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1.
The U.S. Clean Water Act requires compensatory mitigation for wetland and stream damage through restoration of damaged aquatic ecosystems. We evaluate the North Carolina’s Ecosystem Enhancement Program (EEP), a state agency responsible for compensatory mitigation. We compare communities gaining and losing aquatic resources during mitigation, finding new types of socioeconomic disparities that contradict previous studies of mitigation program behavior. We find average distances between impact and mitigation sites for streams (43.53 km) and wetlands (50.3 km) to be larger in North Carolina than in off-site mitigation programs in other regions previously studied. We also find that aquatic resources in the State are lost from urbanized areas that are more affluent, white, and highly educated, and mitigated at sites in rural areas that are less affluent, less well educated, and have a higher percentage of minorities. We also analyze the relationship between urban growth indicators and EEP accumulation of compensation sites. Growth indicators and long-term population projections are uncorrelated with both projected transportation impacts and advance mitigation acquired by the EEP, suggesting that growth considerations can be more effectively incorporated into the EEP’s planning process. We explore the possibility that spatial mismatches could develop between watersheds that are rapidly growing and those that are gaining mitigation. We make recommendations for ways that regulators incorporate growth indicators into the mitigation planning process.  相似文献   

2.
People's perception of crime and incivilities vary considerably depending on their attitudes towards environmental conditions. This paper investigated the hypothesised relationships between Crime Prevention Through Environmental Design (CPTED), victimisation and fear of crime. The checklist was administered by using on-site observation to measure the CPTED construct followed by a self-administered questionnaire to explore the residents' perceptions of victimisation and fear of crime in their area of residency. In all, 164 respondents from a selected group of residents were involved in this study. The structural equation modelling technique was employed and the results indicate that CPTED is negatively related to victimisation. The model also shows that there is a significant positive direct influence of victimisation on fear of crime. However, no direct significant relationship was found between CPTED and fear of crime, but a negative indirect relationship between CPTED and fear of crime was observed through victimisation.  相似文献   

3.
This study examined what factors best predict residents’ concerns about neighborhood safety. One-hundred and twenty-two participants were selected from a large, Midwestern metropolitan area. All participants lived in high crime areas. Participants completed a 22-item questionnaire that assessed their perceptions of neighborhood safety and vigilance. These items were clustered as: 1) Community care and vigilance, 2) neighborhood safety concerns, 3) physical incivilities, and 4) social incivilities. Police crime data were also used in the analyses. Our findings suggest that aspects of the broken window theory, collective efficacy, and place attachments/territoriality play a role in affecting residents’ concerns about neighborhood safety.  相似文献   

4.
5.
The reduction of CO2 emissions constitutes one of the largest challenges of the current era. Sustainable transportation, and especially cycling, can contribute to the mitigation of CO2 emissions since cycling possesses an intrinsic zero‐emission value. Few studies have been conducted that appraise the CO2 reduction potential of cycling. Opportunity costs enable the estimation of avoided CO2 emissions resulting from bicycle trips. The methodology developed in this research allows the attribution of a climate value to cycling by substituting bicycle trips with their most likely alternative transportation modes and calculating the resulting additional CO2 emissions. The methodology uses data on the current modal shares of cycling mobility, the competition of cycling with other transportation modes, and CO2 emission factors to calculate the climate value of cycling. When it is assumed that the avoided CO2 emissions of cycling mobility could be traded on financial carbon markets, the climate value of cycling represents a monetary value. Application of the methodology to the case of Bogotá, Colombia — a city with a current bicycle modal share of 3.3% on a total of 10 million daily trips — results in a climate value of cycling of 55,115 tons of CO2 per year, corresponding to an economic value of between 1 and 7 million US dollars when traded on the carbon market.  相似文献   

