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1.
The decontamination of soils and wastes polluted with heavy metals presents one of the most intractable problems for soil clean-up. Present technology relies upon metal extraction or immobilization processes, both of which are expensive and which remove all biological activity in the soil during decontamination. They may only be appropriate for small areas of valuable redevelopment land. In this paper the use of metal-accumulating plants is explored for the removal of metals from superficially-contaminated soils such as those resulting from the long-term application to land of metal-contaminated sewage sludges. Green remediation employs plants native to metalliferous soils with a capacity to bioaccumulate metals such as zinc and nickel to concentrations greater than 2% in the aerial plant dry matter (hyperaccumulators). Growing such plants under intensive crop conditions and harvesting the dry matter is proposed as a possible method of metal removal and for ‘polishing’ contaminated agricultural soils down to metal concentrations below statutory limits. Not only are the biological activity and physical structure of soils maintained but the technique is potentially cheap, visually unobtrusive and offers the possibility of biorecovery of metals. The limitations of the process are reviewed and the future requirements for the development of efficient phytoremediators are outlined.  相似文献   

2.
An analysis of the long-term demands, supplies and costs for phosphorus is employed as an example of ‘worst case’ research. Worst case research attempts to bound the problems posed in The Limits to Growth relating to running out of minerals and other raw materials by studying the costs of obtaining such materials from some vast source such as common rock. Since the costs of extracting minerals from these near infinite sources are as high as they would go for thousands of years, they represent the upper limit or worst case outlook, especially since the estimated costs are based on current technology. Recycling, conservation and other possibilities are also examined. At least in certain cases it may be possible from such research to make clearer judgements about the questions of exhaustion posed by the ’limits to growth’ literature.  相似文献   

3.
The ‘Clark Phenomenon’ began in 1966 with two major events: the publication of a special number of the Journal of Social Issues with the (now admittedly sexist) title of ‘Man's Response to the Physical Environment’, and the arrival of Jim Blaut on campus. This watershed year, just two decades ago, also may have marked the transition from infancy to adolescence of the reborn field of ‘environmental cognition’. This article traces these early middle years of environmental cognition and its related emphases at Clark, the leadership of certain members of the faculty of the Graduate School of Geography in bringing the new field to full flower, the spinoffs and inevitable reactive forces, and the application of environmental cognition to problems of intercultural communication on environmental issues of an international scope. Such application is a later reflection of the social and political consciousness of the 1960s, the concern to relate environmental psychology to what was taking place in the U.S.A. and in the ‘emerging’ nations of the so-called developing world. In all of this, the Clark influence was, and remains, relevant.  相似文献   

4.
The provision of green space is increasingly being perceived as an important factor for quality of life. However, green spaces often face high developmental pressure. The main objective of this study is to investigate a prospective approach to green space planning by combining three-dimensional (3D) visualization of green space scenarios and survey techniques to facilitate improved participation of the public. Aside from the ‘Status quo’, scenarios ‘Agriculture’, ‘Recreation’, ‘Nature conservation’ and ‘Wind turbines’ are visualized in three dimensions. In order to test responses, a survey was conducted both in print format and on the Internet. Overall, 49 different visualizations that belong to one of the scenarios were available in the survey and were rated according to the perceived esthetic, recreational and ecological values.The highest rated scenes include vegetation elements such as meadows with orchards, single trees, shrubs or forest. The least attractive scenes are those where buildings are highly dominant or where there are no vegetation elements.Based on the ratings for the individual images and on the corresponding scenarios, our study shows that there is high potential for improving the existing landscape. All suggested changes are either rated about equal to or considerably higher than the status quo, with the scenario ‘Nature conservation’ receiving the highest scores.  相似文献   

5.
Research on the relationship between people and nature has rarely incorporated a definition of natural environments. This exploratory project was designed to uncover underlying themes which comprise conceptualization of natural environments. Fourteen interviews were conducted with adult respondents, combining a biographical section with a picture sorting exercise. Content analysis revealed a myriad of dimensions and attributes which can be organized into four meta-level themes used to categorize environments as natural or not natural. The meta-themes included: (1) people as separate from nature; (2) assessment of natural elements; (3) human impact on nature; and (4) the human place within natural environments. Further analysis of the meta-level themes led to hypothesis generation about possible subcategories of natural environments, including ‘totally natural’, ‘civilized natural’, ‘semi-natural’ and ‘quasi-natural’. ‘Non-natural’ environments were also included in this schema, as they define the boundary of natural environments. A kaleidoscope model is used to illustrate how nature is defined through a complex web of interrelationships.  相似文献   

