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1.
The form of many Canadian cities has dramatically evolved over the past six decades due to urban sprawl. Several patterns can characterize this evolution including unlimited horizontal expansion of the city, leapfrog, and low‐density residential development at the outskirts, and widespread strip commercial and power centre retail development. Hamilton, Ontario is an example of a Canadian city that has experienced suburbanization and sprawled development for several decades. However, the nature of this sprawled development is unclear and its impact on urban form is not entirely understood. In this article, several hypotheses pertaining to sprawled land development and urban form are postulated and tested. The tests rely on point source data of the developed land parcels in Hamilton during the period 1950–2003. A number of spatial statistics techniques, including kernel estimation and complete spatial randomness (CSR) K‐function tests, are employed to examine the emerging nature of urban form. We hypothesize that while the city has been sprawling, the ongoing land development process is leading urban form into multinucleation. To support this assumption, we further hypothesize the existence of an interdependent spatial relationship between residential and commercial land uses at the emerging nuclei. Accordingly, we examine the strength of co‐clustering among these land use activities over time. The findings indicate that while the city has been sprawling, several consequent urban nuclei with mixed land use activities have been emerging and become more visible in recent years. This is an indication that the city's form is progressively becoming multinuclear. Furthermore, the estimates for the 1990s indicate interdependence between the locational patterns of residential and commercial land development. Co‐clustering between these two types of land uses is bi‐directional and occurs at a time lag of three to seven years. These findings affirm the existence of interdependence between land use activities at the observed nuclei, which support the emergence of a multinucleation.  相似文献   

2.
交通拥堵是制约国内外城市可持续发展的瓶颈问题之一,给城市经济、社会与环境带来诸多负面影响.本文聚焦城市交通拥堵的结构性因素,系统归纳和综述了引导可持续出行行为的空间政策(如城市空间结构和土地利用政策)与基础设施供应侧政策(如道路和公共交通基础设施投资政策),及其在交通拥堵治理上的理论探讨、学术争论焦点、实证分析及当前亟...  相似文献   

3.
U.S. post‐war suburbanization has reshaped the spatial pattern of growth in many metropolitan areas, with population and employment shift toward the suburbs resulting in the urban decay of central cities. This being the case, the adoption of adequate anti‐sprawl policies should lead to a reduction in city blight. Availability of detailed blight measures at the city level enables us to undertake a novel empirical analysis to test this hypothesis. The empirical specification presented here identifies the specific impact of more stringent anti‐sprawl policies adopted at the metro level, proxied by the adoption of urban containment policies, on city blight. Results indicate that the adoption of such policies has effectively contributed to the reduction of downtown deterioration.  相似文献   

4.
Based on a study in four Norwegian cities (Oslo, Stavanger/Sandnes, Bergen and Trondheim) differing in size and centre structure, this article illuminates how residential and workplace location, local-area density and transit accessibility influence different aspects of travel behaviour. We find strong effects of residential and workplace distance to the city centre on overall driving distances and commuting distances. We also find clear effects of local area densities around residences and workplaces on the choice of car as a travel mode, along with less pronounced effects of the distance from dwellings and workplaces to the city centre. In the cities with the best developed transit provision, we also see clear effects of transit accessibility at the residence on the propensity of choosing the car as travel mode. The results provide strong support of Norwegian national policies of urban densification as a planning strategy to curb the growth in urban motoring. However, although the influences of urban structure on travel show many similarities across the four cities, there are also important differences reflecting variations in centre structure (predominantly mono- or polycentric) and population size. The magnitude of the influences of various urban structural characteristics on travel behaviour are thus highly context-dependent.  相似文献   

5.
ABSTRACT This paper suggests a cause of low density urban development or urban sprawl that has not been given much attention in the literature. There have been a number of arguments put forward for market failures that may account for urban sprawl, including incomplete pricing of infrastructure, environmental externalities, and unpriced congestion. The problem analyzed here is that urban growth creates benefits for an entire urban area, but the costs of growth are borne by individual neighborhoods. An externality problem arises because existing residents perceive the costs associated with the new residents locating in their neighborhoods, but not the full benefits of new entrants which accrue to the city as a whole. The result is that existing residents have an incentive to block new residents to their neighborhoods, resulting in cities that are less dense than is optimal, or too spread out. The paper models several different types of urban growth, and examines the optimal and local choice outcomes under each type. In the first model, population growth is endogenous and the physical limits of the city are fixed. The second model examines the case in which population growth in the region is given, but the city boundary is allowed to vary. We show that in both cases the city will tend to be larger and less dense than is optimal. In each, we examine the sensitivity of the model to the number of neighborhoods and to the size of infrastructure and transportation costs. Finally, we examine optimal subsidies and see how they compare to current policies such as impact fees on new development.  相似文献   

