Hutyra, Lucy R.

2012-01-01

Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass. If current trends in population density continue and all areas with high probabilities of urban expansion undergo change, then by 2030, urban land cover will increase by 1.2 million km2, nearly tripling the global urban land area circa 2000. This increase would result in considerable loss of habitats in key biodiversity hotspots, with the highest rates of forecasted urban growth to take place in regions that were relatively undisturbed by urban development in 2000: the Eastern Afromontane, the Guinean Forests of West Africa, and the Western Ghats and Sri Lanka hotspots. Within the pan-tropics, loss in vegetation biomass from areas with high probability of urban expansion is estimated to be 1.38 PgC (0.05 PgC yr−1), equal to ∼5% of emissions from tropical deforestation and land-use change. Although urbanization is often considered a local issue, the aggregate global impacts of projected urban expansion will require significant policy changes to affect future growth trajectories to minimize global biodiversity and vegetation carbon losses. PMID:22988086

Nested high-resolution modeling of the impact of urbanization on regional climate in three vast urban agglomerations in China

NASA Astrophysics Data System (ADS)

Wang, Jun; Feng, Jinming; Yan, Zhongwei; Hu, Yonghong; Jia, Gensuo

2012-11-01

In this paper, the Weather Research and Forecasting Model, coupled to the Urban Canopy Model, is employed to simulate the impact of urbanization on the regional climate over three vast city agglomerations in China. Based on high-resolution land use and land cover data, two scenarios are designed to represent the nonurban and current urban land use distributions. By comparing the results of two nested, high-resolution numerical experiments, the spatial and temporal changes on surface air temperature, heat stress index, surface energy budget, and precipitation due to urbanization are analyzed and quantified. Urban expansion increases the surface air temperature in urban areas by about 1°C, and this climatic forcing of urbanization on temperature is more pronounced in summer and nighttime than other seasons and daytime. The heat stress intensity, which reflects the combined effects of temperature and humidity, is enhanced by about 0.5 units in urban areas. The regional incoming solar radiation increases after urban expansion, which may be caused by the reduction of cloud fraction. The increased temperature and roughness of the urban surface lead to enhanced convergence. Meanwhile, the planetary boundary layer is deepened, and water vapor is mixed more evenly in the lower atmosphere. The deficit of water vapor leads to less convective available potential energy and more convective inhibition energy. Finally, these combined effects may reduce the rainfall amount over urban areas, mainly in summer, and change the regional precipitation pattern to a certain extent.

The NSF-RCN Urban Heat Island Network

NASA Astrophysics Data System (ADS)

Twine, T. E.; Snyder, P. K.; Hamilton, P.; Shepherd, M.; Stone, B., Jr.

2015-12-01

In much of the world cities are warming at twice the rate of outlying rural areas. The frequency of urban heat waves is projected to increase with climate change through the 21st century. Addressing the economic, environmental, and human costs of urban heat islands requires a better understanding of their behavior from many disciplinary perspectives. The goal of this four-year Urban Heat Island Network is to (1) bring together scientists studying the causes and impacts of urban warming, (2) advance multidisciplinary understanding of urban heat islands, (3) examine how they can be ameliorated through engineering and design practices, and (4) share these new insights with a wide array of stakeholders responsible for managing urban warming to reduce their health, economic, and environmental impacts. The NSF-RCN Urban Heat Island Network involves atmospheric scientists, engineers, architects, landscape designers, urban planners, public health experts, and education and outreach experts, who will share knowledge, evaluate research directions, and communicate knowledge and research recommendations to the larger research community as well as stakeholders engaged in developing strategies to adapt to and mitigate urban warming. The first Urban Climate Institute was held in Saint Paul, MN in July 2013 and focused on the characteristics of urban heat islands. Scientists engaged with local practitioners to improve communication pathways surrounding issues of understanding, adapting to, and mitigating urban warming. The second Urban Climate Institute was held in Atlanta, Georgia in July 2014 and focused on urban warming and public health. The third Urban Climate Institute was held in Athens, GA in July 2015 and focused on urban warming and the role of the built environment. Scientists and practitioners discussed strategies for mitigation and adaptation. Evaluation experts at the Science Museum of Minnesota have extensively evaluated the Institutes to inform other research coordination networks and to identify effective ways that researchers and practitioners can share knowledge and communicate more effectively. A final Institute is planned for July of 2016 in Saint Paul, MN. This institute will focus on synthesizing findings from the first three workshops and discuss education and outreach efforts.

A Comparison of Natural and Urban Characteristics and the Development of Urban Intensity Indices Across Six Geographic Settings

USGS Publications Warehouse

Falcone, James A.; Stewart, Jana; Sobieszczyk, Steven; Dupree, Jean; McMahon, Gerard; Buell, Gary

2007-01-01

As part of the U.S. Geological Survey National Water-Quality Assessment Program, the effects of urbanization on stream ecosystems have been intensively investigated in six metropolitan areas in the United States. Approximately 30 watersheds in each area, ranging in size from 4 to 560 square kilometers (median is 50 square kilometers), and spanning a development gradient from very low to very high urbanization, were examined near Atlanta, Georgia; Raleigh, North Carolina; Denver, Colorado; Dallas-Fort Worth, Texas; Portland, Oregon; and Milwaukee-Green Bay, Wisconsin. These six studies are a continuation of three previous studies in Boston, Massachusetts; Birmingham, Alabama; and Salt Lake City, Utah. In each study, geographic information system data for approximately 300 variables were assembled to (a) characterize the environmental settings of the areas and (b) establish a consistent multimetric urban intensity index based on locally important land-cover, infrastructure, and socioeconomic variables. This paper describes the key features of urbanization and the urban intensity index for the study watersheds within each area, how they differ across study areas, and the relation between the environmental setting and the characteristics of urbanization. A number of features of urbanization were identified that correlated very strongly to population density in every study area. Of these, road density had the least variability across diverse geographic settings and most closely matched the multimetric nature of the urban intensity index. A common urban intensity index was derived that ranks watersheds across all six study areas. Differences in local natural settings and urban geography were challenging in (a) identifying consistent urban gradients in individual study areas and (b) creating a common urban intensity index that matched the site scores of the local urban intensity index in all areas. It is intended that the descriptions of the similarities and differences in urbanization and environmental settings across these study areas will provide a foundation for understanding and interpreting the effects of urbanization on stream ecosystems in the studies being conducted as part of the National Water-Quality Assessment Program.

High resolution modeling of a small urban catchment

NASA Astrophysics Data System (ADS)

Skouri-Plakali, Ilektra; Ichiba, Abdellah; Gires, Auguste; Tchiguirinskaia, Ioulia; Schertzer, Daniel

2016-04-01

Flooding is one of the most complex issues that urban environments have to deal with. In France, flooding remains the first natural risk with 72% of decrees state of natural disaster issued between October 1982 and mid-November 2014. Flooding is a result of meteorological extremes that are usually aggravated by the hydrological behavior of urban catchments and human factors. The continuing urbanization process is indeed changing the whole urban water cycle by limiting the infiltration and promoting runoff. Urban environments are very complex systems due to their extreme variability, the interference between human activities and natural processes but also the effect of the ongoing urbanization process that changes the landscape and hardly influences their hydrologic behavior. Moreover, many recent works highlight the need to simulate all urban water processes at their specific temporal and spatial scales. However, considering urban catchments heterogeneity still challenging for urban hydrology, even after advances noticed in term of high-resolution data collection and computational resources. This issue is more to be related to the architecture of urban models being used and how far these models are ready to take into account the extreme variability of urban catchments. In this work, high spatio-temporal resolution modeling is performed for a small and well-equipped urban catchment. The aim of this work is to identify urban modeling needs in terms of spatial and temporal resolution especially for a very small urban area (3.7 ha urban catchment located in the Perreux-sur-Marne city at the southeast of Paris) MultiHydro model was selected to carry out this work, it is a physical based and fully distributed model that interacts four existing modules each of them representing a portion of the water cycle in urban environments. MultiHydro was implemented at 10m, 5m and 2m resolution. Simulations were performed at different spatio-temporal resolutions and analyzed with respect to real flow measurements. First Results coming out show improvements obtained in terms of the model performance at high spatio-temporal resolution.

Effects of urbanization on stream ecosystems along an agriculture-to-urban land-use gradient, Milwaukee to Green Bay, Wisconsin, 2003-2004

USGS Publications Warehouse

Richards, Kevin D.; Scudder, Barbara C.; Fitzpatrick, Faith A.; Steuer, Jeffery J.; Bell, Amanda H.; Peppler, Marie C.; Stewart, Jana S.; Harris, Mitchell A.

2010-01-01

In 2003 and 2004, 30 streams near Milwaukee and Green Bay, Wisconsin, were part of a national study by the U.S. Geological Survey to assess urbanization effects on physical, chemical, and biological characteristics along an agriculture-to-urban land-use gradient. A geographic information system was used to characterize natural landscape features that define the environmental setting and the degree of urbanization within each stream watershed. A combination of land cover, socioeconomic, and infrastructure variables were integrated into a multi-metric urban intensity index, scaled from 0 to 100, and assigned to each stream site to identify a gradient of urbanization within relatively homogeneous environmental settings. The 35 variables used to develop the final urban intensity index characterized the degree of urbanization and included road infrastructure (road area and road traffic index), 100-meter riparian land cover (percentage of impervious surface, shrubland, and agriculture), watershed land cover (percentage of impervious surface, developed/urban land, shrubland, and agriculture), and 26 socioeconomic variables (U.S. Census Bureau, 2001). Characteristics examined as part of this study included: habitat, hydrology, stream temperature, water chemistry (chloride, sulfate, nutrients, dissolved and particulate organic and inorganic carbon, pesticides, and suspended sediment), benthic algae, benthic invertebrates, and fish. Semipermeable membrane devices (SPMDs) were used to assess the potential for bioconcentration of hydrophobic organic contaminants (specifically polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine and pyrethroid insecticides) in biological membranes, such as the gills of fish. Physical habitat measurements reflective of channel enlargement, including bankfull channel size and bank erosion, increased with increasing urbanization within the watershed. In this study, percentage of riffles and streambed substrate size were more strongly related to local geologic setting, slope, watershed topography, and river-engineering practices than to urbanization. Historical local river-engineering features such as channelization, bank stabilization, and grade controls may have confounded relations among habitat characteristics and urbanization. A number of hydrologic-condition metrics (including flashiness and duration of high flow during pre- or post-ice periods) showed strong relations to the urban intensity index. Hydrologic-condition metrics cannot be used alone to predict habitat or geomorphic change. Chloride and SPMD measures of potential toxicity and polycyclic aromatic hydrocarbon concentrations showed the strongest positive correlations to urbanization including increases in road infrastructure, percentage of impervious surface in the watershed, urban land cover, and land-distribution related to urban land cover. This suggests that automobiles and the infrastructure required to support automobiles are a significant source of these compounds in this study area. Chloride in spring and summer showed a significant positive correlation with the urban intensity index; concentrations increased with increasing road infrastructure, urban land cover, and a number of landscape variables related to urbanization. Spring concentrations of sulfate, prometon, and diazinon correlated to fewer urban characteristics than chloride, including increases in road infrastructure, percentage of impervious surface, and urban land cover. Changes in biological communities correlated to the urban intensity index or individual urban-associated variables. Decreased percentages of pollution-sensitive diatoms and diatoms requiring high dissolved-oxygen saturation correlated to increases in the percentage of developed urban land, total impervious surface, stream flashiness, population density, road-area density, and decreases in the percentage of wetland in the watershed. Invertebrate taxa richness and Coleop

Bioindication in Urban Soils in Switzerland

NASA Astrophysics Data System (ADS)

Amossé, J.; Le Bayon, C.; Mitchell, E. A. D.; Gobat, J. M.

2012-04-01

Urban development leads to profound changes in ecosystem structure (e.g. biodiversity) and functioning (e.g. ecosystem services). While above-ground diversity is reasonably well studied much less is known about soil diversity, soil processes and more generally soil health in urban settings. Soil invertebrates are key actors of soil processes at different spatial and temporal scales and provide essential ecosystem services. These functions may be even more vital in stressed environments such as urban ecosystems. Despite the general recognition of the importance of soil organisms in ecosystems, soil trophic food webs are still poorly known and this is especially the case in urban settings. As urban soils are characterised by high fragmentation and stress (e.g. drought, pollution) the structure and functioning of soil communities is likely to be markedly different from that of natural soils. It is for example unclear if earthworms, whose roles in organic matter transformation and soil structuration is well documented in natural and semi-natural soils, are also widespread and active in urban soils. Bioindication is a powerful tool to assess the quality of the environment. It is complementary to classical physicochemical soil analysis or can be used as sole diagnostic tool in cases where these analyses cannot be performed. However little is known about the potential use of bioindicators in urban settings and especially it is unclear if methods developped in agriculture can be applied to urban soils. The development of reliable methods for assessing the quality of urban soils has been identified as a priority for policy making and urban management in Switzerland, a high-urbanized country. We therefore initiated a research project (Bioindication in Urban Soil - BUS). The project is organised around four parts: (i) typology of urban soils in a study Region (Neuchâtel), (ii) sampling of soil fauna and analysis of soil physicochemical properties, (iii) comparison of the functionality of urban soils and alluvial soils, used as a natural reference because of their regular physical perturbation by flooding and associated erosion/sedimentation, (iv) evaluation of soil bioindicators (e.g. earthworm, enchytraeid and testate amoebae) for urban soils. The application objective of my research is to introduce bioindicators and their limit values for the future revision of the legal Ordonnance on soils (OSol), and to develop guidelines to improve or to build urban soils with the aim of reaching a sustainable urban ecosystem development.

The need for a national urbanization policy in Nepal.

PubMed

Ertur, O

1994-09-01

There is a need for a national urbanization policy in Nepal as a means of redressing regional disparities in development between the hills, the Kathmandu Valley, and the Terai versus rural and urban areas. A settlement system would complement urban and rural development and reduce dependency on India. An urbanization policy would be both systematic and guided by public and private investment in existing urban and rural settlements. Regional investment in development would contribute to commercialization and agricultural industrialization (development and linkage of market towns and service centers, strengthening of basic infrastructure and land use patterns, strengthening of urban areas around transportation centers, promoting nonfarm employment opportunities, establishing strong financial and technical institutions in middle-sized cities, and strengthening municipalities' mobilization of local resources and financing). Nepal has been one of the least developed countries in its region. The agricultural economy provides economic support for 80% of total population. In 1991, density was 130 person per sq. km. 9% of the total population live in urban areas, but the rate of urban growth is the highest among South Asian Regional Cooperation countries (7.3% in Nepal compared to 6.1% in Bangladesh and 3.7% in India). Rural markets and towns are rapidly becoming urbanized but without basic infrastructure. The spatial component of urbanization must be emphasized. Total population increased in the Terai from 37% in 1971 to 47% in 1991, which increased population density by 31% but not cultivation. Harsh physical conditions in mountainous regions and lack of cultivable land are push factors. Pull factors are employment opportunities in emerging urban centers and the availability of agricultural employment in the Terai. Movement to lowlands is enhanced by the eradication of malaria. 53% of the urban population is in the Terai in 1991, which also has 65% of cultivable land, 35% of roads, and 63% of industry. Urban settlements increased from 10 in 1951 to 33 in 1987 and 36 in 1991. In the Terai, the increases are from five to 21 urban centers. The central and eastern region have experienced faster urban growth than the other three regions. Kathmandu is the most populated urban center followed by Biratnagar, Pokhara, and Birganj. Government ministries are ill-equipped to handle the technical and manpower needs in the process of urbanization.

Reassessment of urbanization effect on surface air temperature trends at an urban station of North China

NASA Astrophysics Data System (ADS)

Bian, Tao; Ren, Guoyu

2017-11-01

Based on a homogenized data set of monthly mean temperature, minimum temperature, and maximum temperature at Shijiazhuang City Meteorological Station (Shijiazhuang station) and four rural meteorological stations selected applying a more sophisticated methodology, we reanalyzed the urbanization effects on annual, seasonal, and monthly mean surface air temperature (SAT) trends for updated time period 1960-2012 at the typical urban station in North China. The results showed that (1) urbanization effects on the long-term trends of annual mean SAT, minimum SAT, and diurnal temperature range (DTR) in the last 53 years reached 0.25, 0.47, and - 0.50 °C/decade, respectively, all statistically significant at the 0.001 confidence level, with the contributions from urbanization effects to the overall long-term trends reaching 67.8, 78.6, and 100%, respectively; (2) the urbanization effects on the trends of seasonal mean SAT, minimum SAT, and DTR were also large and statistically highly significant. Except for November and December, the urbanization effects on monthly mean SAT, minimum SAT, and DTR were also all statistically significant at the 0.05 confidence level; and (3) the annual, seasonal, and monthly mean maximum SAT series at the urban station registered a generally weaker and non-significant urbanization effect. The updated analysis evidenced that our previous work for this same urban station had underestimated the urbanization effect and its contribution to the overall changes in the SAT series. Many similar urban stations were being included in the current national and regional SAT data sets, and the results of this paper further indicated the importance and urgency for paying more attention to the urbanization bias in the monitoring and detection of global and regional SAT change based on the data sets.

Assessing the resilience of urban areas to traffic-related air pollution: Application in Greater Paris.

PubMed

Cariolet, Jean-Marie; Colombert, Morgane; Vuillet, Marc; Diab, Youssef

2018-02-15

Recent studies report that outdoor air pollution will become the main environmental cause of premature death over the next few decades (OECD, 2012; WHO, 2014; World Bank, 2016). Cities are considered hot spots and urban populations are particularly exposed. There is therefore an urgent need to adapt urban systems and urban design to tackle this issue. While most European cities have introduced measures to reduce emissions, action is still required to reduce concentrations and exposure, and a holistic approach to urban design is badly needed. The concept of urban resilience, defined by Holling (1987) as the ability of a city to absorb a disturbance while maintaining its functions and structures, may offer a new paradigm for tackling urban air pollution. We propose to adapt the concept of urban resilience to outdoor air pollution. A method has been developed to assess the resilience of an urban area to outdoor air pollution. Three "resilience capacities" have been identified: the capacity of an urban area to decrease air pollution emissions, the capacity to decrease concentrations and the capacity to decrease exposure. The calculation is based on the analysis of urban design, defined as the pattern of buildings as well as the structural elements that define an urban area (urban morphology; transport network, services and land use). For each resilience capacity, indicators are calculated using a Geographic Information System (GIS) and a grid-based approach. This method has been implemented in the Greater Paris area within a 500m grid-cell system. Greater Paris is one of the densest urban areas in Europe and experiences high air pollution levels. The proposed "quick scan" method helps to localize areas where specific action is needed. Copyright © 2017 Elsevier B.V. All rights reserved.

Landscape urbanization and economic growth in China: positive feedbacks and sustainability dilemmas.

PubMed

Bai, Xuemei; Chen, Jing; Shi, Peijun

2012-01-03

Accelerating urbanization has been viewed as an important instrument for economic development and reducing regional income disparity in some developing countries, including China. Recent studies (Bloom et al. 2008) indicate that demographic urbanization level has no causal effect on economic growth. However, due to the varying and changing definition of urban population, the use of demographic indicators as a sole representing indicator for urbanization might be misleading. Here, we re-examine the causal relationship between urbanization and economic growth in Chinese cities and provinces in recent decades, using built-up areas as a landscape urbanization indicator. Our analysis shows that (1) larger cities, both in terms of population size and built-up area, and richer cities tend to gain more income, have larger built-up area expansion, and attract more population, than poorer cities or smaller cities; and (2) that there is a long-term bidirectional causality between urban built-up area expansion and GDP per capita at both city and provincial level, and a short-term bidirectional causality at provincial level, revealing a positive feedback between landscape urbanization and urban and regional economic growth in China. Our results suggest that urbanization, if measured by a landscape indicator, does have causal effect on economic growth in China, both within the city and with spillover effect to the region, and that urban land expansion is not only the consequences of economic growth in cities, but also drivers of such growth. The results also suggest that under its current economic growth model, it might be difficult for China to control urban expansion without sacrificing economic growth, and China's policy to stop the loss of agricultural land, for food security, might be challenged by its policy to promote economic growth through urbanization.

Aquatic assemblages of the highly urbanized Santa Ana River Basin, California

USGS Publications Warehouse

Brown, Larry R.; Burton, Carmen; Belitz, Kenneth

2005-01-01

We assessed the structure of periphyton, benthic macroinvertebrate, and fish assemblages and their associations with environmental variables at 17 sites on streams of the highly urbanized Santa Ana River basin in Southern California. All assemblages exhibited strong differences between highly urbanized sites in the valley and the least-impacted sites at the transition between the valley and undeveloped mountains. Results within the urbanized area differed among taxa. Periphyton assemblages were dominated by diatoms (>75% of total taxa). Periphyton assemblages within the urbanized area were not associated with any of the measured environmental variables, suggesting that structure of urban periphyton assemblages might be highly dependent on colonization dynamics. The number of Ephemeroptera, Trichoptera, and Plecoptera (EPT) taxa included in macroinvertebrate assemblages ranged from 0 to 6 at urbanized sites. Benthic macroinvertebrate assemblages had significant correlations with several environmental variables within the urban area, suggesting that stream size and permanence were important determinants of distribution among the species able to survive conditions in urban streams. Only 4 of 16 fish species collected were native to the drainage. Fish assemblages of urbanized sites included two native species, arroyo chub Gila orcuttii and Santa Ana sucker Catostomus santaanae, at sites that were intermediate in coefficient of variation of bank-full width, depth, bed substrate, and water temperature. Alien species dominated urbanized sites with lesser or greater values for these variables. These results suggest that urban streams can be structured to enhance populations of native fishes. Continued study of urban streams in the Santa Ana River basin and elsewhere will contribute to the basic understanding of ecological principles and help preserve the maximum ecological value of streams in highly urbanized areas.

Challenging urban health: towards an improved local government response to migration, informal settlements, and HIV in Johannesburg, South Africa

PubMed Central

Vearey, Joanna

2011-01-01

This article is a review of the PhD thesis undertaken by Joanna Vearey that explores local government responses to the urban health challenges of migration, informal settlements, and HIV in Johannesburg, South Africa. Urbanisation in South Africa is a result of natural urban growth and (to a lesser extent) in-migration from within the country and across borders. This has led to the development of informal settlements within and on the periphery of urban areas. The highest HIV prevalence nationally is found within urban informal settlements. South African local government has a ‘developmental mandate’ that calls for government to work with citizens to develop sustainable interventions to address their social, economic, and material needs. Through a mixed-methods approach, four studies were undertaken within inner-city Johannesburg and a peripheral urban informal settlement. Two cross-sectional surveys – one at a household level and one with migrant antiretroviral clients – were supplemented with semi-structured interviews with multiple stakeholders involved with urban health and HIV in Johannesburg, and participatory photography and film projects undertaken with urban migrant communities. The findings show that local government requires support in developing and implementing appropriate intersectoral responses to address urban health. Existing urban health frameworks do not deal adequately with the complex health and development challenges identified; it is essential that urban public health practitioners and other development professionals in South Africa engage with the complexities of the urban environment. A revised, participatory approach to urban health – ‘concept mapping’ – is suggested which requires a recommitment to intersectoral action, ‘healthy urban governance’ and public health advocacy. PMID:21686331

Future Urban Climate Projection in A Tropical Megacity Based on Global and Regional Scenarios

NASA Astrophysics Data System (ADS)

Darmanto, N. S.; Varquez, A. C. G.; Kanda, M.

2017-12-01

Cities in Asian developing countries experience rapid transformation in urban morphology and energy consumption, which correspondingly affects urban climate. Weather Research and Forecasting (WRF) Model coupled with improved single-layer urban canopy model incorporating realistic distribution of urban parameters and anthropogenic heat emission (AHE) in the tropic Jakarta Greater Area was conducted. Simulation was conducted during the dry months from 2006 to 2015 and agreed well with point and satellite observation. The same technology coupled with pseudo global warming (PGW) method based on representative concentration pathways (RCP) scenario 2.6 and 8.5 was conducted to produce futuristic climate condition in 2050. Projected urban morphology and AHE in 2050s were constructed using regional urban growing model with shared socioeconomic pathways (SSP) among its inputs. Compact future urban configuration, based on SSP1, was coupled to RCP2.6. Unrestrained future urban configuration, based on SSP3, was coupled to RCP8.5. Results show that background warming from RCP 2.6 and 8.5 will increase background temperature by 0.55°C and 1.2°C throughout the region, respectively. Future projection of urban sprawl results to an additional 0.3°C and 0.5°C increase on average, with maximum increase of 1.1°C and 1.3°C due to urban effect for RCP2.6/compact and RCP8.5/unrestrained, respectively. Higher moisture content in urban area is indicated in the future due to higher evaporation. Change in urban roughness is likely affect slower wind velocity in urban area and sea breeze front inland penetration the future compare with current condition. Acknowledgement: This research was supported by the Environment Research and Technology Development Fund (S-14) of the Ministry of the Environment, Japan.

Street Level Hydrology: An Urban Application of the WRF-Hydro Framework in Denver, Colorado

NASA Astrophysics Data System (ADS)

Read, L.; Hogue, T. S.; Salas, F. R.; Gochis, D.

2015-12-01

Urban flood modeling at the watershed scale carries unique challenges in routing complexity, data resolution, social and political issues, and land surface - infrastructure interactions. The ability to accurately trace and predict the flow of water through the urban landscape enables better emergency response management, floodplain mapping, and data for future urban infrastructure planning and development. These services are of growing importance as urban population is expected to continue increasing by 1.84% per year for the next 25 years, increasing the vulnerability of urban regions to damages and loss of life from floods. Although a range of watershed-scale models have been applied in specific urban areas to examine these issues, there is a trend towards national scale hydrologic modeling enabled by supercomputing resources to understand larger system-wide hydrologic impacts and feedbacks. As such it is important to address how urban landscapes can be represented in large scale modeling processes. The current project investigates how coupling terrain and infrastructure routing can improve flow prediction and flooding events over the urban landscape. We utilize the WRF-Hydro modeling framework and a high-resolution terrain routing grid with the goal of compiling standard data needs necessary for fine scale urban modeling and dynamic flood forecasting in the urban setting. The city of Denver is selected as a case study, as it has experienced several large flooding events in the last five years and has an urban annual population growth rate of 1.5%, one of the highest in the U.S. Our work highlights the hydro-informatic challenges associated with linking channel networks and drainage infrastructure in an urban area using the WRF-Hydro modeling framework and high resolution urban models for short-term flood prediction.

Perthes' disease of the hip: socioeconomic inequalities and the urban environment.

PubMed

Perry, Daniel C; Bruce, Colin E; Pope, Daniel; Dangerfield, Peter; Platt, Mary Jane; Hall, Andrew J

2012-12-01

Perthes' disease is a puzzling childhood hip disorder for which the aetiology is unknown. It is known to be associated with socioeconomic deprivation. Urban environments have also been implicated as a risk factor, however socioeconomic deprivation often occurs within urban environments and it is unclear if this association is the result of confounding. The objective of the current work was to gain a greater understanding of the influence of the urban/rural environment in Perthes' disease. This was a descriptive observational study using the Scottish Morbidity Record, based in Scotland, UK using data from 2000-2010. A total of 443 patients with a discharge diagnosis of Perthes' disease were included. Socioeconomic deprivation was determined using the Scottish Index of Multiple Deprivation, and exposure to the 'urban environment' was recorded based on the Scottish Urban-Rural Classification. There was a strong association with socioeconomic deprivation, with rates among the most deprived quintile more than twice those of the most affluent (RR 2.1 (95% CI 1.5 to 2.9)). Urban areas had a greater rate of Perthes' disease discharges (RR 1.8 (95% CI 1.1 to 3.2)), though this was a reflection of greater deprivation in urban areas. Stratification for socioeconomic deprivation revealed similar discharge rates in urban and rural environments, suggesting that the aetiological determinants were not independently associated with urban environments. The occurrence of Perthes' disease within urban environments is high, yet this appears to be a reflection of higher socioeconomic deprivation exposure. Disease rates appear equivalent in similarly deprived urban and non-urban areas, suggesting that the determinant is not a consequence of the urban environment.

Increasing of Urban Radiation due to Climate Change and Reduction Strategy using Vegetation

NASA Astrophysics Data System (ADS)

Park, C.; Lee, D.; Heo, H. K.; Ahn, S.

