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41.
The paper examines changing approaches to local economic development in the period since 1974. Initially, it proposes an ‘orthodox’ model of local economic development policies which emphasised the provision of a better industrial fabric, and of financial assistance to small, inner city firms. It suggests three recent directions of change in emphasis from this orthodox model: help in the creation of new entrepreneurs; replacement of public sector by private sector action; local authority shareholding in local firms by use of Enterprise Boards. Each approach makes different assumptions about the public/private sector relationship, the last two involve a more explicitly ideological stance on this issue.  相似文献   
42.
ABSTRACT: The regulatory process such as that for water rates can be viewed as a bargaining process between regulators, utility management, and consumers. This bargaining process involves both political and economic influences. In an attempt to empirically verify that utility rates are a product of both economic and political factors, a sample of publicly-owned water utilities was subjected to regression analysis. As expected, cost and cost-related factors were positive and significant determinants of residential water rates. Using an admittedly imperfect measure of residential user political influence, there was evidence that increased political activity results in lower water rates. Furthermore, the political influence and water rate linkage is more evident in small water utilities than in larger suppliers.  相似文献   
43.
ABSTRACT

City strategic plans and enabling policies provide a framework for and inform future development across multiple scales. An exemplar city strategic plan will be one based on evidence, enabled by complementary policy outcomes, and built on the knowledge of the existing landscape. This study evaluated the plan quality of eighteen metropolitan strategic plans for city members in the 100 Resilient Cities initiative. A protocol was developed containing thirty-two indicators to assess plans capacity to act as a strategic planning tool to develop, analyse and implement strategies for the Urban Heat Island (UHI) and climate change mitigation and adaptation. The evaluation indicated that strategies addressing the UHI are rarely included in metropolitan plans. Strategic plans showed a lack of evidence-base to inform the potential actions. Urban warming is often linked to extreme weather events anticipated under climate change, not the UHI as a systemic and increasing phenomenon. We recommend that the pathway to addressing UHI mitigation and adaptation may lie in its nexus to aspects of climate change that concurrently can serve to support liveable and resilient cities.  相似文献   
44.
ABSTRACT: A comprehensive mathematical model (Urban Wastewater Management Model) has been developed to continuously simulate time-varying wastewater flows and qualities in complex metropolitan combined sewerage systems. The model serves three functions: (1) assessment of existing or planned system performance in relation to other wastewater discharges in either a metropolitan or river basin area; (2) determination of the optium operation or automatic control of existing or planned systems during rainstorms; and (3) determination of the most economically feasible combination of design alternatives for improving or expanding existing systems to meet specified performance criteria. The model provides an efficient engineering tool for evaluating and controlling pollutant discharges from combined sewerage systems (including treatment plants) to receiving waters, while considering the time and spacial variations of rainfall and dry-weather flows and qualities as well as economic constraints.  相似文献   
45.
Understanding the magnitude and location of soil phosphorus (P) accumulation in watersheds is a critical step toward managing runoff of this pollutant to aquatic ecosystems. Here, I examine the usefulness of urban–rural gradients, an emerging experimental design in urban ecology, for predicting extractable soil P concentrations across a rapidly urbanizing agricultural watershed in southern Wisconsin. I compare several measures of an urban–rural gradient to predictors of soil P such as soil type, slope, topography, land use, land cover, and fertilizer and manure use. Most of the factors that were expected to drive differences in soil P concentrations were found to be poor predictors of Bray-1 (extractable) soil P, which ranged from 4 to 660 ppm; while there were several significant relationships, most explained only a small proportion of the variation. A multiple linear regression model captured approximately 37% of the variation in the data using the urban–rural gradient, topography, land use, land cover, manure use, and soil type as predictors. There was a significant relationship between Bray-1 P concentration and each of the urban–rural gradients, but these relationships explained only between 2.6% and 3.3% of the variation in P concentrations. Extractable P concentration in soils, unlike some other ecosystem properties, is not well predicted by urban–rural gradients.  相似文献   
46.
