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31.
This article contributes to a small but growing body of multi-sited and multi-scalar research on the Belt and Road Initiative.We focus on relations at the national,regional and international scales,and present original research from China and Turkey,to show how the Istanbul-Ankara high-speed railway has served as a testing ground for China's Belt and Road Initiative(BRI).Its construction was initially funded by the European Investment Bank,but it is now part of the backbone of the Turkish Government's Middle Corridor plan which enhances west-east connectivity and integration with the Caucasus and Central Asia.We show that in contrast to multinational corporations from the OECD that seek to remain footloose,Chinese state-owned enterprises(SOEs)seek to adapt to,apprehend and ultimately shape local in-stitutions.In the case of Turkey this proved difficult given its institutional alignment with the European Union.Thus,while the railway project was completed successfully by a consortium led by a Chinese SOE,Turkey's dynamic and complex regulatory environment discourages Chinese SOEs in the infrastructure sector.We conclude that the Turkish and Chinese gov-ernments are currently pursuing complementary territorial visions yet their cooperation is project-based and pragmatic.  相似文献   
32.
Research on place attachments and identities has made an important contribution to understanding social acceptance of low carbon infrastructure, which are often objected to by local communities. However, a focus on local attachments predominates in studies to date, neglecting the potential role of national and global attachments and identities on energy beliefs and attitudes, despite the fact that large energy infrastructures are not only local in significance or function. To investigate this, survey data was collected from a representative sample of UK adults (N = 1519), capturing place attachments at local, national and global levels, climate change concern, beliefs about power lines and support for energy system change. Findings show significant differences in infrastructure beliefs and attitudes depending upon relative strength of attachments at different levels, controlling for personal characteristics. Analyses of variance revealed that individuals with stronger national than local or global attachments were less likely to support European grid integration; those with relatively stronger global attachment were most likely to support decentralised energy and those with relatively stronger local attachment were most likely to protest against a nearby power line. In addition, those with strong attachments at local, national and global levels were most willing to reduce energy demand, and those with weak attachments were least likely to trust grid companies. Relatively stronger global than national attachment was positively associated with support for decentralised energy, with this effect partially mediated by climate change concern. Explanations for the findings and implications for future research are discussed.  相似文献   
33.
A wide-ranging set of physical, urban, demographic, socioeconomic, and policy characteristics determines the spatial distribution of urban forests. Information on the characteristics surrounding tree removals on both public and private properties has received less attention in the literature. The purpose of this research was to analyze the spatiotemporal trends and geographic patterns of tree removals in Austin, Texas, between 2002 and 2011 in an effort to understand how site-specific characteristics influence urban tree removal and affect the overall distribution of Austin's urban forest. We examined permitted tree removals using a geographic information system (GIS) as well as spatial and statistical analyses. Specifically, we evaluated the degree to which variables related to various physical, urban, and socioeconomic conditions predicted tree removals. The results indicate that permitted tree removals and their associated characteristics in Austin have varied over the ten-year study period. Permitted tree removals increased over the study period and took place in the urban core and along the urban periphery. Permitted tree removals were more likely to be undertaken by college graduates and owner-occupants and to occur in more densely populated areas, closer to major streets, and on properties with older structures. The results of this research provide urban forest professionals with information on the location and intensity of permitted tree removals and the significant characteristics driving urban tree loss.  相似文献   
34.
Though relationships between urbanization and tree cover are generally well studied, the effect of redevelopment on urban trees, at the scale of the individual property, is not well understood. Developing knowledge in this area is important in order to limit tree loss during redevelopment and thus, ensure sustained ecosystem services. Here, we explore the removal or retention of trees adjacent to building demolition in Christchurch, New Zealand. We mapped the presence or absence of individual trees on 123 properties prior to, and following, building demolition. Using a classification tree (CT) analysis, the presence or absence of 1209 trees was modelled as a function of: tree-related variables, property-related variables, and economic variables. The CT model estimated tree presence/absence with overall accuracy of 80.4%. Results show that 21.6% of all trees were removed as a consequence of building demolition, resulting in a tree canopy cover reduction of 19.7% across all 123 properties. The CT showed that tree crown area was the most important variable for predicting the presence/absence of trees, whereby trees with small crown areas (<7.9 m2) were most frequently removed, especially if they were within 0.7 m of a demolished building. Land value was also an important determinant of tree presence/absence, such that tree removal was more prevalent on properties with higher land value ($/m2). The results provide important new insights into some of the reasons for tree removal or retention during redevelopment at the scale of the individual property where most tree-related decisions are made.  相似文献   
35.