2017-12-01

Urban Heat Island (UHI) which means urban air temperature is higher than suburban area is one of the most important environmental issues in Urban. High density of buildings and high ratio of impervious surfaces increases the radiation fluxes in urban canopy. Furthermore, climate change is expected to make UHI even more seriously in the future. Increased irradiation and air temperature cause high amount of short wave and long wave radiation, respectively. This increases net radiation negatively affects heat condition of pedestrian. UHI threatens citizen's health by increasing violence and heat related diseases. For this reason, understanding how much urban radiation will increase in the future, and exploring radiation reduction strategies is important for reducing UHI. In this research, we aim to reveal how the radiation flux in the urban canyon will change as the climate change and determine how much of urban vegetation will be needed to cover this degradation. The study area is a commercial district in Seoul where highly populated area. Due to the high density of buildings and lack of urban vegetation, this area has a poor thermal condition in summer. In this research, we simulate the radiation flux on the ground using multi-layer urban canopy model. Unlike conventionally used urban canopy model to simulate radiation transfer using vertically single layer, the multi-layer model we used here, enables to consider the vertical heterogeneous of buildings and urban vegetation. As a result, net radiation of urban ground will be increase 2.1 W/m² in the 2050s and 2.7 W/m² in the 2100s. And to prevent the increase of radiation, it is revealed that the urban vegetation should by increased by 10%. This research will be valuable in establishing greening planning as a strategy to reduce UHI effect.

Thermal signatures of urban land cover types: High-resolution thermal infrared remote sensing of urban heat island in Huntsville, AL

NASA Technical Reports Server (NTRS)

Lo, Chor Pang

1996-01-01

The main objective of this research is to apply airborne high-resolution thermal infrared imagery for urban heat island studies, using Huntsville, AL, a medium-sized American city, as the study area. The occurrence of urban heat islands represents human-induced urban/rural contrast, which is caused by deforestation and the replacement of the land surface by non-evaporating and non-porous materials such as asphalt and concrete. The result is reduced evapotranspiration and more rapid runoff of rain water. The urban landscape forms a canopy acting as a transitional zone between the atmosphere and the land surface. The composition and structure of this canopy have a significant impact on the thermal behavior of the urban environment. Research on the trends of surface temperature at rapidly growing urban sites in the United States during the last 30 to 50 years suggests that significant urban heat island effects have caused the temperatures at these sites to rise by 1 to 2 C. Urban heat islands have caused changes in urban precipitation and temperature that are at least similar to, if not greater than, those predicted to develop over the next 100 years by global change models. Satellite remote sensing, particularly NOAA AVHRR thermal data, has been used in the study of urban heat islands. Because of the low spatial resolution (1.1 km at nadir) of the AVHRR data, these studies can only examine and map the phenomenon at the macro-level. The present research provides the rare opportunity to utilize 5-meter thermal infrared data acquired from an airplane to characterize more accurately the thermal responses of different land cover types in the urban landscape as input to urban heat island studies.

Urbanization and Land Use Changes in Peri-Urban Area using Spatial Analysis Methods (Case Study: Ciawi Urban Areas, Bogor Regency)

NASA Astrophysics Data System (ADS)

Cahya, D. L.; Martini, E.; Kasikoen, K. M.

2018-02-01

Urbanization is shown by the increasing percentage of the population in urban areas. In Indonesia, the percentage of urban population increased dramatically form 17.42% (1971) to 42.15% (2010). This resulted in increased demand for housing. Limited land in the city area push residents looking for an alternative location of his residence to the peri-urban areas. It is accompanied by a process of land conversion from green area into built-up area. Continuous land conversion in peri-urban area is becoming increasingly widespread. Bogor Regency as part of the Jakarta Metropolitan Area is experiencing rapid development. This regency has been experienced land-use change very rapidly from agricultural areas into urban built up areas. Aim of this research is to analyze the effect of urbanization on land use changes in peri-urban areas using spatial analysis methods. This research used case study of Ciawi Urban Area that experiencing rapid development. Method of this research is using descriptive quantitative approach. Data used in this research is primary data (field survey) and secondary data (maps). To analyze land use change is using Geographic Information System (GIS) as spatial analysis methods. The effect of urbanization on land use changes in Ciawi Urban Area from year 2013 to 2015 is significant. The reduction of farm land is around -4.00% and wetland is around - 2.51%. The increasing area for hotel/villa/resort is around 3.10%. Based on this research, local government (Bogor Regency) should be alert to the land use changes that does not comply with the land use plan and also consistently apply the spatial planning.

A comparison of the influences of urbanization in contrasting environmental settings on stream benthic algal assemblages

USGS Publications Warehouse

Potapova, M.; Coles, J.F.; Giddings, E.M.P.; Zappia, H.

2005-01-01

Patterns of stream benthic algal assemblages along urbanization gradients were investigated in three metropolitan areas-Boston (BOS), Massachusetts; Birmingham (BIR), Alabama; and Salt Lake City (SLC), Utah. An index of urban intensity derived from socioeconomic, infrastructure, and land-use characteristics was used as a measure of urbanization. Of the various attributes of the algal assemblages, species composition changed along gradients of urban intensity in a more consistent manner than biomass or diversity. In urban streams, the relative abundance of pollution-tolerant species was often higher than in less affected streams. Shifts in assemblage composition were associated primarily with increased levels of conductivity, nutrients, and alterations in physical habitat. Water mineralization and nutrients were the most important determinants of assemblage composition in the BOS and SLC study areas; flow regime and grazers were key factors in the BIR study area. Species composition of algal assemblages differed significantly among geographic regions, and no particular algal taxa were found to be universal indicators of urbanization. Patterns in algal biomass and diversity along urban gradients varied among study areas, depending on local environmental conditions and habitat alteration. Biomass and diversity increased with urbanization in the BOS area, apparently because of increased nutrients, light, and flow stability in urban streams, which often are regulated by dams. Biomass and diversity decreased with urbanization in the BIR study area because of intensive fish grazing and less stable flow regime. In the SLC study area, correlations between algal biomass, diversity, and urban intensity were positive but weak. Thus, algal responses to urbanization differed considerably among the three study areas. We concluded that the wide range of responses of benthic algae to urbanization implied that tools for stream bioassessment must be region specific. ?? 2005 by the American Fisheries Society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Xuecao; Zhou, Yuyu; Asrar, Ghassem R.

The influence of urbanization on vegetation phenology is gaining considerable attention due to its implications for human health, cycling of carbon and other nutrients in Earth system. In this study, we examined the relationship between change in vegetation phenology and urban size, an indicator of urbanization, for the conterminous United States. We studied more than 4500 urban clusters of varying size to determine the impact of urbanization on plant phenology, with the aids of remotely sensed observations since 2003–2012. We found that phenology cycle (changes in vegetation greenness) in urban areas starts earlier (start of season, SOS) and ends latermore » (end of season, EOS), resulting in a longer growing season length (GSL), when compared to the respective surrounding urban areas. The average difference of GSL between urban and rural areas over all vegetation types, considered in this study, is about 9 days.Also, the extended GSL in urban area is consistent among different climate zones in the United States, whereas their magnitudes are varying across regions. We found that a tenfold increase in urban size could result in an earlier SOS of about 1.3 days and a later EOS of around 2.4 days. As a result, the GSL could be extended by approximately 3.6 days with a range of 1.6–6.5 days for 25th ~ 75th quantiles, with a median value of about 2.1 days. For different vegetation types, the phenology response to urbanization, as defined by GSL, ranges from 1 to 4 days. In conclusion, the quantitative relationship between phenology and urbanization is of great use for developing improved models of vegetation phenology dynamics under future urbanization, and for developing change indicators to assess the impacts of urbanization on vegetation phenology.« less

Landscape Urbanization and Economic Growth in China: Positive Feedbacks and Sustainability Dilemmas

PubMed Central

2011-01-01

Accelerating urbanization has been viewed as an important instrument for economic development and reducing regional income disparity in some developing countries, including China. Recent studies (Bloom et al. 2008) indicate that demographic urbanization level has no causal effect on economic growth. However, due to the varying and changing definition of urban population, the use of demographic indicators as a sole representing indicator for urbanization might be misleading. Here, we re-examine the causal relationship between urbanization and economic growth in Chinese cities and provinces in recent decades, using built-up areas as a landscape urbanization indicator. Our analysis shows that (1) larger cities, both in terms of population size and built-up area, and richer cities tend to gain more income, have larger built-up area expansion, and attract more population, than poorer cities or smaller cities; and (2) that there is a long-term bidirectional causality between urban built-up area expansion and GDP per capita at both city and provincial level, and a short-term bidirectional causality at provincial level, revealing a positive feedback between landscape urbanization and urban and regional economic growth in China. Our results suggest that urbanization, if measured by a landscape indicator, does have causal effect on economic growth in China, both within the city and with spillover effect to the region, and that urban land expansion is not only the consequences of economic growth in cities, but also drivers of such growth. The results also suggest that under its current economic growth model, it might be difficult for China to control urban expansion without sacrificing economic growth, and China’s policy to stop the loss of agricultural land, for food security, might be challenged by its policy to promote economic growth through urbanization. PMID:22103244

Restorative Qualities of and Preference for Natural and Urban Soundscapes.

PubMed

Krzywicka, Paulina; Byrka, Katarzyna

2017-01-01

Psychological restoration in urban agglomerations has become a growing challenge. Although scientific proof of the significance of nature is irrefutable, an increase in built-up areas has led to a decrease in urban greenery. Thus, a growing need for restorativeness in urban surroundings has emerged. To investigate whether positively evaluated sonic environments, represented by natural and urban sounds, have comparable restorative qualities we conducted two studies. The aim of the first (Study 1) was to explore the restorative qualities of positively assessed natural and urban sounds. Participants ( N = 88) were asked to listen and to rate 22 recordings (each 1 min long) either from natural or urban environments. In the second (Study 2) we investigated whether positively evaluated sonic environments (natural and urban), demand for restoration (feeling relaxed or fatigued) and company (being alone or with a friend) affect the restorative qualities of natural and urban soundscapes. After reading assigned scenarios (feeling relaxed or fatigued; being alone or with a friend), participants ( N = 120) were asked to imagine a walk in presented sonic environments and to complete forms (one for each sonic environment) concerning the restorative qualities of given soundscapes (natural and urban). Top five recordings of natural and urban sonic environments were selected from Study 1 and combined into a 154-s soundtrack, to provide a background for the imagined walks in both settings. Our findings confirmed that natural sounds are perceived more favorably than urban recordings. Even when only the most positively assessed soundscapes were compared, nature was still perceived as being more restorative than urban areas. Company of a friend was found to be more beneficial in the urban surroundings, particularly when there was no need for restoration.

Restorative Qualities of and Preference for Natural and Urban Soundscapes

PubMed Central

Krzywicka, Paulina; Byrka, Katarzyna

2017-01-01

Psychological restoration in urban agglomerations has become a growing challenge. Although scientific proof of the significance of nature is irrefutable, an increase in built-up areas has led to a decrease in urban greenery. Thus, a growing need for restorativeness in urban surroundings has emerged. To investigate whether positively evaluated sonic environments, represented by natural and urban sounds, have comparable restorative qualities we conducted two studies. The aim of the first (Study 1) was to explore the restorative qualities of positively assessed natural and urban sounds. Participants (N = 88) were asked to listen and to rate 22 recordings (each 1 min long) either from natural or urban environments. In the second (Study 2) we investigated whether positively evaluated sonic environments (natural and urban), demand for restoration (feeling relaxed or fatigued) and company (being alone or with a friend) affect the restorative qualities of natural and urban soundscapes. After reading assigned scenarios (feeling relaxed or fatigued; being alone or with a friend), participants (N = 120) were asked to imagine a walk in presented sonic environments and to complete forms (one for each sonic environment) concerning the restorative qualities of given soundscapes (natural and urban). Top five recordings of natural and urban sonic environments were selected from Study 1 and combined into a 154-s soundtrack, to provide a background for the imagined walks in both settings. Our findings confirmed that natural sounds are perceived more favorably than urban recordings. Even when only the most positively assessed soundscapes were compared, nature was still perceived as being more restorative than urban areas. Company of a friend was found to be more beneficial in the urban surroundings, particularly when there was no need for restoration. PMID:29046653

Urban Heat Island towards Urban Climate

NASA Astrophysics Data System (ADS)

Ningrum, Widya

2018-02-01

The urban heat island (UHI) is defined as the temperature difference between the urban and suburban areas and rural areas in the same region. Researchers have discussed several different techniques for evaluating the phenomenon. This paper reviews some of the causes and effects of urban heat islands, mainly on urban climate. Both directly and indirectly, the UHI influences multiple sectors. According to this, it is needed to develop a strategic mitigation between government and scientists to reduce the temperature.

Modeling Global Urbanization Supported by Nighttime Light Remote Sensing

NASA Astrophysics Data System (ADS)

Zhou, Y.

2015-12-01

Urbanization, a major driver of global change, profoundly impacts our physical and social world, for example, altering carbon cycling and climate. Understanding these consequences for better scientific insights and effective decision-making unarguably requires accurate information on urban extent and its spatial distributions. In this study, we developed a cluster-based method to estimate the optimal thresholds and map urban extents from the nighttime light remote sensing data, extended this method to the global domain by developing a computational method (parameterization) to estimate the key parameters in the cluster-based method, and built a consistent 20-year global urban map series to evaluate the time-reactive nature of global urbanization (e.g. 2000 in Fig. 1). Supported by urban maps derived from nightlights remote sensing data and socio-economic drivers, we developed an integrated modeling framework to project future urban expansion by integrating a top-down macro-scale statistical model with a bottom-up urban growth model. With the models calibrated and validated using historical data, we explored urban growth at the grid level (1-km) over the next two decades under a number of socio-economic scenarios. The derived spatiotemporal information of historical and potential future urbanization will be of great value with practical implications for developing adaptation and risk management measures for urban infrastructure, transportation, energy, and water systems when considered together with other factors such as climate variability and change, and high impact weather events.

Change in Environmental Benefits of Urban Land Use and Its Drivers in Chinese Cities, 2000–2010

PubMed Central

Song, Xiaoqing; Chang, Kang-tsung; Yang, Liang; Scheffran, Jürgen

2016-01-01

Driven by rising income and urban population growth, China has experienced rapid urban expansion since the 1980s. Urbanization can have positive effects on the urban environment; however, improvement of urban environment quality, especially its divergence between relatively developed and undeveloped cities in China, is currently a rather rudimentary and subjective issue. This study analyzed urban environmental benefits among China’s prefectural cities based on their structure of urban land use in 2000 and 2010. First, we divided 347 prefectural cities into two groups, 81 coastal and capital cities in the relatively developed group (RD) and 266 other prefectural cities in the undeveloped group (RP). Then, we defined three areas of urban environmental benefits, including green infrastructure, industrial upgrade, and environmental management, and developed an assessment index system. Results showed that all prefectural cities saw improvement in urban environmental quality in 2000–2010. Although the RD cities had higher income and more population growth, they had less improvement than the RP cities during the same period. We also found that demographic and urban land agglomeration among RD cities restrained green infrastructure expansion, making green infrastructure unsuitable as a permanent solution to environmental improvement. It is therefore urgent for China to promote balanced improvement among the three areas of urban environmental benefits and between the RD and RP cities through regional differentiation policies. PMID:27240386

The relationship between urban forests and race: A meta-analysis

PubMed Central

Watkins, Shannon Lea; Gerrish, Ed

2018-01-01

There is ample evidence that urban trees benefit the physical, mental, and social health of urban residents. The environmental justice hypothesis posits that environmental amenities are inequitably low in poor and minority communities, and predicts these communities experience fewer urban environmental benefits. Some previous research has found that urban forest cover is inequitably distributed by race, though other studies have found no relationship or negative inequity. These conflicting results and the single-city nature of the current literature suggest a need for a research synthesis. Using a systematic literature search and meta-analytic techniques, we examined the relationship between urban forest cover and race. First, we estimated the average (unconditional) relationship between urban forest cover and race across studies (studies = 40; effect sizes = 388). We find evidence of significant race-based inequity in urban forest cover. Second, we included characteristics of the original studies and study sites in meta-regressions to illuminate drivers of variation of urban forest cover between studies. Our meta-regressions reveal that the relationship varies across racial groups and by study methodology. Models reveal significant inequity on public land and that environmental and social characteristics of cities help explain variation across studies. As tree planting and other urban forestry programs proliferate, urban forestry professionals are encouraged to consider the equity consequences of urban forestry activities, particularly on public land. PMID:29289843

The relationship between urban forests and race: A meta-analysis.

PubMed

Watkins, Shannon Lea; Gerrish, Ed

2018-03-01

There is ample evidence that urban trees benefit the physical, mental, and social health of urban residents. The environmental justice hypothesis posits that environmental amenities are inequitably low in poor and minority communities, and predicts these communities experience fewer urban environmental benefits. Some previous research has found that urban forest cover is inequitably distributed by race, though other studies have found no relationship or negative inequity. These conflicting results and the single-city nature of the current literature suggest a need for a research synthesis. Using a systematic literature search and meta-analytic techniques, we examined the relationship between urban forest cover and race. First, we estimated the average (unconditional) relationship between urban forest cover and race across studies (studies = 40; effect sizes = 388). We find evidence of significant race-based inequity in urban forest cover. Second, we included characteristics of the original studies and study sites in meta-regressions to illuminate drivers of variation of urban forest cover between studies. Our meta-regressions reveal that the relationship varies across racial groups and by study methodology. Models reveal significant inequity on public land and that environmental and social characteristics of cities help explain variation across studies. As tree planting and other urban forestry programs proliferate, urban forestry professionals are encouraged to consider the equity consequences of urban forestry activities, particularly on public land. Copyright © 2017. Published by Elsevier Ltd.

Urban structure analysis of mega city Mexico City using multisensoral remote sensing data

NASA Astrophysics Data System (ADS)

Taubenböck, H.; Esch, T.; Wurm, M.; Thiel, M.; Ullmann, T.; Roth, A.; Schmidt, M.; Mehl, H.; Dech, S.

2008-10-01

Mega city Mexico City is ranked the third largest urban agglomeration to date around the globe. The large extension as well as dynamic urban transformation and sprawl processes lead to a lack of up-to-date and area-wide data and information to measure, monitor, and understand the urban situation. This paper focuses on the capabilities of multisensoral remotely sensed data to provide a broad range of products derived from one scientific field - remote sensing - to support urban managing and planning. Therefore optical data sets from the Landsat and Quickbird sensors as well as radar data from the Shuttle Radar Topography Mission (SRTM) and the TerraSAR-X sensor are utilised. Using the multi-sensoral data sets the analysis are scale-dependent. On the one hand change detection on city level utilising the derived urban footprints enables to monitor and to assess spatiotemporal urban transformation, areal dimension of urban sprawl, its direction, and the built-up density distribution over time. On the other hand, structural characteristics of an urban landscape - the alignment and types of buildings, streets and open spaces - provide insight in the very detailed physical pattern of urban morphology on higher scale. The results show high accuracies of the derived multi-scale products. The multi-scale analysis allows quantifying urban processes and thus leading to an assessment and interpretation of urban trends.

Change in Environmental Benefits of Urban Land Use and Its Drivers in Chinese Cities, 2000-2010.

PubMed

Song, Xiaoqing; Chang, Kang-Tsung; Yang, Liang; Scheffran, Jürgen

2016-05-26

Driven by rising income and urban population growth, China has experienced rapid urban expansion since the 1980s. Urbanization can have positive effects on the urban environment; however, improvement of urban environment quality, especially its divergence between relatively developed and undeveloped cities in China, is currently a rather rudimentary and subjective issue. This study analyzed urban environmental benefits among China's prefectural cities based on their structure of urban land use in 2000 and 2010. First, we divided 347 prefectural cities into two groups, 81 coastal and capital cities in the relatively developed group (RD) and 266 other prefectural cities in the undeveloped group (RP). Then, we defined three areas of urban environmental benefits, including green infrastructure, industrial upgrade, and environmental management, and developed an assessment index system. Results showed that all prefectural cities saw improvement in urban environmental quality in 2000-2010. Although the RD cities had higher income and more population growth, they had less improvement than the RP cities during the same period. We also found that demographic and urban land agglomeration among RD cities restrained green infrastructure expansion, making green infrastructure unsuitable as a permanent solution to environmental improvement. It is therefore urgent for China to promote balanced improvement among the three areas of urban environmental benefits and between the RD and RP cities through regional differentiation policies.

Urban climate, weather and sustainability

NASA Astrophysics Data System (ADS)

Mills, Gerald

As concentrated areas of human activities, urban areas and urbanization are key drivers of global environmental change and pose a challenge to the achievement of sustainability. One of the key goals of sustainable development is to separate increases in non-renewable resource use (particularly fossil fuels) from economic growth. This is to be accomplished by modifying individual practices, encouraging technological innovation and redesigning systems of production and consumption. Settlements represent a scale at which significant advances on each of these can be made and where there is an existing management structure. However, urban areas currently consume a disproportionate share of the Earth's resources and urbanization has modified local climate and weather significantly, usually to the detriment of urban dwellers. There is now a lengthy history of urban climate study that links existing settlement form to climatic consequences yet, there is little evidence that climate information is incorporated into urban designs or that the climatic impact of different plans is considered. Consequently, opportunities for planning sustainable urban forms that are suitable to local climates and promote energy conservation and healthy atmospheres are not taken and much effort is later expended in `fixing' problems that emerge. This paper will outline the links between urban climate and sustainability, identify gaps in our urban climate knowledge and discuss the opportunities and barriers to the application of this knowledge to urban design and planning.

A GIS approach to urban heat island research: The case of Huntsville, Alabama

NASA Technical Reports Server (NTRS)

Lo, Chor Pong

1994-01-01

The urban heat island represents a case of inadvertent human modification of climate in an urban environment. Urbanization changes the nature of the surface and atmospheric properties of a region. As a result, radiation balance in the urban areas is altered and sensible heat is added to the point that urban areas are warmer than surrounding rural areas. At the boundary between the rural and urban area, a sharp rise in temperature occurs, culminating to a peak temperature at the central business district of the city, hence the name 'urban heat island'. The extent and intensity of the urban heat island are a function of population size, land use, and topography. Because the urban heat island exhibits spatial variations of temperatures, the use of Geographic Information System (GIS) is appropriate. The research on the urban heat island focuses on the acquisition of 15 bands of visible and thermal infrared data (ranging from 0.45 to 12.2 microns) from an aerial platform using NASA's ATLAS (Airborne Thermal/Visible Land Application Sensor) over Huntsville, Alabama. The research reported in this paper is an analysis of the impact of population, land use, and topography on the shape of the urban heat island that could be developed in Huntsville using the GIS approach. The outcome of this analysis can then be verified using the acquired remotely sensed data.

Is sprawl associated with a widening urban-suburban mortality gap?

PubMed

Fan, Yingling; Song, Yan

2009-09-01

This paper examines whether sprawl, featured by low development density, segregated land uses, lack of significant centers, and poor street connectivity, contributes to a widening mortality gap between urban and suburban residents. We employ two mortality datasets, including a national cross-sectional dataset examining the impact of metropolitan-level sprawl on urban-suburban mortality gaps and a longitudinal dataset from Portland examining changes in urban-suburban mortality gaps over time. The national and Portland studies provide the only evidence to date that (1) across metropolitan areas, the size of urban-suburban mortality gaps varies by the extent of sprawl: in sprawling metropolitan areas, urban residents have significant excess mortality risks than suburban residents, while in compact metropolitan areas, urbanicity-related excess mortality becomes insignificant; (2) the Portland metropolitan area not only experienced net decreases in mortality rates but also a narrowing urban-suburban mortality gap since its adoption of smart growth regime in the past decade; and (3) the existence of excess mortality among urban residents in US sprawling metropolitan areas, as well as the net mortality decreases and narrowing urban-suburban mortality gap in the Portland metropolitan area, is not attributable to sociodemographic variations. These findings suggest that health threats imposed by sprawl affect urban residents disproportionately compared to suburban residents and that efforts curbing sprawl may mitigate urban-suburban health disparities.

Global perspectives on the urban stream syndrome

USGS Publications Warehouse

Roy, Allison; Booth, Derek B.; Capps, Krista A.; Smith, Benjamin

2016-01-01

Urban streams commonly express degraded physical, chemical, and biological conditions that have been collectively termed the “urban stream syndrome”. The description of the syndrome highlights the broad similarities among these streams relative to their less-impaired counterparts. Awareness of these commonalities has fostered rapid improvements in the management of urban stormwater for the protection of downstream watercourses, but the focus on the similarities among urban streams has obscured meaningful differences among them. Key drivers of stream responses to urbanization can vary greatly among climatological and physiographic regions of the globe, and the differences can be manifested in individual stream channels even through the homogenizing veneer of urban development. We provide examples of differences in natural hydrologic and geologic settings (within similar regions) that can result in different mechanisms of stream ecosystem response to urbanization and, as such, should lead to different management approaches. The idea that all urban streams can be cured using the same treatment is simplistic, but overemphasizing the tremendous differences among natural (or human-altered) systems also can paralyze management. Thoughtful integration of work that recognizes the commonalities of the urban stream syndrome across the globe has benefitted urban stream management. Now we call for a more nuanced understanding of the regional, subregional, and local attributes of any given urban stream and its watershed to advance the physical, chemical, and ecological recovery of these systems.

Squatting and urban renewal: the interaction of squatter movements and strategies of urban restructuring in Berlin.

PubMed

Holm, Andrej; Kuhn, Armin

2011-01-01

Squatting as a housing strategy and as a tool of urban social movements accompanies the development of capitalist cities worldwide. We argue that the dynamics of squatter movements are directly connected to strategies of urban renewal in that movement conjunctures occur when urban regimes are in crisis. An analysis of the history of Berlin squatter movements, their political context and their effects on urban policies since the 1970s, clearly shows how massive mobilizations at the beginning of the 1980s and in the early 1990s developed in a context of transition in regimes of urban renewal. The crisis of Fordist city planning at the end of the 1970s provoked a movement of "rehab squatting" ('Instandbesetzung'), which contributed to the institutionalization of "cautious urban renewal" ('behutsame Stadterneuerung') in an important way. The second rupture in Berlin's urban renewal became apparent in 1989 and 1990, when the necessity of restoring whole inner-city districts constituted a new, budget-straining challenge for urban policymaking. Whilst in the 1980s the squatter movement became a central condition for and a political factor of the transition to "cautious urban renewal," in the 1990s large-scale squatting — mainly in the eastern parts of the city — is better understood as an alien element in times of neoliberal urban restructuring.

Understanding, management and modelling of urban hydrology and its consequences for receiving waters: A state of the art

NASA Astrophysics Data System (ADS)

Fletcher, T. D.; Andrieu, H.; Hamel, P.

2013-01-01

Urban hydrology has evolved to improve the way urban runoff is managed for flood protection, public health and environmental protection. There have been significant recent advances in the measurement and prediction of urban rainfall, with technologies such as radar and microwave networks showing promise. The ability to predict urban hydrology has also evolved, to deliver models suited to the small temporal and spatial scales typical of urban and peri-urban applications. Urban stormwater management increasingly consider the needs of receiving environments as well as those of humans. There is a clear trend towards approaches that attempt to restore pre-development flow-regimes and water quality, with an increasing recognition that restoring a more natural water balance benefits not only the environment, but enhances the liveability of the urban landscape. Once regarded only as a nuisance, stormwater is now increasingly regarded as a resource. Despite the advances, many important challenges in urban hydrology remain. Further research into the spatio-temporal dynamics of urban rainfall is required to improve short-term rainfall prediction. The performance of stormwater technologies in restoring the water balance and in removing emerging priority pollutants remain poorly quantified. All of these challenges are overlaid by the uncertainty of climate change, which imposes a requirement to ensure that stormwater management systems are adaptable and resilient to changes. Urban hydrology will play a critical role in addressing these challenges.

Urban spring phenology in the middle temperate zone of China: dynamics and influence factors.

PubMed

Liang, Shouzhen; Shi, Ping; Li, Hongzhong

2016-04-01

Urbanization and its resultant urban heat island provide a means for evaluating the impact of climate warming on vegetation phenology. To predict the possible response of vegetation phenology to rise of temperature, it is necessary to investigate factors influencing vegetation phenology in different climate zones. The start of growing season (SOS) in seven cities located in the middle temperate humid, semi-humid, semi-arid, and arid climate zones in China was extracted based on satellite-derived normalized difference vegetation index (NDVI) data. The dynamics of urban SOS from 2000 to 2009 and the correlations between urban SOS and land surface temperatures (LST), precipitation, and sunshine duration, respectively, were analyzed. The results showed that there were no obvious change trends for urban SOS, and the heat island induced by urbanization can make SOS earlier in urban areas than that in adjacent rural areas. And the impact of altitude on SOS was also not negligible in regions with obvious altitude difference between urban and adjacent rural areas. Precipitation and temperature were two main natural factors influencing urban SOS in the middle temperate zone, but their impacts varied with climate zones. Only in Harbin city with lower sunshine duration in spring, sunshine duration had more significant impact than temperature and precipitation. Interference of human activities on urban vegetation was non-negligible, which can lower the dependence of urban SOS on natural climatic factors.

The Urban Food Hubs Solution: Building Capacity in Urban Communities

ERIC Educational Resources Information Center

O'Hara, Sabine

2017-01-01

Access to affordable fresh food is an ongoing challenge for underserved urban neighborhoods across the United States. Several are designated food deserts with no access to a full-service grocery store within a one-mile radius. The Urban Food Hubs of the College of Agriculture, Urban Sustainability, and Environmental Sciences (CAUSES) of the…

Assessing the Educational Needs of Urban Gardeners and Farmers on the Subject of Soil Contamination

ERIC Educational Resources Information Center

Harms, Ashley Marie Raes; Presley, DeAnn Ricks; Hettiarachchi, Ganga M.; Thien, Stephen J.

