964 resultados para Urban areas.


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A visually apparent but scientifically untested outcome of land-use change is homogenization across urban areas, where neighborhoods in different parts of the country have similar patterns of roads, residential lots, commercial areas, and aquatic features. We hypothesize that this homogenization extends to ecological structure and also to ecosystem functions such as carbon dynamics and microclimate, with continental-scale implications. Further, we suggest that understanding urban homogenization will provide the basis for understanding the impacts of urban land-use change from local to continental scales. Here, we show how multi-scale, multidisciplinary datasets from six metropolitan areas that cover the major climatic regions of the US (Phoenix, AZ; Miami, FL; Baltimore, MD; Boston, MA; Minneapolis-St Paul, MN; and Los Angeles, CA) can be used to determine how household and neighborhood characteristics correlate with land-management practices, land-cover composition, and landscape structure and ecosystem functions at local, regional, and continental scales. © The Ecological Society of America.

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The recognition that urban groundwater is a potentially valuable resource for potable and industrial uses due to growing pressures on perceived less polluted rural groundwater has led to a requirement to assess the groundwater contamination risk in urban areas from industrial contaminants such as chlorinated solvents. The development of a probabilistic risk based management tool that predicts groundwater quality at potential new urban boreholes is beneficial in determining the best sites for future resource development. The Borehole Optimisation System (BOS) is a custom Geographic Information System (GIs) application that has been developed with the objective of identifying the optimum locations for new abstraction boreholes. BOS can be applied to any aquifer subject to variable contamination risk. The system is described in more detail by Tait et al. [Tait, N.G., Davison, J.J., Whittaker, J.J., Lehame, S.A. Lerner, D.N., 2004a. Borehole Optimisation System (BOS) - a GIs based risk analysis tool for optimising the use of urban groundwater. Environmental Modelling and Software 19, 1111-1124]. This paper applies the BOS model to an urban Permo-Triassic Sandstone aquifer in the city centre of Nottingham, UK. The risk of pollution in potential new boreholes from the industrial chlorinated solvent tetrachloroethene (PCE) was assessed for this region. The risk model was validated against contaminant concentrations from 6 actual field boreholes within the study area. In these studies the model generally underestimated contaminant concentrations. A sensitivity analysis showed that the most responsive model parameters were recharge, effective porosity and contaminant degradation rate. Multiple simulations were undertaken across the study area in order to create surface maps indicating areas of low PCE concentrations, thus indicating the best locations to place new boreholes. Results indicate that northeastern, eastern and central regions have the lowest potential PCE concentrations in abstraction groundwater and therefore are the best sites for locating new boreholes. These locations coincide with aquifer areas that are confined by low permeability Mercia Mudstone deposits. Conversely southern and northwestern areas are unconfined and have shallower depth to groundwater. These areas have the highest potential PCE concentrations. These studies demonstrate the applicability of BOS as a tool for informing decision makers on the development of urban groundwater resources. (c) 2007 Elsevier Ltd. All rights reserved.

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In this study, Evernia prunastri, a lichen growing in its natural habitat in Morocco was analysed for the concentration of five heavy metals (Fe, Pb, Zn, Cu and Cr) from eleven sites between Kenitra and Mohammedia cities. The control site was Dar Essalam, an isolated area with low traffic density and dense vegetation. In the investigated areas, the concentration of heavy metals was correlated with vehicular traffic, industrial activity and urbanization. The total metal concentration was highest in Sidi Yahya, followed by Mohammedia and Bouznika. The coefficient of variation was higher for Pb and lower for Cu, Zn and Fe. The concentrations of most heavy metals in the thalli differed significantly between sites (p<0.01). Principal component analysis (PCA) revealed a significant correlation between heavy metal accumulation and atmospheric purity index. This study demonstrated also that the factors most strongly affecting the lichen flora were traffic density, the petroleum industry and paper factories in these areas. Overall, these results suggest that the index of atmospheric purity and assessment of heavy metals in lichen thalli are good indicators of the air quality at the studied sites.