6.
ABSTRACT This paper documents the long‐run trends in the average densities and density gradients of urban areas in the United States. The data show that between 1890 and 2000 the average densities of cities and metropolitan areas rose and fell but that the density gradients of urban areas generally declined monotonically over time. While it is beyond the scope of this paper to estimate the causes of these changes, this paper argues that a complete understanding of the changes in the nature of US urban spatial structures is likely to go beyond the standard explanations based on the monocentric city model such as decreases in transportation costs and increases in household incomes.  相似文献   

7.
ABSTRACT We develop a duocentric‐city model and show that the ratio between the property tax in the suburbs and in the center has an ambiguous impact on the size of the city. We test this model by using a dataset of effective property tax rates which we developed using GIS techniques for central cities and suburbs in 445 urbanized areas. Results from the empirical analyses suggest that a lower property tax rate in the suburbs as compared to the central city is associated with more expansive urban growth and a greater level of decentralization of population and employment.  相似文献   

8.
Recent studies on urban poverty in Canadian cities suggest a growing spatial concentration of poor populations within metropolitan regions. This article assesses trends in the intra‐urban distribution of the poor population from 1986 to 2006 in eight of Canada's largest cities. We consider five well‐known dimensions of segregation, as identified by Massey and Denton (1988) , in order to examine changes in the spatial distribution of poor populations within metropolitan areas: evenness, exposure, concentration, clustering, and centralization. These indices were calculated for low‐income populations at the census tract level using data from five Canadian censuses. Although each metropolitan area has distinctive characteristics, we were able to identify some general trends. The results suggest that, in 2006 compared to 1986, low‐income populations lived in more spatially concentrated areas, which were, at the same time, socioeconomically more homogeneous and more dispersed throughout the metropolitan area. In addition, we observed that over the last twenty years areas of poverty have been located, for the most part, in neighbourhoods adjacent to downtown cores. Nevertheless, we found that poverty has mostly increased in suburban areas located outside inner‐city neighbourhoods. Growing socioeconomic homogeneity and dispersion of low income areas in metropolitan areas reveal new spatial patterns of urban poverty distribution. These findings should be cause for concern as social isolation in the most disadvantaged neighbourhoods could affect the life chances and opportunities for the residents of those areas.  相似文献   

9.
Starting from an econometric model of local employment growth, applied to Canada (1971–2001), residuals—relative to model predictions—are analyzed over time and over space, in turn allowing us to draw a distinction between general explanatory variables and factors of a more local, cyclical or accidental nature. The model's explanatory power grows over time, founded on variables such as urban size, market access and industrial structure, allowing us to conclude that local employment growth in Canada follows an increasingly geographically predictable pattern. However, an examination of the residuals reveals more localized processes. Growth volatility is most manifest in Alberta and British Columbia, home to the most erratic local economies. Emerging patterns are visible in the last period, most notably the underperformance of Northern Ontario and of non‐metropolitan communities between Windsor and Québec City, lying along the Great Lakes and the Saint Lawrence. The over‐performance—compared to model predictions — of small and mid‐sized towns in south‐eastern Québec can, on the other hand, be interpreted as a sign of truly local social processes, generally associated with a particularly dynamic local entrepreneurial class.  相似文献   

10.
Although the “food desert” concept has captured the public imagination and spurred public policy efforts in many North American cities, the term has been critiqued by academics for being definitionally and methodologically vague, and for providing an incomplete picture of the complexity of food access. Rather than dismiss the study of urban, inner‐city food deserts, however, scholars can study disparities in retail food access through a historical, critical political economy lens to understand underserved retail landscapes as a product of capital formation and rescaling over time. The purpose of this article is to conduct such an analysis, using the case study of a low‐income community in Kingston, Ontario. Using historical research and qualitative interviews, the major finding of this analysis is that the physical accessibility of retail food appears to have declined over time in relation to the capitalization of the retail food sector. An imperfect relationship can be outlined over three phases of Canadian urban economic history to suggest that the food desert problem emerged largely in the transition from a decentralized, small‐scale, and neighbourhood‐embedded retail food industry to the scaled‐up, disembedded industry that now dominates the landscape. This industry‐level rescaling is contributing to a new urban politics of class and consumption through subtle, everyday activities such as food shopping.  相似文献   