2013-01-01

Participation in urban agriculture is growing throughout the United States; however, potential soil contaminants in urban environments present challenges. Individuals in direct contact with urban soil should be aware of urban soil quality and soil contamination issues to minimize environmental and human health risks. The study reported here…

Stormwater Management Impacts on Urban Stream Water Quality and Quantity During and After Development in Clarksburg, MD

EPA Science Inventory

Urbanization and urban land use leads to degradation of local stream habitat generally termed as ‘urban stream syndrome.’ Best Management Practices (BMPs) are often used in an attempt to mitigate water quality and water quantity degradation in urban streams. Traditional developme...

Urban and natural components of Korean magpie (Pica pica sericea) territories and their effects on prey density

USDA-ARS?s Scientific Manuscript database

Urban landscapes have a negative impact on bird species diversity, yet particular species thrive in urban communities. Like many other corvids, the Korean black-billed magpie is a successful colonizer of urban environments. On the semi-urban campus of Seoul National University in Korea, we investiga...

Focus for Area Development Analysis: Urban Orientation of Counties.

ERIC Educational Resources Information Center

Bluestone, Herman

The orientation of counties to metropolitan systems and urban centers is identified by population density and percentage of urban population. This analytical framework differentiates 6 kinds of counties, ranging from most urban-oriented (group 1) to least urban-oriented (group 6). With this framework, it can be seen that the economic well-being of…

78 FR 40746 - Urban Indian Education and Research Organization Cooperative Agreement Program; Office of Urban...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-08

... Training and Technical Assistance for UIOs, Education, Public Relations, and Marketing of UIOs This section... assistance for urban Indian organizations, and (4) education, public relations and marketing of urban Indian... and Marketing of Urban Indian Organizations A. Applicants should summarize the need to market the...

FACILITATING ADVANCED URBAN METEOROLOGY AND AIR QUALITY MODELING CAPABILITIES WITH HIGH RESOLUTION URBAN DATABASE AND ACCESS PORTAL TOOLS

EPA Science Inventory

Information of urban morphological features at high resolution is needed to properly model and characterize the meteorological and air quality fields in urban areas. We describe a new project called National Urban Database with Access Portal Tool, (NUDAPT) that addresses this nee...

Forests [Chapter 7

Treesearch

Linda A. Joyce; Steven W. Running; David D. Breshears; Virginia H. Dale; Robert W. Malmsheimer; R. Neil Sampson; Brent Sohngen; Christopher W. Woodall

2014-01-01

Forests occur within urban areas, at the interface between urban and rural areas (wildland-urban interface), and in rural areas. Urban forests contribute to clean air, cooling buildings, aesthetics, and recreation in parks. Development in the wildland-urban interface is increasing because of the appeal of owning homes near or in the woods. In rural areas, market...

Urban Geography: Topics in Geography, Number 1.

ERIC Educational Resources Information Center

National Council for Geographic Education.

The scope, objectives, and some of the findings of urban geography are discussed in this paper. Curriculum development in urban geography at the high-school level is also briefly described. The first of six articles, "Aspects and Trends of Urban Geography," explains the urban geographer's interest in internal city structure, interaction of static…

Using urban forest assessment tools to model bird habitat potential

Treesearch

Susannah B. Lerman; Keith H. Nislow; David J. Nowak; Stephen DeStefano; David I. King; D. Todd Jones-Farrand

2014-01-01

The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat...

[The use of census data to estimate levels of urbanization].

PubMed

Darwin, M; Tukiran

1991-01-01

Problems concerning changes in the definition of urbanization for demographic analysis are examined. "This article attempts to examine the problem by clarifying the definition of the concept and indicators of urban and urbanization and by making a longitudinal analysis of urbanization using the Indonesian 1920-1990 Census data." (SUMMARY IN ENG) excerpt

Institutionalizing urban forestry as a "biotechnology" to improve environmental quality

Treesearch

David J. Nowak

2006-01-01

Urban forests can provide multiple environmental benefits. As urban areas expand, the role of urban vegetation in improving environmental quality will increase in importance. Quantification of these benefits has revealed that urban forests can significantly improve air quality. As a result, national air quality regulations are now willing to potentially credit tree...

Evolution of life in urban environments.

PubMed

Johnson, Marc T J; Munshi-South, Jason

2017-11-03

Our planet is an increasingly urbanized landscape, with over half of the human population residing in cities. Despite advances in urban ecology, we do not adequately understand how urbanization affects the evolution of organisms, nor how this evolution may affect ecosystems and human health. Here, we review evidence for the effects of urbanization on the evolution of microbes, plants, and animals that inhabit cities. Urbanization affects adaptive and nonadaptive evolutionary processes that shape the genetic diversity within and between populations. Rapid adaptation has facilitated the success of some native species in urban areas, but it has also allowed human pests and disease to spread more rapidly. The nascent field of urban evolution brings together efforts to understand evolution in response to environmental change while developing new hypotheses concerning adaptation to urban infrastructure and human socioeconomic activity. The next generation of research on urban evolution will provide critical insight into the importance of evolution for sustainable interactions between humans and our city environments. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Analysis of long-term trends (1950–2009) in precipitation, runoff and runoff coefficient in major urban watersheds in the United States

USGS Publications Warehouse

Velpuri, N.M.; Senay, G.B.

2013-01-01

This study investigates the long-term trends in precipitation, runoff and runoff coefficient in major urban watersheds in the United States. The seasonal Mann–Kendall trend test was performed on monthly precipitation, runoff and runoff coefficient data from 1950 to 2009 obtained from 62 urban watersheds covering 21 major urban centers in the United States. The results indicate that only five out of 21 urban centers in the United States showed an uptrend in precipitation. Twelve urban centers showed an uptrend in runoff coefficient. However, six urban centers did not show any trend in runoff coefficient, and three urban centers showed a significant downtrend. The highest rate of change in precipitation, runoff and runoff coefficient was observed in the Houston urban watershed. Based on the results obtained, we also attributed plausible causes for the trends. Our analysis indicated that while a human only influence is observed in most of the urban watersheds, a combined climate and human influence is observed in the central United States.

Detection of urban expansion in an urban-rural landscape with multitemporal QuickBird images

PubMed Central

Lu, Dengsheng; Hetrick, Scott; Moran, Emilio; Li, Guiying

2011-01-01

Accurately detecting urban expansion with remote sensing techniques is a challenge due to the complexity of urban landscapes. This paper explored methods for detecting urban expansion with multitemporal QuickBird images in Lucas do Rio Verde, Mato Grosso, Brazil. Different techniques, including image differencing, principal component analysis (PCA), and comparison of classified impervious surface images with the matched filtering method, were used to examine urbanization detection. An impervious surface image classified with the hybrid method was used to modify the urbanization detection results. As a comparison, the original multispectral image and segmentation-based mean-spectral images were used during the detection of urbanization. This research indicates that the comparison of classified impervious surface images with matched filtering method provides the best change detection performance, followed by the image differencing method based on segmentation-based mean spectral images. The PCA is not a good method for urban change detection in this study. Shadows and high spectral variation within the impervious surfaces represent major challenges to the detection of urban expansion when high spatial resolution images are used. PMID:21799706

Impacts of urbanization on regional nonpoint source pollution: case study for Beijing, China.

PubMed

Zhi, Xiaosha; Chen, Lei; Shen, Zhenyao

2018-04-01

Due to limits on available data, the effects of urban sprawl on regional nonpoint source pollution (NPS) have not been investigated over long time periods. In this paper, the characteristics of urban sprawl from 1999 to 2014 in Beijing were explored by analyzing historical land-use data. The Event Mean Concentration data have been collected from all available references, which were used to estimate the variation in urban NPSs. Moreover, the impacts of variation in urban sprawl on regional NPSs were qualified. The results indicated that the urbanization process showed different influences on pollutants, while COD and TN were identified as key NPS pollutants. Residential areas contributed more NPS pollutants than did roads, which played a tremendous role in the control of urban NPS. The results also suggested in part that the impact of urban sprawl on the variation of COD decreased while TN increased in Beijing during the study period. These results would provide insight into the impacts of urban sprawl on NPS variation over a long period, as well as the reference for reasonable urban planning directives.

RNICO: a new simple geometric index for assessing the impact of urban development pattern on peak flows in urban catchments

NASA Astrophysics Data System (ADS)

Kasaee Roodsari, B.; Chandler, D. G.

2016-12-01

Urban sprawl is widespread across the world and the associated hydrologic impacts are increasing in peri-urban catchments due to increased area of impervious. There is a strong agreement on the positive correlation between the fractional impervious area and peak flows in urban catchments. Nevertheless, the effect of land development pattern on peak flows is not well investigated. In this study, a new simple geometric index, Relative Nearness of Imperviousness to the Catchment Outlet (RNICO), is defined to correlate imperviousness distribution of peri-urban catchments to runoff peak flows. Results of applying RNICO to 20 sub-catchments in New York State showed a strong positive correlation (R2>0.97) between RNICO and runoff peak flows for small peri-urban catchments (A< 42 km2) indicating higher flood risk of downstream urbanization. For large catchments (A> 42 km2), no correlation was indicated between RNICO and peak flows. We highlight the necessity of a greater discharge monitoring network at small peri-urban catchments to support local urban flood forecast.

Shyer and larger bird species show more reduced fear of humans when living in urban environments.

PubMed

delBarco-Trillo, Javier

2018-04-01

As the natural habitats of many species are degraded or disappear, there is scope for these species to be established in urban habitats. To ease the establishment and maintenance of urban populations of more species we need to better understand what degree of phenotypical change to expect as different species transition into urban environments. During the first stages of urban colonization, behavioural changes such as an increase in boldness are particularly important. A consistent response in urban populations is to decrease the distance at which individuals flee from an approaching human (flight initiation distance, or FID). Performing a phylogenetic generalized least-squares (PGLS) analysis on 130 avian species, I found that the largest changes in FID between rural and urban populations occur in species that are larger-bodied and naturally shy (higher rural FID), two phenotypic traits that are not normally associated with urban colonizers. More unlikely species may thus be able to colonize urban environments, especially if we design cities in ways that promote such urban colonizations. © 2018 The Author(s).

Innovativeness and the effects of urbanization on risk-taking behaviors in wild Barbados birds.

PubMed

Ducatez, Simon; Audet, Jean-Nicolas; Rodriguez, Jordi Ros; Kayello, Lima; Lefebvre, Louis

2017-01-01

The effects of urbanization on avian cognition remain poorly understood. Risk-taking behaviors like boldness, neophobia and flight distance are thought to affect opportunism and innovativeness, and should also vary with urbanization. Here, we investigate variation in risk-taking behaviors in the field in an avian assemblage of nine species that forage together in Barbados and for which innovation rate is known from previous work. We predicted that birds from highly urbanized areas would show more risk-taking behavior than conspecifics from less urbanized parts of the island and that the differences would be strongest in the most innovative of the species. Overall, we found that urban birds are bolder, less neophobic and have shorter flight distances than their less urbanized conspecifics. Additionally, we detected between-species differences in the effect of urbanization on flight distance, more innovative species showing smaller differences in flight distance between areas. Our results suggest that, within successful urban colonizers, species differences in innovativeness may affect the way species change their risk-taking behaviors in response to the urban environment.

Urban change analysis and future growth of Istanbul.

PubMed

Akın, Anıl; Sunar, Filiz; Berberoğlu, Süha

2015-08-01

This study is aimed at analyzing urban change within Istanbul and assessing the city's future growth potential using appropriate approach modeling for the year 2040. Urban growth is a major driving force of land-use change, and spatial and temporal components of urbanization can be identified through accurate spatial modeling. In this context, widely used urban modeling approaches, such as the Markov chain and logistic regression based on cellular automata (CA), were used to simulate urban growth within Istanbul. The distance from each pixel to the urban and road classes, elevation, and slope, together with municipality and land use maps (as an excluded layer), were identified as factors. Calibration data were obtained from remotely sensed data recorded in 1972, 1986, and 2013. Validation was performed by overlaying the simulated and actual 2013 urban maps, and a kappa index of agreement was derived. The results indicate that urban expansion will influence mainly forest areas during the time period of 2013-2040. The urban expansion was predicted as 429 and 327 km(2) with the Markov chain and logistic regression models, respectively.

[Urbanization mechanisms in bird species: population systems transformations or adaptations at the individual level?].

PubMed

Fridman, V S; Eremkin, G S; Zakharova-Kubareva, N Iu

2008-01-01

The present research deals with urbanization of wild bird and mammal species. Forms and mechanisms of population steadiness in the urban landscape have been examined. The urbanization process turned out to be a directed change of the population system forming de novo in the urbolandscape leading to a sustainable organization peculiar for the particular environment. The population organization of different types in urbolandscape is found to provide its stability under conditions of directed and fast changes accompanied with instability and heterogenous structure of habitats. It is shown that the same type of population organization meets the corresponding demands among different species settling in the urban environment. Its features are "openness" and "flowage" of the groups, far order of settlement levels and other units of population system, constant movements of the individuals between the groups as a respond to the signals of urboenvironment significant changes. The "urban" variant of the population system organization turns out to be opposite to that of the same species in the non-urban habitats. After formation of the urban types by the species and successful developing of the town, the urban population becomes separated from the maternal local population and begins to exist independently in the urban landscape. The variety of adaptation aberrations in ecology, behavior, and mode of life of urban birds is the population system stability function in the urban landscape and is not a results of individual selection. It is shown that the urbanization process of the species goes firstly on the population level being the system structure transformation developed by the species towards the most stable state in the town (city) territory. Only after the appearance of stable urban population, the urban individuals show the rapid growth of different changes in ecology, behavior, mode of life that was traditionally described by naturalists as species adaptation to the city conditions. The key features of urban population stability/instability are described. Their application to closely related species allows us to distinguish potential urbanists from instable and vulnerable species that could be soon pushed out of the city. The application of corresponding criteria to the urban populations of such species constituting one guild allows us to predict if their developing in the given town would be successful or unsuccessful. The latter is very important since close species are, as a rule, ecologically indistinguishable in the urbanized landscapes. So one can not predict successful/unsuccessful urbanization taking into account the differences in the range of habitats, breeding success, and other external features.

Urban-rural differentials in child malnutrition: trends and socioeconomic correlates in sub-Saharan Africa.

PubMed

Fotso, Jean-Christophe

2007-03-01

This paper examines levels and trends of urban-rural differentials in child malnutrition, and investigates whether residual differences exist between urban and rural areas, given comparable measures of socioeconomic status (SES) of households and communities. Using data from Demographic and Health Surveys of 15 sub-Saharan African countries, and multilevel modelling, it shows that urban-rural differentials are considerable in all countries, that they have narrowed in most countries due primarily to an increase in urban malnutrition, and have widened in few countries as a result of sharp decline in urban malnutrition. These urban-rural gaps are abolished in almost all countries when SES is controlled. These results suggest that policies and programs contributing to the attainment of the MDGs should pay particular attention to the urban poor.

A new assessment method for urbanization environmental impact: urban environment entropy model and its application.

PubMed

Ouyang, Tingping; Fu, Shuqing; Zhu, Zhaoyu; Kuang, Yaoqiu; Huang, Ningsheng; Wu, Zhifeng

2008-11-01

The thermodynamic law is one of the most widely used scientific principles. The comparability between the environmental impact of urbanization and the thermodynamic entropy was systematically analyzed. Consequently, the concept "Urban Environment Entropy" was brought forward and the "Urban Environment Entropy" model was established for urbanization environmental impact assessment in this study. The model was then utilized in a case study for the assessment of river water quality in the Pearl River Delta Economic Zone. The results indicated that the assessing results of the model are consistent to that of the equalized synthetic pollution index method. Therefore, it can be concluded that the Urban Environment Entropy model has high reliability and can be applied widely in urbanization environmental assessment research using many different environmental parameters.

An inter-model comparison of urban canopy effects on climate

NASA Astrophysics Data System (ADS)

Halenka, Tomas; Karlicky, Jan; Huszar, Peter; Belda, Michal; Bardachova, Tatsiana

2017-04-01

The role of cities is increasing and will continue to increase in future, as the population within the urban areas is growing faster, with the estimate for Europe of about 84% living in urban areas in about mid of 21st century. To assess the impact of cities and, in general, urban surfaces on climate, using of modeling approach is well appropriate. Moreover, with higher resolution, urban areas becomes to be better resolved in the regional models and their relatively significant impacts should not be neglected. Model descriptions of urban canopy related meteorological effects can, however, differ largely given the odds in the driving models, the underlying surface models and the urban canopy parameterizations, representing a certain uncertainty. In this study we try to contribute to the estimation of this uncertainty by performing numerous experiments to assess the urban canopy meteorological forcing over central Europe on climate for the decade 2001-2010, using two driving models (RegCM4 and WRF) in 10 km resolution driven by ERA-Interim reanalyses, three surface schemes (BATS and CLM4.5 for RegCM4 and Noah for WRF) and five urban canopy parameterizations available: one bulk urban scheme, three single layer and a multilayer urban scheme. Actually, in RegCM4 we used our implementation of the Single Layer Urban Canopy Model (SLUCM) in BATS scheme and CLM4.5 option with urban parameterization based on SLUCM concept as well, in WRF we used all the three options, i.e. bulk, SLUCM and more complex and sophisticated Building Environment Parameterization (BEP) connected with Building Energy Model (BEM). As a reference simulations, runs with no urban areas and with no urban parameterizations were performed. Effects of cities on urban and rural areas were evaluated. Effect of reducing diurnal temperature range in cities (around 2 °C in summer) is noticeable in all simulation, independent to urban parameterization type and model. Also well-known warmer summer city nights appear in all simulations. Further, winter boundary layer increase by 100-200 m, together with wind reduction, is visible in all simulations. The spatial distribution of the night-time temperature response of models to urban canopy forcing is rather similar in each set-up, showing temperature increases up to 3°C in summer. In general, much lower increase are modeled for day-time conditions, which can be even slightly negative due to dominance of shadowing in urban canyons, especially in the morning hours. The winter temperature response, driven mainly by anthropogenic heat (AH) is strong in urban schemes where the building-street energy exchange is more resolved and is smaller, where AH is simply prescribed as additive flux to the sensible heat. Somewhat larger differences between the models are encountered for the response of wind and the height of planetary boundary layer (ZPBL), with dominant increases from a few 10 m up to 250 m depending on the model. The comparison of observation of diurnal temperature amplitude from ECAD data with model results and hourly data from Prague with model hourly values show improvement when urban effects are considered. Larger spread encountered for wind and turbulence (as ZPBL) should be considered when choices of urban canopy schemes are made, especially in connection with modeling transport of pollutants within/from cities. Another conclusion is that choosing more complex urban schemes does not necessary improves model performance and using simpler and computationally less demanding (e.g. single layer) urban schemes, is often sufficient.

Cooling Effect of Evapotranspiration (ET) and ET Measurement by Thermal Remote Sensing in Urban

NASA Astrophysics Data System (ADS)

Qiu, G. Y.; Yang, B.; Li, X.; Guo, Q.; Tan, S.

2015-12-01

Affected by global warming and rapid urbanization, urban thermal environment and livability are getting worse over the world. Global terrestrial evapotranspiration (ET) can annually consume 1.483 × 1023 joules of solar energy, which is about 300 times of the annual human energy use on the earth (4.935×1020 joules). This huge amount of energy use by ET indicates that there is great potential to cool the urban by regulating ET. However, accurately measurement of urban ET is quiet difficult because of the great spatial heterogeneity in urban. This study focuses on to quantify the cooling effects ET by mobile traverse method and improve a methodology to measure the urban ET by thermal remote sensing. The verifying experiment was carried out in Shenzhen, a sub-tropical mega city in China. Results showed that ET of vegetation could obviously reduce the urban temperature in hot season. Daily transpiration rate of a small-sized Ficus tree (Ficus microcarpa, 5 m in height and 20 cm of trunk diameter, measured by sap-flow method) was 36-55 kg and its cooling effect was equivalent to a 1.6-2.4 kWh air conditioner working for 24 hours. A 10% increase in the vegetated area could decrease urban temperature by 0.60°C at hot night. Moreover, it was found that a region with a vegetated area ratio over 55% had obvious effect on temperature decreasing. In addition, a methodology by using "thermal remote sensing + three-temperature model" was improved to measure the urban ET. Results showed that the urban ET could be reasonably measured by the proposed method. The daily ET of an urban lawn was 0.01-2.86 mm and monthly ET was 21-60 mm. This result agreed well with the verification study (Bowen ratio method, r=0.953). These results are very useful for urban planning, urban lower impact development, and improving of urban thermal environment.

Is the Urban Child Health Advantage Declining in Malawi?: Evidence from Demographic and Health Surveys and Multiple Indicator Cluster Surveys.

PubMed

Lungu, Edgar Arnold; Biesma, Regien; Chirwa, Maureen; Darker, Catherine

2018-06-01

In many developing countries including Malawi, health indicators are on average better in urban than in rural areas. This phenomenon has largely prompted Governments to prioritize rural areas in programs to improve access to health services. However, considerable evidence has emerged that some population groups in urban areas may be facing worse health than rural areas and that the urban advantage may be waning in some contexts. We used a descriptive study undertaking a comparative analysis of 13 child health indicators between urban and rural areas using seven data points provided by nationally representative population based surveys-the Malawi Demographic and Health Surveys and Multiple Indicator Cluster Surveys. Rate differences between urban and rural values for selected child health indicators were calculated to denote whether urban-rural differentials showed a trend of declining urban advantage in Malawi. The results show that all forms of child mortality have significantly declined between 1992 and 2015/2016 reflecting successes in child health interventions. Rural-urban comparisons, using rate differences, largely indicate a picture of the narrowing gap between urban and rural areas albeit the extent and pattern vary among child health indicators. Of the 13 child health indicators, eight (neonatal mortality, infant mortality, under-five mortality rates, stunting rate, proportion of children treated for diarrhea and fever, proportion of children sleeping under insecticide-treated nets, and children fully immunized at 12 months) show clear patterns of a declining urban advantage particularly up to 2014. However, U-5MR shows reversal to a significant urban advantage in 2015/2016, and slight increases in urban advantage are noted for infant mortality rate, underweight, full childhood immunization, and stunting rate in 2015/2016. Our findings suggest the need to rethink the policy viewpoint of a disadvantaged rural and much better-off urban in child health programming. Efforts should be dedicated towards addressing determinants of child health in both urban and rural areas.

Determinants of urban resource use and resilience: a comprehensive framework

NASA Astrophysics Data System (ADS)

Romero-Lankao, P.; Bourgeron, P.; Gochis, D. J.; Rothman, D. S.; Wilhelmi, O.

2015-12-01

During the past decades urbanization has proceeded at unprecedented - yet varied - rates across urban areas globally. The social and environmental transformations implied by urban development have put many regions at risk of transforming the very characteristics that make them attractive and healthy. Meanwhile, climate change is adding new sources of risk and an array of uncertainties to the mix. These changes create risks that vary according to the characteristics of the demographic, economic, ecological, built-environment (technological) and governance dimensions of urbanization and urban areas as socioecological systems. However, few studies have explored the variation in these dimensions across urban areas. I will present a comprehensive analytical framework that explores, in urban areas, patterns of interplay, synergy and tradeoff between socio-demographic, economic, technological, ecological, and governance (SETEG) factors as they shape two issues, traditionally analyzed by separate disciplinary domains: resource use and resilience to climate hazards. Three questions guide this effort: 1) What indicators can be used to socio-demographic, economic, technological, ecological, and governance (SETEG) determinants of urban populations' resource use and resilience to climate hazards? 2) What indicators are important? 3) What combinations (i.e., tradeoffs, synergies) of causal factors better explain urban populations' resource use and resilience to hazards? The interplay between these factors as they shape a population's resource use and resilience is not exempted from synergies and tradeoffs that require careful analysis. Consider population density, a key indicator of urban form. Scholars have found that while more compact cities are more energy efficient and emit less GHG, heat stress is much worse in more compact cities. This begs the question of which combination of urban form factors need to be considered by urban planners when designing effective urban/environmental interventions. The framework, that builds on empirical work globally and in the cities of Buenos Aires, Mexico, Santiago and Mumbai, is intended to inform the design of more effective urban mitigation and adaptation policies.

Increased body size along urbanization gradients at both community and intraspecific level in macro-moths.

PubMed

Merckx, Thomas; Kaiser, Aurélien; Van Dyck, Hans

2018-05-23

Urbanization involves a cocktail of human-induced rapid environmental changes and is forecasted to gain further importance. Urban-heat-island effects result in increased metabolic costs expected to drive shifts towards smaller body sizes. However, urban environments are also characterized by strong habitat fragmentation, often selecting for dispersal phenotypes. Here, we investigate to what extent, and at which spatial scale(s), urbanization drives body size shifts in macro-moths-an insect group characterized by positive size-dispersal links-at both the community and intraspecific level. Using light and bait trapping as part of a replicated, spatially nested sampling design, we show that despite the observed urban warming of their woodland habitat, macro-moth communities display considerable increases in community-weighted mean body size because of stronger filtering against small species along urbanization gradients. Urbanization drives intraspecific shifts towards increased body size too, at least for a third of species analysed. These results indicate that urbanization drives shifts towards larger, and hence, more mobile species and individuals in order to mitigate low connectivity of ecological resources in urban settings. Macro-moths are a key group within terrestrial ecosystems, and since body size is central to species interactions, such urbanization-driven phenotypic change may impact urban ecosystem functioning, especially in terms of nocturnal pollination and food web dynamics. Although we show that urbanization's size-biased filtering happens simultaneously and coherently at both the inter- and intraspecific level, we demonstrate that the impact at the community level is most pronounced at the 800 m radius scale, whereas species-specific size increases happen at local and landscape scales (50-3,200 m radius), depending on the species. Hence, measures-such as creating and improving urban green infrastructure-to mitigate the effects of urbanization on body size will have to be implemented at multiple spatial scales in order to be most effective. © 2018 John Wiley & Sons Ltd.

Response of vegetation phenology to urbanization in the conterminous United States.

PubMed

Li, Xuecao; Zhou, Yuyu; Asrar, Ghassem R; Mao, Jiafu; Li, Xiaoma; Li, Wenyu

2017-07-01

The influence of urbanization on vegetation phenology is gaining considerable attention due to its implications for human health, cycling of carbon and other nutrients in Earth system. In this study, we examined the relationship between change in vegetation phenology and urban size, an indicator of urbanization, for the conterminous United States. We studied more than 4500 urban clusters of varying size to determine the impact of urbanization on plant phenology, with the aids of remotely sensed observations since 2003-2012. We found that phenology cycle (changes in vegetation greenness) in urban areas starts earlier (start of season, SOS) and ends later (end of season, EOS), resulting in a longer growing season length (GSL), when compared to the respective surrounding urban areas. The average difference of GSL between urban and rural areas over all vegetation types, considered in this study, is about 9 days. Also, the extended GSL in urban area is consistent among different climate zones in the United States, whereas their magnitudes are varying across regions. We found that a tenfold increase in urban size could result in an earlier SOS of about 1.3 days and a later EOS of around 2.4 days. As a result, the GSL could be extended by approximately 3.6 days with a range of 1.6-6.5 days for 25th ~ 75th quantiles, with a median value of about 2.1 days. For different vegetation types, the phenology response to urbanization, as defined by GSL, ranges from 1 to 4 days. The quantitative relationship between phenology and urbanization is of great use for developing improved models of vegetation phenology dynamics under future urbanization, and for developing change indicators to assess the impacts of urbanization on vegetation phenology. © 2016 John Wiley & Sons Ltd.

Social urbanization in the Cauca Valley, Colombia.

PubMed

Whiteford, M B

1979-01-01

"This paper treats aspects of the urbanization of the countryside occurring in southern Colombia. It focuses on those urban-emanating forces that provide rural people with a perspective of 'city' life. The impact of such things as the construction (or improvement) of roads, the role of the media, return visits by ex-villagers, and the urban visiting of country people [is] discussed in terms of social urbanization. This presentation renews the call for eschewing bipolar models for studying migration/urbanization in favor of a broader and more holistic perspective. Furthermore, this article suggests that urbanization is another manifestation of a type of dependency relationship." excerpt

[Urban industrial contaminated sites: a new issue in the field of environmental remediation in China].

PubMed

Liao, Xiao-Yong; Chong, Zhong-Yi; Yan, Xiu-Lan; Zhao, Dan

2011-03-01

Contamination of urban industrial lands is a new environmental problem in China during the process of upgrade of industrial structure and adjustment of urban layout. It restricts the safe re-use of urban land resources, and threatens the health of surrounding inhabitants. In the paper, the market potential of contaminated-site remediation was known through analysis of spatial distribution of urban industrial sites in China. Remediation technologies in the Occident which were suitable for urban industrial contaminated sites were discussed and compared to evaluate their superiority and inferiority. And then, some advices of remediation technologies for urban industrial contaminated sites in China were proposed.

