Detecting the scales at which birds respond to structure in urban landscapes

Little empirical information exists about how birds respond to urban landscape structure across multiple scales. We explored how the variation in percent tree canopy cover, at four different scales, affected the abundance of bird species across various urban sites in North America. Bird counts were derived from previous studies, and tree patches were measured from aerial photographs that represented areas of 0.2 km², 1.5 km², 25.0 km², and 85.0 km². At each of the four areas, we conducted regressions between bird counts and percent cover of various tree patch sizes. From these analyses, we determined the area (called the best prediction area—BPA) and the patch size (called the best patch size—BPS) that accounted for a significant amount of the variation in bird counts, beyond the variation accounted for by these parameters measured at other scales. BPA and BPS were calculated primarily to take into account the high degree of collinearity that existed among the amount of tree canopy cover measured across the four scales.We calculated BPA and BPS values for a variety of bird species and ascertained whether larger species had relatively larger BPS and BPA values. In the spring, middle-sized to large birds (16.6 g–184.0 g) had relatively larger BPS values than did smaller birds (3.2 g–16.5 g), but in the summer, the largest birds (61.7 g–576.0 g) had small BPS values. Spring BPA values showed a similar result but summer BPA values did not. A majority of birds of all sizes had summer BPA values at the finer scales of 0.2 km² and 1.5 km². Overall, body size was an approximate predictor of the area and patch size at which a species responds to trees in a landscape, but many exceptions did occur. These exceptions could be related to a variety of factors, one being the difficulty in relating human-biased measurements to avian measurements of a landscape. The method described in this study will help researchers design multi-scale studies to address the effect of landscape pattern on different animal species.     

Urban and peri-urban aquaculture as an immediate source of food fish: Perspectives of Dhaka City,Bangladesh

This paper describes the present status of aquaculture activities in Dhaka City and its surrounding areas including the system of fish marketing and distribution and environmental and socioeconomic issues. Dhaka City contains over 10 million people and is expanding day by day. Demand of fish in the last 10 years has increased as a result of increases in population and income levels. The annual per capita consumption of fish is reported to drop by 0.5 kg since 1985. The reason for this decline is increased prices and decreased supply of fish. Fish supply to the city comes from catch in the rivers-estuaries and floodlands of Dhaka district, neighboring districts, imports from other areas and aquaculture in surrounding areas of the city. Considerable quantities of fish are imported from India, Myanmar and Thailand. Seasonal patterns are common both in supply and consumption of fish. Along with traditional rural household aquaculture, in recent years, urban and peri-urban aquaculture has also been popular. Three broad types of aquaculture activities are found in and around Dhaka City; these are polyculture of carp in ponds, monoculture of catfishs in ponds, and pen and cage aquaculture in open waters. The carp includes both Indian major carp and Chinese carp and some minor carp. The catfish group includes mainly Thai pangas (Pangasius sutchi). Tilapia (Oreochromis niloticus) is also widely popular among the farmers. The technology used for aquaculture is improved extensive to semi-intensive. Increasing demand for fish in the city markets has encouraged the expansion of peri-urban aquaculture with a corresponding increase in the proportion of farmed fish in the markets.     

Putting place on the menu: The negotiation of locality in UK food tourism,from production to consumption

This paper uses a case study of tourism in the Lake District and Exmoor to explore the relationship between ‘local food’ and sustainable rural tourism in the UK. Drawing on qualitative interviews with tourists, food producers and café, pub and restaurant owners, I use an approach based upon the commodity chain to trace the shifts in the discursive and material understandings of the ‘local’ that take place throughout the tourist food chain. These shifts are shown to occur in response to the need to negotiate the tensions between the ideals and the practicalities of food production and consumption which occur as a result of the relationships that exist throughout the food chain. Such conclusions are shown to be important for our understanding of the links between ‘local food’ and sustainable rural tourism because they indicate that we must attend to the values, as well as the practicalities, that drive the contemporary food sector at all stages of the food chain, from production to consumption.     

