228 resultados para Urban Anthropology
Resumo:
The European Commission’s Biocidal Products Directive (Council Directive 98/8 EC), known as the BPD, is the largest regulatory exercise ever to affect the urban pest control industry. Although focussed in the European Union its impact is global because any company selling pest control products in the EU must follow its principles. All active substances, belonging to 23 different biocidal product types, come within the Directive’s scope of regulatory control. This will eventually involve re-registration of all existing products, as well as affecting any new product that comes to the market. Some active substances, such as the rodenticides and insecticides, are already highly regulated in Europe but others, such as embalming fluids, masonry preservatives, disinfectants and repellents/attractants will come under intensive regulatory scrutiny for the first time. One of the purposes of the Directive is to offer enhanced protection for human health and the environment. The potential benefit for suppliers of pest control products is mutual recognition of regulatory product dossiers across 25 Member States of the European Union. This process, requiring harmonisation of all regulatory decision-making processes, should reduce duplicated effort and, potentially, allow manufacturers speedier access to European markets. However, the cost to industry is enormous, both in terms of the regulatory resources required to assemble BPD dossiers and the development budgets required to conduct studies to meet its new standards. The cost to regulatory authorities is also tremendous, in terms of the need to upgrade staff capabilities to meet new challenges and the volume of the work expected by the Commission when they are appointed the Rapporteur Member State (RMS) for an active substance. Users of pest control products will pay a price too. The increased regulatory costs of maintaining products in the European market are likely to be passed on, at least in part, to users. Furthermore, where the costs of meeting new regulatory requirements cannot be recouped from product sales, many well-known products may leave the market. For example, it seems that in future few rodenticides that are not anticoagulants will be available within the EU. An understanding of the BPD is essential to those who intend to place urban pest control products on the European market and may be useful to those considering the harmonisation of regulatory processes elsewhere. This paper reviews the operation of the first stages of the BPD for rodenticides, examines the potential benefits and costs of the legislation to the urban pest control industry and looks forward to the next stages of implementation involving all insecticides used in urban pest management.
Resumo:
Port of Spain, Trinidad offers an ideal context in which to analyze pre-retirement return migration to a Global South urban realm, expanding transnational urban research beyond the conventional focus on Global North metropolitan destinations. In this article, we draw on the transnational narratives of a selected sample of relatively youthful Trinidadians, who have spent many years abroad acquiring education and professional experience, but who have then decided to return in mid-career to the capital region of the island nation of their birth, or of their parent(s). Theoretically, we position these returning professionals as members of a "middling" transnational urban class whose return is at least partly motivated by a desire to "make a difference." Our results contribute to a growing literature that documents the role of transnational middle-class urban elites returning elsewhere in the Carribbean: "middling" transnational urbanism is reshaping key facets of urbanization in the Global South.
Resumo:
Hardcore, or long-term derelict and vacant brownfield sites which are often contaminated, form a significant proportion of brownfield land in many cities, not only in the UK but also in other countries. The recent economic recession has placed the economic viability of such sites in jeopardy. This paper compares the approaches for bringing back hardcore brownfield sites into use in England and Japan by focusing on ten case studies in Manchester and Osaka, using an `agency'-based frame- work. The findings are set in the context of (i) national brownfield and related policy agendas; (ii) recent trends in land and property markets in both England and Japan; and (iii) city-level comparisons of brownfields in Manchester and Osaka. The research, which was conducted during 2009 ^ 10, suggests that hardcore brownfield sites have been badly affected by the recent recession in both Manchester and Osaka. Despite this, not only is there evidence that hardcore sites have been successfully regenerated in both cities, but also that the critical success factors (CSFs) operating in bringing sites back into use share a large degree of commonality. These CSFs include the presence of strong potential markets, seeing the recession as an opportunity, long-term vision, strong branding, strong partnerships, integrated development, and getting infrastructure into place. Finally, the paper outlines the policy implications of the research.