6.
Traditionally solid waste management has evolved as mainly the removal of municipal wastes by hauling them out of the city boundaries and dumping them ‘there’. This is in conformity with the ‘out of sight out of mind’ philosophy. However, with the ever increasing tonnage of refuse due to the expansion of urban centers, which implies increased collection, transportation and disposal costs, recycling is currently accepted as a sustainable approach to solid waste management. This paper reports on the findings of a study, conducted in the city of Dar es Salaam between the years 1993 and 1995, on the scavenging activities and recycling trends of some selected items in Dar es Salaam. Apart from the discussions on existing solid waste generation rates (2000 tonnes/day), composition (60% being organic/or vegetable matter) and their management in Dar es Salaam, the paper also presents data obtained through a survey of Vingunguti dump site and other waste collection centers. It was established that there are currently about 600 solid waste scavengers in Dar es Salaam, approximately 109 of whom operate at Vingunguti dump site and others at 14 different collection centers. Many of them opted for scavenging due to unemployment. The study findings indicate that their average monthly income exceeded the official minimum wage (at the time of study) enabling them to support their families. This demonstrates the potential of recycling to generate gainful employment with implied lower crime rates among the unemployed. Recycling activities in the city were observed to be not only a critical source of raw materials for small-scale industries, in the absence of which they would cease to operate, but also a widely accepted environmentally friendly technology for solid waste management. Out of 294 tonnes of studied waste materials (paper, metal, plastic, glass and textiles) only 4 tonnes are recovered and recycled. The remaining 290 tonnes/day of recyclable material are left to pollute the environment or are collected and transported for final disposal and, therefore, unnecessarily contribute to the shortening of the life span of the dump site. Finally, the paper gives some recommendations for improved recycling activity so as to make it an important means of reducing the overall volume of waste materials to be transported and deposited in the dump site and at the same time provide a potential opportunity for employment for unskilled workers.  相似文献   

7.
ABSTRACT

Addressing urban sustainability challenges requires changes in the way systems of provision and services are designed, organised and delivered. In this context, two promising phenomena have gained interest from the academia, the public sector and the media: “smart cities” and “urban sharing”. Smart cities rely on the extensive use of information and communications technology (ICT) to increase efficiencies in urban areas, while urban sharing builds on the collaborative use of idling resources enabled by ICT in densely populated cities. The concepts have many similar features and share common goals, yet cities with smart city agendas often fail to take a stance on urban sharing. Thus, its potentials are going largely unnoticed by local governments. This article addresses this issue by exploring cases of London and Berlin – two ICT-dense cities with clearly articulated smart city agendas and an abundance of sharing platforms. Drawing on urban governance literature, we develop a conceptual framework that specifies the roles that cities assume when governing urban sharing: city as regulator, city as provider, city as enabler and city as consumer. We find that both cities indirectly support urban sharing through smart agenda programmes, which aim to facilitate ICT-enabled technical innovation and emergence of start-ups. However, programmes, strategies, support schemes and regulations aimed directly at urban sharing initiatives are few. We also find that Berlin is sceptical towards urban sharing organisations, while London took more of a collaborative approach. Implications for policy-makers are discussed in the end.  相似文献   

8.
Perceived safety from crime in the urban environment   总被引:1,自引:0,他引:1  
Two studies were conducted to test various aspects of Appleton's Prospect-Refuge Theory. Hypotheses derived from the theory predicted that observers would rate how safe from crime they would feel in specific urban environments on the basis of whether the environments offered visibility (light), prospect (open spaces) and unambiguous refuge (a place where a criminal would not see the intended victim, or where other, non-threatening people were likely to to be present). It was further hypothesized that women in general would feel less safe from crime than men. In Study 1, University students generated lists of environmental features relevant to safety. Light was the most frequently mentioned factor, followed by open space and unambiguous refuge. In Study 2, slides were presented in which these three characteristics were independently varied. The results supported all of the hypotheses.  相似文献   