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Introduction

Since the 1980s there have been major policies and projects for the redevelopment of Dublin Docklands. These projects were mainly aimed at profitable development of office, commercial and residential space, without a sound plan that would preserve the identity or community of the area. The recent shift in policies and urban design principles in the Dublin Docklands Area Master Plan 2008 shows that policy makers have acknowledged that mistakes were made in the last decades of the 20th century. The current map of the Dublin Docklands Area Master Plan 2008 gives us useful information about these changes. The Ringsend/ Irishtown area, which has kept a great part of its urban form and community identity throughout centuries, is described as an ‘area of protection of residential and services amenities’ (DDDA, 2008, map A). Meanwhile, the area of the Grand Canal Docks, recently developed, is described with the objective ‘to seek the social, economic and physical development or rejuvenation
within an area of mixed use of which residential and enterprise facilities would be the predominant uses’ (DDDA, 2008, map A). This classification shows that recent development has been unable to achieve the cohesion and complexity of existing neighbourhoods, revealing flaws not only in policy, but also in the built environment and approaches to urban design.

The shift towards the consideration of more community participation reveals a need to understand the tradition and past of these communities, while the urban fabric of small plots in the existing neighbourhoods, therefore, seems to have a very important role in the conservation of identity of place and providing the opportunity for difference within regularity. On the other hand, the new fabric of residential block developments in the docklands denies the possibility of developing a sense of community, and by providing only regularity, does not leave space for difference.

This paper will address questions related to urban morphology and town analysis in the case of Ringsend and Irishtown. This will provide a tool to learn from the past and perhaps find new models of development that might be less detrimental for the heritage of cities and urban communities. One of the ideas of this paper is to adhere to the new tendency in conservation policies to provide a broader analysis of urban areas, not only considering individual monuments in cities, but also analysing the significance of urban morphology and intangible heritage. It forms part of an OPW Post- Doctoral Fellowship in Conservation Studies and Environmental History.1 Research has been carried out in different areas of urban history of Dublin’s southern waterfront, including infrastructure history and a thorough analysis of the letters of the Pembroke Estate of the 19th century, which included the areas of Ringsend and Irishtown. However, this paper focuses on the study of urban form of the area and its significance to Dublin’s heritage.

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Sustainable development comprises of three dimensions. The three dimensions are the environment, the social and the economic. There have been many indicators used to measure the three dimensions of sustainability. For example air pollution, consumption of natural resources, quality of open space, noise, equity and opportunities and economic benefits from transport and land use. Urban areas constitute the most crucial factor in the sustainability. Urban systems affect and are affected by natural systems beyond their physical boundaries and in general the interdependence between the urban system and the regional and global environment is not reflected in urban decision making. The use of energy in the urban system constitutes the major element in the construction and function of urban areas. Energy impacts across the boundaries of the three dimensions of sustainability. The objective of this research is to apply energy-use-indicators to the urban system as a measure of sustainability. This methodology is applied to a case study in the United Kingdom.

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Sectarian violence in the Northern Ireland is often perceived to be mostly confined to cities. The aim of this paper is to explore statistically what factors contribute to segregation preferences among young people living in rural and urban areas, using the 2005–2009 Young Life and Times (YLT) survey – an annual attitudes survey of 16-year-olds. The findings show that religious and national identities are the strongest predictors of segregation preferences among 16-year-olds, regardless of where they live and what background they have. Those living in rural areas of Northern Ireland are more supportive of residential, workplace and educational segregation than those living in more urban areas. This research highlights the need for government policy to take rurality into account. Nevertheless, some variables significantly determine segregation preferences regardless of where respondents live, such as attendance of segregated schools, being female, or strength of national and religious identity. Consequently, policy initiatives should continue to address the effect of segregation, especially in relation to education, and future research exploring social class and gender is recommended. In conclusion, the perception of the violent ‘urban spaces’ and the ‘peaceful countryside’ has to be challenged.

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Research on admissions to care homes for older people has paid more attention to individual and social characteristics than to geographical factors. This paper considers rural-urban differences in household composition and admission rates. Cohort: 51,619 people aged 65 years or older at the time of the 2001 Census and not living in a care home, drawn from a data linkage study based on c.28% of the Northern Ireland population.Living alone was less common in rural areas; 25% of older people in rural areas lived with children compared to 18% in urban areas. Care home admission was more common in urban (4.7%) and intermediate (4.3%) areas than in rural areas (3.2%). Even after adjusting for age, sex, health and living arrangements, the rate of care home admission in rural areas was still only 75% of that in urban areas.People in rural areas experience better family support by living as part of two or three generation households. Even after accounting for this difference, older rural dwellers are less likely to enter care homes; suggesting that neighbours and relatives in rural areas provide more informal care; or that there may be differential deployment of formal home care services.