[Preliminary Study on Linear Alkylbenzenes as Indicator for Process of Urbanization].

PubMed

Xu, Te; Zeng, Hui; Ni, Hong-Gang

2016-01-15

In this study, we selected Shenzhen City as a typical region of urbanization and took Linear alkylbenzenes ( LABs) as an environmental molecular marker to investigate the relationship between soil LABs levels and urbanization indexes on the basis of analysis of spatial distribution of LABs in surface soil. Our results indicated relations between the LABs levels in soil and the five urbanization indexes, such as the population, water supply, urban construction, income and expenditure, as well as industrial structure. These results suggested that LABs levels were correlated with urbanization and could be used as an environmental molecular indicator for the process of urbanization.

Assessing the effects of the Great Eastern China urbanization on the East Asian summer monsoon by coupling an urban canopy model with a Regional Climate Model

NASA Astrophysics Data System (ADS)

Liu, Z.; Xue, Y.; Liu, S.; Oleson, K. W.

2012-12-01

The urbanization causes one of the most significant land cover changes. Especially over the eastern China from Beijing to Shanghai, the great urbanization occurs during the past half century.It modifies the physical characteristics of land surface, including land surface albedo, surface roughness length and aerodynamicresistanceand thermodynamic conduction over land. All of these play very important role in regional climate change. Afteremploying several WRF/Urban models to tests land use and land cover change(LUCC) caused by urbanization in East Asia, we decided to introducea urban canopy submodule,the Community Land surface Model urban scheme(CLMU)to the WRF and coupled with the WRF-SSiB3 regional climate model. The CLMU and SSIB share the similar principal to treat the surface energy and water balances and aerodynamic resistance between land and atmosphere. In the urban module, the energy balances on the five surface conditions are considered separately: building roof, sun side building wall, shade side building wall, pervious land surface and impervious road. The surface turbulence calculation is based on Monin-Obukhov similarity theory. We have made further improvements for the urban module. Over each surface condition, a method to calculate sky view factor (SVF) is developed based on the physically process while most urban models simply provide an empirical value for SVF. Our approach along with other improvement in short and long wave radiation transfer improves the accuracy of long-wave and shortwave radiation processing over urban surface. The force-restore approximation is employed to calculate the temperature of each outer surfaces of building. The inner side temperature is used as the restore term and was assigned as a tuning constant. Based on the nature of the force-restore method and our tests, we decide to employ the air mean temperature of last 72 hours as a restore term, which substantially improve the surface energy balance. We evaluate the ability of the newly coupled model by two runs: one without and one with the urban canopy module. The coupled model is integrated from March through September, covering a summer monsoon season. The preliminary results show more significant urban heat island (UHI) effect over urban areas with the urban canopy model. The existence of the UHIs enhances the convection in lower atmosphere, affects the water vapor transportation and precipitation of the surrounding area, consistent with the phenomena that occur in urban areas. We further test the effect of urbanization on the monsoon by introducing two maps, one with and one without urbanization and the effect of the urbanization on the monsoon evolution and low level circulation will be discussed in the presentation.

Urbanization and environmental change during the economic transition on the Mongolian Plateau: Hohhot and Ulaanbaatar.

PubMed

Fan, Peilei; Chen, Jiquan; John, Ranjeet

2016-01-01

Driven by drastic socioeconomic changes in China and Mongolia, urbanization has become one of the most significant driving forces in the transformation of the Mongolian Plateau in the past 30 years. Using Hohhot and Ulaanbaatar as case studies, we developed a holistic approach to examine the socioeconomic and natural driving forces for urbanization and to investigate the impact on the urban environment. We used a multidisciplinary approach and relied on a variety of data sources to assess the changes of the landscape and environment of the two cities. We detected a rapid urbanization in Hohhot and Ulaanbaatar, both in terms of urban population growth and urban land expansion, from 1990 to 2010, with a much faster speed in 2000-2010. The local geo-physical conditions have constrained the spatial direction of expansion. Ulaanbaatar lagged behind Hohhot for about a decade when measured by indicators of urban population and urban land. Both cities have a degraded urban environment and a growing air pollution epidemic. While Hohhot had worse air pollution than Ulaanbaatar in the early 2000s, the gap between the two cities became smaller after 2010. The research presented here highlights the following as key determinants for urbanization and environmental change: (1) the co-evolution of urbanization, economic development, and environmental change; (2) the urbanization of transitional economies driven by the change of the economic structure, i.e., the development by both manufacturing and tertiary sectors and the change in the primary sector; and (3) the recent institutional changes and increased integration with the global economy. Copyright © 2015 Elsevier Inc. All rights reserved.

[Delineation of urban development boundary based on the combination of rigidity and elasti-city: A case of Yiwu City in Zhejiang Province, China.

PubMed

Qiu, Si Qi; Yue, Wen Ze

2018-05-01

Under the background of rapid urbanization, we took the contradiction between the rapid urbanization and resource environment protection as the starting point, conducted some theoretical research on urban growth boundary. Based on the definition of urban development boundary, we took Yiwu City, Zhejiang Province as a typical instance. Firstly, this study delimited the ecological boundary as ecological basic constraint area, using the methods of ecological red line discrimination and ecological sensitivity evaluation. Furthermore, the MCE-CA model was used in simulating the city size in 2020, making some adjustments to the moderate and low ecological-sensitive areas in the eco-sensitivity assessing, and delimiting the size of urban growth boundary and elastic control zones. The results showed that the ecological constraint area with a total area of385.2 km 2 and outside of the ecological boundary was the security line of urban development and construction. The urban growth boundary with a total area of 163.3 km 2 was not only the spatial boundary that could be constructed now, but also could meet the future development and construction. The district between the ecological boundary and urban growth boundary was an elastic control zone, in which urban development activities were allowed, but the size of construction could not exceed 8.5% of the total urban development boundary area. Our results delimited the urban development boundary under the rigidity and elasticity, which could guide the urban space development and provide a theoretical reference for China.

Bringing sexual and reproductive health in the urban contexts to the forefront of the development agenda: the case for prioritizing the urban poor.

PubMed

Mberu, Blessing; Mumah, Joyce; Kabiru, Caroline; Brinton, Jessica

2014-09-01

Estimates suggest that over 90 % of population increase in the least developed countries over the next four decades will occur in urban areas. These increases will be driven both by natural population growth and rural-urban migration. Moreover, despite its status as the world's least urbanized region, the urban population in the sub-Saharan Africa region is projected to increase from under 40 % currently to over 60 % by 2050. Currently, approximately 70 % of all urban residents in the region live in slums or slum-like conditions. Sexual and reproductive health (SRH) risks for the urban poor are severe and include high rates of unwanted pregnancies, sexually transmitted infections, and poor maternal and child health outcomes. However, the links between poverty, urbanization, and reproductive health priorities are still not a major focus in the broader development agenda. Building on theoretical and empirical data, we show that SRH in urban contexts is critical to the development of healthy productive urban populations and, ultimately, the improvement of quality of life. We posit that a strategic focus on the sexual and reproductive health of urban residents will enable developing country governments achieve international goals and national targets by reducing health risks among a large and rapidly growing segment of the population. To that end, we identify key research, policy and program recommendations and strategies required for bringing sexual and reproductive health in urban contexts to the forefront of the development agenda.

Surface water areas significantly impacted 2014 dengue outbreaks in Guangzhou, China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tian, Huaiyu; Huang, Shanqian

Dengue transmission in urban areas is strongly influenced by a range of biological and environmental factors, yet the key drivers still need further exploration. To better understand mechanisms of environment–mosquito–urban dengue transmission, we propose an empirical model parameterized and cross-validated from a unique dataset including viral gene sequences, vector dynamics and human dengue cases in Guangzhou, China, together with a 36-year urban environmental change maps investigated by spatiotemporal satellite image fusion. The dengue epidemics in Guangzhou are highly episodic and were not associated with annual rainfall over time. Our results indicate that urban environmental changes, especially variations in surface areamore » covered by water in urban areas, can substantially alter the virus population and dengue transmission. The recent severe dengue outbreaks in Guangzhou may be due to the surge in an artificial lake construction, which could increase infection force between vector (mainly Aedes albopictus) and host when urban water area significantly increased. Impacts of urban environmental change on dengue dynamics may not have been thoroughly investigated in the past studies and more work needs to be done to better understand the consequences of urbanization processes in our changing world. - Highlights: • Urban dengue outbreak is associated with water area in Guangzhou, 1978–2014. • Surface water area can alter population size of dengue virus in urban area. • Urban dengue outbreak is not associated with annual rainfall in Guangzhou. • Spatiotemporal satellite image fusion can investigate urban environmental change. • Urban environmental change could induce virus, vector, and dengue epidemic change.« less

Rural:urban inequalities in post 2015 targets and indicators for drinking-water.

PubMed

Bain, R E S; Wright, J A; Christenson, E; Bartram, J K

2014-08-15

Disparities in access to drinking water between rural and urban areas are pronounced. Although use of improved sources has increased more rapidly in rural areas, rising from 62% in 1990 to 81% in 2011, the proportion of the rural population using an improved water source remains substantially lower than in urban areas. Inequalities in coverage are compounded by disparities in other aspects of water service. Not all improved sources are safe and evidence from a systematic review demonstrates that water is more likely to contain detectable fecal indicator bacteria in rural areas. Piped water on premises is a service enjoyed primarily by those living in urban areas so differentiating amongst improved sources would exacerbate rural:urban disparities yet further. We argue that an urban bias may have resulted due to apparent stagnation in urban coverage and the inequity observed between urban and peri-urban areas. The apparent stagnation at around 95% coverage in urban areas stems in part from relative population growth - over the last two decades more people gained access to improved water in urban areas. There are calls for setting higher standards in urban areas which would exacerbate the already extreme rural disadvantage. Instead of setting different targets, health, economic, and human rights perspectives, We suggest that the focus should be kept on achieving universal access to safe water (primarily in rural areas) while monitoring progress towards higher service levels, including greater water safety (both in rural and urban areas and among different economic strata). Copyright © 2014 Elsevier B.V. All rights reserved.

An Assessment of the Impact of Urbanization on Soil Erosion in Inner Mongolia

PubMed Central

Xiao, Yi; Rao, En-Ming; Jiang, Ling; Xiao, Yang; Ouyang, Zhi-Yun

2018-01-01

Inner Mongolia, an autonomous region of the People’s Republic of China, has experienced severe soil erosion following a period of rapid economic development and urbanization. To investigate how urbanization has influenced the extent of soil erosion in Inner Mongolia, we used urbanization and soil erosion data from 2000 through 2010 to determine the relationship between urbanization and soil erosion patterns. Two empirical equations—the Revised Universal Soil Loss Equation (RUSLE) and the Revised Wind Erosion Equation (RWEQ)—were used to estimate the intensity of soil erosion, and we performed backward linear regression to model how it changed with greater urbanization. There was an apparent increase in the rate of urbanization and a decrease in the area affected by soil erosion in 2010 compared to the corresponding values for 2000. The urban population stood at 11.32 million in 2010, which represented a 16.47% increase over that in 2000. The area affected by soil erosion in 2000 totaled 704,817 km2, yet it had decreased to 674,135 km2 by 2010. However, a path of modest urban development (rural–urban mitigation) and reasonable industrial structuring (the development of GDP-2) may partially reduce urbanization’s ecological pressure and thus indirectly reduce the threat of soil erosion to human security. Therefore, to better control soil erosion in Inner Mongolia during the process of urbanization, the current model of economic development should be modified to improve the eco-efficiency of urbanization, while also promoting new modes of urbanization that are environmentally sustainable, cost-effective, and conserve limited resources. PMID:29562707

Urban population growth and urbanization in the Caribbean.

PubMed

Hope, K R

1985-01-01

The structure, sources, consequences, and policy implications of urbanization and of the rapid growth of the urban population in the Caribbean are examined. In particular, a comparative analysis of the situation in Barbados, Guyana, Jamaica, and Trinidad and Tobago is presented. Data are from a variety of secondary sources, including those published by the United Nations and the World Bank. The need to reorient policies to favor rural rather than urban areas in order to reduce rural-urban migration is noted.

The President's 1978 National Urban Policy Report; A Biennial Report to the Congress Submitted Pursuant to Sections 702 and 703(a), National Urban Policy and New Communities Development Act, as Amended in 1977.

ERIC Educational Resources Information Center

Department of Housing and Urban Development, Washington, DC.

This report describes the process of drawing up a national urban policy, summarizes the views presented at various forums, and sketches much of the data and analyses relied upon by urban policymakers. Part I summarizes the process of American urbanization leading to the emergence of a new stage in urban development. Part II describes changing…

Analysis of Urban Terrain Data for Use in the Development of an Urban Camouflage Pattern

DTIC Science & Technology

1990-02-01

the entire lightness gamut , but concentrated in the red, orange, yellow and neutral regions of color space. 20. DISTRIBUTION I AVAILABILITY OF...le·nents grouped by color. ) Summary of Scenes Filmed for Urban Camouflage Study. 01Jtirnum Number of Do·nains Separated by Type; Sele:::ted CIELAB ...Values for All Urban Scenes. Selected CIELAB Values for Type I Urban Scenes. Selected CIELAB Values for Type II Urban Scenes. v Page 3 6 7 8 9

Urban-rural differences in the gene expression profiles of Ghanaian children.

PubMed

Amoah, A S; Obeng, B B; May, L; Kruize, Y C; Larbi, I A; Kabesch, M; Wilson, M D; Hartgers, F C; Boakye, D A; Yazdanbakhsh, M

2014-01-01

Recent studies indicate that urbanization is having a pronounced effect on disease patterns in developing countries. To understand the immunological basis of this, we examined mRNA expression in whole blood of genes involved in immune activation and regulation in 151 children aged 5-13 years attending rural, urban low socioeconomic status (SES) and urban high-SES schools in Ghana. Samples were also collected to detect helminth and malaria infections. Marked differences in gene expression were observed between the rural and urban areas as well as within the urban area. The expression of both interleukin (IL)-10 and programmed cell death protein 1 increased significantly across the schools from urban high SES to urban low SES to rural (P-trend <0.001). Although IL-10 gene expression was significantly elevated in the rural compared with the urban schools (P<0.001), this was not associated with parasitic infection. Significant differences in the expression of toll-like receptors (TLRs) and their signaling genes were seen between the two urban schools. Genetic differences could not fully account for the gene expression profiles in the different groups as shown by analysis of IL-10, TLR-2 and TLR-4 gene polymorphisms. Immune gene expression patterns are strongly influenced by environmental determinants and may underlie the effects of urbanization seen on health outcomes.

Dominant control of agriculture and irrigation on urban heat island in India.

PubMed

Kumar, Rahul; Mishra, Vimal; Buzan, Jonathan; Kumar, Rohini; Shindell, Drew; Huber, Matthew

2017-10-25

As is true in many regions, India experiences surface Urban Heat Island (UHI) effect that is well understood, but the causes of the more recently discovered Urban Cool Island (UCI) effect remain poorly constrained. This raises questions about our fundamental understanding of the drivers of rural-urban environmental gradients and hinders development of effective strategies for mitigation and adaptation to projected heat stress increases in rapidly urbanizing India. Here we show that more than 60% of Indian urban areas are observed to experience a day-time UCI. We use satellite observations and the Community Land Model (CLM) to identify the impact of irrigation and prove for the first time that UCI is caused by lack of vegetation and moisture in non-urban areas relative to cities. In contrast, urban areas in extensively irrigated landscapes generally experience the expected positive UHI effect. At night, UHI warming intensifies, occurring across a majority (90%) of India's urban areas. The magnitude of rural-urban temperature contrasts is largely controlled by agriculture and moisture availability from irrigation, but further analysis of model results indicate an important role for atmospheric aerosols. Thus both land-use decisions and aerosols are important factors governing, modulating, and even reversing the expected urban-rural temperature gradients.

Towards the new urban agenda of safe cities: urban crimes in four Indonesian cities

NASA Astrophysics Data System (ADS)

Setiawan, B.

2017-12-01

As has stated in the Habitat III agreement, named as The New Urban Agenda/NUA, signed in Quito, Ecuador, October 2016, safe cities is one among important global goals that should be achieved in the next twenty years - safe city is defined generally by city that is equated with reduced violence on the one hand, and on the other, with reduced uncertainty. The fact that under a rapid urbanization and urban transformation in Indonesia, urban crimes tend to increase in many Indonesian cities questions whether Indonesian cities are ready to ensure the idea of safe city. This paper aims to document the incidents of urban crimes, spatial dimensions, the socio-factors and how local community responses to such crimes. It utilised a multiple case studies of four cities in Indonesia which are: Yogyakarta, Surabaya, Makasar, and Manado, Data and information for the paper were primarily collected through secondary data, but some field observations and interviews with stakeholders related to urban crimes in four cities were also conducted. The paper could be considered as a preliminary study to understand the urban crimes phenomena in Indonesia and finds that the incidents of urban crimes are fluctuated in four cities explored. It argues that there is a significant correlation between urban crimes incidents and spatial characteristics of the city.

Trends in childhood mortality in Kenya: the urban advantage has seemingly been wiped out.

PubMed

Kimani-Murage, E W; Fotso, J C; Egondi, T; Abuya, B; Elungata, P; Ziraba, A K; Kabiru, C W; Madise, N

2014-09-01

We describe trends in childhood mortality in Kenya, paying attention to the urban-rural and intra-urban differentials. We use data from the Kenya Demographic and Health Surveys (KDHS) collected between 1993 and 2008 and the Nairobi Urban Health and Demographic Surveillance System (NUHDSS) collected in two Nairobi slums between 2003 and 2010, to estimate infant mortality rate (IMR), child mortality rate (CMR) and under-five mortality rate (U5MR). Between 1993 and 2008, there was a downward trend in IMR, CMR and U5MR in both rural and urban areas. The decline was more rapid and statistically significant in rural areas but not in urban areas, hence the gap in urban-rural differentials narrowed over time. There was also a downward trend in childhood mortality in the slums between 2003 and 2010 from 83 to 57 for IMR, 33 to 24 for CMR, and 113 to 79 for U5MR, although the rates remained higher compared to those for rural and non-slum urban areas in Kenya. The narrowing gap between urban and rural areas may be attributed to the deplorable living conditions in urban slums. To reduce childhood mortality, extra emphasis is needed on the urban slums. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Do wild-caught urban house sparrows show desensitized stress responses to a novel stressor?

PubMed

Salleh Hudin, Noraine; Teyssier, Aimeric; Aerts, Johan; Fairhurst, Graham D; Strubbe, Diederik; White, Joël; De Neve, Liesbeth; Lens, Luc

2018-04-09

While urbanisation exposes individuals to novel challenges, urban areas may also constitute stable environments in which seasonal fluctuations are buffered. Baseline and stress-induced plasma corticosterone levels are often found to be similar in urban and rural populations. Here we aimed to disentangle two possible mechanisms underlying such pattern: (i) urban environments are no more stressful or urban birds have a better ability to habituate to stressors; or (ii) urban birds developed desensitized stress responses. We exposed wild-caught urban and rural house sparrows ( Passer domesticus ) to combined captivity and diet treatments (urban vs rural diet) and measured corticosterone levels (cort f ) both in natural tail feathers and in regrown homologous ones. Urban and rural house sparrows showed similar cort f levels in the wild and in response to novel stressors caused by the experiment, supporting the growing notion that urban environments are no more stressful during the non-breeding season than are rural ones. Still, juveniles and males originating from urban populations showed the highest cort f levels in regrown feathers. We did not find evidence that cort f was consistent within individuals across moults. Our study stresses the need for incorporating both intrinsic and environmental factors for the interpretation of variation in cort f between populations. © 2018. Published by The Company of Biologists Ltd.

Research on monocentric model of urbanization by agent-based simulation

NASA Astrophysics Data System (ADS)

Xue, Ling; Yang, Kaizhong

2008-10-01

Over the past years, GIS have been widely used for modeling urbanization from a variety of perspectives such as digital terrain representation and overlay analysis using cell-based data platform. Similarly, simulation of urban dynamics has been achieved with the use of Cellular Automata. In contrast to these approaches, agent-based simulation provides a much more powerful set of tools. This allows researchers to set up a counterpart for real environmental and urban systems in computer for experimentation and scenario analysis. This Paper basically reviews the research on the economic mechanism of urbanization and an agent-based monocentric model is setup for further understanding the urbanization process and mechanism in China. We build an endogenous growth model with dynamic interactions between spatial agglomeration and urban development by using agent-based simulation. It simulates the migration decisions of two main types of agents, namely rural and urban households between rural and urban area. The model contains multiple economic interactions that are crucial in understanding urbanization and industrial process in China. These adaptive agents can adjust their supply and demand according to the market situation by a learning algorithm. The simulation result shows this agent-based urban model is able to perform the regeneration and to produce likely-to-occur projections of reality.

Shifting the urban heat island clock in a megacity: a case study of Hong Kong

NASA Astrophysics Data System (ADS)

Chen, Xuan; Jeong, Su-Jong

2018-01-01

With increasing levels of urbanization in the near future, understanding the impact of urbanization on urban heat islands (UHIs) is critical to adapting to regional climate and environmental changes. However, our understanding of the UHI effect relies mainly on its intensity or magnitude. The present study evaluates the impact of urbanization on UHI duration changes by comparing three stations with different rates of urbanization, including highly developed and developing urban areas throughout Hong Kong, from 1990-2015. Results show that the 26 year average UHI intensity in highly urbanized regions is much higher than that in developing areas, and the 26 year average of UHI duration is similar. Over the past 25 years, however, UHI duration has increased only in developing urban areas, from 13.59-17.47 hours. Both earlier UHI starting and later UHI ending times concurrently contribute to the UHI effect being experienced for a longer duration. The differences in UHI duration change between the two areas are supported by population and by night light changes from space. Increasing night light, which suggests enhancements in the economic infrastructure, occurred only in the developing urban areas. Our results suggest that changes in UHI duration should be included in an assessment of regional climate change as well as in urban planning in a megacity.

Contributions to Global Augmented Compound Urban Heat Extreme (ACUTE) from Climate Change and the Urban Heat Island Effect

NASA Astrophysics Data System (ADS)

Huang, K.

2017-12-01

Over the next decades, climate change is projected to increase the intensity and frequency of extreme heat events (EHEs). The severity and periodicity of these hazards are likely to be further compounded by stronger urban heat island (UHI) effects as the world continues to urbanize. However, there is little known about how greenhouse gases (GHG) induced changes in EHE will interact with UHI, and what this will mean for the exposure of urban populations to high temperature. This work aims to fill this knowledge gap by combining a mesoscale meteorological model (Weather Research Forecasting, WRF) with a global urban expansion forecast, to generate spatially explicit projections of compound urban temperature extremes through 2050. These global projections include all the urban areas in developing world. The respective contributions from GHG-induced climate change, the UHI effect, and their interaction vary across different types of urban areas. The resulting compound heat extremes will be more intense and frequent in emerging Asian and African mega urban regions, located in tropical/subtropical climates, due to their unprecedented sizes and the significantly reduced evaporation. Previous studies neglecting the interaction between global climate change and regional UHI effect have underestimated exposure to heat extremes in urban areas.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, zhifeng; He, Chunyang; Zhou, Yuyu

Urbanization has transformed the world’s landscapes, resulting in a series of ecological and environmental problems. To assess urbanization impacts and improve sustainability, one of the first questions that we must address is: how much of the world’s land has been urbanized? Unfortunately, the estimates of the global urban land reported in the literature vary widely from less than 1% to 3% primarily because different definitions of urban land were used. To evade confusion, here we propose a hierarchical framework for representing and communicating the spatial extent of the world’s urbanized land at the global, regional, and more local levels. Themore » hierarchical framework consists of three spatially nested definitions: “urban area” that is delineated by administrative boundaries, “built-up area” that is dominated by artificial surfaces, and “impervious surface area” that is devoid of life. These are really three different measures of urbanization. In 2010, the global urban land was close to 3%, the global built-up area was 0.65%, and the global impervious surface area was 0.45%, of the word’s total land area (excluding Antarctica and Greenland). We argue that this hierarchy of urban land measures, in particular the ratios between them, can also facilitate better understanding the biophysical and socioeconomic processes and impacts of urbanization.« less

Simulating the Response of Urban Water Quality to Climate and Land Use Change in Partially Urbanized Basins

NASA Astrophysics Data System (ADS)

Sun, N.; Yearsley, J. R.; Nijssen, B.; Lettenmaier, D. P.

2014-12-01

Urban stream quality is particularly susceptible to extreme precipitation events and land use change. Although the projected effects of extreme events and land use change on hydrology have been resonably well studied, the impacts on urban water quality have not been widely examined due in part to the scale mismatch between global climate models and the spatial scales required to represent urban hydrology and water quality signals. Here we describe a grid-based modeling system that integrates the Distributed Hydrology Soil Vegetation Model (DHSVM) and urban water quality module adpated from EPA's Storm Water Management Model (SWMM) and Soil and water assessment tool (SWAT). Using the model system, we evaluate, for four partially urbanized catchments within the Puget Sound basin, urban water quality under current climate conditions, and projected potential changes in urban water quality associated with future changes in climate and land use. We examine in particular total suspended solids, toal nitrogen, total phosphorous, and coliform bacteria, with catchment representations at the 150-meter spatial resolution and the sub-daily timestep. We report long-term streamflow and water quality predictions in response to extreme precipitation events of varying magnitudes in the four partially urbanized catchments. Our simulations show that urban water quality is highly sensitive to both climatic and land use change.

Comparison of pesticides in eight U.S. urban streams

USGS Publications Warehouse

Hoffman, R.S.; Capel, P.D.; Larson, S.J.

2000-01-01

Little is known of the occurrence of pesticides in urban streams compared to streams draining agricultural areas. Water samples from eight urban streams from across the United States were analyzed for 75 pesticides and seven transformation products. For six of the eight urban streams, paired agricultural streams were used for comparisons. The herbicides detected most frequently in the urban streams were prometon, simazine, atrazine, tebuthiuron, and metolachlor, and the insecticides detected most frequently were diazinon, carbaryl, chlorpyrifos, and malathion. In contrast to similar-sized agricultural streams, total insecticide concentrations commonly exceeded total herbicide concentrations in these urban streams. In general, the temporal concentration patterns in the urban streams were consistent with the characteristics of the local growing season. The insecticides carbaryl and diazinon exceeded criteria for the protection of aquatic life in many of the urban streams in the spring and summer. When the country as a whole is considered, the estimated mass of herbicides contributed by urban areas to streams is dwarfed by the estimated contribution from agricultural areas, but for insecticides, contributions from urban and agricultural areas may be similar. The results of this study suggest that urban areas should not be overlooked when assessing sources and monitoring the occurrence of pesticides in surface waters.

Classified and clustered data constellation: An efficient approach of 3D urban data management

NASA Astrophysics Data System (ADS)

Azri, Suhaibah; Ujang, Uznir; Castro, Francesc Antón; Rahman, Alias Abdul; Mioc, Darka

2016-03-01

The growth of urban areas has resulted in massive urban datasets and difficulties handling and managing issues related to urban areas. Huge and massive datasets can degrade data retrieval and information analysis performance. In addition, the urban environment is very difficult to manage because it involves various types of data, such as multiple types of zoning themes in the case of urban mixed-use development. Thus, a special technique for efficient handling and management of urban data is necessary. This paper proposes a structure called Classified and Clustered Data Constellation (CCDC) for urban data management. CCDC operates on the basis of two filters: classification and clustering. To boost up the performance of information retrieval, CCDC offers a minimal percentage of overlap among nodes and coverage area to avoid repetitive data entry and multipath query. The results of tests conducted on several urban mixed-use development datasets using CCDC verify that it efficiently retrieves their semantic and spatial information. Further, comparisons conducted between CCDC and existing clustering and data constellation techniques, from the aspect of preservation of minimal overlap and coverage, confirm that the proposed structure is capable of preserving the minimum overlap and coverage area among nodes. Our overall results indicate that CCDC is efficient in handling and managing urban data, especially urban mixed-use development applications.

Urban Stream Ecology

EPA Science Inventory

Urban watersheds characteristically have high impervious surface cover, resulting in high surface runoff and low infiltration following storms. In response, urban streams experience “flashy” stormflows, reduced baseflows, bank erosion, channel widening, and sedimentation. Urban ...

CADDIS Volume 2. Sources, Stressors and Responses: Urbanization - Temperature

EPA Pesticide Factsheets

water temperature changes associated with urbanization, heated surface runoff associated with urbanization, how temperature changes associated with urbanization can affect stream biota, interactive effects of urbanizaiton and climate change.

Exploring the response of net primary productivity variations to urban expansion and climate change: a scenario analysis for Guangdong Province in China.