9.
Is Amsterdam the “ideal city?” Many of the social, economic, and environmental problems facing Amsterdam are considerably less than those in cities in the USA, and in most cases, Western Europe. Amsterdam, at this moment in history, might be the world's greatest city because of its ability to ensure basic necessities, freedom, and creativity. Tolerance of drugs, sexual freedom, along with the integration of different races helps reduce many of the “social problems” faced by most cities. We have compared, on a per capita basis, differences between Amsterdam/Holland and the USA. The Netherlands is a tiny country, and comparisons are made on a city and per capita numbers at the national level. Our data show that Amsterdam has lower crime, murder, rape, drug usage (cocaine, marijuana), teenage pregnancy, diabetes, obesity, suicide, abortion rates, infant mortality, dependence on fossil fuels, and homelessness, and racial segregation is considerably less. People live longer because of Amsterdam's walkability and bike usage and access to parks. Indeed, the Netherlands leads both Western European and the USA in the proportion of trips made walking and bicycling, with significantly reduced car dependency. Ghettos are nearly non-existent compared with the segregation in the 1940s/1950s. Quality housing is supplied to everyone that gives pride of place compared with the stark, cold, and institutional “projects” provided by the US federal government. Amsterdam leads Western Europe by 35% in social housing, compared with runner-up UK, which has significantly less. The modernism of the 1960s where the poor were warehoused is nearly all gone. People living in Amsterdam seem more tolerant, secure, happier, and healthier compared with citizens in the USA. Great cities provide opportunities for all citizens to enhance their lives and ensure an unrivalled level of freedom. We demonstrate that social and environmental justice are tied together. Amsterdam is by no means perfect, but in comparison with many other democratic industrial cities, it is a far better place for citizens of all races, religions, and incomes.  相似文献   

10.
Walking is an important source of outdoor physical activity among elderly people. In order to devise measures aimed at encouraging walking among the elderly it is important to understand how the local environment influences the walking behaviour of elderly people. Here, a model describing the influence of environmental street characteristics on the walking route choice of elderly people is presented. Techniques adapted from the field of transportation research were employed within the model. Data concerning the walking route choice to specific destinations reported by 364 independently living elderly residents (55–80 years) from three Dutch urban districts were collected. Route choice was modelled within a ‘Geographic Information System’ (GIS) database by using ‘resistance factors’ to describe the resistance to walking of street sections (i.e. links) within the street network. These factors were optimized by minimizing the difference between the estimated and the reported number of trips along each link. This is, to the authors' knowledge the first time that this technique has been applied within this context. The influence of link characteristics on link resistance was investigated by multivariate linear regression. The first results of the route choice model and the influence of street characteristics on route choice are reported and discussed.  相似文献   

11.
A majority of North Americans hopes to grow old in the suburbs. This aspiration depends upon their ability to drive and their access to a car. Because it is essential for everyday travel, car-mobility in the suburbs is becoming a symbolic goal. The meanings of mobility for elderly will evolve over time, notably as a result of changes in autonomy. However, the mobility of older adults is mainly understood in terms of daily trips. Little research has considered the temporal dimension of aging as an evolving process. This study aimed at understanding with a qualitative and longitudinal perspective how older people stay (auto-)mobile in their house and their neighborhood against the need to adapt to reduced autonomy and mobility over time. A group of 22 suburbanites aged from 62 to 89 was interviewed in 1999 and in 2006. The results show that even if older people succeed in increasing their mobility, they are headed for inevitable immobility. Among the environmental adaptation strategies that were observed, the constructed behaviors, the dependencies demanding additional supports as well as the social life modulate different evolving experiences of the city: the shrinking city, the fragmented city, and the city by proxy. The built environment is at the heart of a complex process in which the adaptation of mobility contributes to the emergence of new residential experiences.  相似文献   