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Death of a spouse is associated with increased mortality risk for the surviving partner (the widowhood effect). We investigated whether the effect magnitude varied between urban, rural and intermediate areas, assembling death records (2001-2009) for a prospective cohort of 296,125 married couples in Northern Ireland. The effect was greatest during the first six months of widowhood in all areas and for both sexes. Subsequently, the effect was attenuated among men in rural and intermediate areas but persisted in urban areas (HRs and 95% CIs: rural 1.09 [0.99, 1.21]; urban 1.35 [1.26, 1.44]). Among women the effect was attenuated in all areas (rural 1.06 [0.96, 1.17]; urban 1.09 [1.01, 1.17]). The impacts of spousal bereavement varied between urban and more rural areas, possibly due to variation in social support provided by the wider community. We identify men in urban areas as being in greatest need of such support and a possible target for health interventions.

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Death of a spouse is associated with increased mortality risk for the surviving partner (the widowhood effect), although the mechanisms driving the effect are poorly understood. After acute stress and grief have dissipated, mortality risk may be increased by loss of emotional and instrumental support for daily living and so we investigated whether social support at both the household and community levels moderated the influence of spousal bereavement on mortality risk.

We assembled death records from the Northern Ireland Mortality Study spanning almost nine years for a prospective cohort of 296,125 married couples enumerated in the 2001 Census. Presence of other adults within the household and urban/rural residence were used as measures of support at the household and community levels, with informal social support perceived to be strongest in rural areas. We used Cox proportional hazards models to estimate the effects of widowhood, sex, household composition and urban/intermediate/rural residence on all-cause mortality.

Elevated mortality risk during the first six months of widowhood was found in all areas and for both sexes (range of hazard ratios 1.24, 1.57). After more than six months the effect among men was attenuated in rural but not urban areas (HRs and 95%CIs 1.09 [0.99, 1.21] and 1.35 [1.26, 1.44] respectively). Among women the effect was attenuated in both rural and urban areas (HRs 1.06 [0.96, 1.17] and 1.09 [1.01, 1.17]). Mortality risk post bereavement was not associated with presence of other adults in the household.

We found some support for the hypothesis that informal social support is beneficial for reducing the impacts of spousal loss. Rural residence had a positive effect especially among men but presence of other adults in the household had no effect. The reasons for this discrepancy require further investigation and we identify men in urban areas as being at greatest risk in the long term.

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Migration and gender studies have focused on economically active heterogeneous couples and traditionally highlight a dominant male role in migration decision-making. The female partner is commonly portrayed as a 'trailing wife' or 'trailing mother' with the move found to have a negative effect on her employment prospects. Much less is known about if or how the balance of power shifts between husbands and wives when employment or career-motivated moves are removed from the decision-making process. This is analysed with reference to retirement migration to rural areas of the UK and involved interviews with both partners present. For this cohort of retired couples, and in common with the literature, migration during economically active life course stages demonstrates strong 'trailing wife' and 'trailing mother' tendencies. The male's decision to retire signalled the commencement of a retirement life course stage for the couple. However, in contrast to the earlier male dominated decision-making, retirement migration saw the emergence of a 'trailing husband' phenomenon. Wives appear to adapt most successfully to the new rural environment while many husbands found it difficult to adjust (at least initially) to the multiple life changes: moving from largely urban areas to a rural setting alongside exiting the workforce. The findings suggest that the role of leader/ follower changed during the course of these couples' lives together and in relation to their reasons for moving.

