An inventory of trees in Dublin city centre

While urban areas are often considered to be comprised chiefly of artificial surfaces, they can contain a substantial portion of green space and a great diversity of natural habitats. These spaces include public parks, private gardens and street trees, all of which can provide valuable environmental services, such as improved air quality. Trees play a particular role in cities as they are often placed along roadsides and in the median strip of busy streets. As such they regulate access to sunshine, restrict airflow, provide shelter, scavenge air pollutants and manage noise at the street level. A tree planting policy can be an important part of a broader environmental strategy aimed at improving the quality of life in urban areas but this requires up-to-date knowledge of the current tree stock, which does not exist for Dublin. This article presents an inventory of trees in Dublin's city centre, defined as the area between the Grand and Royal canals. The results show that there are over 10,000 trees in the study area representing a density of 684 trees km-2 or one tree to approximately every 50 residents of the city centre. The tree canopy extent when in full foliage was nearly 1 km2 in extent or 6% of the study area. A more detailed analysis of those trees planted along streets shows little species variation but clear distinction in the sizes of trees, which is indicative of the age of planting. These data are used to estimate the carbon stored in Dublin's trees.     

Spatial and social transformations in a secondary city: the role of mobility in Sekondi-Takoradi,Ghana

Abstract

Existing research on urban Ghana mainly focuses on processes occurring within the country’s major cities, thereby reproducing a trend within the social sciences to overlook the role of intermediate and secondary cities. This paper aims to address this shortcoming by exploring spatial and social transformations in Sekondi–Takoradi, one of Ghana’s secondary cities and the metropolitan area serving the region’s emerging rubber industries as well as the country’s oil and gas economy. Using qualitative interviews conducted with residents in five of the city’s neighbourhoods, and a modified version of Kaufmann’s typology of mobility, we examine migration into Sekondi–Takoradi, residential mobility within the city and the daily mobility of the city’s residents. The paper highlights how these diverse forms of mobility interact with processes taking place both within and outside Sekondi–Takoradi, most notably influencing and being influenced by livelihood strategies. It is argued that the city and its hinterlands can best be envisaged as a mobile networked whole, rather than consisting of disconnected and compartmentalized locales. The paper thus contributes to broader debates on how mobility shapes urbanization by providing new empirical data on events unfolding in Africa’s secondary cities, and extends existing research by providing a counter-narrative to literature that examines the city and its surrounding rural areas separately.     

红树林造林技术

红树林在海岸防护方面的重要作用越来越受到人们的广泛关注,红树林的造林也掀起了新一轮的热潮。广东湛江是开展红树林造林比较早的地区,多年来积累形成一套自成体系的造林技术。     

民族旅游地区家空间的主客角色冲突研究——以丽江白沙村为例

以社会角色与角色冲突的相关理论为指导,以云南丽江白沙村当地纳西族居民家的微观空间为研究对象,对当地居民与游客在互动过程中的角色冲突质性进行了研究。研究发现,当地少数民族居民与汉族游客在家空间的互动过程中,双方各自存在角色内冲突的现象,同时彼此之间也存在两种角色间冲突现象。互动双方在处理这些角色冲突的过程中,既反映出当地居民对经济利益的诉求,也反映出当地居民与游客在家空间中的地位与权力关系。     

历史街区更新驱动下的旅游绅士化研究 ——以佛山岭南天地为例

综合采用质性和定量方法,从社会阶层、物质环境和消费方式等层面研究佛山岭南天地的旅游绅士化现象,并分析原住民在绅士化过程中的情感特征。结果发现,物质环境改造加速了地方社会阶层的更替,原住民大多被游客、中产阶级和房产投资者所替代,空间利用方式呈现出高度商业化特征。旅游绅士化虽有力地推动了地方的环境改造和经济发展,却衍生出阶层更替、社会排斥和空间隔离等副产品,使传统的本地化生活空间转变为“资本空间”与“消费空间”。城市历史街区改造不同于一般城市更新,街区更新应以地方性为落脚点,尊重原住民的情感与历史记忆,不应简单通过商业化手段推进历史街区更新。     

Urban landscape as mirror of ethnicity: trees of the South Plains

The literatures on urban forestry, environmental justice, and Marxist urban political ecology are considered through empirical attention to the localized racial and ethnic politics which spatially differentiate urban socio-natural landscapes. In the American Southwest, urban landscapes reflect a history in which Anglo Whites were able to distance themselves from spaces of production while gaining access to superior residences and environmental amenities in spaces of reproduction; ethnoracially marginalized Others were treated as necessary yet disfavored populations, thus constituting a segregated mode of production. In this study, we investigate the association between tree canopy cover and the location of urban ethnic minority populations with a focus on the arid Southern High Plains city of Lubbock, Texas. Using data from color infrared aerial photography and block-group demographic indicators from the 2010 US Census, we analyze the city’s arboreal landscape with a mix of methods—hierarchical regression, archival research, and field observation. Results confirm that a lack of tree cover in minority neighborhoods is a symptom of broader environmental inequalities in which contemporary segregation patterns reflect a history of residential and land-use zoning with the socio-natural relations of planting and sustaining urban trees.     

