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101.
This paper applies a spatial perspective to environmental problems in search for the paths to sustainability, using polluting plant relocation in China as a case study. It examines how environmental improvement in one place may lead to environmental degradation in another place, how geographic concepts such as location, distance, spread and backwash effects, and land use models can help understand such phenomenon, and what the implications are for the environmental Kuznets curve (EKC) and development policies. Field research was conducted from 2006 to 2012 in Chinese cities of Beijing, Dalian, Shanghai, Guangzhou, Wuxi, Hangzhou, and Ningbo. It involved intensive site observations and in-depth interviews with government officials of environmental protection, economic development, and business recruitment, and grassroots environmentalists. The results indicate that environmental improvement in all these cities has led to environmental degradation in their suburbs and rural areas due to relocation of polluting plants. Environmental spread and backwash effects may help explain the severe intra-regional environmental and economic disparities and environmental injustice. The powerful and wealthy may achieve rapid economic growth and environmental recovery at the expenses of the powerless and poor, leading to environmental poverty and sustainability disparities.  相似文献   
102.
Local government has a key role to play in implementing sustainability. Yet even councils attempting to address the issue of sustainability are often unacceptably slow and ineffective in their endeavours. This study investigates the approaches that councils currently take in implementing sustainability, as this may shed additional light on the slow progress of councils towards sustainability. The approaches of three New South Wales councils were examined and assessed using a model developed for the study that utilised the Ecological Footprint as the primary assessment tool. The model assessed three key aspects of council approaches to implementing sustainability: (1) the issues councils target for change; (2) the methods councils use to change behaviours; and (3) the clarity and holistic nature of their approaches. All three council approaches scored poorly against the model mainly as a result of the councils' failure to target the behaviours of their residents that are causing the greatest ecological harm. The major implication is that councils need to reconsider, and possibly overhaul, their approaches to implementing sustainability as these approaches are unlikely ever to achieve sustainability.  相似文献   
103.
Up to one-third of commercial fishery stocks may be overfished at present. By analyzing catch trends and applying an empirical relationship derived from stock assessments, this article tracks the geographic spread of overfishing at the country level in terms of lost catch and lost revenue, from the start of industrialized fishing in 1950-2004. The results tell a cautionary tale of serial depletion to meet the ever-rising demand for fish. Examining country losses with respect to fishery management reveals that overcapacity and excess fishing effort are widespread, but also that recent trends towards sustainability can stabilize or reverse losses (e.g. for Norway, Iceland, the US, Canada, Australia, and New Zealand). Global trade effectively masks the successive depletion of stocks, so that without decisive action to reduce fishing effort, many more stocks will suffer and undernourishment impacts for the major exporting, food-deficit nations will only magnify.  相似文献   
104.
The objective of this paper is to create the Global Seafood Market Performance Index (GSMPI) in order to compare fisheries-related impacts of different countries across spatial and temporal scales. The article presents the first effort to investigate the trade-offs among marine ecosystems, seafood markets, poverty alleviation, food security and governance at worldwide level by creating the GSMPI. The GSMPI will provide relevant information on environmental, governance, socioeconomic, food security, corruption, seafood market, and corporate social responsibility issues for individual decision-makers and scientists, national governments, and stakeholders as well as international fishing and aquaculture industries.  相似文献   
105.
106.
The development and use of indicators is common practice in efforts to promote urban sustainability. Indicators used to measure urban sustainability tend to focus narrowly on describing the current state of the urban system. Although a time series analysis using these indicators may lend insights into trends towards or away from certain ‘sustainability’ goals, existing indicators of urban sustainability do not provide information on the ability or the likelihood that the current system state can be maintained or improved over time. Indicators that incorporate a measure of system resilience would provide useful information on system sustainability. Through development of a new indicator, Water Provision Resilience (WPR), we provide an example of how measures of resilience could be incorporated into sustainability indicators. The new indicator adds six color codings to the existing indicator ‘percent of the population with access to safe water.’ Each color coding represents a measure of the ability of the water system to maintain or improve the current percent of the population with access to safe water in key areas of the water provision sector: supply, infrastructure, service provision, finances, water quality and governance. The metric is then applied to three cities. The goal in developing this metric is to provide a starting point for re-thinking the metrics used to measure progress and sustainability in order to incorporate the ability to absorb and adapt to stresses into sustainability analysis.  相似文献   
107.
Stakeholders’ perceptions can influence the success of a fishery. It is important to take these perceptions into account when evaluating the development of a management system and its conservation policies. Structured questionnaires were used to determine fishers’ management and conservation perceptions of the Asturian gooseneck barnacle co-management system. Perceptions were analyzed for the entire fishery and for different socioeconomic factors, these were: location, age, years in the management system, way of access, alternative income sources and income. Fishers’ perceptions varied widely among socioeconomic factors. In fact, a trade-off between management and conservation perceptions was observed for the different categories within each socioeconomic factor, particularly for the years in the management system, location and income factors. Despite the heterogeneity in perceptions, the co-management system has successfully generated a strong conservation ethic in its resource users. Furthermore, as a group, gooseneck barnacle fishers hold positive perceptions on the performance of the management system. When generating management policies, fisheries’ managers must take the heterogeneity of resource users present in the fishery into account. The gooseneck barnacle co-management system demonstrates that even within the same fishery there can be multiple paths to sustainability.  相似文献   
108.
109.
This article draws on a serial interview study of later life leisure travel in the UK to question how a wider trend towards holidaying further afield has come to feature in the lives of three cohorts of older Britons. Drawing on theories of social practice that see notions of desirable activity as produced through the interplay of opportunities to engage in relevant activities, collective apprehensions of what doing these activities should involve, and the physical capacities necessarily required to undertake them, we examine their leisure travel in two regards. Firstly, we consider how evolving social and infrastructural arrangements are effectively demanding greater distance travel in the sense that they shape what socially desirable leisure travel is taken to entail at certain points in time. Secondly, we examine how distance travel may be physically demanding in the sense that older bodies may be particularly likely to face certain challenges when they travel. This strategy allows us to examine how broader social expectations regarding distance travel have become part of the lives of older Britons and the manner in which they are currently reconciling them with both the anticipation and the experience of bodily ageing. We end with the implications of our findings for the future of later life leisure travel as a potential hotspot of growing societal energy demand and the further application of social practice theory in view of the evidently variable capacities of human bodies.  相似文献   
110.
Containment landfills: the myth of sustainability   总被引:5,自引:0,他引:5  
A. Allen   《Engineering Geology》2001,60(1-4):3-19
A number of major problems associated with the containment approach to landfill management are highlighted. The fundamental flaw in the strategy is that dry entombment of waste inhibits its degradation, so prolonging the activity of the waste and delaying, possibly for several decades, its stabilisation to an inert state. This, coupled with uncertainties as to the long-term durability of synthetic lining systems, increases the potential, for liner failure at some stage in the future whilst the waste is still active, leading to groundwater pollution by landfill leachate. Clay liners also pose problems as the smectite components of bentonite liners are subject to chemical interaction with landfill leachate, leading to a reduction in their swelling capacity and increase in hydraulic conductivity. Thus, their ability to perform a containment role diminishes with time. More critically, if diffusion rather than advection is the dominant contaminant migration mechanism, then no liner will be completely impermeable to pollutants and the containment strategy becomes untenable.