Asian urban sustainability in the era of globalization

The process of achieving urban sustainable development is uncharted. We only know that plans should address the economic, environmental and social health of the city and this task can only be accomplished by approaching each of these issues at different scales. For rapidly developing world cities, “sustainability” is becoming an increasingly elusive objective, in part, because of impacts by forces beyond their borders. Using the Asia-Pacific region as a case study, a framework relates regional transnational flows to the state of the urban environment and the social conditions of linked rapidly developing cities. The “functional city system” within the Asia-Pacific increasingly is both the engine of urban growth and the force behind differentiating urban environmental and social issues. At the same time, while globalization forces have been particularly strong within cities in the Asia-Pacific, local factors also play a crucial role in urban development. Globalization driven growth has not translated into a single path of development, rather localities have demonstrated contextually specific paths.     

Dialogic landscapes: Toward a nuanced understanding of globalization in urban Indonesian signage

This article shows that a perspective rooted in Bakhtin's dialogism between the fixed centripetal and fluid centrifugal forces of language and culture is useful in achieving a nuanced understanding of globalization in general and semiotic landscapes in Indonesia in particular. Drawing on data from Indonesia, this article shows dialogic interconnections between fixed and fluid notions of languages and cultures through a multimodal and indexical analysis of governmental and commercial signage in the urban center of Semarang, the provincial capital of Central Java. The analysis highlights the nuanced localizing and globalizing strategies in signage and how dialogicity helps shape the semiotic landscape.     

Social dimensions of gradients in urban ecosystems

Urban ecosystems are complex mosaics in which the biophysical characteristics are transformed over time by a concentrated, diverse set of human activities. Understanding their complexity requires the continuing development of interdisciplinary approaches. The use of gradient approaches has pointed towards the need to examine in greater detail the roles of human influences. In this paper, I propose the addition of three social dimensions to characteristics defining urban gradients: landuse, land management effort, and historical context. These dimensions correspond with major types of social activities that modify the physical environment. They are intended to augment research by explicitly elaborating on the social factors contributing to the variation along the complex, indirect gradients that typify urban areas.The diversity of urban landuses has numerous influences, obvious and subtle, on the complex urban land gradients. Incorporating new information on historical and spatial characteristics of management practices supports more direct fine-scale analyses of the impact of human activities on the environment. This path of inquiry also requires engaging in more detailed research on historical dimensions of urban development in conjunction with biophysical analyses. Examples from Columbia, South Carolina, illustrate the ways that social and historical processes contribute to urban ecology.     

A critical review on current practices of the monitoring and evaluation in the preparation of strategic urban plans within the Egyptian context

Worldwide, strategic urban planning is found in very different contexts and planning schemes, where it is always a tool strongly linked to enhancing urban management. Under the umbrella of strategic urban planning different approaches can be perceived, in which within these broad shared characteristics there are significant variations. A key component in the strategic urban planning process is the monitoring and evaluation (M&E) element and these differences can be seen in the way that M&E is approached. Egypt is currently on the track to reform its planning system shifting from the conventional master plans towards strategic urban plans (SUPs). This paper reflects on the current practices of M&E the preparation of SUPs within the Egyptian context. It sheds light on the strengths and weaknesses of the employed techniques and concludes with some recommendations to improve the process of M&E, which builds upon the strengths in the employed techniques.     