PubMed

Pei, Fengsong; Li, Xia; Liu, Xiaoping; Lao, Chunhua; Xia, Gengrui

2015-03-01

Urban land development alters landscapes and carbon cycle, especially net primary productivity (NPP). Despite projections that NPP is often reduced by urbanization, little is known about NPP changes under future urban expansion and climate change conditions. In this paper, terrestrial NPP was calculated by using Biome-BGC model. However, this model does not explicitly address urban lands. Hence, we proposed a method of NPP-fraction to detect future urban NPP, assuming that the ratio of real NPP to potential NPP for urban cells remains constant for decades. Furthermore, NPP dynamics were explored by integrating the Biome-BGC and the cellular automata (CA), a widely used method for modeling urban growth. Consequently, urban expansion, climate change and their associated effects on the NPP were analyzed for the period of 2010-2039 using Guangdong Province in China as a case study. In addition, four scenarios were designed to reflect future conditions, namely baseline, climate change, urban expansion and comprehensive scenarios. Our analyses indicate that vegetation NPP in urban cells may increase (17.63 gC m(-2) year(-1)-23.35 gC m(-2) year(-1)) in the climate change scenario. However, future urban expansion may cause some NPP losses of 241.61 gC m(-2) year(-1), decupling the NPP increase of the climate change factor. Taking into account both climate change and urban expansion, vegetation NPP in urban area may decrease, minimally at a rate of 228.54 gC m(-2) year(-1) to 231.74 gC m(-2) year(-1). Nevertheless, they may account for an overall NPP increase of 0.78 TgC year(-1) to 1.28 TgC year(-1) in the whole province. All these show that the provincial NPP increase from climate change may offset the NPP decrease from urban expansion. Despite these results, it is of great significance to regulate reasonable expansion of urban lands to maintain carbon balance. Copyright © 2014 Elsevier Ltd. All rights reserved.

Diurnal variations of airborne pollen concentration and the effect of ambient temperature in three sites of Mexico City

NASA Astrophysics Data System (ADS)

Ríos, B.; Torres-Jardón, R.; Ramírez-Arriaga, E.; Martínez-Bernal, A.; Rosas, I.

2016-05-01

Pollen is an important cause of allergic respiratory ailments in the Mexico City Metropolitan Area (MCMA). However, very little is known if ambient air temperature correlates with the early blooming of plants observed in other urban areas around the world. A research study was conducted during the dry season of 2012-2013 at three representative sites of the MCMA with different urban characteristics with the aim to understand the relationships between the profusion and diversity of pollen against temperature and other meteorological variables and degree of urbanization. Pollen samples were collected using a Hirst-type trap sampler in the sites: Merced (highly urbanized), Iztapalapa (medium-high urbanized) and Coyoacan (moderately urbanized). Urbanization levels were determined using a composite index based on population density, proportion of surface covered by construction and asphalt, and urban heat island intensity. A set of representative pollen sampling tapes were assayed under a light microscope at magnification of ×1,000 and converted to grains per cubic meter. The most representative pollen types found in the three sites were, regardless of urbanization levels were: Fraxinus, Cupressaceae/Taxodiaceae, Casuarina, Alnus, Myrtaceae, and Pinus. Total pollen concentration was greatest in the moderately urbanized area, although earlier blooming took place at the highly urbanized zone. Total pollen concentration in the medium-high urbanized site has the lowest because the green areas in this zone of MCMA are few. In a diurnal basis, the most abundant pollen types peaked near midday or in the afternoon evening at the three sites. A Spearman test showed a positive correlation among bihourly pollen concentrations, temperature and relative humidity in all sites, but wind speed just correlated in Iztapalapa and Coyoacan. The results obtained suggest that Urban Heat Island Intensity can disturb flowering periods and pollen concentrations, largely in the highly urbanized areas. A principal components analysis established that the concentrations of each pollen type differed across the urbanization gradients. Additionally, it was found that a large number of allergenic pollens are produced by ornamental trees, some only recently introduced by urban planners.

Urban and Suburban Influences on Water Chemistry in Washington DC: Impervious Surfaces and Urban Stream Syndrome

NASA Astrophysics Data System (ADS)

MacAvoy, S. E.; Petersen, E.

2015-12-01

Among the challenges facing urban rivers are water stormwater runoff problems and changing water chemistry, not only from air and water pollution sources, but also from altered geology with the development of "urban karst". Seventy five percent of the Anacostia River in Washington, D.C. is urban or impervious. The Anacostia River experiences environmental challenges similar to those of other urban industrial rivers (heavy metal, PCB and PAH contamination). It also has Ca/Sr ratios above 200, and Na concentrations higher than Ca, and elevated ionic strength, all associated with extended chemical interaction with concrete. While these chemical characteristics have been documented in the urban areas within DC, they have not been examined in the largely suburban/mixed development tributaries of the Anacostia. Here we examine the base-flow geochemistry of the Anacostia River and its suburban tributaries (6 locations) over a year (November 2014- August 2015), concentrating on the following water chemistry variables: pH, hardness, SAR, alkalinity, Ca, Mg, Na, K, Fe, Mn, Zn, Al, Ba, Ni, total P, S, Sr, NO3-, NH4+, PO43-. NO3- and NH4+ were generally lowest in at all sites in January, but rose to between 0.5 and 2.4 mg/L in June, with highest NO3- concentrations in suburban areas. Na and Cl concentrations were 5x higher in suburban areas than urban areas during the winter months. Ca/Sr concentration ratios, were between 120 and 200 for suburban sites but increased as the sites became more urban (to a high of 240 for the most urban site). These trends have been observed in other urban streams, and correlate with percent impervious area. The data follow patterns expected for "urban stream syndrome" and dissolution of concrete. Suburban areas, with their relatively small streams, show greater winter salting effects than more urban areas down stream. Suburban areas also show higher NO3- (and occasionally higher NH4+) than urban areas except in winter. The data presented here demonstrates that the geochemistry of highly urbanized systems may be significantly altered and should be better understood in order to assess urban impacts on water quality.

Urban Land Cover/use Change Detection Using High Resolution SPOT 5 and SPOT 6 Images and Urban Atlas Nomenclature

NASA Astrophysics Data System (ADS)

Akay, S. S.; Sertel, E.

2016-06-01

Urban land cover/use changes like urbanization and urban sprawl have been impacting the urban ecosystems significantly therefore determination of urban land cover/use changes is an important task to understand trends and status of urban ecosystems, to support urban planning and to aid decision-making for urban-based projects. High resolution satellite images could be used to accurately, periodically and quickly map urban land cover/use and their changes by time. This paper aims to determine urban land cover/use changes in Gaziantep city centre between 2010 and 2105 using object based images analysis and high resolution SPOT 5 and SPOT 6 images. 2.5 m SPOT 5 image obtained in 5th of June 2010 and 1.5 m SPOT 6 image obtained in 7th of July 2015 were used in this research to precisely determine land changes in five-year period. In addition to satellite images, various ancillary data namely Normalized Difference Vegetation Index (NDVI), Difference Water Index (NDWI) maps, cadastral maps, OpenStreetMaps, road maps and Land Cover maps, were integrated into the classification process to produce high accuracy urban land cover/use maps for these two years. Both images were geometrically corrected to fulfil the 1/10,000 scale geometric accuracy. Decision tree based object oriented classification was applied to identify twenty different urban land cover/use classes defined in European Urban Atlas project. Not only satellite images and satellite image-derived indices but also different thematic maps were integrated into decision tree analysis to create rule sets for accurate mapping of each class. Rule sets of each satellite image for the object based classification involves spectral, spatial and geometric parameter to automatically produce urban map of the city centre region. Total area of each class per related year and their changes in five-year period were determined and change trend in terms of class transformation were presented. Classification accuracy assessment was conducted by creating a confusion matrix to illustrate the thematic accuracy of each class.

City and Urbanity in the Social Discourse

NASA Astrophysics Data System (ADS)

Dymnicka, Małgorzata; Badach, Joanna

2017-10-01

The aim of our article is an attempt to present the concept of urbanity that has been shaped throughout centuries along with the development of European civilisation and now entered a new phase of social production of space based on cultural dimensions. The future of the majority of World’s population is connected currently with the urban life with the assumption that qualitative characteristics of life in the 21st century define the quality of civilisation itself. Contrary to many scientists’ predictions of the decline of the city and urbanity, new reviving urban projects, social local activities and everyday urbanism appear which are connected with redefinition of the city as a community. The rebirth of cities, currently referred to as “urban renaissance”, “urban resurgence” or “urban revival”, can be also defined in terms of new urbanity regarded as an insightful and creative attitude towards the city and its culture. The elementary order of things was determined in the last decades not by the space but by the time and its acceleration and simultaneously the role of architecture alters. The course of thinking about the city is changing from a single space-time city towards a personalised city, based on individual identities and corresponding places in the physical and virtual space. That can mean a new role of the city in the creation of urbanity. In the era of advanced communication technologies, a question arises about the ontological status of the city when the emphasis is placed on independence and individuality in interactions between people. Social life becomes detached from traditional spatial patterns and practices. We are interested in the urbanity understood in the wider context of cultural urban studies which are focused on new ways of organising the communication space and social relations. We will refer in this article to the values constitutive for the city and urbanity that guided the idea of the city since the dawn of time as well as its new deconstructed forms (e.g. the pop-up city, neo-bohemia, the creative class, neighbour communities, urban guerrilla gardening, experimental urban farms, etc.).

Urban Environmental Education for Global Transformation Initiatives - Integrating Information and Communication Systems for Urban Sustainability in 2050.

NASA Astrophysics Data System (ADS)

Chaudhari, K.

2017-12-01

The Urban population of developing countries is predicted to rise from one third in 1990 to over 50% by 2025. In 1950 the world's total urban population was 734 million, of whom 448 million were living in developed countries and remaining 286 were in developing region. The total population on earth is predicted to increase by more than one billion people within the next 15 years, reaching 8.5 billion in 2030, and to increase further to 9.7 billion in 2050 and 11.2 billion by 2100. Looking at the ever increasing urbanization.In 2016, an estimated 54.5 per cent of the world's populations inhabited in urban region. By 2030, urban areas are projected to shelter 60 per cent of people worldwide and one in every three people will live in cities with at least half a million inhabitants.On the basis of these figures and other global trends, it would appear that Africa and Asia will have the highest share of world's urban growth in next 25 years, resulting consideration rise of large number of metropolitan cities and towns. Therefore issues related to urban climate change will be important for socio economic development for urban transformation through environmental sustainability.The information and communication systems plays an important role in achieving the social sustainability through environmental sustainability for urban transformation. This presentation aims to start the Global initiatives on the problem identifications in environment education for global transformation, education for socio-economic and environmental sustainability due to urbanization in 2050 to investigate problems related to social-economic risks and management issues resulting from urbanization to aid mitigation planning in globalized world and to educate scientists and local populations to form a basis for sustainable solutions in environment learning.The presentation aims to assess the potential of information and communication technology for environment education,both within different societies and internationally for urban climate sustainability and global transformation for sustainable urban development. The presentation aims at building the global network of environment education organisations for effective application of information and communication technologies for Urban cliamte sustainability in 2050.

[The urbanized societies of Latin America and the Caribbean: some dimensions and observations].

PubMed

Ebanks, G E

1993-06-01

A demographic perspective on urbanization patterns in Latin America and the Caribbean is provided. The level and rate of urbanization and the hierarchies of urban places are considered, along with the determinants and consequences of these trends. Latin America and the Caribbean are the most urbanized of the developing regions, with almost 70% of the population classified as urban in 1991. Most Latin American and Caribbean countries have rural populations capable of maintaining continuous growth of the urban population for some time through internal migration and reclassification of localities. Latin American societies are urban in nature, and it is unlikely that decentralization and deconcentration policies will have significant repercussions. The Latin American urban population is estimated to have increased from 164 million in 1970 to 320 million in 1990, while the rural population increased from 122 to 128 million in the same years. Most governments of the region are preoccupied by the size of the urban population. There are too many urban residents to be absorbed in productive activities, but all require public services generally financed through taxation. The small tax bases result in frequent decisions to finance services through deficit spending. The size of the population and the level of urbanization may not be the principal agents of ecological deterioration or the greatest obstacles to development, but they play a significant role in these problems. Incorporating millions of urban residents into the productive sector of the economy is an important challenge for the development of these societies. The urban population in Latin America and the Caribbean is expected to continue growing at significant rates until well into the next century. In most countries of the region, internal migration accounted for 30-40% of urban growth between 1950 and 1970, but its contribution loses importance as the level of urbanization exceeds 70% or so. The number of urban places as well as the sizes of cities have been increasing. From the end of World War II to the 1970s, the principal urban centers grew most rapidly, but in the 1980s and early 1990s the medium sized cities experienced the most rapid growth. Latin America and the Caribbean are a region of high urban primacy, in which one city, generally the capital, is several times larger than the second city or cities. Mexico City, Sao Paulo, Buenos Aires, and Rio de Janeiro are megalopolises. Latin America's population is excessively concentrated in three ways: into urban localities, into a small area of the national territory, and into megalopolises. Excessive concentration is associated with severe environmental problems. Most have possible solutions, but costs will be high and great political will is required. The quality of life is poor for a large segment of urban dwellers and poverty is pervasive. Urgent action is needed to improve the quality of life and protect the environment.

A National Assessment of the Urban Forest: An Overview

Treesearch

John F. Dwyer; David J. Nowak

2000-01-01

Urban forest management promises to play a critical role in the management of .... our nation's forest resources in the 21st century. Urban forests are significant and diverse ecosystems with intricate connections among their physical, biological, and social components; as well as with other elements of urban and natural resource systems. Urban forests are also...

Positive effects of afforestation efforts on the health of urban soils

Treesearch

Emily E. Oldfield; Alexander J. Felson; Stephen A. Wood; Richard A. Hallett; Michael S. Strickland; Mark A. Bradford

2014-01-01

Large-scale tree planting projects in cities are increasingly implemented as a strategy to improve the urban environment. Trees provide multiple benefits in cities, including reduction of urban temperatures, improved air quality, mitigation of storm-water run-off, and provision of wildlife habitat. How urban afforestation affects the properties and functions of urban...

Urban Pre-Service K-6 Teachers' Conceptions of Citizenship and Civic Education: Weighing the Risks and Rewards

ERIC Educational Resources Information Center

Marri, Anand R.; Michael-Luna, Sara; Cormier, Maria Scott; Keegan, Patrick

2014-01-01

To effectively help urban pre-service teachers to provide civic education opportunities in their future classrooms, teacher educators should know how urban pre-service teachers themselves conceptualize citizenship and civic engagement. Through the research question--how do urban K-6 pre-service teachers currently enrolled in an urban education…

Advancing an Urban Mission: The West Baltimore Pre-K to 16 Urban Education Corridor

ERIC Educational Resources Information Center

Arrington, Pamela Gray

2006-01-01

Coppin State University is committed to meeting the educational needs of its urban population and improving the quality of life in its urban community. An institutional pioneer in urban education, Coppin State University is the first higher education institution in the state to assume responsibility for the restructuring and administration of a…

Intellectually Gifted Rural-to-Urban Migrant Children's Attention

ERIC Educational Resources Information Center

Zhang, Hui; He, Yunfeng; Tao, Ting; Shi, Jian-Nong

2016-01-01

The term "intellectually gifted rural-to-urban migrant children" refers to intellectually gifted children who are in migration from rural to urban areas. We compared performances on seven attention tasks among intellectually gifted (n = 26) and average (n = 30) rural-to-urban migrant and intellectually gifted urban children (n = 31). Our…

Becoming an Insider: Teaching Science in Urban Settings

ERIC Educational Resources Information Center

Calabrese Barton, Angela; Berchini, Christina

2013-01-01

The discourse of urban science education is often framed by discussions of achievement gaps and limited resources. Although these realities are part of the urban education landscape, they focus on deficits--what urban youth and their teachers and schools lack. We argue that it is more productive to frame urban science education as a function of…

Urban Environmental Education Project, Curriculum Module III: Urban Transportation - Where Are We Going?

ERIC Educational Resources Information Center

Bell, Ellen

Included in this module are five activities dealing with modes of transportation in the urban environment. The activities include: (1) a discussion of transportation considerations in urban areas; (2) discussion of bikeways and their desirability in the urban environment; (3) the bikeway and the environment; (4) designing a bikeway; and (5)…

34 CFR 636.31 - How does the Secretary establish a network of urban grant institutions?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 3 2011-07-01 2011-07-01 false How does the Secretary establish a network of urban... Institutions Network? § 636.31 How does the Secretary establish a network of urban grant institutions? (a) The Secretary establishes a network of urban grant institutions consisting of the urban grant institutions...

34 CFR 636.31 - How does the Secretary establish a network of urban grant institutions?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false How does the Secretary establish a network of urban... Institutions Network? § 636.31 How does the Secretary establish a network of urban grant institutions? (a) The Secretary establishes a network of urban grant institutions consisting of the urban grant institutions...

Trends and patterns of urbanization in Egypt during the 1966-1976 intercensal period.

PubMed

Morcos, W S

1980-01-01

The author analyzes the decline in the rate of urbanization and the effects of this decline on traditional patterns of urbanization in Egypt between 1966 and 1976. Trends and patterns of urbanization in the twentieth century are briefly examined. National policies and their effects on urbanization patterns are reviewed (SUMMARY IN ARA)

Biophysical control of whole tree transpiration under an urban environment in Northern China

Treesearch

Lixin Chen; Zhiqiang Zhang; Zhandong Li; Jianwu Tang; Peter Caldwell; et al

2011-01-01

Urban reforestation in China has led to increasing debate about the impact of urban trees and forests on water resources. Although transpiration is the largest water flux leaving terrestrial ecosystems, little is known regarding whole tree transpiration in urban environments. In this study, we quantified urban tree transpiration at various temporal scales and examined...

The Use of Photographs to Portray Urban Ecosystems in Six Introductory Environmental Science Textbooks

ERIC Educational Resources Information Center

Sullivan, John P.

2008-01-01

This study examined how photographs in six introductory environmental science texts portrayed the urban environments in which most U.S. students lived. All photographs from all texts were coded to determine whether they depicted urban areas. The urban photographs were then coded to determine what they communicated about the urban environment. The…

Urban-Rural Disparities in Injury Mortality in China, 2006

ERIC Educational Resources Information Center

Hu, Guoqing; Baker, Susan P.; Baker, Timothy D.

2010-01-01

Context: Urban-rural disparity is an important issue for injury control in China. Details of the urban-rural disparities in fatal injuries have not been analyzed. Purpose: To target key injury causes that most contribute to the urban-rural disparity, we decomposed total urban-rural differences in 2006 injury mortality by gender, age, and cause.…

40 CFR 63.775 - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... source is located in an urban cluster with 10,000 people or more; the distance in miles to the nearest urbanized area boundary if the source is not located in an urban cluster with 10,000 people or more; and the names of the nearest urban cluster with 10,000 people or more and nearest urbanized area. (ii...

(Re)Constituting Teacher Identity for Inclusion in Urban Schools: A Process of Reification and Resistance

ERIC Educational Resources Information Center

Siuty, Molly Elizabeth

2017-01-01

Urban education systems serve nearly 16 million students and employ almost one million teachers in the United States. The preparation of teachers for urban settings must attend to the unique and complex historical and sociocultural context of urban communities. This includes disrupting dominant stereotypes, particularly of urban communities of…

Urban ecosystems and the North American carbon cycle

Treesearch

D.E. Pataki; R.J. Alig; A.S. Fung; E. Golubiewski; C.A. Kennedy; E.G. McPherson; D.J. Nowak; R.V. Pouyat; P. Romero Lankao

2006-01-01

Approximately 75-80% of the population of North America currently lives in urban areas as defined by national census bureaus, and urbanization is continuing to increase. Future trajectories of fossil fuel emissions are associated with a high degree of uncertainty; however, if the activities of urban residents and the rate of urban land conversion can be captured in...

Cooperative Efforts in Urban Literacy: Learnings from the Urban Literacy Network's Grant Projects.

ERIC Educational Resources Information Center

Williams, Martha

One of the major activities of the Urban Literacy Network (ULN) is a grants program aimed at supporting cooperative, collaborative approaches to developing resources and support systems for literacy in urban areas. Eleven grants were awarded in 1987-1988 in the following urban areas: Boston; Chicago; Denver; El Paso; Houston; Nashville; Oklahoma…

Accessing the Food Systems in Urban and Rural Minnesotan Communities

ERIC Educational Resources Information Center

Smith, Chery; Miller, Hannah

2011-01-01

Objective: Explore how urban and rural Minnesotans access the food system and to investigate whether community infrastructure supports a healthful food system. Design: Eight (4 urban and 4 rural) focus groups were conducted. Setting and Participants: Eight counties with urban influence codes of 1, 2, 4, 5, 8, and 10. Fifty-nine (urban, n = 27;…

A framework for adapting urban forests to climate change

Treesearch

Leslie Brandt; Abigail Derby Lewis; Robert Fahey; Lydia Scott; Lindsay Darling; Chris Swanston

2016-01-01

Planting urban trees and expanding urban forest canopy cover are often considered key strategies for reducing climate change impacts in urban areas. However, urban trees and forests can also be vulnerable to climate change through shifts in tree habitat suitability, changes in pests and diseases, and changes in extreme weather events. We developed a three-step...

A multi-scale method of mapping urban influence

Treesearch

Timothy G. Wade; James D. Wickham; Nicola Zacarelli; Kurt H. Riitters

2009-01-01

Urban development can impact environmental quality and ecosystem services well beyond urban extent. Many methods to map urban areas have been developed and used in the past, but most have simply tried to map existing extent of urban development, and all have been single-scale techniques. The method presented here uses a clustering approach to look beyond the extant...

The Educational Strategies of Citizens' Identification and Recognition for Sustainable Urban Development in Taipei

ERIC Educational Resources Information Center

Kuo, Fan-Sheng; Perng, Yeng-Horng

2016-01-01

Creating an attractive cityscape has become one of the most promising actions to improve urban functionality and increase urban competitiveness. However, the resistances from the local inhabitants are always against the urban development. Taipei City, a metropolis in Taiwan, is now composed of complex urban systems chaotically enclosed by existing…

UrbanCrowns: an assessment and monitoring tool for urban trees

Treesearch

Matthew F. Winn; Philip A. Araman; Sang-Mook Lee

2011-01-01

UrbanCrowns is a Windows®-based computer program used to assess the crown characteristics of urban trees. The software analyzes side-view digital photographs of trees to compute several crown metrics, including crown height, crown diameter, live crown ratio, crown volume, crown density, and crown transparency. Potential uses of the UrbanCrowns program include...

The Balancing Act: The Personal and Professional Challenges of Urban Teachers

ERIC Educational Resources Information Center

Durham-Barnes, Joanna

2011-01-01

While many urban teachers flee urban schools after a few years of teaching, many spend their careers in teaching in the urban environment. A series of biographical interviews was conducted with four "career" urban teachers; throughout the data collection and analyses and despite their decade or more in the field, the interactions between the…

Integrated city as a model for a new wave urban tourism

NASA Astrophysics Data System (ADS)

Ariani, V.

2018-03-01

Cities are a major player for an urban tourism destination. Massive tourism movement for urban tourism gains competitiveness to the city with similar characteristic. The new framework model for new wave urban tourism is crucial to give more experience to the tourist and valuing for the city itself. The integrated city is the answer for creating a new model for an urban tourism destination. The purpose of this preliminary research is to define integrated city framework for urban tourism development. It provides a rationale for tourism planner pursuing an innovative approach, competitive advantages, and general urban tourism destination model. The methodology applies to this research includes desk survey, literature review and focus group discussion. A conceptual framework is proposed, discussed and exemplified. The framework model adopts a place-based approach to tourism destination and suggests an integrated city model for urban tourism development. This model is a tool for strategy making in re-invention integrated city as an urban tourism destination.

The Influence of Roof Material on Diurnal Urban Canyon Breathing

NASA Astrophysics Data System (ADS)

Abuhegazy, Mohamed; Yaghoobian, Neda

2017-11-01

Improvements in building energy use, air quality in urban canyons and in general urban microclimates require understanding the complex interaction between urban morphology, materials, climate, and inflow conditions. Review of the literature indicates that despite a long history of valuable urban microclimate studies, more comprehensive approaches are needed to address energy, and heat and flow transport in urban areas. In this study, a more comprehensive simulation of the diurnally varying street canyon flow and associated heat transport is numerically investigated, using Large-eddy Simulation (LES). We use computational modeling to examine the impact of diurnal variation of the heat fluxes from urban surfaces on the air flow and temperature distribution in street canyons with a focus on the role of roof materials and their temperature footprints. A detailed building energy model with a three-dimensional raster-type geometry provides urban surface heat fluxes as thermal boundary conditions for the LES to determine the key aero-thermodynamic factors that affect urban street ventilation.

Impacts of urbanization on carbon balance in terrestrial ecosystems of the Southern United States.

PubMed

Zhang, Chi; Tian, Hanqin; Chen, Guangsheng; Chappelka, Arthur; Xu, Xiaofeng; Ren, Wei; Hui, Dafeng; Liu, Mingliang; Lu, Chaoqun; Pan, Shufen; Lockaby, Graeme

2012-05-01

Using a process-based Dynamic Land Ecosystem Model, we assessed carbon dynamics of urbanized/developed lands in the Southern United States during 1945-2007. The results indicated that approximately 1.72 (1.69-1.77) Pg (1P = 10(15)) carbon was stored in urban/developed lands, comparable to the storage of shrubland or cropland in the region. Urbanization resulted in a release of 0.21 Pg carbon to the atmosphere during 1945-2007. Pre-urbanization vegetation type and time since land conversion were two primary factors determining the extent of urbanization impacts on carbon dynamics. After a rapid decline of carbon storage during land conversion, an urban ecosystem gradually accumulates carbon and may compensate for the initial carbon loss in 70-100 years. The carbon sequestration rate of urban ecosystem diminishes with time, nearly disappearing in two centuries after land conversion. This study implied that it is important to take urbanization effect into account for assessing regional carbon balance. Published by Elsevier Ltd.

Climate change accelerates growth of urban trees in metropolises worldwide.

PubMed

Pretzsch, Hans; Biber, Peter; Uhl, Enno; Dahlhausen, Jens; Schütze, Gerhard; Perkins, Diana; Rötzer, Thomas; Caldentey, Juan; Koike, Takayoshi; Con, Tran van; Chavanne, Aurélia; Toit, Ben du; Foster, Keith; Lefer, Barry

2017-11-13

Despite the importance of urban trees, their growth reaction to climate change and to the urban heat island effect has not yet been investigated with an international scope. While we are well informed about forest growth under recent conditions, it is unclear if this knowledge can be simply transferred to urban environments. Based on tree ring analyses in ten metropolises worldwide, we show that, in general, urban trees have undergone accelerated growth since the 1960s. In addition, urban trees tend to grow more quickly than their counterparts in the rural surroundings. However, our analysis shows that climate change seems to enhance the growth of rural trees more than that of urban trees. The benefits of growing in an urban environment seem to outweigh known negative effects, however, accelerated growth may also mean more rapid ageing and shortened lifetime. Thus, city planners should adapt to the changed dynamics in order to secure the ecosystem services provided by urban trees.

A climate responsive urban design tool: a platform to improve energy efficiency in a dry hot climate

NASA Astrophysics Data System (ADS)

El Dallal, Norhan; Visser, Florentine

2017-09-01

In the Middle East and North Africa (MENA) region, new urban developments should address the climatic conditions to improve outdoor comfort and to reduce the energy consumption of buildings. This article describes a design tool that supports climate responsive design for a dry hot climate. The approach takes the climate as an initiator for the conceptual urban form with a more energy-efficient urban morphology. The methodology relates the different passive strategies suitable for major climate conditions in MENA region (dry-hot) to design parameters that create the urban form. This parametric design approach is the basis for a tool that generates conceptual climate responsive urban forms so as to assist the urban designer early in the design process. Various conceptual scenarios, generated by a computational model, are the results of the proposed platform. A practical application of the approach is conducted on a New Urban Community in Aswan (Egypt), showing the economic feasibility of the resulting urban form and morphology, and the proposed tool.

Groundwater sustainability and urban development - a major challenge for the 21st century

NASA Astrophysics Data System (ADS)

Foster, Stephen

2016-04-01

Groundwater is a critical, but often under appreciated, resource for urban water supply, a serious and costly hazard to urban infrastructure, and the 'invisible link' between various facets of the urbanisation process. An overview is presented of the benefits of urban groundwater use, together with some insidious and persistent problems that groundwater can present (especially those related to groundwater pollution from inadequate sanitation) for urban development. Spontaneous piecemeal approaches invariably mean that 'one person's solution becomes another person's problem' - and there is a strong argument for groundwater considerations to be part of a more holistic approach to urban infrastructure planning and management. However this is not a simple task because of the widespread vacuum of institutional responsibility and accountability for groundwater in urban areas. The current state of urban groundwater management will be reviewed, and pragmatic solutions to strengthening various facets of urban groundwater governance and management presented, using examples from Latin America and South Asia.