Contemporary urban planning is characterised by the following: (a) a large amount of specific research gives a large quantity of facts, but like stones of the mosaic do hot make an entire picture; (b) in the basis of these researches no one finds entire creative conceptions; (c) the theories lose touch with practical design matter; (d) in contradiction to the classical architectural epoch, urban planning loses touch with the construction of buildings; (e) the practice of urban planning and the construction of buildings lose touch with historical traditions. The corollary of these academic and unnatural specialisations is a break not only from “the tie of times” but also from the ties inside the profession. This situation has an effect on the practice of urban planning and architecture; society returns to destructive criticism. It is impossible to get away from this fact. The author makes an attempt to change this situation for the better — at least in some measures. On the basis of many years study of the results of research this paper presents a concept of contemporary urban planning. This concept is not in the form of hard recommendations, but expedient methods for the solution of problems. It is proved by the author's projects.  相似文献   
47.
Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.  相似文献   
48.
Recent research has highlighted the positive role of green areas in urban environments, providing numerous social, environmental and economic services, such as mitigation of the urban heat island effect, storm attenuation, increased water infiltration into the soil, reduction of noise and air pollution, among others. However, the maintenance of green areas may result in high consumption of water, reaching 50% of the total consumption in some municipalities, and energy, becoming a reason of concern. The present study aimed to integrate techniques and technologies that promote the automatic and efficient irrigation of urban landscapes, using alternative sources of energy and water, toward its sustainability. The conceptual unit was able to reduce in 64% the water consumed in irrigation. Rainwater met 69% of the demand and the photovoltaic system supplied all the energy required. The economic feasibility analysis showed that the conceptual unit is financially unfeasible, under the conditions of this study. However, with some interventions for reusing the surplus energy and water, and considering the higher fees charged by other cities, the investment became attractive. In this new scenario, the internal rate of return (15 years) was 27.3% and the discounted payback period was 4.9 years.  相似文献   
49.
The hydrocarbon compositions of atmospheric particulate matter from urban areas of Rio de Janeiro city have been studied to assess the different pollution levels. Samples were acquired using a standard high-volume air sampler (Hi-Vol), extracts were prepared and fractionated into aliphatic and aromatic compounds. High-resolution gas chromatography and GC coupled to mass spectrometry (GC–MS) were used for the analysis of the organic matter. The results show that all samples contain n-alkanes, but the distributions are different for each sample, reflecting both the biogenic (vascular plant wax input) and fossil fuel contamination sources (vehicular exhaust). The fossil fuel biomarkers, hopanes and steranes, were also observed in all samples except in the Tijuca Forest, which is a mountain forest in the midst of the sea-level city. A decrease in the level of pollution was observed in the sequence for Rebouças Tunnel>Cinelândia (downtown)>Quinta da Boa Vista Park>Tijuca Forest, as expected from the traffic density. Unfortunately, all sites are polluted mainly from vehicular emissions, but at different degrees, with the lowest levels in Tijuca Forest.  相似文献   
50.
Feral pigeons are descendants of wild rock pigeons that have adapted to the urban habitat. They have partially conserved the foraging behaviour of their wild ancestors (flights to agricultural areas) but have also developed new habits. Previous studies on the foraging strategies of feral pigeons have given various results, e.g. maximum distances reached by the pigeons (measured in a straight line from the resting places) differed between 0.3–0.5 km and 18–25 km. This study focuses on the spatio-temporal activity of feral pigeons in the urban habitat. We equipped 80 free-living feral pigeons from Basel, Switzerland with GPS receivers. We found three different foraging strategies for pigeons in Basel: (1) in the streets, squares and parks near the home loft, (2) in agricultural areas surrounding the city, (3) on docks and railway lines in harbours. The maximum distance reached by a pigeon was 5.29 km. More than 32% of the pigeons remained within 0.3 km of the home lofts and only 7.5% flew distances of more than 2 km. Females covered significantly longer distances than males, preferring to fly to more abundant and predictable food sources. Temporal activity patterns showed to be influenced by sex, breeding state and season. In contrast to wild rock pigeons and to feral pigeons in other cities, pigeons in Basel showed a clear bimodal activity pattern for breeding birds only. The differences between our results and those of other studies seem to be partly method-dependent, as the GPS-technique allows to record the pigeons’ localisations continuously in contrast to other methods. Other differences might be due to different kinds of food supply in the various cities. Our study shows that feral pigeons have individual foraging strategies and are flexible enough to adapt to different urban environments.Electronic supplementary material Supplementary material is available for this article at  相似文献   
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