Ultraviolet radiation in urban ecosystems with consideration of effects on human health

Excess exposure to ultraviolet radiation (UV) from the sun, particularly the ultraviolet B (UVB), is cited as a cause or contributing factor for deleterious effects on human health, including skin cancers and cataracts. Rates of skin cancer have increased greatly in recent years, and increased UVB caused by reductions in stratospheric ozone may be responsible for some of the increase in rates, though quantified estimates of the effect of the UVB changes on health have low certainty. UVB exposure also affects the function of the immune system, and the potential resulting effects on infectious diseases and immunizations are a concern. Epidemiological considerations suggest that peoples' routine exposure to UV in urban areas can be significant in adverse health effects, particularly for young children. Projected trends of ozone indicate that agreements to limit ozone-depleting substances are slowing the UVB increase, but high levels will continue and apparently impact health to the middle of the current century. Urban trees greatly reduce ultraviolet irradiance in their shade when they obscure both the sun and sky. Where trees or other structures obscure only the sun, leaving much of the sky in view, UVB irradiance will be greater than suggested by the visible shade. Since air pollutants influence the UVB above the canopy, and the overlying atmosphere is usually more polluted in urban than rural areas, additional above-canopy monitoring of UV in urban areas is needed for comparison to existing rural monitoring sites. Such monitoring would facilitate the development of computer models of urban effects on UV, which are needed for epidemiological investigations, public education, and urban planning.     

The gendered dimensions of bushfire in changing rural landscapes in Australia

This paper examines gender differences in awareness, preparedness and attitudes towards bushfire amongst landholders in rural landscapes affected by amenity-led in-migration in southeast Australia. It considers the potential of conceptualising bushfire not as a gender-neutral natural phenomenon but as an important means by which traditional gender roles and power relations within rural landscapes are maintained. Landholders were found to uphold conventional views of bushfire management as “men’s business” despite changing social circumstances. Consequently, key gender differences exist within landholders’ bushfire risk awareness, bushfire knowledge, the perceived need for bushfire preparedness measures, the willingness to perform certain tasks, and the belief in personal capacity to act. We argue that covert and less visible as well as overt gender roles and traditions are important factors in understanding landholders’ engagement with bushfire management. When gendered dimensions of bushfire are investigated in the context of hegemony, a paradox emerges between women choosing not to take control of their own bushfire safety and women being denied the opportunity to take control. The complex and contradictory actions and attitudes to bushfire that materialise through an analysis of gendered social experiences complicate attempts to create more gender-sensitive frameworks for bushfire management. The tenacious and embedded nature of gender role divisions within both public and private spheres was furthermore found to act as economic, social and political stumbling blocks for empowerment opportunities. Using a mixed-methods research approach, this paper maps out gendered dimensions of bushfire through landholders’ narratives and actions. The implications of these dimensions for bushfire management have direct relevance to recent international discussions of the vulnerability of the growing number of people living in bushfire-prone rural–urban interface areas.     

Poultry and policy in Ghana: Lessons from the periphery of an agricultural policy system

We analyze poultry‐related policy documents from Ghana and ask how the problems identified and the actions proposed have changed over time. The analysis highlights the fact of limited and poor quality data, and associated uncertainty, ambiguity and poor specification of both problems and interventions. It also points to a long‐term commitment to intensive commercial production as the preferred pathway to deliver more animal protein. However, in the face of persistent feed constraints and economic liberalization, imports of frozen chicken have sky‐rocketed since the early 2000s, and a new pathway has come to dominate. We discuss this outcome and what it says more generally about policy around minor crops and livestock species.     

The contentious politics of integrated urban development in District Six

An examination of the antagonistic relations between key stakeholders in the land restitution process in District Six reveals that development logjams can to a significant extent be attributed to the conflict between local authorities and the community. After an unsuccessful initial legal bid to preclude an individual claims process in favour of an integrated, state‐controlled development project, a Trust was established to formally represent claimants. A model of stakeholder collaboration was instituted under the auspices of the City's Integrated Development Plan, based on the centrality of planning and management expertise, and with a restricted role for public consultation and participation. Relations between the Trust and the City broke down in late 2006 following a protracted disagreement over development priorities and about where the locus of control for the project should reside. This signalled a need for a new approach to ‘integrated development’.     