11.
We propose an urban search‐matching model with land development. Wages, unemployment, prices of housing and land are endogenously determined. We characterize the steady‐state equilibrium and then discuss the issue of efficiency. To explore interactions among markets, we implement comparative static analysis. We also consider three policies: an entry‐cost policy that reduces firms' entry, a transportation policy that reduces commuting costs, and a housing policy that decreases rental prices. We find that the transportation and housing policies are more efficient if the unemployment rate is low, while the entry‐cost policy is more efficient if the unemployment rate is high.  相似文献   

12.
Indigenous families are overrepresented among those within Canada who experience food insecurity. Studies have largely focused on northern populations, with less attention paid to southern and urban communities, including the social, cultural, and geographic processes that challenge food security. In this study, we present findings from a decade‐long community‐based study with the Southwest Ontario Aboriginal Health Access Centre (London, Ontario) to examine family perspectives related to the social determinants of food security. These topics were explored through qualitative interviews (n = 25) and focus groups (n = 2) with First Nation mothers with young children from the city of London, and a nearby reserve community. Interviewees from both geographies identified a number of socio‐economic challenges including household income and transportation. However, some interviewees also shed light on barriers to healthy eating unique to these Indigenous contexts including access issues such as a lack of grocery stores on‐reserve; loss of knowledge related to the utilization of traditional foods; and the erosion of community, familial, and social supports. Resolving these unique determinants of food security for urban and reserve‐based First Nation families will require a range of economic and culturally specific interventions, particularly those that support development and uptake of Indigenous foodways.  相似文献   

13.
High-occupancy vehicle (HOV) lanes have been promoted to encourage carpools, reduce traffic congestion, and improve air quality. At the partial equilibrium level, commuting with three workers per automobile clearly reduces highway congestion, lowers carbon emissions, and saves energy compared with three single drivers. This paper develops a numerical urban simulation model to generate the general equilibrium effects of HOV lanes on urban spatial structure, energy use, and greenhouse gas emissions. The major findings are that while HOV lanes reduce traffic congestion and improve welfare, the fall in transportation cost leads to urban sprawl, which results in higher dwelling energy use and a larger carbon footprint. Overall, the HOV lane policy has little effect on total energy consumption and carbon emissions. This is another classic case of general equilibrium effects reversing the partial equilibrium effects of an urban policy. In contrast, a gasoline tax policy leads to less urban sprawl but is less effective at lowering energy consumption and carbon emissions. Imposing congestion tolls is a more effective tool at reducing traffic congestion, saving energy, and lowering carbon emissions.  相似文献   

14.
Abstract. In an attempt to slow the consumption of urban land for a given population, and the negative outcomes thought by some to be generated by such sprawl, regulations in the form of (i) the local imposition of urban containment policies that restrict or prohibit the amount and/or the type of urban settlement beyond a certain line and (ii) the statewide enactment of mandatory growth management requirements for all local governments have been enacted in the United States. This paper describes a regression‐based analysis that finds that different forms of these policies are achieving their desired goal of shrinking the square mile size of an urban area. A comparison of the influence of the various forms of urban containment and growth management policies with other “natural evolution,”“flight from blight,” and “fiscalization of land use” factors that also influence the square mile size of an urban area is made, and policy implications are offered.  相似文献   

15.
Research around the world has been nearly unanimous about the positive impacts of Indigenous‐led health organizations on Indigenous peoples' qualitative experiences in health care, in the face of often negative experiences in non‐Indigenous‐led health care settings. Urban environments, including health care environments, are areas of increasing attention with regard to Indigenous peoples' health in Canada. In this study, which took place in the northern city of Prince George, British Columbia, 65 Indigenous community members and health services workers participated in interviews and focus groups, describing their experiences with urban Indigenous‐led health organizations—defined in this study as non‐governmental organizations that prioritize the values and practices of local Indigenous communities. Employing perspectives on place and relationships drawn from Indigenous critical theory and Indigenous community resurgence to analyze the findings of this qualitative study leads to a focus on how relationships impact and can even constitute places, enabling new understandings of the roles of Indigenous‐led health organizations in urban Indigenous community resurgence.  相似文献   

