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1.
This intervention contributes to recent work in urban geography that integrates the conceptual frameworks of assemblages and actor-network theory by highlighting two additional directions that require a more rigorous and detailed theorization. The first direction concerns the relationship between contingency and necessity in urban assemblages and actor-networks and this paper delineates four specific propositions as a starting point for further reflection. The second direction suggests that urban assemblages and actor-networks require a more explicit vocabulary for thinking about competition and cooperation within and between cities. To this end, the paper introduces a new concept – delayed asymmetric counterforces – that can foster a better understanding of competition-induced urban change and destabilization. The novel concept is developed in conjunction with a typology of delays in competitive urban dynamics, which helps illuminate how delayed asymmetric counterforces are both a cause and an effect of the complexity inherent in the urban realm.  相似文献   

2.
Sarah Launius 《Urban geography》2013,34(9):1335-1355
The financialization of urban development occurs even under conditions of credit constraint. The paper demonstrates that credit scarcity is an important and under-examined driver of policy improvisation and institutional development. Using the case of Tucson, Arizona, we show that local and extra-local interests overlap and cross-pollinate to produce unique hybrids – geographically specific and contingent institutional forms cultivated by local growth machines to attract outside financial interests. These dynamics are illustrated with a sales-tax-based tax increment financing district that employs “enhanced financings” to attract extra-local sources of debt and equity. We find that the financialization of urban development in the credit-constrained city is not just a process of abstraction, but also of particularization in which extra-local dollars flow through embedded local networks. We conclude with a call for greater attention to the intersections of finance and urban life in “ordinary cities”.  相似文献   

3.
Can a sense of ownership over constantly changing urban places be generated through pedestrian exploration and everyday digital media practice? This paper begins with the author’s visit to the city of Adelaide, where a chance encounter – an intriguing sign painted on the wall of a city building – led to a hunt through the city for ghost signs, the remnants of old hand-painted advertisements. This spontaneous activity, combined with the online exploration and image sharing that followed, generated a renewed feeling of connection to, and ownership over, an erstwhile familiar locale. The experience is analysed through the work of theorists investigating change and belonging in modern cities including Guy Debord, Doreen Massey, Michel de Certeau, Andreas Huyssen, and Mark Crinson, as well as the contemporary growth in both politically inspired urban exploring (“Urbex” or “place hacking”) and the digital documentation and sharing of ghost signs and other urban ephemera.  相似文献   

4.
The availability of spatial data on an unprecedented scale as well as advancements in analytical and visualization techniques gives researchers the opportunity to study complex problems over large urban and regional areas. Nevertheless, few individual data sets exist that provide both the requisite spatial and/or temporal observational frequency to truly facilitate detailed investigations. Some data are collected frequently over time but only at a few geographic locations (e.g., weather stations). Similarly, other data are collected with a high level of spatial resolution but not at regular or frequent time intervals (e.g., satellite data). The purpose of this article is to present an interpolation approach that leverages the relative temporal richness of one data set with the relative spatial richness of another to fill in the gaps. Because different interpolation techniques are more appropriate than others for specific types of data, we propose a space–time interpolation approach whereby two interpolation methods – one for the temporal and one for the spatial dimension – are used in tandem to increase the accuracy results.

We call our ensemble approach the space–time interpolation environment (STIE). The primary steps within this environment include a spatial interpolation processor, a temporal interpolation processor, and a calibration processor, which enforces phenomenon-related behavioral constraints. The specific interpolation techniques used within the STIE can be chosen on the basis of suitability for the data and application at hand. In this article, we first describe STIE conceptually including the data input requirements, output structure, details of the primary steps, and the mechanism for coordinating the data within those steps. We then describe a case study focusing on urban land cover in Phoenix, Arizona, using our working implementation. Our empirical results show that our approach increased the accuracy for estimating urban land cover better than a single interpolation technique.  相似文献   