Prototyping public friction: Exploring the political effects of design testing in urban space

The use of prototypes as testing instruments has become a common strategy in the innovation of services and products and increasingly in the implementation of “smart” urban policies through living labs or pilots. As a technique for validating hypotheses about the future performance of products or policies, prototyping is based on the idea of generating original knowledge through the failures produced during the testing process. Through the study of an experimentation and prototyping project developed in Santiago de Chile called “Shared Streets for a Low-Carbon District,” I analyse the technique of prototyping as a political device that can make visible (or invisible) certain entities and issues, determining what the experimental entities can do and say. I will show how the technique of prototyping defines modes of participation, what is visible and thinkable, what can be spoken and what is unspeakable. In this sense, I examine two ambivalent capacities of prototyping: as a mechanism of management and enrolment that seeks to prescribe normativities (problem-validating prototype) and as an event that can make frictions tangible, articulating matters of concern and ways to open up alternative scenarios (problem-making prototype).     

Creating a community of practice among college campus food pantry directors in Michigan

There is increased awareness of hunger and food insecurity on college campuses. Recent estimates suggest that food insecurity affects as many as 4 out of 10 college students. As a result, over 650 US colleges have established campus food pantries. The College and University Pantries (CUP) research team at the University of Michigan–Dearborn has worked to create a community of practice in Michigan among campus pantry directors by hosting 2 summits designed around networking, problem-solving, and sharing best practices. This article describes the Michigan community of practice as an example for other regions doing similar work.     

Physical and chemical properties of a Hong Kong roadside soil in relation to urban tree growth

Tree planting in urban areas faces many limitations that suppress performance and increase management burdens. Soil problems are increasingly recognized as an important cause of establishment failures and declines. Recent city-greening programs in Hong Kong necessitate a better understanding of soil difficulties, but relevant information is lacking. A detailed study of physical and chemical properties of a representative roadside soil provides baseline data on edaphic restrictions and hints for correction and amelioration. The soil depth is inadequate for normal root expansion of trees, is excessively stony and sandy, and is beset by poor structure and heavy compaction. Root growth is likely to be restricted by the low levels of porosity and high shear strength. The densely packed surface layer reduces aeration and water movement into the lower layers. The nutrient stock is meager, and the ability to hold available moisture and nutrients is very limited. Soil reaction comparing with local natural soil is uncharacteristically alkaline with pH reaching 8.5 which may induce iron and manganese deficiency. Heavy metals register elevated concentrations especially for lead and zinc, but do not attain phytotoxic levels. The common multiple substrate problems need to be addressed properly before trees are planted. Evaluation of selected soil attributes is advocated for all planting sites.     

Connectivity in urbanizing landscapes: The importance of habitat configuration,urban area size,and dispersal

Human activities affect both the amount and configuration of habitat. These changes have important ecological implications that can be measured as changes in landscape connectivity. I investigated how urbanization interacts with the initial amount and aggregation of habitat to change dispersal potential, restoration potential, and the risk of spatially extensive disturbances. I used a factorial set of simulated landscapes and subjected each landscape to habitat loss by overlaying 66 different US urban areas. I used a common connectivity metric, CONNECT, to assess the magnitude and direction of changes for a range of dispersal distances. My results show that the relationship between habitat loss and connectivity loss is non-linear and subject to interactions between the spatial patterns of habitat distribution, urban morphology, and dispersal capabilities. The implications of a given urban form vary widely as a function of habitat distribution and dispersal capabilities. This implies that impact assessments, restoration activities, and conservation planning should consider historical habitat distribution when evaluating observed changes in connectivity. While my results clearly show that more aggregated or continuous habitats are more vulnerable to connectivity loss, this approach can also be used to identify landscapes where restoring connectivity will be particularly effective, for example through placement of stepping stone habitats.     