16.
This article argues that a new landscape of urbanization takes shape in Canadian cities. In‐between the old downtowns and the new suburbs of urban Canada, a hitherto underexposed and under‐researched mix of residential, commercial, industrial, educational, agricultural and ecologically protected areas and land uses has become the home and workplace, and increasingly also the playspace of most people in Canada. The article examines this new landscape through the lens of the specific risks and vulnerabilities experienced by its inhabitants and users. Using a propane gas explosion in Toronto in the summer of 2008 as an example, we demonstrate that the ‘in‐between city’ is a space of great complexity, which has grown haphazardly and in a contradictory fashion, where, in contrast to the archetype of inner city and suburb, no clear spatial imaginary has been guiding urban development. This leads to always uncomfortable and sometimes dangerous proximities between various and competing uses and social practices. This is nowhere as clear as it is in the splintered urban infrastructures that service this landscape or use the in‐between city's space to service other adjacent or distant purposes.  相似文献   

17.
This paper explores the concepts of old‐growth forests, preservation and natural disturbance and demonstrates how contemporary biogeographic theory contributes to successful preservation of old‐growth forests. The case study analyzes the composition, structure, age and growth histories of trees in Big Timber Park, Whistler, British Columbia. Composition. The structure of the forest was diverse and tree ages ranged from 122 to 305 years. The densities of large old Douglas‐fir, shade‐tolerant trees and all snags are indicative of old‐growth forests; however, maximum tree diameters and densities of large snags and logs do not meet quantitative criteria for old‐growth forests. The abundance of tree regeneration and understory vegetation are relatively low. We conclude that some aspects of Big Timber Park are transitional between the mature and old‐growth stages of forest development. In the future, fine‐scale canopy gaps caused by tree senescence and interactions among insects, pathogens and wind are expected to dominate stand dynamics. Forest structure will become increasingly complex, exemplifying the dynamic nature of old‐growth forests. To successfully preserve Big Timber Park and La préservation des forêts other old‐growth forests in Canada requires understanding of natural disturbances. Preservation and the criteria and indicators used to measure successful preservation must explicitly include elements of natural change.  相似文献   

18.
南通地处长江三角洲北隅的沿江沿海交界处,位于我国一级开发轴线"T"型的顶点,与上海隔江相望。南通市域城镇形成和空间结构演变是伴随着陆地的不断长成而自西北向东南推进,城镇数量由无到有,城镇空间结构由简单到复杂,城镇规模由小到大,城镇联系由松散至紧密。历史时期城镇的形成与发展可分为三阶段:城镇空白阶段,城镇形成阶段,中心城市出现阶段等。南通市域城镇的最初形成与煮盐业、水运及海防等因素密切相关,故城镇多沿海岸线呈不规则的弧形分布,沿运河均匀分布。中心城市通州形成后,挣脱了对扬州和泰州的依赖,在行政上与其并列,城镇多沿通州城分布。  相似文献   

19.
In a city there are hotspots that attract citizens, and most of the transportation arises when citizens move between their residence and primary destinations (i.e. hotspots). However, an ex ante evaluation of energy-efficient mobility and urban residential planning has seldom been conducted. Therefore, this paper proposes an ex ante evaluation method to quantify the impacts, in terms of CO2 emissions induced by intra-urban car mobility, of residential plans for various urban areas. The method is illustrated in a case study of a Swedish midsize city, which is presently preoccupied with urban planning of new residential areas in response to substantial population growth due to immigration. In general, CO2 emissions increase from the continued urban core area (CUCA), to the sub-polycentric area (SPA), to the edge urbanization area (EUA), where CO2 emission of EUA is twice that of the CUCA. The average travel distances also increase in the same pattern, though the relative increase is more than four times. Apartment buildings could be more effective in meeting residential needs and mitigating CO2 emissions than dispersed single-family houses.  相似文献   

20.
This paper examines the response by local government and stakeholders to the arrival and resettlement of Syrian newcomers in Hamilton, Ontario in 2015 and 2016—the first major wave of refugee arrivals since two significant changes in Hamilton's settlement organizational landscape. The creation of a local immigration partnership called the Hamilton Immigration Partnership Council (HIPC) is an example of place‐based policymaking within local immigration and settlement in Canada. Place‐based approaches emerged to bypass top‐down policy ineffectiveness, and the shift to empower civic participation in the local decision‐making process is seen as one solution to public policy innovations. Examination of HIPC's role in this context is thus critical to understand the challenges and learnings encountered in one place‐based setting. Our findings suggest that the lack of power (in terms of information, communication, resources, and funding) led to a missed opportunity for HIPC to lead a significant resettlement initiative. HIPC's inability to bring together key partners across the sector prior to and during the event is symptomatic of systemic barriers the Council had faced, including competing interpretations of HIPC and its role by its members. This study suggests the effectiveness of place‐based policy is not without its nuances, and iterative challenges and learnings.  相似文献   

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