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Large construction projects create numerous hazards, making it one of the most dangerous industries in which to work. This element of risk increases in urban areas and can have a negative impact on the external stakeholders associated with the project, along with their surrounding environments. The aim of this paper is to identify and document, in an urban context, the numerous issues encountered by on-site project managers from external stakeholders and how they affect a construction project. In addressing this aim, the core objective is to identify what issues are involved in the management of these stakeholders. In order to meet this requirement, a qualitative methodology encompassing an informative literature review followed by five individual case study interviews. The data gathered is assessed qualitatively using mind mapping software. A number of issues are identified which have an impact on the external stakeholders involved, and also how they affected proceedings on site. Collectively the most commonly occurring issues are environmental, legal, health and safety and communication issues. These ranged from road closures and traffic disruption to noise, dust and vibrations from site works. It is anticipated that the results of this study will assist and aid project managers in identifying issues considering external stakeholders, particularly on urban construction projects. A wide range of issues can develop depending on the complexity and nature of each project, but this research will illustrate and reinforce to project managers, that identifying issues early, effective communication and appropriate liaising can be used to manage the issues considering external stakeholders.

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A poluição atmosférica constitui actualmente um grave problema ambiental cujos efeitos se fazem sentir a diversas escalas, desde os efeitos imediatos e de longo termo na saúde humana e nos materiais, até fenómenos regionais, como a acificação, e fenómenos globais que durante este século poderão alterar as condições de vida no globo. Apesar da redução das emissões de poluentes atmosféricos, conseguida através do uso de combustíveis mais limpos e tecnologias mais eficientes, as áreas urbanas continuam a evidenciar sinais de degradação ambiental. Para ser bem sucedida a cidade deve enfrentar as três dimensões da sustentabilidade: social, económica e ambiental. O modo de utilização do solo numa zona urbana é uma característica fundamental da cidade, com influência directa no seu desempenho ambiental e na qualidade de vida que proporciona à população. O presente trabalho explora a ligação entre a estrutura urbana e a qualidade do ar, um dos muitos aspectos do desenvolvimento urbano sustentável. A perspectiva histórica sobre o desenvolvimento urbano, a poluição atmosférica e a sua interligação é abordada, bem como o trabalho de investigação que tem vindo a ser conduzido na área. A aplicação de um sistema de modelação atmosférico a um caso de estudo idealizado demonstra a importância da estrutura espacial da cidade na sustentabilidade urbana, mostrando que cidades compactas com usos do solo misturados promovem uma melhor qualidade do ar quando comparadas com cidades dispersas, com baixa densidade populacional. De modo a explorar a relação entre a estrutura urbana e a qualidade do ar numa zona urbana real, a região urbana do Porto é identificada como um caso de estudo adequado, e o processo de crescimento urbano nas últimas décadas é analisado, assim como os níveis de qualidade do ar da região. De modo a definir a configuração do sistema de modelação mais adequada para a região de estudo, são efectuados diversos testes de sensibilidade com o modelo meteorológico. Relativamente ao modelo de qualidade do ar, é descrito e implementado um conjunto de acções de modo a melhorar o desempenho do modelo para a simulação das concentrações de poluentes na atmosfera urbana, no contexto de alterações do uso do solo. Finalmente, são desenvolvidos e testados, através da aplicação do sistema de modelação, dois cenários alternativos de desenvolvimento urbano para a área de estudo. Estes cenários alternativos implicam diferentes emissões de poluentes e diferentes distribuições espaciais dessas emissões, e como consequência, diferentes níveis de qualidade do ar. O estudo permite concluir que alterações nos padrões de uso do solo em áreas urbanas conduzem a alterações na meteorologia, emissões e qualidade do ar. As áreas urbanas dispersas, quando comparadas com estruturas urbanas compactas são responsáveis por temperaturas mais elevadas, emissões de poluentes para a atmosfera mais elevadas e maiores concentrações de poluentes.