5.
To date, little is known about the extent to which the creation of municipal green spaces over an entire city addresses social or racial inequalities in the distribution of environmental amenities – or whether such an agenda creates contributes to green gentrification. In this study, we evaluate the effects of creating 18 green spaces in socially vulnerable neighborhoods of Barcelona during the 1990s and early 2000s. We examined the evolution over time of six socio-demographic gentrification indicators in the areas close to green spaces in comparison with the entire districts. Our results indicate that new parks in the old town and formerly industrialized neighborhoods seem to have experienced green gentrification. In contrast, most economically depressed areas and working-class neighborhoods with less desirable housing stock and more isolated from the city center gained vulnerable residents as they became greener, indicating a possible redistribution and greater concentration of vulnerable residents through the city.  相似文献   

6.
This paper shows how regimes of spatial ordering in Brazil are produced by the entangling of neoliberalism, leftist populism and modernist visions. The paper focuses on Prometrópole, a slum upgrading project in Recife funded by the World Bank, which commenced in 2007. In this project, the neoliberal dimension manifests in the idea that the state, private companies and citizens together are responsible for (re)constructing urban space, and further, that beneficiaries should behave as autonomous citizens, taking responsibility for their new living environment. The leftist political dimension is seen in participatory procedures to involve the target population from project design through to implementation, in expectation of their cooperation with the government. The modernist aesthetics – of straight lines, open spaces and visible order – informs the project design with the requirement to use the new houses and public spaces according to the standards of ‘modern civilization’. As our research shows, such a regime of spatial ordering clashes with the livelihoods of the urban poor, whose quality of life might even deteriorate as a result of the intervention. Furthermore, so‐called participatory procedures fail to grant the target population any real influence in creating their environment. Consequently, these residents of the new housing estate drastically reconstruct their private and public areas, reappropriating the urban space and contesting the regime of spatial ordering imposed upon them.  相似文献   

7.
Urban development charges (UDC) are considered relevant taxation instruments that can improve the economic sustainability of urban areas and the financial health of the respective local governments. The economic formulation and justification based on the ‘direct benefit principle,’ the ‘accountability principle,’ and the ‘proportionality principle’ requires a methodology that can be supported by a geographic information system (GIS) application. This article presents the research output of a real case study – the municipality of Aljezur, Portugal – and the fundamentals of the GIS tool that was designed. This GIS-based methodology comprises a multi-annual infrastructure capital plan and an accurate zoning map for spatial differentiation of values combining municipal-wide and site-specific approaches, following ‘pay as the urban areas grow’ perspective applied to urban development and new buildings. It requires data integration of the urban planning process with infrastructure and urban growth data in order to manage and monitor the computation of this charge over time, thereby increasing the accuracy, the objectivity and the clarity of the process. The results obtained show that this UDC-GIS application seems well adapted to small municipalities. Its possible replication and use in other contexts require adaptations derived from different urban and taxation policy options and from different legal, organizational, technological, and informational local systems.  相似文献   

8.
We develop the relational economic geographical potential of the incubator and hinge functions of megalopolis incorporating ideas from the literature on regional innovation systems and New Argonaut connections respectively. Empirically, we investigate how China’s Yangtze River Delta (YRD) has incubated but also articulated knowledge interactions at different geographical scales. Drawing upon co-patent data from the World Intellectual Property Organization database, we show that the YRD’s knowledge hinge role has strengthened over time, notably as a result of the role played by economic entities in Shanghai – the YRD’s gateway city. To unpack the YRD’s knowledge hinge role, we use information attached to co-patents to distinguish different channels – multinational enterprises, Chinese domestic enterprises, universities and research institutes, and “New Argonaut” linkages – by which YRD cities have accessed exogenous knowledge at different geographical scales. In conclusion we highlight the value of megalopolis as a meso-scale unit of analysis for relational economic geography.  相似文献   