The Global Pattern of Urbanization and Economic Growth: Evidence from the Last Three Decades

PubMed Central

Chen, Mingxing; Zhang, Hua; Liu, Weidong; Zhang, Wenzhong

2014-01-01

The relationship between urbanization and economic growth has been perplexing. In this paper, we identify the pattern of global change and the correlation of urbanization and economic growth, using cross-sectional, panel estimation and geographic information systems (GIS) methods. The analysis has been carried out on a global geographical scale, while the timescale of the study spans the last 30 years. The data shows that urbanization levels have changed substantially during these three decades. Empirical findings from cross-sectional data and panel data support the general notion of close links between urbanization levels and GDP per capita. However, we also present significant evidence that there is no correlation between urbanization speed and economic growth rate at the global level. Hence, we conclude that a given country cannot obtain the expected economic benefits from accelerated urbanization, especially if it takes the form of government-led urbanization. In addition, only when all facets are taken into consideration can we fully assess the urbanization process. PMID:25099392

The global pattern of urbanization and economic growth: evidence from the last three decades.

PubMed

Chen, Mingxing; Zhang, Hua; Liu, Weidong; Zhang, Wenzhong

2014-01-01

The relationship between urbanization and economic growth has been perplexing. In this paper, we identify the pattern of global change and the correlation of urbanization and economic growth, using cross-sectional, panel estimation and geographic information systems (GIS) methods. The analysis has been carried out on a global geographical scale, while the timescale of the study spans the last 30 years. The data shows that urbanization levels have changed substantially during these three decades. Empirical findings from cross-sectional data and panel data support the general notion of close links between urbanization levels and GDP per capita. However, we also present significant evidence that there is no correlation between urbanization speed and economic growth rate at the global level. Hence, we conclude that a given country cannot obtain the expected economic benefits from accelerated urbanization, especially if it takes the form of government-led urbanization. In addition, only when all facets are taken into consideration can we fully assess the urbanization process.

The Power of Micro Urban Structures, Theory of EEPGC - the Micro Urban Energy Distribution Model as a Planning Tool for Sustainable City Development

NASA Astrophysics Data System (ADS)

Tkáč, Štefan

2015-11-01

To achieve the smart growth and equitable development in the region, urban planners should consider also lateral energies represented by the energy urban models like further proposed EEPGC focused on energy distribution via connections among micro-urban structures, their onsite renewable resources and the perception of micro-urban structures as decentralized energy carriers based on pre industrialized era. These structures are still variously bound when part of greater patterns. After the industrial revolution the main traded goods became energy in its various forms. The EEPGC is focused on sustainable energy transportation distances between the villages and the city, described by the virtual "energy circles". This more human scale urbanization, boost the economy in micro-urban areas, rising along with clean energy available in situ that surely gives a different perspective to human quality of life in contrast to overcrowded multicultural mega-urban structures facing generations of problems and struggling to survive as a whole.

Neighbourhood Environmental Attributes Associated with Walking in South Australian Adults: Differences between Urban and Rural Areas

PubMed Central

Coffee, Neil T.; Nolan, Rebecca; Dollman, James; Sugiyama, Takemi

2017-01-01

Although the health benefits of walking are well established, participation is lower in rural areas compared to urban areas. Most studies on walkability and walking have been conducted in urban areas, thus little is known about the relevance of walkability to rural areas. A computer-assisted telephone survey of 2402 adults (aged ≥18 years) was conducted to determine walking behaviour and perceptions of neighbourhood walkability. Data were stratified by urban (n = 1738) and rural (n = 664). A greater proportion of respondents reported no walking in rural (25.8%) compared to urban areas (18.5%). Compared to urban areas, rural areas had lower walkability scores and urban residents reported higher frequency of walking. The association of perceived walkability with walking was significant only in urban areas. These results suggest that environmental factors associated with walking in urban areas may not be relevant in rural areas. Appropriate walkability measures specific to rural areas should be further researched. PMID:28846597

Urbanization and stream ecology: Diverse mechanisms of change

USGS Publications Warehouse

Roy, Allison; Capps, Krista A.; El-Sabaawi, Rana W.; Jones, Krista L.; Parr, Thomas B.; Ramirez, Alonso; Smith, Robert F.; Walsh, Christopher J.; Wenger, Seth J.

2016-01-01

The field of urban stream ecology has evolved rapidly in the last 3 decades, and it now includes natural scientists from numerous disciplines working with social scientists, landscape planners and designers, and land and water managers to address complex, socioecological problems that have manifested in urban landscapes. Over the last decade, stream ecologists have met 3 times at the Symposium on Urbanization and Stream Ecology (SUSE) to discuss current research, identify knowledge gaps, and promote future research collaborations. The papers in this special series on urbanization and stream ecology include both primary research studies and conceptual synthesis papers spurred from discussions at SUSE in May 2014. The themes of the meeting are reflected in the papers in this series emphasizing global differences in mechanisms and responses of stream ecosystems to urbanization and management solutions in diverse urban streams. Our hope is that this series will encourage continued interdisciplinary and collaborative research to increase the global understanding of urban stream ecology toward stream protection and restoration in urban landscapes.

Preliminary Analysis of the efficacy of Artificial neural Network (ANN) and Cellular Automaton (CA) based Land Use Models in Urban Land-Use Planning

NASA Astrophysics Data System (ADS)

Harun, R.

2013-05-01

This research provides an opportunity of collaboration between urban planners and modellers by providing a clear theoretical foundations on the two most widely used urban land use models, and assessing the effectiveness of applying the models in urban planning context. Understanding urban land cover change is an essential element for sustainable urban development as it affects ecological functioning in urban ecosystem. Rapid urbanization due to growing inclination of people to settle in urban areas has increased the complexities in predicting that at what shape and size cities will grow. The dynamic changes in the spatial pattern of urban landscapes has exposed the policy makers and environmental scientists to great challenge. But geographic science has grown in symmetry to the advancements in computer science. Models and tools are developed to support urban planning by analyzing the causes and consequences of land use changes and project the future. Of all the different types of land use models available in recent days, it has been found by researchers that the most frequently used models are Cellular Automaton (CA) and Artificial Neural Networks (ANN) models. But studies have demonstrated that the existing land use models have not been able to meet the needs of planners and policy makers. There are two primary causes identified behind this prologue. First, there is inadequate understanding of the fundamental theories and application of the models in urban planning context i.e., there is a gap in communication between modellers and urban planners. Second, the existing models exclude many key drivers in the process of simplification of the complex urban system that guide urban spatial pattern. Thus the models end up being effective in assessing the impacts of certain land use policies, but cannot contribute in new policy formulation. This paper is an attempt to increase the knowledge base of planners on the most frequently used land use model and also assess the relative effectiveness of the two models, ANN and CA, in urban planning. The questions that are addressed in this research are: a) What makes ANN models different from CA models?; b) Which model has higher accuracy in predicting future urban land use change?; and c) Are the models effective enough in guiding urban land use policies and strategies? The models that are used for this research are Multilayer Perceptron (MLP) and CA model, available in IDRISI Taiga. Since, the objective is to perform a comparative analysis and draw general inferences irrespective of specific urban policies, the availability of data was given more emphasis over the selection of particular location. Urban area in Massachusetts was chosen to conduct the study due to data availability. Extensive literature review was performed to understand the functionality of the two models. The models were applied to predict future changes and the accuracy assessment was performed using standard matrix. Inferences were drawn about the applicability of the models in urban planning context along with recommendations. This research will not only develop understanding of land use models among urban planners, but also will create an environment of coupled research between planners and modellers.

Urban Land Use Change Effects on Below and Aboveground Carbon Stocks—a Global Perspective and Future Research Needs

NASA Astrophysics Data System (ADS)

Pouyat, R. V.; Chen, Y.; Yesilonis, I.; Day, S.

2014-12-01

Land use change (LUC) has a significant impact on both above- and below-ground carbon (C) stocks; however, little is known about the net effects of urban LUC on the C cycle and climate system. Moreover, as climate change becomes an increasingly pressing concern, there is growing evidence that urban policy and management decisions can have significant regional impacts on C dynamics. Soil organic carbon (SOC) varies significantly across ecoregions at global and continental scales due to differential sensitivity of primary production, substrate quality, and organic matter decay to changes in temperature and soil moisture. These factors are highly modified by urban LUC due to vegetation removal, soil relocation and disruption, pollution, urban heat island effects, and increased atmospheric CO2 concentrations. As a result, on a global scale urban LUC differentially affects the C cycle from ecoregion to ecoregion. For urban ecosystems, the data collected thus far suggests urbanization can lead to both an increase and decrease in soil C pools and fluxes, depending on the native ecosystem being impacted by urban development. For example, in drier climates, urban landscapes accumulate higher C densities than the native ecosystems they replaced. Results suggest also that soil C storage in urban ecosystems is highly variable with very high (> 20.0) and low (< 2.0) C densities (kg m-2 to a 1 m depth) present in the landscape at any one time. Moreover, similar to non-urban soils, total SOC densities are consistently 2-fold greater than aboveground stocks. For those soils with low SOC densities, there is potential to increase C sequestration through management, but specific urban related management practices need to be evaluated. In addition, urban LUC is a human-driven process and thus can be modified or adjusted to reduce its impacts on the C cycle. For example, policies that influence development patterns, population density, management practices, and other human factors can greatly ameliorate the impact of urban LUC on the C cycle. However, even with the recent and rapid expansion of newly acquired data, the net effects of urban LUC on C stocks and fluxes have not been comprehensively addressed. Furthermore, how sensitive these changes are to urban planning, policy decisions, and site management needs to be explored.

Modification of Heat-Related Mortality in an Elderly Urban Population by Vegetation (Urban Green) and Proximity to Water (Urban Blue): Evidence from Lisbon, Portugal.

PubMed

Burkart, Katrin; Meier, Fred; Schneider, Alexandra; Breitner, Susanne; Canário, Paulo; Alcoforado, Maria João; Scherer, Dieter; Endlicher, Wilfried

2016-07-01

Urban populations are highly vulnerable to the adverse effects of heat, with heat-related mortality showing intra-urban variations that are likely due to differences in urban characteristics and socioeconomic status. We investigated the influence of urban green and urban blue, that is, urban vegetation and water bodies, on heat-related excess mortality in the elderly > 65 years old in Lisbon, Portugal, between 1998 and 2008. We used remotely sensed data and geographic information to determine the amount of urban vegetation and the distance to bodies of water (the Atlantic Ocean and the Tagus Estuary). Poisson generalized additive models were fitted, allowing for the interaction between equivalent temperature [universal thermal climate index (UTCI)] and quartiles of urban greenness [classified using the Normalized Difference Vegetation Index (NDVI)] and proximity to water (≤ 4 km vs. > 4 km), while adjusting for potential confounders. The association between mortality and a 1°C increase in UTCI above the 99th percentile (24.8°C) was stronger for areas in the lowest NDVI quartile (14.7% higher; 95% CI: 1.9, 17.5%) than for areas in the highest quartile (3.0%; 95% CI: 2.0, 4.0%). In areas > 4 km from water, a 1°C increase in UTCI above the 99th percentile was associated with a 7.1% increase in mortality (95% CI: 6.2, 8.1%), whereas in areas ≤ 4 km from water, the estimated increase in mortality was only 2.1% (95% CI: 1.2, 3.0%). Urban green and blue appeared to have a mitigating effect on heat-related mortality in the elderly population in Lisbon. Increasing the amount of vegetation may be a good strategy to counteract the adverse effects of heat in urban areas. Our findings also suggest potential benefits of urban blue that may be present several kilometers from a body of water. Burkart K, Meier F, Schneider A, Breitner S, Canário P, Alcoforado MJ, Scherer D, Endlicher W. 2016. Modification of heat-related mortality in an elderly urban population by vegetation (urban green) and proximity to water (urban blue): evidence from Lisbon, Portugal. Environ Health Perspect 124:927-934; http://dx.doi.org/10.1289/ehp.1409529.

Child health inequities in developing countries: differences across urban and rural areas

PubMed Central

Fotso, Jean-Christophe

2006-01-01

Objectives To document and compare the magnitude of inequities in child malnutrition across urban and rural areas, and to investigate the extent to which within-urban disparities in child malnutrition are accounted for by the characteristics of communities, households and individuals. Methods The most recent data sets available from the Demographic and Health Surveys (DHS) of 15 countries in sub-Saharan Africa (SSA) are used. The selection criteria were set to ensure that the number of countries, their geographical spread across Western/Central and Eastern/Southern Africa, and their socioeconomic diversities, constitute a good yardstick for the region and allow us to draw some generalizations. A household wealth index is constructed in each country and area (urban, rural), and the odds ratio between its uppermost and lowermost category, derived from multilevel logistic models, is used as a measure of socioeconomic inequalities. Control variables include mother's and father's education, community socioeconomic status (SES) designed to represent the broad socio-economic ecology of the neighborhoods in which families live, and relevant mother- and child-level covariates. Results Across countries in SSA, though socioeconomic inequalities in stunting do exist in both urban and rural areas, they are significantly larger in urban areas. Intra-urban differences in child malnutrition are larger than overall urban-rural differentials in child malnutrition, and there seem to be no visible relationships between within-urban inequities in child health on the one hand, and urban population growth, urban malnutrition, or overall rural-urban differentials in malnutrition, on the other. Finally, maternal and father's education, community SES and other measurable covariates at the mother and child levels only explain a slight part of the within-urban differences in child malnutrition. Conclusion The urban advantage in health masks enormous disparities between the poor and the non-poor in urban areas of SSA. Specific policies geared at preferentially improving the health and nutrition of the urban poor should be implemented, so that while targeting the best attainable average level of health, reducing gaps between population groups is also on target. To successfully monitor the gaps between urban poor and non-poor, existing data collection programs such as the DHS and other nationally representative surveys should be re-designed to capture the changing patterns of the spatial distribution of population. PMID:16831231

Child health inequities in developing countries: differences across urban and rural areas.

PubMed

Fotso, Jean-Christophe

2006-07-11

To document and compare the magnitude of inequities in child malnutrition across urban and rural areas, and to investigate the extent to which within-urban disparities in child malnutrition are accounted for by the characteristics of communities, households and individuals. The most recent data sets available from the Demographic and Health Surveys (DHS) of 15 countries in sub-Saharan Africa (SSA) are used. The selection criteria were set to ensure that the number of countries, their geographical spread across Western/Central and Eastern/Southern Africa, and their socioeconomic diversities, constitute a good yardstick for the region and allow us to draw some generalizations. A household wealth index is constructed in each country and area (urban, rural), and the odds ratio between its uppermost and lowermost category, derived from multilevel logistic models, is used as a measure of socioeconomic inequalities. Control variables include mother's and father's education, community socioeconomic status (SES) designed to represent the broad socio-economic ecology of the neighborhoods in which families live, and relevant mother- and child-level covariates. Across countries in SSA, though socioeconomic inequalities in stunting do exist in both urban and rural areas, they are significantly larger in urban areas. Intra-urban differences in child malnutrition are larger than overall urban-rural differentials in child malnutrition, and there seem to be no visible relationships between within-urban inequities in child health on the one hand, and urban population growth, urban malnutrition, or overall rural-urban differentials in malnutrition, on the other. Finally, maternal and father's education, community SES and other measurable covariates at the mother and child levels only explain a slight part of the within-urban differences in child malnutrition. The urban advantage in health masks enormous disparities between the poor and the non-poor in urban areas of SSA. Specific policies geared at preferentially improving the health and nutrition of the urban poor should be implemented, so that while targeting the best attainable average level of health, reducing gaps between population groups is also on target. To successfully monitor the gaps between urban poor and non-poor, existing data collection programs such as the DHS and other nationally representative surveys should be re-designed to capture the changing patterns of the spatial distribution of population.

Sizing and serving Texas urban gaps.

DOT National Transportation Integrated Search

2011-09-01

Federal and state funding is largely distributed based upon federally defined geographic areasurbanized : areas or rural areas (non-urbanized areas). For urban transit districts, the funding is based upon : characteristics of the entire urbanized ...

Neighborhood Variation of Sustainable Urban Morphological Characteristics.

PubMed

Lai, Poh-Chin; Chen, Si; Low, Chien-Tat; Cerin, Ester; Stimson, Robert; Wong, Pui Yun Paulina

2018-03-07

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities.

Relationship between road traffic noisescape and urban form in Hong Kong.

PubMed

Lam, Kin-Che; Ma, Weichun; Chan, Pak Kin; Hui, Wing Chi; Chung, King Lam; Chung, Yi-tak Teresa; Wong, Chun Yin; Lin, Hui

2013-12-01

This paper reports on a study which explored the possible relationship between road traffic noisescape and urban form in Hong Kong. A total of 212 residential complexes from 11 contrasting urban forms were sampled, and their noise levels assessed both at dwelling and neighbourhood scales by noise mapping. Its findings indicate that residential complexes with different urban forms have significantly different noisescape attributes. There is a strong correlation between the noise characteristics and morphological indicators at the dwelling scale. A less obstreperous noisescape is associated with urban forms with lower road and building densities, and with building arrangements which provide self-noise screening. These findings suggest that urban form is an influential determinant of the noisescape in the urban environment, and they point to the need to rethink the conventional approach to managing the urban acoustic environment.

Neighborhood Variation of Sustainable Urban Morphological Characteristics

PubMed Central

Chen, Si; Stimson, Robert

2018-01-01

Compact cities and their urban forms have implications on sustainable city development because of high density urban settlement, increased accessibility, and a balanced land use mix. This paper uses quantitative means of understanding urban morphological characteristics with reference to the differing qualities of the urban form (i.e., street patterns, building volumes, land uses and greenery). The results, based on 89 neighborhood communities of Hong Kong, show varying degrees of regional differences in the urban built form supported by numerical statistics and graphical illustrations. This paper offers empirical evidence on some morphological characteristics that can be estimated objectively using modern geospatial technologies and applied universally to inform urban planning. However, more studies linking these quantifiable measures of the physical form with sustainable urban living are needed to account for human comfort in the totality of environmental, social, and economic responsibilities. PMID:29518956

Impact of the urban heat island on residents’ energy consumption: a case study of Qingdao

NASA Astrophysics Data System (ADS)

Ding, Feng; Pang, Huaji; Guo, Wenhui

2018-02-01

This paper examines impact of urban heat island on residents’ energy consumption through comparative analyses of monthly air temperature data observed in Qingdao, Laoshan and Huangdao weather stations. The results show effect of urban heat island is close related with urbanization speed. Recently, effects of urban heat island of Laoshan and Huangdao exceed that of Qingdao, consistent with rapid urbanization in Laoshan and Huangdao. Enhanced effect of urban heat island induces surface air temperature to rise up, further increase electricity energy consumption for air conditioning use in summer and reduce coal consumption for residents heating in winter. Comparing change of residents’ energy consumption in summer and winter, increments in summer are less than reduction in winter. This implicates effect of urban heat island is more obvious in winter than in summer.

Urban health and ecology: the promise of an avian biomonitoring tool

PubMed Central

Pollack, Lea; Ondrasek, Naomi R.

2017-01-01

Abstract Urban-dwelling birds have the potential to serve as powerful biomonitors that reveal the impact of environmental change due to urbanization. Specifically, urban bird populations can be used to survey cities for factors that may pose both public and wildlife health concerns. Here, we review evidence supporting the use of avian biomonitors to identify threats associated with urbanization, including bioaccumulation of toxicants and the dysregulation of behavior and physiology by related stressors. In addition, we consider the use of birds to examine how factors in the urban environment can impact immunity against communicable pathogens. By studying the behavior, physiology, and ecology of urban bird populations, we can elucidate not only how avian populations are responding to environmental change, but also how unintended consequences of urbanization affect the well-being of human and non-human inhabitants. PMID:29491978

Urban health and ecology: the promise of an avian biomonitoring tool.

PubMed

Pollack, Lea; Ondrasek, Naomi R; Calisi, Rebecca

2017-04-01

Urban-dwelling birds have the potential to serve as powerful biomonitors that reveal the impact of environmental change due to urbanization. Specifically, urban bird populations can be used to survey cities for factors that may pose both public and wildlife health concerns. Here, we review evidence supporting the use of avian biomonitors to identify threats associated with urbanization, including bioaccumulation of toxicants and the dysregulation of behavior and physiology by related stressors. In addition, we consider the use of birds to examine how factors in the urban environment can impact immunity against communicable pathogens. By studying the behavior, physiology, and ecology of urban bird populations, we can elucidate not only how avian populations are responding to environmental change, but also how unintended consequences of urbanization affect the well-being of human and non-human inhabitants.

On the Nexus of the Spatial Dynamics of Global Urbanization and the Age of the City

PubMed Central

Scheuer, Sebastian; Haase, Dagmar; Volk, Martin

2016-01-01

A number of concepts exist regarding how urbanization can be described as a process. Understanding this process that affects billions of people and its future development in a spatial manner is imperative to address related issues such as human quality of life. In the focus of spatially explicit studies on urbanization is typically a city, a particular urban region, an agglomeration. However, gaps remain in spatially explicit global models. This paper addresses that issue by examining the spatial dynamics of urban areas over time, for a full coverage of the world. The presented model identifies past, present and potential future hotspots of urbanization as a function of an urban area's spatial variation and age, whose relation could be depicted both as a proxy and as a path of urban development. PMID:27490199

On the Nexus of the Spatial Dynamics of Global Urbanization and the Age of the City.

PubMed

Scheuer, Sebastian; Haase, Dagmar; Volk, Martin

2016-01-01

A number of concepts exist regarding how urbanization can be described as a process. Understanding this process that affects billions of people and its future development in a spatial manner is imperative to address related issues such as human quality of life. In the focus of spatially explicit studies on urbanization is typically a city, a particular urban region, an agglomeration. However, gaps remain in spatially explicit global models. This paper addresses that issue by examining the spatial dynamics of urban areas over time, for a full coverage of the world. The presented model identifies past, present and potential future hotspots of urbanization as a function of an urban area's spatial variation and age, whose relation could be depicted both as a proxy and as a path of urban development.

Status of NASA Satellite, Field Observations, and Numerical Modeling Addressing the Impact of Urbanization on Short and Long Term Precipitation Variability

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Manyin, Michael; Burian, Steve; Garza, Carlos

2004-01-01

Howard (1833a) made the first documented observation of a temperature difference between an urban area and its rural environment. Manley (1958) termed this contrast the "urban heat island (UHI)". The UHI has now become a widely acknowledged, observed, and researched phenomenon because of its broad implications. It is estimated that by the year 2025, 60% of the world's population will live in cities (UNFP, 1999). In the United States, the current urban growth rate is approximately 12.5%, with 80% currently living in urban areas. As cities continue to grow, urban sprawl creates unique problems related to land use, transportation, agriculture, housing, pollution, and development for policymakers. Urban expansion and its associated urban heat islands also have measurable impacts on weather and climate processes.

Association of West Nile virus illness and urban landscapes in Chicago and Detroit.

PubMed

Ruiz, Marilyn O; Walker, Edward D; Foster, Erik S; Haramis, Linn D; Kitron, Uriel D

2007-03-12

West Nile virus infection in humans in urban areas of the Midwestern United States has exhibited strong spatial clustering during epidemic years. We derived urban landscape classes from the physical and socio-economic factors hypothesized to be associated with West Nile Virus (WNV) transmission and compared those to human cases of illness in 2002 in Chicago and Detroit. The objectives were to improve understanding of human exposure to virus-infected mosquitoes in the urban context, and to assess the degree to which environmental factors found to be important in Chicago were also found in Detroit. Five urban classes that partitioned the urban space were developed for each city region. The classes had many similarities in the two settings. In both regions, the WNV case rate was considerably higher in the urban class associated with the Inner Suburbs, where 1940-1960 era housing dominates, vegetation cover is moderate, and population density is moderate. The land cover mapping approach played an important role in the successful and consistent classification of the urban areas. The analysis demonstrates how urban form and past land use decisions can influence transmission of a vector-borne virus. In addition, the results are helpful to develop hypotheses regarding urban landscape features and WNV transmission, they provide a structured method to stratify the urban areas to locate representative field study sites specifically for WNV, and this analysis contributes to the question of how the urban environment affects human health.

City-Dwellers and Country Folks: Lack of Population Differentiation Along an Urban-Rural Gradient in the Mosquito Culex pipiens (Diptera: Culicidae).

PubMed

Honnen, Ann-Christin; Monaghan, Michael T; Sharakhov, Igor

2017-09-01

Mosquitoes (Diptera, Culicidae) occur in natural, urban, and peri-urban areas throughout the globe. Although the characteristics of urban and peri-urban habitats differ from those of natural habitats in many ways (e.g., fragmentation, pollution, noise, and light), few studies have examined the population connectivity of mosquitoes in urban areas. To obtain an overview of the species composition, we sampled mosquitoes from 23 sites in and around the city of Berlin, Germany. Of 23 species, five occurred in urban, 10 in peri-urban, and 20 in rural areas. Culex pipiens Linnaeus (Diptera: Culicidae) was the most common species collected (75% of all individuals) and occurred in all habitats. Hence this species was selected to be analysed at 10 microsatellite markers. There was no significant differentiation (FST = 0.016, P = 0.9) or isolation by distance (P = 0.06) among Cx. pipiens populations along an urban-rural gradient. The only significant differences detected were between Cx. pipiens and a laboratory population of Cx. pipiens f. molestus (pairwise FST = 0.114-0.148, P ≤ 0.001 in all comparisons), suggesting that the markers chosen were suitable for the identification of population differentiation. Our results indicate that Cx. pipiens gene flow is widespread within and among urban, peri-urban, and rural areas and that urban habitat does not necessarily impede or enhance gene flow among these populations. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Satellite Imagery Data: Dynamic Systems Model for sustainable urban forest in area of Halim Perdana Kusuma, East Jakarta

NASA Astrophysics Data System (ADS)

Sundara, D. M.; Hartono, D. M.; Suganda, E.; Haeruman, JS H.

2018-05-01

East Jakarta icon as a buffer and the lungs of the city is still a big dream of Jakarta. It is a classic problem that there is a struggle for land between current economic interests and sustainable environmental interests for the future. This paper discusses the development of urban forest area of Halim Perdana Kusuma, East Jakarta. The forest area according to regulations of existing city local governments is not enough to support sustainable urban development indicators. Therefore, it requires an extensive mapping of urban forest potential development accurately by utilizing satellite imaging technology. Landsat-TM satellite imagery data can provide a full picture of the potential land width for urban forest area development. The results of this satellite image will then be made into a model of urban forest as one of the indicators of sustainable urban development. This research aims to support sustainable urban development through environmental balance in the form of a green neighborhood revitalization and development of urban forests and to create socio-economic balance. This paper uses a dynamic system model to simulate the conditions of the region against the intervention performed in the potential area for development of urban forests which are derived from urban spatial analysis based on satellite image data, using GIS program as a tool. The result is a model of urban forest area which is integrated with a social and economic function to encourage the development of sustainable cities.

Are winds in cities always slower than in the countryside? Modelling the Urban Wind Island Effect

NASA Astrophysics Data System (ADS)

Droste, Arjan; Steeneveld, Gert-Jan

2017-04-01

Though the Urban Heat Island has been extensively studied, relatively little has been documented about differences in wind between the city as a whole and the countryside. Urban winds are difficult to capture in both observations and modelling, due to the complex urban canyon and neighbourhood geometry. This study uses a straightforward mixed-layer model (Tennekes & Driedonks, 1981) to investigate the contrast between the diurnal cycle of wind in the urban and the rural environment. The model contains one urban and one rural column, to identify differences in wind patterns between city and countryside under equal geostrophic forcing. The model has been evaluated against rural observations from the 213 m. Cabauw tower (the Netherlands), and the urban observations from the BUBBLE campaign (Basel, Rotach et al., 2005). The influence of the urban fabric on the wind is investigated by varying the surface underneath the column model using the 10 urban Local Climate Zones, thereby altering building height, fraction of impervious surface, and initial boundary-layer depth. First results show that for high initial urban boundary-layer depths compared to the rural boundary-layer depth, the urban column can be much windier than its rural counterpart: i.e. the urban Wind Island Effect. The effect appears to be most prominent in the morning and the late afternoon (up to 1 m/s), for Local Climate Zones with lower buildings (3 or 7). BUBBLE observations confirm the timing of the Wind Island Effect, though with weaker magnitude.

Reserch on Urban Spatial Expansion Model Based on Multi-Object Gray Decision-Making and Ca: a Case Study of Pidu District, Chengdu City

NASA Astrophysics Data System (ADS)

Liu, Z.; Li, Y.

2018-04-01

This paper from the perspective of the Neighbor cellular space, Proposed a new urban space expansion model based on a new multi-objective gray decision and CA. The model solved the traditional cellular automata conversion rules is difficult to meet the needs of the inner space-time analysis of urban changes and to overcome the problem of uncertainty in the combination of urban drivers and urban cellular automata. At the same time, the study takes Pidu District as a research area and carries out urban spatial simulation prediction and analysis, and draws the following conclusions: (1) The design idea of the urban spatial expansion model proposed in this paper is that the urban driving factor and the neighborhood function are tightly coupled by the multi-objective grey decision method based on geographical conditions. The simulation results show that the simulation error of urban spatial expansion is less than 5.27 %. The Kappa coefficient is 0.84. It shows that the model can better capture the inner transformation mechanism of the city. (2) We made a simulation prediction for Pidu District of Chengdu by discussing Pidu District of Chengdu as a system instance.In this way, we analyzed the urban growth tendency of this area.presenting a contiguous increasing mode, which is called "urban intensive development". This expansion mode accorded with sustainable development theory and the ecological urbanization design theory.