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Urban soil quality may be severely affected by hydrophobic organic contaminants (HOCs), impairing environmental quality and human health. A comprehensive study was conducted in two contrasting Portuguese urban areas (Lisbon and Viseu) in order to assess the levels and potential risks of these contaminants, to identify sources and study their behaviour in soils. The concentrations of HOCs were related to the size of the city, with much higher contamination levels observed in Lisbon urban area. Source apportionment was performed by studying the HOCs profiles, their relationship with potentially toxic elements and general characteristics of soil using multivariate statistical methods. Lisbon seems to be affected by nearby sources (traffic, industry and incineration processes) whereas in Viseu the atmospheric transport may be playing an important role. In a first tier of risk assessment (RA) it was possible to identify polycyclic aromatic hydrocarbons (PAHs) in Lisbon soils as a potential hazard. The levels of PAHs in street dusts were further studied and allowed to clarify that traffic, tire and pavement debris can be an important source of PAHs to urban soils. Street dusts were also identified as being a potential concern regarding human and environmental health, especially if reaching the nearby aquatic bodies. Geostatistical tools were also used and their usefulness in a RA analysis and urban planning was discussed. In order to obtain a more realistic assessment of risks of HOCs to environment and human health it is important to evaluate their available fraction, which is also the most accessible for organisms. Therefore, a review of the processes involved on the availability of PAHs was performed and the outputs produced by the different chemical methods were evaluated. The suitability of chemical methods to predict bioavailability of PAHs in dissimilar naturally contaminated soils has not been demonstrated, being especially difficult for high molecular weight compounds. No clear relationship between chemical and biological availability was found in this work. Yet, in spite of the very high total concentrations found in some Lisbon soils, both the water soluble fraction and the body residues resulting from bioaccumulation assays were generally very low, which may be due to aging phenomena. It was observed that the percentage of soluble fraction of PAHs in soils was found to be different among compounds and mostly regulated by soil properties. Regarding bioaccumulation assays, although no significant relationship was found between soil properties and bioavailability, it was verified that biota-to-soil bioaccumulation factors were sample dependent rather than compound dependent. In conclusion, once the compounds of potential concern are targeted, then performing a chemical screening as a first tier can be a simple and effective approach to start a RA. However, reliable data is still required to improve the existing models for risk characterization.

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The better understanding of the interactions between climate change and air quality is an emerging priority for research and policy. Climate change will bring changes in the climate system, which will affect the concentration and dispersion of air pollutants. The main objective of the current study is to assess the impacts of climate change on air quality in 2050 over Portugal and Porto urban area. First, an evaluation and characterization of the air quality over mainland Portugal was performed for the period between 2002 and 2012. The results show that NO2, PM10 and O3 are the critical pollutants in Portugal. Also, the influence of meteorology on O3, NO2 and PM10 levels was investigate in the national main urban areas (Porto and Lisboa) and was verified that O3 has a statistically significant relationship with temperature in most of the components. The results also indicate that emission control strategies are primary regulators for NO2 and PM10 levels. After, understanding the national air quality problems and the influence that meteorology had in the historical air quality levels, the air quality modelling system WRF-CAMx was tested and the required inputs for the simulations were prepared to fulfil the main goal of this work. For the required air quality modelling inputs, an Emission Projections under RCP scenarios (EmiPro-RCP) model was developed to assist the estimation of future emission inventories for GHG and common air pollutants. Also, the current emissions were estimated for Portugal with a higher detailed disaggregation to improve the performance of the air quality simulations. The air quality modelling system WRF/CAMx was tested and evaluated over Portugal and Porto urban area and the results point out that is an adequate tool for the analysis of air quality under climate change. For this purpose, regional simulations of air quality during historical period and future (2045-2050) were conducted with CAMx version 6.0 to evaluate the impacts of simulated future climate and anthropogenic emission projections on air quality over the study area. The climate and the emission projections were produced under the RCP8.5 scenario. The results from the simulations point out, that if the anthropogenic emissions keep the same in 2050, the concentrations of NO2, PM10 and O3 will increase in Portugal. When, besides the climate change effects, is consider the projected anthropogenic emissions the annual mean concentrations of NO2 decrease significantly in Portugal and Porto urban area, and on the contrary the annual mean PM10 concentrations increases in Portugal and decrease in Porto urban area. The O3 results are mainly caused by the reduction of ozone precursors, getting the higher reductions in urban areas and increases in the surrounding areas. All the analysis performed for both simulations for Porto urban area support that, for PM10 and O3, there will be an increase in the occurrence of extreme values, surpassing the annual legislated parameters and having more daily exceedances. This study constitutes an innovative scientific tool to help in future air quality management in order to mitigate future climate change impacts on air quality.

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This paper discusses how urban freight activity can function such that it meets the urban sustainability objectives policy makers are now beginning to implement. It considers: the importance of urban freight transport in maintaining the economic vitality of the city; the negative impacts that it imposes; the concept of urban sustainability and the development of sustainability strategies; and the means and measures by which freight transport could be made more sustainable. It presents results from a project that investigated the current freight transport operations of seven different companies in three urban areas in the UK. The potential operational, financial and environmental effects of four policy measures on these operations are considered.