9.
Land use information over large areas is increasingly important for many studies related to environment in general and global change in particular. Yet there is a dearth of methodological knowledge in this area, especially regarding the practical task of producing land use maps. In this article, a systematic land use mapping approach is developed, based on land cover maps that in turn are produced through remote sensing. The concept is based on the recognition of varying strengths of land cover (LC) – land use (LU) relationships, from the thematic and spatial points of view. Several categories of relationships are identified, ranging from direct (case 1) to multiple/complex (case 4), and appropriate mapping strategies are discussed for these cases. Using a mapping study in Lebanon, it is shown that the principles embodied in this approach correspond to issues and conditions in real mapping situations. Finally, the concepts are translated into a series of steps through which the method can be applied to large areas, taking into consideration the specific requirements and constraints of each case. The final land use map represents an acceptable compromise between accuracy, level of detail, and cost.  相似文献   

10.
Land use information over large areas is increasingly important for many studies related to environment in general and global change in particular. Yet there is a dearth of methodological knowledge in this area, especially regarding the practical task of producing land use maps. In this article, a systematic land use mapping approach is developed, based on land cover maps that in turn are produced through remote sensing. The concept is based on the recognition of varying strengths of land cover (LC) – land use (LU) relationships, from the thematic and spatial points of view. Several categories of relationships are identified, ranging from direct (case 1) to multiple/complex (case 4), and appropriate mapping strategies are discussed for these cases. Using a mapping study in Lebanon, it is shown that the principles embodied in this approach correspond to issues and conditions in real mapping situations. Finally, the concepts are translated into a series of steps through which the method can be applied to large areas, taking into consideration the specific requirements and constraints of each case. The final land use map represents an acceptable compromise between accuracy, level of detail, and cost.  相似文献   

11.
The mechanisms and the specific character of flow-channel interaction and sediment transport that constitute the essence of river channel processes, vary over a wide range according to the flow rate of the rivers, their water regime, flow kinematics, the value of longitudinal gradient, and to the grain size and runoff of riverbed-forming sediments. Furthermore, the longitudinal gradient of a river is as important an energy characteristic as is the water flow rate, coupled with it, determines the capacity and character of a stream. Therefore the hydrological regime, varying over a wide range according to the longitudinal gradient, produces a variety of transport conditions for riverbed-forming sediments and – through them – the form of manifestation of channel processes.  相似文献   

12.
Michael Gentile 《Urban geography》2013,34(10):1455-1464
ABSTRACT

Despite the recent planetary turn that has swept through gentrification research, the theoretical barycentre remains pegged to a few strongholds located in the global north-west. Against this background, this essay offers a provincialized account of three gentrification-like trends – tele-urbanization, Schengtrification and colour-splashing – which are currently taking place in Tbilisi, Riga and Kiev. It is proposed that these processes are supported by an underlying logic that is not pinned to these cities’ specific (“post-communist”) contexts, raising questions about the avowedly universal validity of theories of gentrification stemming from the global northwest, and particularly those developed within the more critical scholarly tradition.  相似文献   

13.
One aspect of a recent restructuring of urban economies, societies, and spaces has been a change in urban planning practice. Planning is increasingly privatized and decentralized in U.S. cities. Private planning consultants are often hired by public‐private coalitions in order to shape the future of cities, while the planning processes they institute are frequently claimed to be consensus‐based, collaborative, and inclusionary, rather than elite‐centered and expert‐driven. This paper discusses the use of “visioning”—an increasingly popular technique that develops goals for the future of a city through consensus‐based meetings, open to all parties—as developed by New Century Lexington, a public‐private planning initiative in Lexington, Kentucky. It argues that: (1) new public‐private planning procedures, incorporating collaborative techniques, frequently become the institutional sites of political struggle over how future urban geographies are produced; (2) in order to understand the role of visioning in contemporary urban politics and in policy making outcomes, we must recognize the sociospatial context in which it is deployed; and (3) in the case of New Century, the way in which local elites controlled the mechanics of the visioning process made dissent difficult and, therefore, produced a vision of the future largely parallel to their standard economic development models.  相似文献   