Resumo:
The property development industry is a key actor in UK brownfield regeneration projects. UK policy has attempted to interlink ‘sustainable development’ and ‘sustainable brownfield’ policy agendas, which have found an additional focus through the UK government’s ‘Sustainable Communities Plan’, part of a growing international emphasis on sustainable development. This paper examines the emergence of these agendas and related policies, and the role of the property development industry in the regeneration of six differing brownfield sites, based in Thames Gateway and Greater Manchester. Using a conceptual framework, the paper investigates aspects of the sustainability of these projects and highlights key lessons from them for both the UK and overseas. The research is based on structured interviews with a variety of stakeholders, including developers, planners, consultants and community representatives to highlight emerging best practice and related policy implications.
Resumo:
The majority of the world’s population now live in cities. This poses great challenges, but also great opportunities in terms of tackling climate change, resource depletion and environmental degradation. Policy agendas have increasingly focused on how to develop and maintain ‘integrated sustainable urban development’, and a number of theoretical conceptualisations of urban transition have been formulated to help our thinking and understanding in both developed and developing countries. Drawing on examples around the world the paper aims to examine the key ‘critical success factors’ that need to be in place for cities to traverse a pathway to a more sustainable future in urban development terms by 2050. The paper explores how important the issues of ‘scale’ is in the context of complexity and fragmentation in the city’s built environment, identifies the lessons that can be learned for future sustainable urban development, and the further research which is needed to address future urban transitions to 2050.
Resumo:
This chapter examines the workings of urban microclimates and looks at the associated causes and effects of the urban heat island (UHI). It also clarifies the relationship between urban form and the key climatic parameters (sun, daylight, wind, temperature). A particular section is devoted to the concepts of UHI intensity and sky view factor (SVF); these are useful indicators for researchers in this area. The challenge of how to model urban microclimates is covered, featuring the six archetypal urban forms familiar to analysts involved in using simulation software. The latter sections address the issue of urban thermal comfort, the importance of urban ventilation and finally what mitigating strategies can be implemented to curb negative UHI effects.
Resumo:
Flow along rivers, an integral part of many cities, might provide a key mechanism for ventilation – which is important for air quality and heat stress. Since the flow varies in space and time around rivers, there is limited utility in point measurements. Ground-based remote sensing offers the opportunity to study 3D flow in locations which are hard to observe. For three months in the winter and spring of 2011, the atmospheric flow above the River Thames in central London was observed using a scanning Doppler lidar, a dual-beam scintillometer and sonic anemometry. First, an inter-comparison showed that lidar-derived mean wind-speed estimates compare almost as well to sonic anemometers (root-mean-square error (rmse) 0.65–0.68 m s–1) as comparisons between sonic anemometers (0.35–0.73 m s–1). Second, the lidar duo-beam scanning strategy provided horizontal transects of wind vectors comparison with scintillometer rmse 1.12–1.63 m s–1) which revealed mean and turbulent flow across the river and surrounds; in particular: chanelling flow along the river and turbulence changes consistent with the roughness changes between built to river environments. The results have important consequences for air quality and dispersion around urban rivers, especially given that many cities have high traffic rates on bankside roads.
Resumo:
The first part of this review examines what is meant by ‘urban land and property’ (ULP) and looks at the background of ULP in the light of trends in UK urban areas over the past 50 years. Key conceptual approaches to the ULP ‘ownership issue’ are identified, together with the constraints to empirical analysis, which include a lack of data and patchy and inconsistent datasets. Three main components of ULP ownership in the UK are then examined using published data on commercial property, residential property and urban land, including ‘previously developed land’ (PDL) and ‘development land, covering both the private and public sectors. The review examines past trends in ULP ownership patterns in these sectors within the UK, and the key drivers which have created the present day patterns of ULP ownership. It concludes by identifying possible future trends in ULP ownership over the next 50 years to 2060 in the three main ULP sectors.