Green infrastructure has recently risen to international prominence for its purported capacity to enhance urban sustainability, and particularly to modulate ambient temperatures in the context of climate change. We assess whether residents in a sub-tropical Australian city perceive green infrastructure as an effective climate adaptation response for reducing vulnerability to heat stress. Gold Coast City has pursued urban densification policies, such as reducing block sizes and increasing building heights, to accommodate rapid population growth. Little attention has been given to the combined impact of local heat island effects and global climate change upon lower-income residents in the city's suburban fringe, including rising energy costs associated with cooling homes. The study has three aims: to assess whether social disadvantage is associated with (1) concern about climate change impacts; (2) perceptions about the potential of green infrastructure to offer potential climate-adaptive benefits; and (3) the desire for more urban greening in a working class suburb. We used a mail-back survey to elicit information related to cooling dwellings, awareness of, and concern about, climate change impacts, perceptions of the benefits of green infrastructure, and desire for more urban greening. Results indicate that despite their vulnerability to heat stress, comparatively disadvantaged residents are no more concerned about climate change; nor are they any more inclined to encourage local government to enhance neighbourhood greenery. These residents are, if anything, less likely to perceive benefits of urban greening. Our findings indicate that cultivating support for green infrastructure in disadvantaged neighbourhoods will require parallel efforts to redress inequality.  相似文献   
36.
Comparison is now taken as vital to the constitution of knowledge about cities and urbanism. However, debate on comparative urbanism has been far more attentive to the merits of comparisons between cities than it has been to the potential and challenges of comparisons within cities—to what we call “Intra-Urban Comparison” (IUC). We argue that a focus on the diverse forms of urbanism located within cities may generate critical knowledge for both intra- and inter-urban comparative projects. IUCs highlight the diversity inherent in the category “city,” revealing dimensions of the urban that are central to how cities work and are experienced. We mobilise fieldwork within three cities: Mumbai, Delhi and Cape Town, and consider both how these cities have been historically understood as different urban worlds within a city, and discuss key findings from IUCs we have conducted on infrastructures. We find that IUCs can enhance comparative work both within and between cities: reconceptualising urban politics; attending to the varied and contradictory trajectories of urban life; and bringing visibility to the diverse routes through which progressive change can occur.  相似文献   
37.
Jessie Speer 《Urban geography》2016,37(7):1049-1069
In 2013, Fresno, California was home to more than 5,000 homeless people, many of whom took refuge in sprawling downtown encampments. Citing unsanitary conditions, Fresno officials implemented a policy of bulldozing the encampments while providing housing vouchers to a small number of residents. Yet homeless Fresnans by and large demanded the provision of sanitation in the encampments as an alternative to eviction. In doing so, they invoked their right to urban infrastructure. Drawing from literature on informal housing in the Global South, this paper argues that individual housing rights present a limited framework through which to understand homeless people’s right to the city, and that a truly radical right to the city should reflect the demand for sanitation infrastructure emerging from the streets.  相似文献   
38.
Moringa oleifera (MO), also known as drumstick tree, has gained worldwide attention among researchers and policy makers, for showing its remarkable potential in environmental management. Recently, MO seed or press cake (a by-product of oil extraction industry) powder has also emerged as an alternative and promising coagulant for environmental remediation. In this view, attempts have been made in this study to evaluate the efficacy of MO seed and press cake powder (MSP & PCP) for the treatment of municipal wastewater. Both MSP and PCP are characterized by using swelling ratio, scanning and transmission electron microscopy analysis. The effect of various operational parameters such as coagulation–flocculation pH (2–10), coagulant dosage (0.1–1 g L−1), and sedimentation time (0–180 min), etc., is investigated to understand the potential of MSP and PCP. At optimized operational conditions, sedimentation kinetics is also performed suggesting that the treatment process is being governed by the second-order kinetic model. The chemical and biological oxygen demand removals at optimized conditions are observed as follows: ≈38 and ≈73% for MSP and ≈47 and ≈85% for PCP. Overall, the results of the present study elucidated that PCP can be employed as a promising alternative of MSP for municipal wastewater with improved treatment efficiencies.  相似文献   
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