There are other less obvious problems with the containment strategy. One is the tendency to place total reliance on artificial lining systems and pay little attention to local geological/hydrogeological conditions during selection of landfill sites. Based on the attitude that any site can be engineered for landfilling and that complete protection of groundwater can be effected by lining systems, negative geological characteristics of sites are being ignored. Furthermore, excessive costs in construction and operation of containment landfills necessitate that they are large scale operations (superdumps), with associated transfer facilities and transport costs, all of which add to overall waste management costs. Taken together with unpredictable post-closure maintenance and monitoring costs, possibly over several decades, the economics of the containment strategy becomes unsustainable. Such a high-cost, high-technology approach to landfill leachate management is generally beyond the financial and technological resources of the less wealthy nations, and places severe burdens on their economies. For instance, in third world countries with limited water resources, the need to preserve groundwater quality is paramount, so expensive containment strategies are adopted in the belief that they offer greatest protection to groundwater. A final indictment of the containment strategy is that in delaying degradation of waste, the present generations waste problems will be left for future generations to deal with.

More cost-effective landfill management strategies take advantage of the natural hydrogeological characteristics and attenuation properties of the subsurface. The ‘dilute and disperse’ strategy employs the natural sorption and ion exchange properties of clay minerals, and it has been shown that in appropriate situations it is effective in attenuating landfill leachate and preventing pollution of water resources. Operated at sites with thick clay overburden sequences, using a permeable cap to maximise rainfall infiltration and a leachate collection system to control leachate migration, ‘dilute and disperse’ is a viable leachate management strategy. Hydraulic traps are relatively common hydrogeological situations where groundwater flow is towards the landfill, so effectively suppressing outwards advective flow of leachate. This approach is also best employed with a clay liner, taking advantage of the attenuation properties of clays to combat diffusive flow of contaminants. These strategies are likely to guarantee greater protection of groundwater in the long term.  相似文献   

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