14.
Data collected on rainfall events covering one wet season in Ilorin, Kwara State, Nigeria, were found to be highly correlated with the rate of erosion on all the representative land surface types found in the city – namely bare land, fallow land, short grass and tall tree cover. Of all the rainfall components, rainfall total was best at predicting the rate of soil erosion on all these surfaces. In addition, the study found that a significant constituent of all surfaces, silt which fell through seiver grades 1.18 mm did not cohere, therefore increasing the rate of erosion. However, when grass cover (regenerating with the rains) was at least 95 per cent, erosion was well controlled. Therefore, grass coverage before the onset of the wet season is recommended as an efficient and simple measure to manage erosion in this typical developing urban centre in Nigeria.  相似文献   

15.
Urbanization is an important issue concerning diverse scientific and policy communities. Computational models quantifying locations and quantities of urban growth offer numerous environmental and socioeconomic benefits. Traditional urban growth models are based on a single-algorithm fitting procedure and thus restricted on their ability to capture spatial heterogeneity. Accordingly, a GIS-based modeling framework titled multi-network urbanization (MuNU) model is developed that integrates multiple neural networks. The MuNU model enables a filtering approach where input data patterns are automatically reallocated into appropriate neural networks with targeted accuracies. We hypothesize that observations classified by individual neural networks share greater homogeneity, and thus modeling accuracy will increase with the integration of multiple targeted algorithms. Land use and land cover data sets of two time snapshots (1977 and 1997) covering the Denver Metropolitan Area are used for model training and validation. Compared to a single-step algorithm – either a stepwise logistic regression or a single neural network – several improvements are evident in the visual output of the MuNU model. Statistical validations further quantify the superiority of the MuNU model and support our hypothesis of effective incorporation of spatial heterogeneity.  相似文献   

16.
Climate and land-use changes are projected to threaten biodiversity over this century. However, few studies have considered the spatial and temporal overlap of these threats to evaluate how ongoing land-use change could affect species ranges projected to shift outside conservation areas. We evaluated climate change and urban development effects on vegetation distribution in the Southwest ecoregion, California Floristic Province, USA. We also evaluated how well a conservation network protects suitable habitat for rare plant species under these change projections and identified primary sources of uncertainty. We used consensus-based maps from three species distribution models (SDMs) to project current and future suitable habitat for 19 species representing different functional types (defined by fire-response – obligate seeders, resprouting shrubs – and life forms – herbs, subshrubs), and range sizes (large/common, small/rare). We used one spatially explicit urban growth projection; two climate models, emission scenarios, and probability thresholds applied to SDMs; and high-resolution (90 m) environmental data. We projected that suitable habitat could disappear for 4 species and decrease for 15 by 2080. Averaged centroids of suitable habitat (all species) were projected to shift tens (up to hundreds) of kilometers. Herbs showed a small-projected response to climate change, while obligate seeders could suffer the greatest losses. Several rare species could lose suitable habitat inside conservation areas while increasing area outside. We concluded that (i) climate change is more important than urban development for vegetation habitat loss in this ecoregion through 2080 due to diminishing amounts of undeveloped private land in this region; (ii) the existing conservation plan, while extensive, may be inadequate to protect plant diversity under projected patterns of climate change and urban development, (iii) regional assessments of the dynamics of the drivers of biodiversity change based on high-resolution environmental data and consensus predictive mapping, such as this study, are necessary to identify the species expected to be the most vulnerable and to meaningfully inform regional-scale conservation.  相似文献   