Urban geometry effects on the microclimate of streets near the river

NASA Astrophysics Data System (ADS)

Park, C.; Lee, D. K.; Asawa, T.; Murakami, A.; Kim, H. G.; Jeong, W.

2016-12-01

These days, many urbans have undergone urban heat islands (UHIs) which mean urban areas have higher temperature than surrounding areas. Because of UHIs, extreme heat waves and tropical nights threaten citizen's health. For reducing UHI effects, UHIs mitigation strategies related with urban planning (cooling elements, urban geometry, and urban materials) are studied in many fields. Especially, cooling elements such as vegetation and water are important for making sustainable cities. However, while the each effects of cooling elements are known, combination effects between urban geometry and elements are not clearly defined. To determine which urban geometry is effective to decrease air temperature, we analyzed urban geometry effects on the microclimate of streets near the river. The urban streets located in commercial area near the Cheonggye River and they had different aspect ratio. For doing this, we used field measurement. Field measurement were takin in the sunny days of July and August 2016. Air temperature measurement used T-type thermometers with cylindrical tube and ventilation fan. Wind measurements used kestrel 4500 for wind speed and wind direction. We measured air temperature in the screen level and repeated three times an hour. Measurement results showed that large aspect ratio street show lower air temperature than small ones. And they received cooling effect farther than others from the river. This is because that cooling air flows well in the wide road streets. Large aspect ratio streets are effective to receive river's cooling air. These results can be used in the urban geometry planning near the river.

Agriculture and irrigation as potential drivers of urban heat island

NASA Astrophysics Data System (ADS)

Kumar, R.; Buzan, J. R.; Mishra, V.; Kumar, R.; Shindell, D. T.; Huber, M.

2017-12-01

More than half the population are urban dwellers and are most vulnerable to global environmental changes. Urban extents are more prone to intense heating as compared to the surroundings rural area. Presently about 33% of India's population lives in the urban area and is expected to rise steeply, so a better understanding of the phenomenon affecting the urban population is very much important. Urban Heat Island (UHI) is a well-known phenomenon which potentially affects energy consumption, spreading of diseases and mortality. In general, almost all (90%) of the major urban area of the country faces UHI at night time in the range (1-5 °C) while 60% of the regions face Urban Cool Island (UCI) in the range of -1 to 6 °C in day time. Our observations and simulations show that vegetation and irrigation in the surrounding non urban directly affects day time Urban Cool Island effects. This is due to the relative cooling by vegetation and irrigated lands in the vicinity of these urban regions. There is a contrasting variation in UHI/UCI intensities in different seasons and in different time of the day. Most of the urban regions face UHI effect in summers whereas this phenomenton reverses in winters. Daytime UCI is more prominent in the months of April and May due to minimum availability of moisture. We observed that apart from vegetation and irrigation, aerosol is also an important factor governing UHI phenomenon.

How do the definitions of urban and rural matter for transportation safety? Re-interpreting transportation fatalities as an outcome of regional development processes.

PubMed

McAndrews, Carolyn; Beyer, Kirsten; Guse, Clare E; Layde, Peter

2016-12-01

Urban and rural places are integrated through economic ties and population flows. Despite their integration, most studies of road safety dichotomize urban and rural places, and studies have consistently demonstrated that rural places are more dangerous for motorists than urban places. Our study investigates whether these findings are sensitive to the definition of urban and rural. We use three different definitions of urban-rural continua to quantify and compare motor vehicle occupant fatality rates per person-trip and person-mile for the state of Wisconsin. The three urban-rural continua are defined by: (1) popular impressions of urban, suburban, and rural places using a system from regional economics; (2) population density; and (3) the intensity of commute flows to core urbanized areas. In this analysis, the three definitions captured different people and places within each continuum level, highlighting rural heterogeneity. Despite this heterogeneity, the three definitions resulted in similar fatality rate gradients, suggesting a potentially latent "rural" characteristic. We then used field observations of urban-rural transects to refine the definitions. When accounting for the presence of higher-density towns and villages in rural places, we found that low-density urban places such as suburbs and exurbs have fatality rates more similar to those in rural places. These findings support the need to understand road safety within the context of regional development processes instead of urban-rural categories. Copyright © 2016 Elsevier Ltd. All rights reserved.

Trends of urban surface temperature and heat island characteristics in the Mediterranean

NASA Astrophysics Data System (ADS)

Benas, Nikolaos; Chrysoulakis, Nektarios; Cartalis, Constantinos

2017-11-01

Urban air temperature studies usually focus on the urban canopy heat island phenomenon, whereby the city center experiences higher near surface air temperatures compared to its surrounding non-urban areas. The Land Surface Temperature (LST) is used instead of urban air temperature to identify the Surface Urban Heat Island (SUHI). In this study, the nighttime LST and SUHI characteristics and trends in the seventeen largest Mediterranean cities were investigated, by analyzing satellite observations for the period 2001-2012. SUHI averages and trends were based on an innovative approach of comparing urban pixels to randomly selected non-urban pixels, which carries the potential to better standardize satellite-derived SUHI estimations. A positive trend for both LST and SUHI for the majority of the examined cities was documented. Furthermore, a 0.1 °C decade-1 increase in urban LST corresponded to an increase in SUHI by about 0.04 °C decade-1. A longitudinal differentiation was found in the urban LST trends, with higher positive values appearing in the eastern Mediterranean. Examination of urban infrastructure and development factors during the same period revealed correlations with SUHI trends, which can be used to explain differences among cities. However, the majority of the cities examined show considerably increased trends in terms of the enhancement of SUHI. These findings are considered important so as to promote sustainable urbanization, as well as to support the development of heat island adaptation and mitigation plans in the Mediterranean.

Gender, migration and urban development in Costa Rica: the case of Guanacaste.

PubMed

Chant, S

1991-01-01

Factors fueling urbanization in Guanacaste province, Costa Rica are explored and how the pattern of urban growth reflects gender divisions of labor is considered. Urbanization in Latin America has been due largely to the expansion of economic activities in urban centers, but in Guanacaste, rural employment persists among the poor. Towns in this peripheral province have witnessed no major expansion in urban-based employment opportunities. On the basis of an in-depth survey of urban dwellers in the province's 3 leading towns (Liberia, Canas, and Santa Cruz), an attempt is made to explain Guanacaste's urbanization. The 1st section discusses the migration, urbanization, and economic development in Costa Rica, as well as Guanacaste. The 2nd section provides the findings of the survey of 350 low-income, urban households in Guanacaste, focusing on the households' reported reasons for moving. Section 3 examines household survival strategies in the areas surveyed, paying close attention to gender and age selectivity of short-term out-migration to external labor markets. Section 4 interprets the apparent connection between gender-differentiated labor migration and the dominance of reproductive factors in household decisions to move to urban centers. Section 5 considers the implications of the migration patterns on women, while section 6 discusses the wider implications of the study. The study reveals that in Guanacaste, urbanization is more strongly linked to the reproductive (e.g., housing and welfare) needs of household survival than to productive (employment and income) needs.

The use of GIS for monitoring and predicting urban growth in east and west St Paul, Winnipeg, Manitoba, Canada.

PubMed

Hathout, S

2002-11-01

Most urban growth in Canada occurs in the urban-rural fringe. The increasing dispersal of the Canadian urban population is due to centrifugal forces pulling urbanites past the suburbs into the surrounding exurban communities. Most Canadian urban centres are located on prime agricultural land. Exurban sprawl devours an inordinate amount of the better agricultural land. The growth around the city of Winnipeg is a case in point. Within Winnipeg's urban field are the rural municipalities of East and West St Paul. The objective of this study is to investigate the impact of urban growth on the agricultural land of these RMs as well as the rate of urban growth in both Municipalities based on database analysis using aerial photographs taken in 1960 and 1989 and Geographic Information System (GIS). East St Paul was found to have a higher rate of urbanization (from 10.14% to 43.75%) between 1960 and 1989 than West St Paul (from 7.36% to 23.57%). The growth prediction using Markov probability chain analysis showed that East St Paul will henceforth experience a reduced rate of increase than West St Paul. The rate of urbanization for both RMs is found to be comparable with areas surrounding other major cities such as Toronto. The largest increases in urban land use categories occurred in and around the existing exurban settlements. It was found that most urbanization take place on the most fertile soil.

Exploring the Linkage between Urban Flood Risk and Spatial Patterns in Small Urbanized Catchments of Beijing, China

PubMed Central

Yao, Lei; Chen, Liding; Wei, Wei

2017-01-01

In the context of global urbanization, urban flood risk in many cities has become a serious environmental issue, threatening the health of residents and the environment. A number of hydrological studies have linked urban flooding issues closely to the spectrum of spatial patterns of urbanization, but relatively little attention has been given to small-scale catchments within the realm of urban systems. This study aims to explore the hydrological effects of small-scaled urbanized catchments assigned with various landscape patterns. Twelve typical residential catchments in Beijing were selected as the study areas. Total Impervious Area (TIA), Directly Connected Impervious Area (DCIA), and a drainage index were used as the catchment spatial metrics. Three scenarios were designed as different spatial arrangement of catchment imperviousness. Runoff variables including total and peak runoff depth (Qt and Qp) were simulated by using Strom Water Management Model (SWMM). The relationship between catchment spatial patterns and runoff variables were determined, and the results demonstrated that, spatial patterns have inherent influences on flood risks in small urbanized catchments. Specifically: (1) imperviousness acts as an effective indicator in affecting both Qt and Qp; (2) reducing the number of rainwater inlets appropriately will benefit the catchment peak flow mitigation; (3) different spatial concentrations of impervious surfaces have inherent influences on Qp. These findings provide insights into the role of urban spatial patterns in driving rainfall-runoff processes in small urbanized catchments, which is essential for urban planning and flood management. PMID:28264521

Examining Urban Expansion Using Multi-Temporal Landsat Imagery: a Case Study of the Montreal Census Metropolitan Area from 1975 TO 2015, Canada

NASA Astrophysics Data System (ADS)

Ma, Lingfei; Zhao, He; Li, Jonathan

2016-06-01

Urban expansion, particularly the movement of residential and commercial land use to sub-urban areas in metropolitan areas, has been considered as a significant signal of regional economic development. In 1970s, the economic centre of Canada moved from Montreal to Toronto. Since some previous research have been focused on the urbanization process in Greater Toronto Area (GTA), it is significant to conduct research in its counterpart. This study evaluates urban expansion process in Montréal census metropolitan area (CMA), Canada, between 1975 and 2015 using satellite images and socio-economic data. Spatial and temporal dynamic information of urbanization process was quantified using Landsat imagery, supervised classification algorithms and the post-classification change detection technique. Accuracy of the Landsat-derived land use classification map ranged from 80% to 97%. The results indicated that continuous growth of built-up areas in the CMA over the study period resulted in a decrease in the area of cultivated land and vegetation. The results showed that urban areas expanded 442 km2 both along major river systems and lakeshores, as well as expanded from urban centres to surrounded areas. The analysis revealed that urban expansion has been largely driven by population growth and economic development. Consequently, the urban expansion maps produced in this research can assist decision-makers to promote sustainable urban development, and forecast potential changes in urbanization growth patterns.

Challenges on Java’s small city spatial planning

NASA Astrophysics Data System (ADS)

Wirawan, B.; Tambunan, J. R.

2018-05-01

Most Indonesians nowadays live in the urban area, due to urbanization. 60 percent of the inhabitants of Java, the most populous island in Indonesia, will live in the urban area by 2010, a figure that is higher than the national average of 55 percent. Urbanization has brought a large influx of newcomers not only into the metropolitan or large cities, but also into small and medium cities. One of urbanization’s most concerning impacts is urban sprawl that harms sustainability. There is a dearth of academic literature studying the phenomenon of urban sprawl in Indonesian small cities. Urban sprawl in small cities is commonly ignored, considered as a contained problem the solution for which is a simple use of local spatial plan. Unfortunately, for Indonesia, this solution is difficult to implement because city spatial plans works only within administrative jurisdictions, whilst the urban sprawls themselves generally occur across the borders of different administrative jurisdictions. This study studies urban sprawls occurring in several small cities in Java. While those cities already have spatial plan, most were the general spatial plan (Rencana Tata Ruang Wilayah Kota/Kabupaten) that operates only within the city’s administrative jurisdiction. We are unable to find detailed strategies in these cities to deal with urban sprawl. We also found that all spatial plans are unable to come up with urban growth boundary strategy. Finally, we are also unable to find integrated detailed spatial plan among those cities to answer the urban sprawl situation.

Urban expansion brought stress to food security in China: Evidence from decreased cropland net primary productivity.

PubMed

He, Chunyang; Liu, Zhifeng; Xu, Min; Ma, Qun; Dou, Yinyin

2017-01-15

Cropland net primary productivity (CNPP) is a crucial indicator of grain productivity and food security. However, assessments of the impact of urban expansion on the CNPP in China have been inadequate owing to data limitations. In this paper, our objective was to assess the impact of urban expansion on the CNPP in China from 1992 to 2015 in a spatially explicit manner. We first obtained the CNPP before urban expansion between 1992 and 2015 in China using the Carnegie-Ames-Stanford Approach (CASA) model. We then assessed the impact of urban expansion on the CNPP from 1992 to 2015 at multiple scales (the whole country, agricultural zones, and urban expansion hotspots) by combining the CNPP before urban expansion with the urban land coverage time series extracted from multi-source remotely sensed data. We found that the total loss of the CNPP due to urban expansion from 1992 to 2015 was 13.77TgC, which accounts for 1.88% of the CNPP before urban expansion in China. This CNPP loss resulted in a 12.45-million-ton decrease in grain production in China, corresponding to a reduction in the mean annual grain self-sufficiency rate of 2%. Therefore, we concluded that rapid urban expansion from 1992 to 2015 caused stress to China's food security. We suggest that it is still vital for China to effectively protect cropland to improve the urbanization level to 60% by 2020. Copyright © 2016 Elsevier B.V. All rights reserved.

Global distribution and evolvement of urbanization and PM2.5 (1998-2015)

NASA Astrophysics Data System (ADS)

Yang, Dongyang; Ye, Chao; Wang, Xiaomin; Lu, Debin; Xu, Jianhua; Yang, Haiqing

2018-06-01

PM2.5 concentrations increased and have been one of the major social issues along with rapid urbanization in many regions of the world in recent decades. The development of urbanization differed among regions, PM2.5 pollution also presented discrepant distribution across the world. Thus, this paper aimed to grasp the profile of global distribution of urbanization and PM2.5 and their evolutionary relationships. Based on global data for the proportion of the urban population and PM2.5 concentrations in 1998-2015, this paper investigated the spatial distribution, temporal variation, and evolutionary relationships of global urbanization and PM2.5. The results showed PM2.5 presented an increasing trend along with urbanization during the study period, but there was a variety of evolutionary relationships in different countries and regions. Most countries in East Asia, Southeast Asia, South Asia, and some African countries developed with the rapid increase in both urbanization and PM2.5. Under the impact of other socioeconomic factors, such as industry and economic growth, the development of urbanization increased PM2.5 concentrations in most Asian countries and some African countries, but decreased PM2.5 concentrations in most European and American countries. The findings of this study revealed the spatial distributions of global urbanization and PM2.5 pollution and provided an interpretation on the evolution of urbanization-PM2.5 relationships, which can contribute to urbanization policies making aimed at successful PM2.5 pollution control and abatement.

Exploring the Linkage between Urban Flood Risk and Spatial Patterns in Small Urbanized Catchments of Beijing, China.

PubMed

Yao, Lei; Chen, Liding; Wei, Wei

2017-02-28

In the context of global urbanization, urban flood risk in many cities has become a serious environmental issue, threatening the health of residents and the environment. A number of hydrological studies have linked urban flooding issues closely to the spectrum of spatial patterns of urbanization, but relatively little attention has been given to small-scale catchments within the realm of urban systems. This study aims to explore the hydrological effects of small-scaled urbanized catchments assigned with various landscape patterns. Twelve typical residential catchments in Beijing were selected as the study areas. Total Impervious Area ( TIA ), Directly Connected Impervious Area ( DCIA ), and a drainage index were used as the catchment spatial metrics. Three scenarios were designed as different spatial arrangement of catchment imperviousness. Runoff variables including total and peak runoff depth ( Q t and Q p ) were simulated by using Strom Water Management Model (SWMM). The relationship between catchment spatial patterns and runoff variables were determined, and the results demonstrated that, spatial patterns have inherent influences on flood risks in small urbanized catchments. Specifically: (1) imperviousness acts as an effective indicator in affecting both Q t and Q p ; (2) reducing the number of rainwater inlets appropriately will benefit the catchment peak flow mitigation; (3) different spatial concentrations of impervious surfaces have inherent influences on Q p . These findings provide insights into the role of urban spatial patterns in driving rainfall-runoff processes in small urbanized catchments, which is essential for urban planning and flood management.

Influence of landscape mosaic on streamflow of a peri-urban catchment under Mediterranean climate

NASA Astrophysics Data System (ADS)

Ferreira, Carla; Walsh, Rory; Ferreira, António

2017-04-01

Peri-urban areas tend to be characterized by patchy landscape mosaics of different land-uses. Although the impact of land-use changes on catchment hydrology have been widely investigated, the impact of mixed land-use patterns on the streamflow of peri-urban areas is still poorly understood. This study aims to (i) explore and quantify streamflow delivery from sub-catchments characterized by distinct landscape mosaics; (ii) assess the impact of different urbanization styles on hydrograph properties; and (iii) explore the influence of urbanization type on flow connectivity and stream discharge. The study was carried out in Ribeira dos Covões, a small (6.2km2) peri-urban catchment in central Portugal. The climate is Mediterranean, with a mean annual rainfall of 892mm. Catchment geology comprises sandstone (56%), limestone (41%) and alluvial deposits (3%). Soils developed on sandstone are generally deep (>3m) Fluvisols and Podsols, whereas on limestone the Leptic Cambisols are typically shallow (<0.4m). Forest is the dominant land-use (56%), but urban areas cover an extensive area (40%), whereas agricultural land has declined to a very small area (4%). The urban area comprises contrasting urban styles, notably older discontinuous urban areas with buildings separated by gardens of low population density (<25 inhabitants km-2), and recent well-defined continuous urban cores dominated by apartment blocks and of high population density (9900 inhabitants km-2). The study uses hydrological data recorded over three hydrological years, starting in November 2010, in a monitoring network comprising eight streamflow gauging stations (instrumented with water level recorders) and five rainfall gauges. The gauging stations provide information on the discharge response to rainstorms of the catchment outlet and upstream sub-catchments of different size, urban pattern (in terms of percentage urban land-use and impervious area, distance to the stream network, and storm water management), and lithology (either sandstone or limestone). Annual storm runoff coefficients were lowest (13.7%) in catchments dominated by forest (>80%) and greatest (17.3-17.6%) in the most urbanized sub-catchments (49-53% urban). Impervious area seems to control streamflow particularly during dry periods. Winter runoff (streamflow per unit area) was 2-4 times higher than summer runoff in highly urbanized areas, but was 21-fold higher in winter than in summer in the least urbanized sub-catchment, indicating greater flow connectivity in winter, enhanced by increased soil moisture. Lithology also played an important role on hydrology, with sandstone sub-catchments exhibiting greater annual baseflow index values (23-46%) than found in limestone ones (<5%). For sub-catchments underlain by both lithologies, linear relationships were found between storm runoff coefficients and percentage urban and percentage impervious area, but with greater runoff responses in the sandstone ones. Nevertheless, linear regression lines for both lithologies get close to each other when the extent of urban areas reached about 50%. The proximity of urban areas to the stream network and whether urban storm runoff is directly piped to the stream network were important parameters influencing peak flows and response time. Landscape mosaics that include land-use patches of high soil permeability tend to provide locations of surface water retention and enhanced infiltration, thereby breaking flow connectivity between hillslope urban surfaces and the stream network. This kind of spatial pattern should be considered for urban planning, in order to minimize flood hazards.

Systematic flood modelling to support flood-proof urban design

NASA Astrophysics Data System (ADS)

Bruwier, Martin; Mustafa, Ahmed; Aliaga, Daniel; Archambeau, Pierre; Erpicum, Sébastien; Nishida, Gen; Zhang, Xiaowei; Pirotton, Michel; Teller, Jacques; Dewals, Benjamin

2017-04-01

Urban flood risk is influenced by many factors such as hydro-meteorological drivers, existing drainage systems as well as vulnerability of population and assets. The urban fabric itself has also a complex influence on inundation flows. In this research, we performed a systematic analysis on how various characteristics of urban patterns control inundation flow within the urban area and upstream of it. An urban generator tool was used to generate over 2,250 synthetic urban networks of 1 km2. This tool is based on the procedural modelling presented by Parish and Müller (2001) which was adapted to generate a broader variety of urban networks. Nine input parameters were used to control the urban geometry. Three of them define the average length, orientation and curvature of the streets. Two orthogonal major roads, for which the width constitutes the fourth input parameter, work as constraints to generate the urban network. The width of secondary streets is given by the fifth input parameter. Each parcel generated by the street network based on a parcel mean area parameter can be either a park or a building parcel depending on the park ratio parameter. Three setback parameters constraint the exact location of the building whithin a building parcel. For each of synthetic urban network, detailed two-dimensional inundation maps were computed with a hydraulic model. The computational efficiency was enhanced by means of a porosity model. This enables the use of a coarser computational grid , while preserving information on the detailed geometry of the urban network (Sanders et al. 2008). These porosity parameters reflect not only the void fraction, which influences the storage capacity of the urban area, but also the influence of buildings on flow conveyance (dynamic effects). A sensitivity analysis was performed based on the inundation maps to highlight the respective impact of each input parameter characteristizing the urban networks. The findings of the study pinpoint which properties of urban networks have a major influence on urban inundation flow, enabling better informed flood-proof urban design. References: Parish, Y. I. H., Muller, P. 2001. Procedural modeling of cities. SIGGRAPH, pp. 301—308. Sanders, B.F., Schubert, J.E., Gallegos, H.A., 2008. Integral formulation of shallow-water equations with anisotropic porosity for urban flood modeling. Journal of Hydrology 362, 19-38. Acknowledgements: The research was funded through the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation.

The application of remote sensing techniques to selected inter and intra urban data acquisition problems

NASA Technical Reports Server (NTRS)

Horton, F. E.

1970-01-01

The utility of remote sensing techniques to urban data acquisition problems in several distinct areas was identified. This endeavor included a comparison of remote sensing systems for urban data collection, the extraction of housing quality data from aerial photography, utilization of photographic sensors in urban transportation studies, urban change detection, space photography utilization, and an application of remote sensing techniques to the acquisition of data concerning intra-urban commercial centers. The systematic evaluation of variable extraction for urban modeling and planning at several different scales, and the model derivation for identifying and predicting economic growth and change within a regional system of cities are also studied.

Applications of Green Walls in Urban Design

NASA Astrophysics Data System (ADS)

Virtudes, Ana; Manso, Maria

2016-10-01

Green walls are a choice towards achieving sustainable urban rehabilitation, due to the lack of free space in the consolidated urban fabric. Nowadays, green walls are considered to be an innovation in the fields of ecology, horticulture or buildings. Nevertheless, in the domain of urban design, they are still surprising and unexpected ideas. Thus, this research aims to reflect on green walls as a feature in urban design and rehabilitation, identifying the advantages of their utilization as an enhancement of the quality of city's image, especially in dense urban areas. It aims to demonstrate some practical applications of green walls in urban design proposals, showing model solutions and their real application in several architectural examples.

Location or Hukou: What Most Limits Fertility of Urban Women in China?

PubMed Central

Liang, Yun

2017-01-01

Abstract China's fertility rate is below replacement level. The government is attempting to increase this rate by relaxing the one‐child policy. China faces a possible tradeoff because further urbanization is needed to raise incomes but may reduce future fertility. We decompose China's rural–urban fertility gaps using both de facto and de jure criteria for defining the urban population. The fertility‐depressing effects of holding urban hukou are more than three times larger than effects of urban residence. Less of the rural–urban fertility gap by hukou status is due to differences in characteristics than is the case for the fertility gap by place of residence. PMID:29081975

Experiences That Predict Early Career Teacher Commitment to and Retention in High-Poverty Urban Schools

ERIC Educational Resources Information Center

Whipp, Joan L.; Geronime, Lara

2017-01-01

Correlation analysis was used to analyze what experiences before and during teacher preparation for 72 graduates of an urban teacher education program were associated with urban commitment, first job location, and retention in urban schools for 3 or more years. Binary logistic regression was then used to analyze whether urban K-12 schooling,…

An Alternative Curriculum Model for Urban Education and Community Affairs Programs in Higher Education. Working Paper No. 103.

ERIC Educational Resources Information Center

Simmons, Ron

This document describes the urban education program at William Paterson College of New Jersey. Urban education is defined as educating people for living and in coping with an urban environment, including politics, crime and drug prevention, and delivery of services to cities. Some problems in urban education are identified as weak…

Urban and rural land use in Puerto Rico

Treesearch

Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez; Maya Quinones; Michael E. Jimenez

2008-01-01

We have developed three land use regions for Puerto Rico: Urban, Suburban, and Rural (Gould et al. 2008; Martinuzzi et al. 2007). These three regions can also be considered urban, densely-populated rural, and sparsely-populated rural or as urban and wildland with a wildland-urban interface. The suburban use is the most dynamic in terms of population growth and land...

Urban foraging: a ubiquitous human practice overlooked by urban planners, policy, and research

Treesearch

Charlie Shackleton; Patrick Hurley; Annika Dahlberg; Marla Emery; Harini Nagendra

2017-01-01

Although hardly noticed or formally recognised, urban foraging by humans probably occurs in all urban settings around the world. We draw from research in India, South Africa, Sweden, and the United States to demonstrate the ubiquity and varied nature of urban foraging in different contexts. Across these different contexts, we distil seven themes that characterise and...

40 CFR 85.1404 - Maintenance of records for urban bus operators; submittal of information; right of entry.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Maintenance of records for urban bus... SOURCES Urban Bus Rebuild Requirements § 85.1404 Maintenance of records for urban bus operators; submittal of information; right of entry. (a) The operator of any urban bus for which this subpart is...

40 CFR 85.1404 - Maintenance of records for urban bus operators; submittal of information; right of entry.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Maintenance of records for urban bus... SOURCES Urban Bus Rebuild Requirements § 85.1404 Maintenance of records for urban bus operators; submittal of information; right of entry. (a) The operator of any urban bus for which this subpart is...

40 CFR 85.1404 - Maintenance of records for urban bus operators; submittal of information; right of entry.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Maintenance of records for urban bus... SOURCES Urban Bus Rebuild Requirements § 85.1404 Maintenance of records for urban bus operators; submittal of information; right of entry. (a) The operator of any urban bus for which this subpart is...

40 CFR 85.1404 - Maintenance of records for urban bus operators; submittal of information; right of entry.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Maintenance of records for urban bus... SOURCES Urban Bus Rebuild Requirements § 85.1404 Maintenance of records for urban bus operators; submittal of information; right of entry. (a) The operator of any urban bus for which this subpart is...

Emerging issues in urban ecology: implications for research, social justice, human health, and well-being

Treesearch

Viniece Jennings; Myron F. Floyd; Danielle Shanahan; Christopher Coutts; Alex Sinykin

2017-01-01

Urbanization affects landscape structure and the overall human condition in numerous ways. Green spaces include vegetated land cover (e.g., urban forests, trees, riparian zones, parks) which play a distinctive role in urban ecology. This article reviews emergent literature on the linkages between urban green spaces, social justice, and human health. We explore this...

Teaching Urban Sociology and Urban Sustainability on Two Feet, Two Wheels, and in Three Cities: Our Experience Teaching Sustainable Cities in North America

ERIC Educational Resources Information Center

Christiansen, Lars; Fischer, Nancy

2010-01-01

The authors describe their experiences teaching Sustainable Cities in North America, a course on both urban sociology and urban sustainability. This course brought students to Portland, Oregon, and Vancouver, British Columbia, and then compared those cities with Minneapolis, Minnesota, on various dimensions of urban sustainability. After…

School Enrollment among Urban Non-Slum, Slum and Rural Children in Kenya: Is the Urban Advantage Eroding?

ERIC Educational Resources Information Center

Mugisha, Frederick

2006-01-01

For long now, the urban child has been considered to be more likely than his/her rural counterpart in being able to realize the dream of fully participating in school. This observation has mainly been attributed to what is commonly known as the "urban advantage." This "urban advantage" is associated with increased access to…

Urban ecosystems and the North American carbon cycle

Treesearch

D.E. Pataki; R.J. Alig; A.S. Fung; N.E. Golubiewski; C.A. Kennedy; E.G. McPherson; D.J. Nowak; R.V. Pouyat; P.R. Lankao

2006-01-01

Approximately 75–80% of the population of North America currently lives in urban areas as defined by national census bureaus, and urbanization is continuing to increase. Future trajectories of fossil fuel emissions are associated with a high degree of uncertainty; however, if the activities of urban residents and the rate of urban land conversion can be captured in...