Resumo:
Within a changing climate, Mediterranean ‘Garrigue’ xerophytes are increasingly recommended as suitable urban landscape plants in north-west Europe, based on their capacity to tolerate high temperature and reduced water availability during summer. Such species, however, have a poor reputation for tolerating waterlogged soils; paradoxically a phenomenon that may also increase in north-west Europe due to predictions for both higher volumes of winter precipitation, and short, but intensive periods of summer rainfall. This study investigated flooding tolerance in four landscape ‘Garrigue’ species, Stachys byzantina, Cistus × hybridus, Lavandula angustifolia and Salvia officinalis. Despite evolving in a dry habitat, the four species tested proved remarkably resilient to flooding. All species survived 17 days flooding in winter, with Stachys and Lavandula also surviving equivalent flooding duration during summer. Photosynthesis and biomass production, however, were strongly inhibited by flooding although the most tolerant species, Stachys quickly restored its photosynthetic capacity on termination of flooding. Overall, survival rates were comparable to previous studies on other terrestrial (including wetland) species. Subsequent experiments using Salvia (a species we identified as ‘intermediate’ in tolerance) clearly demonstrated adaptations to waterlogging, e.g. acclimation against anoxia when pre-treated with hypoxia. Despite anecdotal information to the contrary, we found no evidence to suggest that these xerophytic species are particularly intolerant of waterlogging. Other climatic and biotic factors may restrict the viability and distribution of these species within the urban conurbations of north-west Europe, but we believe increased incidence of flooding per se should not preclude their consideration.
Resumo:
Carbon monoxide (CO) concentration data from 1999–2006, monitored at 5 different pollution stations in a high-rise mega city (Hong Kong), were collected and investigated. The spatio-temporal characteristics of urban CO concentration profiles were obtained. A new approach was put forward to examine the relationship between urban CO concentration and different wind flow patterns. Rather than relying on the meteorological data from a single weather station, usually adopted in previous studies, four weather stations on the boundary of Hong Kong territory were used in the present study so as to identify 16 different wind flow patterns, among which a typical urban heat island circulation (UHIC) can be distinguished. Higher concentrations were observed to be associated with the flow pattern of an inflow from Lau Fau Shan (LFS) station which is located in the northwest of Hong Kong. This suggests that the ability of dilution for north-to-west wind is relatively weak due to the pollutants carried from outside Hong Kong. The effectiveness of wind speed on the alleviation of urban concentration is dependent on the initial concentration of the approaching wind. The increase of wind speed of north-to-west wind from 0 m/s to 6 m/s has little effect on the reduction of urban CO concentration, especially on the non-roadside stations. By contrast, for the southerly marine wind, pollution concentration decreases sharply with an increase in the wind speed. It was also found that urban heat island circulation (UHIC) is conducive of the accumulation of pollutants, especially at night. There exists a positive correlation between CO concentration and UHI intensity. This correlation is much stronger at night compared to during the day. Keywords: urban pollution monitoring, urban ventilation pattern, urban heat island circulation, mega city
Resumo:
This paper reports the results of a parametric CFD study on idealized city models to investigate the potential of slope flow in ventilating a city located in a mountainous region when the background synoptic wind is absent. Examples of such a city include Tokyo in Japan, Los Angeles and Phoenix in the US, and Hong Kong. Two types of buoyancy-driven flow are considered, i.e., slope flow from the mountain slope (katabatic wind at night and anabatic wind in the daytime), and wall flow due to heated/cooled urban surfaces. The combined buoyancy-driven flow system can serve the purpose of dispersing the accumulated urban air pollutants when the background wind is weak or absent. The microscopic picture of ventilation performance within the urban structures was evaluated in terms of air change rate (ACH) and age of air. The simulation results reveal that the slope flow plays an important role in ventilating the urban area, especially in calm conditions. Katabatic flow at night is conducive to mitigating the nocturnal urban heat island. In the present parametric study, the mountain slope angle and mountain height are assumed to be constant, and the changing variables are heating/cooling intensity and building height. For a typical mountain of 500 m inclined at an angle of 20° to the horizontal level, the interactive structure is very much dependent on the ratio of heating/cooling intensity as well as building height. When the building is lower than 60 m, the slope wind dominates. When the building is as high as 100 m, the contribution from the urban wall flow cannot be ignored. It is found that katabatic wind can be very beneficial to the thermal environment as well as air quality at the pedestrian level. The air change rate for the pedestrian volume can be as high as 300 ACH.