Shifting borders,shifting center: hedging-out uncertainty in west Jerusalem’s urban core

ABSTRACT

This article argues that contested cities are inherently characterized by uncertainty and uses the interconnections between conflict, uncertainty and urban planning as a new analytical framework for investigating conflict cities. In the contested city of Jerusalem, geopolitical uncertainty stems from the Israeli occupation over East Jerusalem. Focusing on recent urban regeneration plans for West Jerusalem’s city center, the article explores how the municipality locates, plans and imagines the city center when the city’s external and internal boundaries are contested and unfixed. A two-tier analysis is employed. First, a historical analysis shows that the “city center”, as defined by authorities, is an unfixed locale that shifts in concurrence with shifts in the city’s boundaries. Then, a geopolitical analysis shows that by shifting the city center’s boundaries, the Israeli authorities decouple the city’s economic development (in the west) from Israel’s continuing ethno-national policies (in the east).     

Policing perception: postpolitics and the elusive everyday

ABSTRACT

This piece argues that urban postpolitical scholarship should pay greater attention to the everyday lives of urban residents and the everyday spaces of contemporary cities. Recent debates in urban geography have sought in part to expand narrow readings of Jacques Rancière’s politics in particular, creating space for broader and more inclusive analyses of resistance to depoliticizing regimes. This article builds on this work, extending these critiques by suggesting that the quotidian is the most pressing analytical avenue for such expansion. The piece builds on ethnographic and archival fieldwork conducted in Mexico City between 2014 and 2017, demonstrating the dependence of a postpolitical regime on the maintenance of particular relations in the everyday spaces and interactions of the city, and some of the salient ways these trends are experienced, reproduced, and contested by the city’s residents.     

A look inside the struggle for housing in Buenos Aires,Argentina

Set in the broader context of increasing urban precarity and displacement of the urban poor and working classes, this paper examines the social and collective significance of housing precarity and eviction as it is experienced by Latin American, immigrant families living in informal hotels in Buenos Aires, Argentina. I analyze the internal dynamics, interactions and relationships between residents of informal hotels, the housing organization CIBA (Coordinadora de Inquilinos de Buenos Aires), which fights for housing rights for the poor in the city, and the city government sponsored housing subsidy. I argue that urban precarity severely limits opportunities for collective organization around better housing and political and social change. I show that despite CIBA’s objectives to transform social and political conditions for the poor in Buenos Aires, residents often operate under other assumptions and goals, in part because of the temporal and spatial restraints under which they live. Instead, residents of informal hotels work with CIBA in order to secure access to basic, urgent needs. These different expectations and understandings produce contentious relationships of dependence and subordination that are exacerbated by the eviction process and the city government housing subsidy.     

Management Challenges for Aboriginal Cultural Heritage in Peri-urban Queensland

It is often assumed that places of cultural significance to Aboriginal and Torres Strait Islander peoples are protected under cultural heritage legislation such as the Aboriginal Cultural Heritage Act 2003 in Queensland. Such Acts are improvements on previous policies, which all but neglected Aboriginal cultural heritage. Nevertheless, the aims of policies developed at wider geographic scales, such as States within the Australian system, continue to be disconnected from the experiences of some local Traditional Owners. In this paper, we examine conflicts between non-local policy and on-ground management decisions for Aboriginal cultural heritage in peri-urban Queensland. We focus on the challenges of local Traditional Owners in peri-urban landscapes, basing our discussion on recent experiences conducting research on Indigenous land management in southeast Queensland. We examine three case studies: one in which colonial heritage values were prioritised over existing Aboriginal cultural heritage values, a second where local government failed to support a private landholder’s attempt to identify and protect a cultural heritage site, and a third where a cultural heritage site was protected but in a way that restricts the continuation of cultural practices. Developing more productive and equitable relationships between Traditional Owners and non-Indigenous decision makers, with regards to Aboriginal cultural heritage, requires new locally developed processes for engagement and we suggest how this could be achieved.     

Buenos Aires,capital of tango: tourism,redevelopment and the cultural politics of neoliberal urbanism

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.     