17.
《Urban geography》2013,34(5):361-385
Defining the concept of neighborhood has long been a goal in urban research. In this paper, I trace the various meanings of neighborhood articulated by scholars, from neighborhood-as-community to functional and demographic typologies, to examinations of the effects of residential environments on human behavior. In identifying the myriad meanings of neighborhood, this paper highlights the contingency and flexibility of the concept. I argue that it is precisely because of its blurriness and flexibility that neighborhood has salience: The concept of neighborhood is primarily a social and political product, created through activism, and through research on sociospatial relations. Rather than seeking a fixed definition that can apply to many circumstances, I argue that research on neighborhoods ought to focus on how neighborhoods are produced socially and, in turn, physically, through cooperation and conflict. I apply this framework of enacting neighborhood to a brief case study of neighborhood conflicts in Athens, Georgia.  相似文献   

18.
This paper aims to qualify the behaviour of contributors to OpenStreetMap (OSM), a volunteered geographic information (VGI) project, through a multigraph approach. The main purpose is to reproduce contributor’s interactions in a more comprehensive way. First, we define a multigraph that combines existing spatial collaboration networks from the literature with new graphs that illustrate collaboration based on specific aspects of the VGI modes of contribution through semantics, geometry and topology. Indeed, the ways that contributors interact with one another through editing, completion, or even consumption may provide additional information on each user’s operation mode and therefore, on the quality of the contributed data. Social collaborations drawn from indirect criteria – for example, comparisons between contributors’ activity areas – can also be contemplated under another network. Second, the resulting multigraph is analysed using data mining approaches to characterise individuals and identify behavioural groups. The implementation of a multiplex network based on an OSM data sample and an initial analysis make it possible to identify useful behaviours for data qualification. The initial results characterise some contributors as pioneers, moderators and truthful contributors, according to their special roles in the graphs. Mapping elements that include these contributors’ participation are likely to be reliable data  相似文献   

19.
Miguel Kanai 《Urban geography》2013,34(8):1111-1117
In this paper, I problematize the connections between global tourism, urban redevelopment and cultural policy in Buenos Aires. Market-oriented approaches to urban growth have continued after Argentina’s economic collapse of 2001–2002. Devaluation produced unprecedented international affordability, which triggered a tourism boom. City government capitalized on this through cultural initiatives. Yet tourist-oriented cultural entrepreneurialism promoted forms of disjointed redevelopment that exacerbate socio-spatial inequality and fragmentation. Moreover, Mayor Macri has been advancing a cultural politics of scale that recasts Buenos Aires as a world-class city, while mobilizing localist identities to oppose national efforts towards income redistribution and intercultural recognition. Particularly important have been the recent appropriations of tango as a cultural commodity. Deployed for city marketing and selective reinvestment, tango also emboldens Eurocentric narratives of cosmopolitan urbanity that legitimize racialized exclusion and geographical elitism. Concluding remarks suggest that socio-political uses of tango are not the exclusive domain of neoliberal urbanism, and research implications are discussed beyond Buenos Aires.  相似文献   

20.
From Shanghai's Pudong to Dubai's Marina, waterfront developments are increasingly popular urban forms worldwide. Drawing on the literature on urban assemblages, I explore how urban waterfronts are produced out of the transnational assembling of models, knowledge and expertise. My case study here is Marina Bay, Singapore, a landscape that like much of the rest of Singapore is a product of talent and ideas from elsewhere. In this paper, two strategies employed by Singapore's urban authorities to court global expertise for Marina Bay's development are examined – their formation of an international panel of experts in the fields of urban planning, policy and design, and their launching of international competitions to attract top design firms. Like transfer agents that enable policies to travel, I argue that these individuals and firms are situated within wider knowledge circuits that straddle the globe, and are thus well placed to filter and channel ideas from elsewhere to Singapore. Drawing on selected developments within Marina Bay, I trace the routes taken by these ideas, the changes they underwent as they travelled, as well as their relationships with the actors that facilitated their journeys. In doing so, I hope to demonstrate the usefulness of understanding the urban as more‐than‐territorial in both theory and practice.  相似文献   

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