12.
The energy, environmental and social benefits of sustainable transportation, i.e. public transit, biking and walking, have long been recognized but are now mainstream in global and local transportation policy debates. However, the economic value of sustainable transportation has always been seen as secondary, unless many external costs were included. The results of a new global study show that cities with significant sustainable transportation systems have reduced costs on road construction and maintenance; better operating cost recovery and fuel-efficiency; fewer road accidents and less air pollution. In overall terms, the percentage of city funds going to transportation is reduced. The data show that cities with the most roads have the highest transportation costs and the most rail-oriented cities have the lowest. Further, the most sprawling cities have the highest direct and indirect costs for transportation. Thus, strategies to contain sprawl, to reurbanize, to build new rail systems into car-dependent suburbs with focussed sub-centers, and to facilitate biking and walking, not only will improve energy efficiency but will reduce costs to the economy of a city. Strategies that build freeways and add to sprawl will do the opposite. Trends indicate that moves toward sustainable urban patterns are beginning. The need to operationalize sustainable transportation strategies in planning and engineering practice and in the politics of infrastructure funding remains a major challenge. Some cities are showing how this can be done.  相似文献   

13.
In the mineral rich but arid Pilbara region of Western Australia, managing water constraints represents a significant challenge to the mining sector where local depletion is a growing problem. Conversely, the expansion of pit dewatering is creating surface water excess in localised areas of potentially high social and ecological significance. Indigenous people are by far the longest term residents of the Pilbara region and express a range of strong concerns about past, current and future water-related developments in the area. They also have proprietary interests in water recognised by the common law and protected by federal native title legislation. Rio Tinto Iron Ore (RTIO), commissioned the authors to undertake research to improve corporate understanding of Indigenous interests in water and to provide advice on its consultation processes. We argue here that a more sophisticated account of Indigenous water values is a necessary but, on its own, insufficient measure to achieve RTIO’s desired long-term goals. We suggest an equivalent process of understanding and documenting corporate water values and interests, actions to improve trust and credibility in the relationship between the parties, and leadership in wider catchment management as necessary complementary actions. These actions follow logically from internal corporate commitments regarding water and Indigenous people and from recognition of their property rights, but also align directly with major trends in the National Water Initiative, the key water policy framework for Australia. Therefore significant synergies exist between internal corporate aspirations, the evolving legal regime, and wider governance agendas for a key limiting resource. Our analysis is relevant to a range of CSR and water resource contexts across the wider mining sector.  相似文献   

14.
The management of urban transportation systems represents one of the most formidable challenges for local government that generates several problems related to the well-being and the comfort of the public that commute and travel in their daily life. Improvements to various policies and practical measures can move us closer to the ideal of sustainable urban areas with sustainable urban transportation systems. Nevertheless, these aspirations in no way ensure unanimity over the most effective actions to take and the extent of their benefits. In response, a mathematical model has been developed for decision-taking purposes using multi-criteria analysis adapted to urban transportation systems. This model not only takes account of environmental parameters, but also examines economic, social and urban models, the characteristics and condition of the transport fleet and freight distribution vehicles, in order to generate a sustainability index value for the transportation system of urban areas.  相似文献   

15.
Despite the fact that virtual environments are increasingly deployed to study the relation between urban planning, physical and social disorder, and fear of crime, their ecological validity for this type of research has not been established. This study compares the effects of similar signs of public disorder (litter, warning signs, cameras, signs of vandalism and car burglary) in an urban neighborhood and in its virtual counterpart on the subjective perception of safety and livability of the neighborhood. Participants made a walking tour through either the real or the virtual neighborhood, which was either in an orderly (baseline) state or adorned with numerous signs of public disorder. During their tour they reported the signs of disorder they noticed and the degree to which each of these affected their emotional state and feelings of personal safety. After finishing their tour they appraised the perceived safety and livability of the environment. Both in the real and in the simulated urban neighborhood, signs of disorder evoked associations with social disorder. In all conditions, neglected greenery was spontaneously reported as a sign of disorder. Disorder did not inspire concern for personal safety in reality and in the virtual environment with a realistic soundscape. However, in the absence of sound disorder compromised perceived personal safety in the virtual environment. Signs of disorder were associated with negative emotions more frequently in the virtual environment than in its real-world counterpart, particularly in the absence of sound. Also, signs of disorder degraded the perceived livability of the virtual, but not of the real neighborhood. Hence, it appears that people focus more on details in a virtual environment than in reality. We conclude that both a correction for this focusing effect and realistic soundscapes are required to make virtual environments an appropriate medium for both etiological (e.g. the effects of signs of disorder on fear of crime) and intervention (e.g. CPTED) research.  相似文献   