Temporal dynamics of a subtropical urban forest in San Juan, Puerto Rico, 2001-2010

Treesearch

J. M. Tucker Lima; C. L. Staudhammer; T. J. Brandeis; F. J. Escobedo; W. Zipperer

2013-01-01

Several studies report urban tree growth and mortality rates as well as species composition, structural dynamics, and other characteristics of urban forests in mostly temperate, inland urban areas. Temporal dynamics of urban forests in subtropical and tropical forest regions are, until now, little explored and represent a new and important direction for study and...

Response of forest soil properties to urbanization gradients in three metropolitan areas

Treesearch

Richard V. Pouyat; Ian D. Yesilonis; Katalin Szlavecz; Csaba Csuzdi; Elizabeth Hornung; Zoltan Kors& #243; s; Jonathan Russell-Anelli; Vincent Giorgio

2008-01-01

We investigated the effects of urban environments on the chemical properties of forest soils in the metropolitan areas of Baltimore, New York, and Budapest. We hypothesized that soils in forest patches in each city will exhibit changes in chemistry corresponding to urbanization gradients, but more strongly with various urban metrics than distance to the urban core....

Variability in urban soils influences the health and growth of native tree seedlings

Treesearch

Clara C. Pregitzer; Nancy F. Sonti; Richard A. Hallett

2016-01-01

Reforesting degraded urban landscapes is important due to the many benefits urban forests provide. Urban soils are highly variable, yet little is known about how this variability in urban soils influences tree seedling performance and survival. We conducted a greenhouse study to assess health, growth, and survival of four native tree species growing in native glacial...

Urban Watershed Forestry Manual Part 3: Urban Tree Planting Guide

Treesearch

Karen Cappiella; Tom Schueler; Tiffany Wright; Jennifer Tomlinson

2006-01-01

This is the third in a three-manual series on using trees to protect and restore urban watersheds. A brief description of each part follows. Part 3. Urban Tree Planting Guide provides detailed guidance on urban tree planting that is applicable at both the development site and the watershed scales. Topics covered include site assessment, planting design, site...

Urban Crowns: crown analysis software to assist in quantifying urban tree benefits

Treesearch

Matthew F. Winn; Sang-Mook Lee Bradley; Philip A. Araman

2010-01-01

UrbanCrowns is a Microsoft® Windows®-based computer program developed by the U.S. Forest Service Southern Research Station. The software assists urban forestry professionals, arborists, and community volunteers in assessing and monitoring the crown characteristics of urban trees (both deciduous and coniferous) using a single side-view digital photograph. Program output...

A Study of an Inter-Institutional Partnership between an Urban Community College and an Urban Public School District

ERIC Educational Resources Information Center

Gaines, Michael L.

2012-01-01

This study examined the unique partnership between Midwest Community College and Urban Public Schools' Urban Career Technical High School. The Urban Technical High School (UTHS) is designed to provide students interested in Tech Prep education a clear pathway from high school to college. Through collaboration, services were provided to assist high…

Hydrology for urban land planning - A guidebook on the hydrologic effects of urban land use

USGS Publications Warehouse

Leopold, Luna Bergere

1968-01-01

The application of current knowledge of the hydrologic effects of urbanization to the Brandywine should be viewed as a forecast of conditions which may be expected as urbanization proceeds. By making such forecasts in advance of actual urban development, the methods can be tested, data can be extended, and procedures improved as verification becomes possible.

Degree of adaptive response in urban tolerant birds shows influence of habitat-of-origin

PubMed Central

2014-01-01

Urban exploiters and adapters are often coalesced under a term of convenience as ‘urban tolerant’. This useful but simplistic characterisation masks a more nuanced interplay between and within assemblages of birds that are more or less well adapted to a range of urban habitats. I test the hypotheses that objectively-defined urban exploiter and suburban adapter assemblages within the broad urban tolerant grouping in Melbourne vary in their responses within the larger group to predictor variables, and that the most explanatory predictor variables vary between the two assemblages. A paired, partitioned analysis of exploiter and adapter preferences for points along the urban–rural gradient was undertaken to decompose the overall trend into diagnosable parts for each assemblage. In a similar way to that in which time since establishment has been found to be related to high urban densities of some bird species and biogeographic origin predictive of urban adaptation extent, habitat origins of members of bird assemblages influence the degree to which they become urban tolerant. Bird species that objectively classify as urban tolerant will further classify as either exploiters or adapters according to the degree of openness of their habitats-of-origin. PMID:24688881

Relation Decomposing between Urbanization and Consumption of Water-Energy Sources

NASA Astrophysics Data System (ADS)

Wang, Y.; Xiao, W.; Wang, Y.; Zhao, Y.; Wang, J., , Dr; Jiang, D.; Wang, H.

2017-12-01

Abstract: Water resources and energy, important subsystems of city, are the basic guarantee for the normal operation of city, which play an important role to brace the urbanization. The interdependence between them are increasing along with the rapid development of China's economy. The relationship between urbanization and consumption of energy and water have become the focal point of the scholars, but the research have more attention to the impact of urbanization on two subsystems separately, and do not reveal the effects of urbanization on the water-energy nexus. Thus, there is little consideration upon the different characteristics of China's several regions in water and energy consumption in urbanization. In this paper, the STIRPAT model is built to reveal the relationship between urbanization and the consumption of water and energy. Also, the influence of urbanization on different main body of water and energy consumption are discussed. The different regional main factors of water and energy in the process of urbanization are identified through water and energy panel data of China's thirty provinces. Finally, through the regression analysis of total water consumption data of agriculture, industry, service industry with total energy consumption data, the relationship of water and energy in the process of urban development are analyzed.

Signatures of Rapid Evolution in Urban and Rural Transcriptomes of White-Footed Mice (Peromyscus leucopus) in the New York Metropolitan Area

PubMed Central

Harris, Stephen E.; Munshi-South, Jason; Obergfell, Craig; O’Neill, Rachel

2013-01-01

Urbanization is a major cause of ecological degradation around the world, and human settlement in large cities is accelerating. New York City (NYC) is one of the oldest and most urbanized cities in North America, but still maintains 20% vegetation cover and substantial populations of some native wildlife. The white-footed mouse, Peromyscus leucopus , is a common resident of NYC’s forest fragments and an emerging model system for examining the evolutionary consequences of urbanization. In this study, we developed transcriptomic resources for urban P . leucopus to examine evolutionary changes in protein-coding regions for an exemplar “urban adapter.” We used Roche 454 GS FLX+ high throughput sequencing to derive transcriptomes from multiple tissues from individuals across both urban and rural populations. From these data, we identified 31,015 SNPs and several candidate genes potentially experiencing positive selection in urban populations of P . leucopus . These candidate genes are involved in xenobiotic metabolism, innate immune response, demethylation activity, and other important biological phenomena in novel urban environments. This study is one of the first to report candidate genes exhibiting signatures of directional selection in divergent urban ecosystems. PMID:24015321

Proceedings of the workshop on urban freight consolidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1978-06-01

The Urban Freight Consolidation Workshop discusses the desirability and practicality of establishing programs to consolidate the pickup and delivery of small shipments in highly concentrated urban areas. After presentation of an overview paper, Institutional Issues in Urban Freight Consolidation, by Ernest R. Cadotte and Robert A. Robicheaux, the following papers were given: Consolidation and Distribution--The Broad Picture, John T. Norris; Transportation Facilitation Center Concept, Irwin Blatner; The Regulatory Issues of Small-Shipment Consolidation, A. Daniel O'Neal; Chicago's Perspective of Urban-Freight Consolidation, Charles W. Lustig; Freight Consolidation in New York City, Samuel D. Kahan; Baltimore's Perspective of Urban-Freight Consolidation, Siegbert Schacknies; Small-Shippermore » Perspective, Richard A. Whitty; The Perspective of a ''Big Shipper,'' William K. Smith; A Receiver's Viewpoint of Consolidation, William P. McDaniel; For-Hire Motor-Carrier Perspective of Urban-Freight Consolidation, John L. Reith; Private-Carrier Perspective of Urban-Freight Consolidation, H. E. Manker; Union Perspective, M. R. Nensel; Urban-Freight Distribution Myopia, Carl S. Rappaport; Freight-Service Expectations, Performance, and Tradeoffs in Urban Areas: A Survey, Robert A. Robicheaux and Ernest R. Cadotte; and Freight Consolidation--Can It Be Successfully Implemented, James F. Robeson. (MCW)« less

Urbanization and its implications for food and farming.

PubMed

Satterthwaite, David; McGranahan, Gordon; Tacoli, Cecilia

2010-09-27

This paper discusses the influences on food and farming of an increasingly urbanized world and a declining ratio of food producers to food consumers. Urbanization has been underpinned by the rapid growth in the world economy and in the proportion of gross world product and of workers in industrial and service enterprises. Globally, agriculture has met the demands from this rapidly growing urban population, including food that is more energy-, land-, water- and greenhouse gas emission-intensive. But hundreds of millions of urban dwellers suffer under-nutrition. So the key issues with regard to agriculture and urbanization are whether the growing and changing demands for agricultural products from growing urban populations can be sustained while at the same time underpinning agricultural prosperity and reducing rural and urban poverty. To this are added the need to reduce greenhouse gas emissions and to build resilience in agriculture and urban development to climate change impacts. The paper gives particular attention to low- and middle-income nations since these have more than three-quarters of the world's urban population and most of its largest cities and these include nations where issues of food security are most pressing.

Diurnal changes in urban boundary layer environment induced by urban greening

NASA Astrophysics Data System (ADS)

Song, Jiyun; Wang, Zhi-Hua

2016-11-01

Urban green infrastructure has been widely used for mitigating adverse environmental problems as well as enhancing urban sustainability of cities worldwide. Here we develop an integrated urban-land-atmosphere modeling framework with the land surface processes parameterized by an advanced urban canopy model and the atmospheric processes parameterized by a single column model. The model is then applied to simulate a variety of forms of green infrastructure, including urban lawns, shade trees, green and cool roofs, and their impact on environmental changes in the total urban boundary layer (UBL) for a stereotypical desert city, viz. Phoenix, Arizona. It was found that green roofs have a relatively uniform cooling effect proportional to their areal coverage. In particular, a reduction of UBL temperature of 0.3 °C and 0.2 °C per 10% increase of green roof coverage was observed at daytime and nighttime, respectively. In contrast, the effect of greening of street canyons is constrained by the overall abundance of green infrastructure and the energy available for evapotranspiration. In addition, the increase in urban greening causes boundary-layer height to decrease during daytime but increase at nighttime, leading to different trends of changes in urban air quality throughout a diurnal cycle.

[A landscape ecological approach for urban non-point source pollution control].

PubMed

Guo, Qinghai; Ma, Keming; Zhao, Jingzhu; Yang, Liu; Yin, Chengqing

2005-05-01

Urban non-point source pollution is a new problem appeared with the speeding development of urbanization. The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution, and more difficult to control. Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution, mainly adopting local repairing practices to control the pollutants in surface runoff. Because of the close relationship between urban land use patterns and non-point source pollution, it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution, which needs, firstly, analyzing and evaluating the influence of landscape structure on water-bodies, pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields, and secondly, adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern, and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.

Nowhere safe? Exploring the influence of urbanization across mainland and insular seashores in continental Portugal and the Azorean Archipelago.

PubMed

Bertocci, Iacopo; Arenas, Francisco; Cacabelos, Eva; Martins, Gustavo M; Seabra, Maria I; Álvaro, Nuno V; Fernandes, Joana N; Gaião, Raquel; Mamede, Nuno; Mulas, Martina; Neto, Ana I

2017-01-30

Differences in the structure and functioning of intensively urbanized vs. less human-affected systems are reported, but such evidence is available for a much larger extent in terrestrial than in marine systems. We examined the hypotheses that (i) urbanization was associated to different patterns of variation of intertidal assemblages between urban and extra-urban environments; (ii) such patterns were consistent across mainland and insular systems, spatial scales from 10scm to 100skm, and a three months period. Several trends emerged: (i) a more homogeneous distribution of most algal groups in the urban compared to the extra-urban condition and the opposite pattern of most invertebrates; (ii) smaller/larger variances of most organisms where these were, respectively, less/more abundant; (iii) largest variability of most response variables at small scale; (iv) no facilitation of invasive species by urbanization and larger cover of canopy-forming algae in the insular extra-urban condition. Present findings confirm the acknowledged notion that future management strategies will require to include representative assemblages and their relevant scales of variation associated to urbanization gradients on both the mainland and the islands. Copyright © 2016 Elsevier Ltd. All rights reserved.

Urbanization prolongs hantavirus epidemics in cities

PubMed Central

Tian, Huaiyu; Hu, Shixiong; Chowell, Gerardo; Gao, Lidong; Li, Yapin; Yang, Huisuo; Li, Yidan; Yang, Qiqi; Tong, Xin; Huang, Ru; Bjornstad, Ottar N.; Xiao, Hong; Stenseth, Nils Chr.

2018-01-01

Urbanization and rural–urban migration are two factors driving global patterns of disease and mortality. There is significant concern about their potential impact on disease burden and the effectiveness of current control approaches. Few attempts have been made to increase our understanding of the relationship between urbanization and disease dynamics, although it is generally believed that urban living has contributed to reductions in communicable disease burden in industrialized countries. To investigate this relationship, we carried out spatiotemporal analyses using a 48-year-long dataset of hemorrhagic fever with renal syndrome incidence (HFRS; mainly caused by two serotypes of hantavirus in China: Hantaan virus and Seoul virus) and population movements in an important endemic area of south China during the period 1963–2010. Our findings indicate that epidemics coincide with urbanization, geographic expansion, and migrant movement over time. We found a biphasic inverted U-shaped relationship between HFRS incidence and urbanization, with various endemic turning points associated with economic growth rates in cities. Our results revealed the interrelatedness of urbanization, migration, and hantavirus epidemiology, potentially explaining why urbanizing cities with high economic growth exhibit extended epidemics. Our results also highlight contrasting effects of urbanization on zoonotic disease outbreaks during periods of economic development in China. PMID:29666240

Reproduction and survival in the city: which fitness components drive urban colonization in a reed-nesting waterbird?

PubMed Central

Minias, Piotr

2016-01-01

Abstract Processes of adaptation to urban environments are well described for relatively few avian taxa, mainly passerines, but selective forces responsible for urban colonization in ecologically different groups of birds remain mostly unrecognized. The aim of this article is to identify drivers of recent urban colonization (Łódź, central Poland) by a reed-nesting waterbird, the Eurasian coot Fulica atra. Urban colonizers were found to adopt a distinct reproductive strategy by maximizing the number of offspring (carryover effects of higher clutch size), whereas suburban individuals invested more in the quality of the progeny (higher egg volume), which could reflect differences in predatory pressure between 2 habitats. In fact, reduced predation rate was strongly suggested by elevated hatching success in highly urbanized areas, where probability of hatching at least 1 chick was higher by 30% than in suburban natural-like habitats. Coots nesting in highly urbanized landscape had considerably higher annual reproductive success in comparison to suburban pairs, and the difference was 4-fold between the most and least urbanized areas. There was also a constant increase in size-adjusted body mass and hemoglobin concentration of breeding coots from the suburbs to the city centre. Urban colonization yielded no survival benefits for adult birds and urban individuals showed higher site fidelity than suburban conspecifics. The results suggest that the recent urban colonization by Eurasian coots was primary driven by considerable reproductive benefits which may be primarily attributed to: (1) reduced predation resulting from an exclusion of most native predators from highly urbanized zones; (2) increased condition of urban-dwelling birds resulting from enhanced food availability. PMID:29491894

Benefits of explicit urban parameterization in regional climate modeling to study climate and city interactions

NASA Astrophysics Data System (ADS)

Daniel, M.; Lemonsu, Aude; Déqué, M.; Somot, S.; Alias, A.; Masson, V.

2018-06-01

Most climate models do not explicitly model urban areas and at best describe them as rock covers. Nonetheless, the very high resolutions reached now by the regional climate models may justify and require a more realistic parameterization of surface exchanges between urban canopy and atmosphere. To quantify the potential impact of urbanization on the regional climate, and evaluate the benefits of a detailed urban canopy model compared with a simpler approach, a sensitivity study was carried out over France at a 12-km horizontal resolution with the ALADIN-Climate regional model for 1980-2009 time period. Different descriptions of land use and urban modeling were compared, corresponding to an explicit modeling of cities with the urban canopy model TEB, a conventional and simpler approach representing urban areas as rocks, and a vegetated experiment for which cities are replaced by natural covers. A general evaluation of ALADIN-Climate was first done, that showed an overestimation of the incoming solar radiation but satisfying results in terms of precipitation and near-surface temperatures. The sensitivity analysis then highlighted that urban areas had a significant impact on modeled near-surface temperature. A further analysis on a few large French cities indicated that over the 30 years of simulation they all induced a warming effect both at daytime and nighttime with values up to + 1.5 °C for the city of Paris. The urban model also led to a regional warming extending beyond the urban areas boundaries. Finally, the comparison to temperature observations available for Paris area highlighted that the detailed urban canopy model improved the modeling of the urban heat island compared with a simpler approach.

Urban emissions of water vapor in winter

NASA Astrophysics Data System (ADS)

Salmon, Olivia E.; Shepson, Paul B.; Ren, Xinrong; Marquardt Collow, Allison B.; Miller, Mark A.; Carlton, Annmarie G.; Cambaliza, Maria O. L.; Heimburger, Alexie; Morgan, Kristan L.; Fuentes, Jose D.; Stirm, Brian H.; Grundman, Robert; Dickerson, Russell R.

2017-09-01

Elevated water vapor (H2Ov) mole fractions were occasionally observed downwind of Indianapolis, IN, and the Washington, D.C.-Baltimore, MD, area during airborne mass balance experiments conducted during winter months between 2012 and 2015. On days when an urban H2Ov excess signal was observed, H2Ov emission estimates range between 1.6 × 104 and 1.7 × 105 kg s-1 and account for up to 8.4% of the total (background + urban excess) advected flow of atmospheric boundary layer H2Ov from the urban study sites. Estimates of H2Ov emissions from combustion sources and electricity generation facility cooling towers are 1-2 orders of magnitude smaller than the urban H2Ov emission rates estimated from observations. Instances of urban H2Ov enhancement could be a result of differences in snowmelt and evaporation rates within the urban area, due in part to larger wintertime anthropogenic heat flux and land cover differences, relative to surrounding rural areas. More study is needed to understand why the urban H2Ov excess signal is observed on some days, and not others. Radiative transfer modeling indicates that the observed urban enhancements in H2Ov and other greenhouse gas mole fractions contribute only 0.1°C d-1 to the urban heat island at the surface. This integrated warming through the boundary layer is offset by longwave cooling by H2Ov at the top of the boundary layer. While the radiative impacts of urban H2Ov emissions do not meaningfully influence urban heat island intensity, urban H2Ov emissions may have the potential to alter downwind aerosol and cloud properties.

Urbanization effects on stream habitat characteristics in Boston, Massachusetts; Birmingham, Alabama; and Salt Lake City, Utah

USGS Publications Warehouse

Short, T.M.; Giddings, E.M.P.; Zappia, H.; Coles, J.F.

2005-01-01

Relations between stream habitat and urban land-use intensity were examined in 90 stream reaches located in or near the metropolitan areas of Salt Lake City, Utah (SLC); Birmingham, Alabama (BIR); and Boston, Massachusetts (BOS). Urban intensity was based on a multi-metric index (urban intensity index or UII) that included measures of land cover, socioeconomic organization, and urban infrastructure. Twenty-eight physical variables describing channel morphology, hydraulic properties, and streambed conditions were examined. None of the habitat variables was significantly correlated with urbanization intensity in all three study areas. Urbanization effects on stream habitat were less apparent for streams in SLC and BIR, owing to the strong influence of basin slope (SLC) and drought conditions (BIR) on local flow regimes. Streamflow in the BOS study area was not unduly influenced by similar conditions of climate and physiography, and habitat conditions in these streams were more responsive to urbanization. Urbanization in BOS contributed to higher discharge, channel deepening, and increased loading of fine-grained particles to stream channels. The modifying influence of basin slope and climate on hydrology of streams in SLC and BIR limited our ability to effectively compare habitat responses among different urban settings and identify common responses that might be of interest to restoration or water management programs. Successful application of land-use models such as the UII to compare urbanization effects on stream habitat in different environmental settings must account for inherent differences in natural and anthropogenic factors affecting stream hydrology and geomorphology. The challenge to future management of urban development is to further quantify these differences by building upon existing models, and ultimately develop a broader understanding of urbanization effects on aquatic ecosystems. ?? 2005 by the American Fisheries Society.

Wintertime urban heat island modified by global climate change over Japan

NASA Astrophysics Data System (ADS)

Hara, M.

2015-12-01

Urban thermal environment change, especially, surface air temperature (SAT) rise in metropolitan areas, is one of the major recent issues in urban areas. The urban thermal environmental change affects not only human health such as heat stroke, but also increasing infectious disease due to spreading out virus vectors habitat and increase of industry and house energy consumption. The SAT rise is mostly caused by global climate change and urban heat island (hereafter UHI) by urbanization. The population in Tokyo metropolitan area is over 30 millions and the Tokyo metropolitan area is one of the biggest megacities in the world. The temperature rise due to urbanization seems comparable to the global climate change in the major megacities. It is important to project how the urbanization and the global climate change affect to the future change of urban thermal environment to plan the adaptation and mitigation policy. To predict future SAT change in urban scale, we should estimate future UHI modified by the global climate change. This study investigates change in UHI intensity (UHII) of major metropolitan areas in Japan by effects of the global climate change. We performed a series of climate simulations. Present climate simulations with and without urban process are conducted for ten seasons using a high-resolution numerical climate model, the Weather Research and Forecasting (WRF) model. Future climate projections with and without urban process are also conducted. The future projections are performed using the pseudo global warming method, assuming 2050s' initial and boundary conditions estimated by a GCM under the RCP scenario. Simulation results indicated that UHII would be enhanced more than 30% in Tokyo during the night due to the global climate change. The enhancement of urban heat island is mostly caused by change of lower atmospheric stability.

How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis.

PubMed

Xu, Min; He, Chunyang; Liu, Zhifeng; Dou, Yinyin

2016-01-01

Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth-infilling, edge expansion, and leapfrog-edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China.

External contribution to urban air pollution.

PubMed

Grima, Ramon; Micallef, Alfred; Colls, Jeremy J

2002-02-01

Elevated particulate matter concentrations in urban locations have normally been associated with local traffic emissions. Recently it has been suggested that such episodes are influenced to a high degree by PM10 sources external to urban areas. To further corroborate this hypothesis, linear regression was sought between PM10 concentrations measured at eight urban sites in the U.K., with particulate sulphate concentration measured at two rural sites, for the years 1993-1997. Analysis of the slopes, intercepts and correlation coefficients indicate a possible relationship between urban PM10 and rural sulphate concentrations. The influences of wind direction and of the distance of the urban from the rural sites on the values of the three statistical parameters are also explored. The value of linear regression as an analysis tool in such cases is discussed and it is shown that an analysis of the sign of the rate of change of the urban PM10 and rural sulphate concentrations provides a more realistic method of correlation. The results indicate a major influence on urban PM10 concentrations from the eastern side of the United Kingdom. Linear correlation was also sought using PM10 data from nine urban sites in London and nearby rural Rochester. Analysis of the magnitude of the gradients and intercepts together with episode correlation analysis between the two sites showed the effect of transported PM10 on the local London concentrations. This article also presents methods to estimate the influence of rural and urban PM10 sources on urban PM10 concentrations and to obtain a rough estimate of the transboundary contribution to urban air pollution from the PM10 concentration data of the urban site.

Mapping and modeling the urban landscape in Bangkok, Thailand: Physical-spectral-spatial relations of population-environmental interactions

NASA Astrophysics Data System (ADS)

Shao, Yang

This research focuses on the application of remote sensing, geographic information systems, statistical modeling, and spatial analysis to examine the dynamics of urban land cover, urban structure, and population-environment interactions in Bangkok, Thailand, with an emphasis on rural-to-urban migration from rural Nang Rong District, Northeast Thailand to the primate city of Bangkok. The dissertation consists of four main sections: (1) development of remote sensing image classification and change-detection methods for characterizing imperviousness for Bangkok, Thailand from 1993-2002; (2) development of 3-D urban mapping methods, using high spatial resolution IKONOS satellite images, to assess high-rises and other urban structures; (3) assessment of urban spatial structure from 2-D and 3-D perspectives; and (4) an analysis of the spatial clustering of migrants from Nang Rong District in Bangkok and the neighborhood environments of migrants' locations. Techniques are developed to improve the accuracy of the neural network classification approach for the analysis of remote sensing data, with an emphasis on the spectral unmixing problem. The 3-D building heights are derived using the shadow information on the high-resolution IKONOS image. The results from the 2-D and 3-D mapping are further examined to assess urban structure and urban feature identification. This research contributes to image processing of remotely-sensed images and urban studies. The rural-urban migration process and migrants' settlement patterns are examined using spatial statistics, GIS, and remote sensing perspectives. The results show that migrants' spatial clustering in urban space is associated with the source village and a number of socio-demographic variables. In addition, the migrants' neighborhood environments in urban setting are modeled using a set of geographic and socio-demographic variables, and the results are scale-dependent.

The implementation of biofiltration systems, rainwater tanks and urban irrigation in a single-layer urban canopy model

NASA Astrophysics Data System (ADS)

Demuzere, Matthias; Coutts, Andrew; Goehler, Maren; Broadbent, Ashley; Wouters, Hendrik; van Lipzig, Nicole; Gebert, Luke

2015-04-01

Urban vegetation is generally considered as a key tool to modify the urban energy balance through enhanced evapotranspiration (ET). Given that vegetation is most effective when it is healthy, stormwater harvesting and retention strategies (such as water sensitive urban design) could be used to support vegetation and promote ET. This study presents the implementation of a vegetated lined bio-filtration system (BFS) combined with a rainwater tank (RWT) and urban irrigation system in the single-layer urban canopy model Community Land Model-Urban. Runoff from roof and impervious road surface fractions is harvested and used to support an adequate soil moisture level for vegetation in the BFS. In a first stage, modelled soil moisture dynamics are evaluated and found reliable compared to observed soil moisture levels from biofiltration pits in Smith Street, Melbourne (Australia). Secondly, the impact of BFS, RWT and urban irrigation on ET is illustrated for a two-month period in 2012 using varying characteristics for all components. Results indicate that (i) a large amount of stormwater is potentially available for indoor and outdoor water demands, including irrigation of urban vegetation, (ii) ET from the BFS is an order of magnitude larger compared to the contributions from the impervious surfaces, even though the former only covers 10% of the surface fraction and (iii) attention should be paid to the cover fraction and soil texture of the BFS, size of the RWT and the surface fractions contributing to the collection of water in the RWT. Overall, this study reveals that this model development can effectuate future research with state-of-the-art urban climate models to further explore the benefits of vegetated biofiltration systems as a water sensitive urban design tool optimised with an urban irrigation system to maintain healthy vegetation.

Effect of place of residence and treatment on survival outcomes in patients with diffuse large B-cell lymphoma in British Columbia.

PubMed

Lee, Benny; Goktepe, Ozge; Hay, Kevin; Connors, Joseph M; Sehn, Laurie H; Savage, Kerry J; Shenkier, Tamara; Klasa, Richard; Gerrie, Alina; Villa, Diego

2014-03-01

We examined the relationship between location of residence at the time of diagnosis of diffuse large B-cell lymphoma (DLBCL) and health outcomes in a geographically large Canadian province with publicly funded, universally available medical care. The British Columbia Cancer Registry was used to identify all patients 18-80 years of age diagnosed with DLBCL between January 2003 and December 2008. Home and treatment center postal codes were used to determine urban versus rural status and driving distance to access treatment. We identified 1,357 patients. The median age was 64 years (range: 18-80 years), 59% were male, 50% were stage III/IV, 84% received chemotherapy with curative intent, and 32% received radiotherapy. There were 186 (14%) who resided in rural areas, 141 (10%) in small urban areas, 183 (14%) in medium urban areas, and 847 (62%) in large urban areas. Patient and treatment characteristics were similar regardless of location. Five-year overall survival (OS) was 62% for patients in rural areas, 44% in small urban areas, 53% in medium urban areas, and 60% in large urban areas (p = .018). In multivariate analysis, there was no difference in OS between rural and large urban area patients (hazard ratio [HR]: 1.0; 95% confidence interval [CI]: 0.7-1.4), although patients in small urban areas (HR: 1.4; 95% CI: 1.0-2.0) and medium urban areas (HR: 1.4; 95% CI: 1.0-1.9) had worse OS than those in large urban areas. Place of residence at diagnosis is associated with survival of patients with DLBCL in British Columbia, Canada. Rural patients have similar survival to those in large urban areas, whereas patients living in small and medium urban areas experience worse outcomes.