The Place of Narrative in the Study of Third World Migration: The Case of Spontaneous Rural Migration in Sri Lanka*

Studies of migration in geography have most often been based on quantitative research approaches. Such studies cannot adequately shed light on the contextuality of migration and the individual decision-making processes involved. Personal narratives express individual experiences within a social context. The story of “Amma,” a female rural migrant in Sri Lanka, shows the role of women in migration, the importance of family ties, the contextual causes of migration, and characteristics of the migration flow per se. Personal narratives have an underutilized potential of capturing the variety of migrants' experiences and the complexity of the decision to migrate.     

The impact of tree cover loss on land surface temperature: A case study of central Massachusetts using Landsat Thematic Mapper thermal data

Land surface temperature (LST) variability results from diversity in urban surface materials over space and time such that locations with impervious urban cover experience higher temperature and larger temperature variation compared to non-impervious cover. There is growing awareness that warmer temperatures in urban locations negatively impact city residents by increasing heat related death and energy usage during heat waves. However, little previous work investigates the linkages between urban tree cover loss events related to invasive species eradication and urban heat trends. This paper examines the variation in LST using Landsat-5 Thematic Mapper (TM) thermal imagery in Worcester County, Massachusetts where over 30,000 trees were removed since 2008 to eradicate the invasive Asian Longhorned Beetle (ALB), most of which existed in urban residential areas. Throughout the study area a 10% loss in tree canopy cover caused a 0.7 °C increase in LST whereas a 10% increase in sub-canopy impervious surface area exposed due to tree loss caused 1.66 °C increase in LST. The Burncoat and Greendale neighborhoods in northern Worcester experienced a combined 48% tree cover loss from 2008 to 2010 due to ALB eradication and an average relative LST increase of 2.4 °C (range 0.6–4.1 °C). Given that areas with an increase in exposed impervious surface produce greater temperature increases than areas of tree loss, future tree replanting efforts may focus on locations that reduce exposed impervious surfaces.     

农业文化遗产社区角色认同对旅游参与的影响研究——以浙江省青田县龙现村为例

探究居民作为农业文化遗产传承者的角色认同是否影响其参与旅游,是农业文化遗产地可持续旅游研究的重要问题。基于角色认同理论,以全球重要农业文化遗产保护试点项目浙江青田稻鱼共生系统为例,利用时间日志法和半结构式访谈法获取当地居民时间利用数据,并从时间利用视角出发就居民角色认同对其旅游参与的影响进行质性探讨,以期深度挖掘居民的态度和心理感知。结果表明:居民作为农业文化遗产传承者,其角色认同对旅游参与具有一定的影响。以居民角色认同程度和旅游参与程度作为分类变量加以交互组合,形成4种常见的旅游社区参与类型,即高角色认同-深度参与旅游型居民、高角色认同-浅度(未)参与旅游型居民、低角色认同-浅度(未)参与旅游型居民、低角色认同-深度参与旅游型居民。从而针对不同类型居民,提出农业文化遗产旅游参与和遗产保护的可行性建议。     

Assessing Natural and Cultural Determinants of Urban Forest Quality in Nanjing (China)

This study assessed underlying natural and cultural determinants of tree health and ways to improve urban forest performance in compact Nanjing city. Two groups of factors were investigated: (1) habitat conditions, including planting site, ground-cover, land cover, and district; and (2) tree traits, including species provenance and seasonality, and tree dimensions. A stratified sampling strategy selected 6351 trees for detailed assessment. The data were analyzed by multivariate logistic regressions. Institutional, park-garden and industrial trees with more open-space sites with vegetated ground-cover performed better than roadside and residential ones. Poor trees in confined residential sites deviated from those in other cities. Park-garden sites did not always nurture meritorious, large and diversified trees. District differentiation in tree performance was related to land cover. Exotic and evergreen species grew better than indigenous and deciduous, offering hints on species-habitat matching. Detailed field and statistical analyses could yield tree-environment information to enhance urban forestry research and management.     

Using the commons to understand the Dutch elm disease epidemic in Syracuse,NY

Prior to the arrival of Dutch elm disease to the United States in 1930, American elm (Ulmus americana) had become one of the most beloved and commonly planted urban trees throughout the country, especially in the Northeastern United States. The trees were revered for their beauty, hardiness, and the corridor‐like shade provided to city streets. Syracuse, NY stands as an example of this popularity: in 1951, when the disease first arrived in the city, over 50,000 elms grew in the city. But over the course of twenty years, nearly all elms in the city had become infected and succumbed to the disease. Although efforts to control the fungus in Syracuse ultimately failed to stop elm loss, the case study can be used to better inform contemporary urban forest management practices today by highlighting the effects of mixed property ownership in cities and its effects on pest management.     