The city from its margins: rethinking urban governance through the everyday lives of migrant women in Johannesburg

Drawing on ethnographic data, this article explores migrant women’s relationships and encounters with the state in South Africa’s largest city, Johannesburg. Focusing on the experiences of people in this marginal location, the article re-examines the notion of ‘urban governance’, which is often understood as the realm of formal urban institutions in which the state asserts its authority and regulatory powers. Through the everyday lives of migrant women we see that local urban practices are not simply shaped by the formalism of state rules and regulations, or their informal illegal counterparts. The way migrant women navigate the city, trade on the streets, and interact with the state and other urban actors illustrates that governance is co-constructed by a multitude of regimes, legal and illegal, visible and invisible. Indeed, women’s lives collapse the dichotomy of the official and unofficial, governed and ungoverned city, in ways that allow us to rethink how we conceptualise the city.     

Use of urban habitats by coyotes in the vicinity of Banff Alberta

Little information is available on the degree to which coyotes (Canis latrans) use urban habitats. In the past, interactions between coyotes and humans have precipitated several instances of coyote aggression towards humans. Consequently, I analyzed use of urban habitats by coyotes and the possibilities for aggressive encounters with humans. In this study, 11 radio-collared coyotes were monitored between July 1991 and September 1992. Use/availability analysis demonstrated a clear difference in use of natural habitats between summer and winter. Urban habitats were used in direct proportion to availability during all time periods, except during the day in summer when coyotes avoided intense human activity. Campgrounds were not an attraction during either season. For the most part, coyotes in the vicinity of Banff used habitats available to them regardless of human activity. Evidence does not suggest the coyote population in the vicinity of Banff is predisposed to aggression due to familiarity with humans. The relationship between the data and coyote aggression towards humans is discussed.     

The parenting role of African-American fathers in the context of urban poverty

This qualitative study examines low-income African-American fathers' perceptions of their parenting role and the strategies they employ to bring up children in poor urban neighborhoods. Focus groups and individual interviews were conducted with 36 fathers who had contact with their children at least twice a month. Men in the study expressed conventional views of their fathering roles as provider, nurturer, and teacher, but placed the most emphasis on ‘being there’ for their children, as their financial circumstances limited other forms of involvement. Many fathers felt their circumstances to be exacerbated by a hostile child-support system. They desired to teach their children alternatives to the negative practices and values they saw in their urban neighborhoods and to have the skills to prosper in mainstream society. Overall, the findings suggest that many low-income urban fathers already desire to be responsible fathers but see themselves as limited by material and structural challenges. Services and policies that promote the economic stability of low-income fathers are recommended.     

Wildlife conservation in urban greenways of the mid-southeastern United States

Goals related to wildlife conservation are stated or implied in many urban greenway plans, but the actual wildlife conservation value of urban greenways is unclear. We surveyed 72 km. of greenway consisting of 38 different greenway segments in six cities in the mid-southeastern United States to determine the presence or absence of red fox (Vulpes vulpes), grey fox (Urocyon cinereoargenteus), and white-tailed deer (Odocoileus virginianus), and to assess characteristics of the greenways and adjacent lands that might promote or limit the presence of these species in each greenway. We focused on fox and deer because these mammals, while habitat generalists, require diverse habitats within close proximity, and are more sensitive to human disturbance and have larger territories than the majority of urban wildlife in this region. Thus, they can serve as indicator species for these habitat values in urban greenways in the southeastern United States. Field observations and scent station inventories revealed that only 18 of the 38 greenway segments had either fox or deer, 12 had only fox, 6 had fox and deer, and none had deer alone. Greenway segments with more forest cover, wider corridors, greater amounts of adjacent natural or seminatural habitat, and forest connectivity between greenways and nonadjacent natural areas were more likely to have fox or deer present. Characteristics associated with fox and deer presence were not independent of each other. Because greenways with such characteristics tend to be surrounded by less urban areas, adjacent land use is a good predictor of fox and deer presence in the surveyed greenways. Whether greenways that are beneficial to fox and deer can be developed in urban settings is strongly site specific, because the greenway variables that appear most essential to these species are often dictated by the preexisting urban form and the vegetation in the vicinity of the greenway. Because the wildlife conservation value of urban greenways depends greatly on factors external to the greenway, greenways that have fox and deer present today may be particularly vulnerable to future changes in surrounding land use.