6.
7.
This research examined differences between the features of ‘high’ and ‘popular’ style residential architecture and between responses to those styles by architects and non-architects. Forty slides (20 of each style) were scored in terms of physical properties. They were also rated by 20 architects and 20 non-architects. The research identified distinct physical features of each style. ‘High’ style residential architecture had fewer materials, more concrete, simpler forms, more white, and off-center entrances. They were judged as more complex, novel, and exciting. ‘Popular’ style residential architecture was characterized by use of more building materials, horizontal orientation, hip roofs, framed windows, centered entrances, and warm colors. Architects and non-architects differed in how they characterized and evaluated the two kinds of buildings, Architects rated the ‘high’ buildings as more clear, coherent pleasant, relaxing, and meaningful. Models of preference revealed that both groups favored novelty and coherence (or clarity), but the non-architects favored simplicity and ‘popular’ attributes, while the architects favored complexity and ‘high’ attributes.  相似文献   

8.
The paper presents a novel transdisciplinary approach to investigate non-sustainable civilisation–nature interactions in the context of global change. The approach rests on the decomposition of intricate dynamics of Global Change into problematic patterns civilisation nature interactions (‘syndromes’) this is done by an iterative process of observations, data and theoretical system analysis and GIS-based modelling attempts. These syndromes of global change characterise endangering and risky developments of civilisation nature interaction and represent a baseline for measuring and indicating ‘non-sustainability’; in order to have a sustainable development it is necessary to have a far-reaching absence of syndromes. They encompass the core problems of global change, e.g. soil degradation, climate change, threats to biodiversity or global deforestation. Patterns are defined as characteristic constellations of global change trends (‘symptoms’). Cause–effect schemes of symptoms and their interrelations are constituted as complex phenomena resulting from interactions over the different spheres of the Earth system (biosphere, atmosphere, hydrosphere, population, pedosphere, economy, psychosocial sphere, social organisation, science and technology). The approach is illustrated by an analysis of civilisation–nature interaction patterns relevant for global deforestation. Global forest ecosystems have been chosen for this investigation because of their important role in the global carbon cycle and their importance for biological diversity. The resulting geographical patchwork of the combined dispositions and intensities of the different syndromes describes current and future regional threats to forests by their underlying global cause–effect patterns of civilisation–nature interaction.  相似文献   

9.
With the intention of bridging the ‘digital divide’ many programmes have been launched to provide computers for educational institutions, ranging from refurbishing second hand computers to delivering low cost new computers. The fast and economical provision of large quantities of equipment is one of the many challenges faced by such programmes. If an increase is to be achieved in the sustainability of computer supplies for schools, not only must equipment be provided, but also suitable training and maintenance delivered. Furthermore, appropriate recycling has to be ensured, so that end-of-life equipment can be dealt with properly. This study has evaluated the suitability of three computer supply scenarios to schools in Colombia: (i) ‘Colombian refurbishment’, -refurbishment of computers donated in Colombia, (ii) ‘Overseas refurbishment’, -import of computers which were donated and refurbished abroad, and (iii) ‘XO Laptop’, -purchase of low cost computers manufactured in Korea. The methods applied were: Material Flow Assessment, -to assess the quantities-, Life Cycle Assessment, -to assess the environmental impacts, and the application of the Multiple Attribute Utility Theory, -to analyse, evaluate and compare different scenarios. The most sustainable solution proved to be the local refurbishment of second hand computers of Colombian origin to an appropriate technical standard. The environmental impacts of such practices need to be evaluated carefully, as second hand appliances have to be maintained, require spare parts and sometimes use more energy than newer equipment. Providing schools with second hand computers from overseas and through programmes such as ‘One Laptop Per Child’ has the disadvantage that the potential for social improvements – such as creation of jobs and local industry involvement – is very low.  相似文献   

10.
James L. Hay   《Resources Policy》2009,34(3):142-149
This paper considers liberal and nationalist economic policy approaches to the ownership and development of Australian energy resources (oil, gas, coal and uranium). In the two decades prior to 1983, Australia pursued economic policies in relation to its energy resources which could broadly be described as ‘nationalist’. Governments of the day intervened in development decisions in an effort to enhance the ‘national interest’. From 1983, along with the deregulation of the Australian economy as a whole, policy relating to energy resources was liberalised. Development of energy reserves henceforth occurred according to the dictates of the market. This paper argues that recent Australian energy policy initiatives reflect an increase in nationalist influences and a retreat from the liberalisation agenda that dominated energy policy making in the 1980s and 1990s. Three examples are discussed where policy has been influenced by a nationalist framework: (1) the domestic gas reservation policy in Western Australia; (2) Australian government efforts to promote a ‘value adding’ nuclear processing industry and (3) Australian Labor Party policy giving preferential financial incentives for gas to liquids projects. The re-emergence of nationalism in Australia is occurring either because policy makers now favour it as a path to energy security or in some cases because they believe that appeals to nationalism will generate political support.  相似文献   