16.
ABSTRACT: In this paper a numerical model for flood propagation in urban areas is proposed. It has been applied to evaluate flooding hydraulic characteristics in terms of potential flood elevations, depths, and inundated areas. Furthermore, the algorithm efficiency and the consequent reduced computation time allow the use of the hydraulic model as a part of a more complex system for civil protection actions, planning, and management. During flood events, the transportation network plays a main role both in rescuing people when they are more vulnerable and in moving people and materials from and toward affected areas. The reduced efficiency of this transportation network is evaluated based on a least‐flood‐risk path‐finding algorithm. The results of a case study concerning the northern part of the city of Rome, show that the numerical model for unsteady flow in open channel networks achieves the proposed aims. It has proven to be able to describe the flood hydraulic characteristics and to be suitable for real‐time flood emergency management in urban areas.  相似文献   

17.
We use spatial data representing transportation networks, elevation, stand height, and recreation use to construct and compare models of recreation use patterns and visibility in a forest. The recreation use pattern model depicts use frequencies along travel corridors. The visibility model quantifies visibility for all forest areas. We find that the models provide different but complementary types of information. Forest managers who are involved in scheduling harvest operations and want to address the visual concerns of forest visitors may benefit most from the visibility model. Managers who wish to know more about travel patterns or to reroute forest visitors affected by operations may benefit from the use pattern model. A combination of the two models has the highest potential for providing planning assistance in multiple-use forests. Both models may be able to enhance visual resource management (VRM) systems already in use by providing spatially explicit recreation use and visibility data.  相似文献   

18.
Spatial criminology has three interrelated elements: place, distance, and direction. Though directionality has had theoretical support for many years, very few empirical verifications of this component of crime have emerged. In this article, we investigate the strength of directionality by comparing a simulated randomized dataset and a large incident-based dataset of repeat offenders. We find strong evidence for a strong presence of directionality in criminal spatial decision-making. This aspect of the spatiality of crime must be considered in any attempts to understand the aetiology of crime.  相似文献   

19.
Among policy-makers and governments, there is a broad consensus that artisanal and small-scale mining (ASM) needs to be ‘formalized’ – embodied in a standardized legal framework that is registered in and governed by a central state system-, the basic condition being that artisanal miners are given formal property rights. This article aims to contribute to this discussion, drawing on a case study from the Eastern Democratic Republic of Congo (DRC), where it is estimated that up to 90 percent of mineral production and export is ‘informal’. After having pointed out some of the theoretical assumptions behind the formalization canon, we study the challenges of formalizing the mining sector in the DRC. Next, we provide an in-depth analysis of one concrete policy measure of the Congolese government, the temporary ban on all artisanal activities. We argue that the mining ban was not only a radical example of a top-down formalization policy, but also an illustration of a bureaucratic and technical measure that compounds but does not address different problems associated with ASM: conflict, informality, poverty, illegality, state control. Looking at the empirical evidence from the DRC, we argue that these kinds of technical solutions can never address the broader socio-economic and political issues at stake.  相似文献   

20.
The cause of poor welfare in broilers is multifactorial, but genotype is a major contributor. Modern broilers have been bred for rapid growth, and this leads to increases in lameness and ascites as the legs and hearts of the heavier birds find it difficult to cope with the extra demands placed on them. Visible lameness indicative of pain is more common in New Zealand than in Europe. The government, however, insists that New Zealand welfare standards are higher than Europe. The government also appears to have a strong antipathy to those demanding better welfare for broilers. Reasons for this antipathy and disparities between government statements and research results are discussed. Government publications reveal that animal welfare is seen as a question of image for market access and that there is little concern with animal welfare as an ethical imperative for its own sake. The Animal Welfare Act in theory makes it an offence to ill treat an animal, but in practice allows exemptions for industrial agriculture. The interests of animals may be better protected by an independent animal welfare advisory service.  相似文献   

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