Livelihoods and the transformative potential of cities: Challenges of inclusive development in Rustenburg,North West Province,South Africa

Urban geographers increasingly incorporate the potential of so‐called informal livelihood activities to provide resources that can be creatively managed in the transformation of urban space, particularly to the benefit of less well off and marginalized residents. This paper reports a case study in Rustenburg, North West Province, South Africa, where city managers began to promote inclusive development in the early 1990s, just prior to the formal dismantling of the apartheid system. The findings reveal that Rustenburg's urban transformation process, over a decade later, continued to reproduce repressive practices that limit the informal livelihood activities of the urban majority. Apparently efforts of well‐meaning city managers to implement a sustainable and inclusive development process are often rendered futile at the point of actually defining the constituents of urban socioeconomic transformation.     

Patterns and dynamics of urban forests in relation to land use and development history in Guangzhou City, China

Trees in cities display a varied pattern that is often moulded by a city's physical fabric and its evolution through time. The town plan expressed in spatial dimension as land use, and in temporal sense as development history, furnishes a framework to evaluate the intricate association between city and trees. Guangzhou city, the premier metropolis of south China, has been established for 2800 years, and has a long history of urban greening and heterogeneous land use. Five urban districts, which represent old, middle-aged and young stages of development and cover the bulk of the city's built-up zones, form the study area. Interpretation of aerial photographs is used as a basis to classify the urban forest into three types, and to design a sampling scheme for studying trees in urban parks, institutional grounds and roadsides. District history has bequeathed a plethora of configurations in terms of buildings, roads and land uses, accompanied by plantable spaces of dissimilar dimensions, geometry and quality. The districts display diverse tree attributes such as frequency, density and species diversity. Young districts, with lower density, more institutional uses and wider roads, present more opportunities for greening. Recent shifts in landscape fashion have introduced a significantly different treescape. A few exceptionally large parks and institutional sites play a pivotal role in the city's tree assets. Parks, roadsides and institutional forests have different tree-stocking rates and species assemblages. Implications for future planting and management of urban trees in different situations, and for the greening of other cities in China, and other developing countries, are explored.     

遗产化进程中遗产认同的内涵及形成路径——以世界遗产永顺老司城为例

为了解析群体间认同差异以及掌握群体认同的转变特性,首先从遗产认同的概念出发,从主客体的视角提出其操作化的定义,并构建了遗产认同的形成路径。随后在此理论框架下,以世界文化遗产永顺老司城为案例地进行理论演绎研究,运用文献资料法、半结构访谈法收集资料,运用话语分析法清洗资料。研究发现:1)老司城遗产认同的客体是遗产化进程中遗产本身被生产、被界定、被再利用以及被破坏等的产物。即中央治理少数民族地区的政治场所,是被认定的各级遗产,是解决居民生计和提高生活幸福感的工具,亦是重要的文化旅游资源。2)老司城遗产认同的主体是遗产化进程中遗产附着群体对遗产的认知、情感、评价和行为等方面。即政府和管理机构工作人员眼中具有独特价值的文化遗产,是带动当地发展的旅游资源;专家学者用以研究土司文化的重要考古点;居民眼中增强族群凝聚力且带来生活改善的历史遗留;游客用以收获新知和感受民族情怀的民族文化遗产。不同群体的遗产认同表现出了非均质性。3)老司城遗产认同客体和主体都具有转变性,这是由在遗产化过程中遗产本身的功能以及遗产附着群体对遗产的不同利用所决定的。因此,根据遗产化进程制定相应的遗产发展战略,引导不同群体形成积极认同,正确展示遗产价值,对遗产保护利用、遗产地治理工作有重要意义。     

Neighborhood-scale urban form,travel behavior,and CO2 emissions in Beijing: implications for low-carbon urban planning

With an increasing awareness of global climate change, the effect of urban spatial organization, at both city and neighborhood scales, on urban CO₂ emission reduction has attracted much scholarly and practical attention. Using Beijing as a case study, this article examines the extent to which neighborhood-scale urban form may contribute to reduction of travel-related CO₂ emissions in the context of rapid urbanization and spatial transformation. We derive complete travel-activity records of 1,048 residents from an activity diary survey conducted in 2007. Analysis using structural equation models finds that residents living in a neighborhood with higher land use mix, public transit accessibility, and more pedestrian-friendly street design tend to travel in a “low-carbon” manner and emit less CO₂ in daily travel, even controlling for residential and travel preferences. This article offers empirical evidence that sheds light on debates about policy measures to facilitate China’s transition toward sustainable and low-carbon urban development.