11.
The authors highlight the importance of the trippage of a returnable bottle to the current beverage container debate. Results of recent surveys of consumers and retailers are presented, which show that the reasons for low trippages in the UK are more complex than the conventional diagnosis that ‘consumers cannot be bothered to return bottles’. In many instances consumers thought that the ‘returnable bottle was ‘non- returnable’ and many consumers found it difficult to return bottles to the shops. Making it easier for consumers to return the bottle would appear to be a more effective method of raising trippage than increasing the deposit levels.  相似文献   

12.
This paper critically examines pricing policy options for water resources and attempts to derive an operationally feasible and socially desirable pricing structure for this important resource. Marginal cost pricing options are studied under different economic and resource conditions, such as inflation, constrained water resources and price distortions in an economy. Options such as pricing of water at its ‘real’ resource value, ‘social’ pricing, and pricing to reflect intangible benefits are also examined.  相似文献   

13.
The effect of resource rent taxation on mineral exploration is a controversial issue on which very little research has been carried out. Simple numerical examples are used in this paper to demonstrate that a ‘pure’ resource rent tax, or Brown Tax, can reduce the extent of exploration of a ‘promising’ deposit by a risk averse explorer, but encourage exploration of ‘unpromising’ deposits. This counter-intuitive result is explained in terms of the effect of the tax and of exploration on the costs of risk and uncertainty.  相似文献   

14.
This study examined the cognitive effects associated with homesickness. Theoretical explanations of the homesick syndrome suggest a major cognitive component in the form of a loss of concentration as a result of intrusive thoughts of home. Two attentional demand models proposed by Fisher (1989, Homesickness, Cognition and Health. London: Lawrence Erlbaum) are assessed: the ‘demand strength model’ which suggests intensity of homesickness will decrease attentional ability, and the ‘competing demand model’ which suggests degree of commitment to a new environment will be positively related to attentional ability. Students that had relocated to attend university were evaluated for evidence of homesickness using the Dundee Relocation Inventory (Fisher, 1989). Homesick students and relocated students that showed evidence of commitment to their new environment were compared on attentional ability and academic performance. Results suggest that homesickness may reduce ability to concentrate, but that this loss of concentration is not sufficient to cause a marked loss of academic ability.  相似文献   

15.
Changes in agricultural policy have traceable effects on landscape aesthetics. For the catchment area of Lake Greifensee, an economic land-use model predicted land-use changes caused by agricultural policy. Three scenarios implementing different direct payment schemes show that land-use intensity will decrease by 2011 compared with the ‘reference status’ 2000.The output of the economic land-use model is explicit in space. It was assessed by the ‘naturalness’ perception factor of the method proposed by Hoisl et al. [1989. Landschaftsästhetik in der Flurbereinigung. Materialien zur Flurbereinigung—Heft 17. Bayerisches Staatsministerium für Ernährung, Landwirtschaft und Forsten, München] with regard to landscape aesthetics. Even though lower land-use intensity is generally predicted by 2011, the values of the ‘naturalness’ perception factor do not significantly improve if the payment scheme remains unchanged, or if the payment scheme is amended by incentives for specific location of the ecological compensation areas (ECAs). A significant reduction in the values of the ‘naturalness’ perception factor was found when subsidies for ECA's were cancelled. This leads us to the conclusion that in order to keep Swiss landscapes as attractive as they are at present, policy must sustain incentives for low-intensity land-use types.  相似文献   

16.
This research presents the results of a qualitative study of a small sample of older adults (n = 25), age 55+ who have recently moved to an area that is rapidly changing from a tourist community into a retirement community. The study has two main research objectives: (a) to use Oswald and Wahl's heuristic meaning of home framework to explore the relationships between older adults and their homes and communities, integrating theories from environmental psychology, environmental gerontology and human geography, and (b) to discuss the empirical findings focussing on the core concepts of meaning of home and sense of belonging for new retirees to an area. Findings: For new retirees, there exists a zone between the home and community, that can be viewed as a geographic space comprised of overlapping and interwoven personal, social and physical domains. This zone between the physical house and the surrounding community can be construed as having certain elastic qualities and permeable boundaries that blur the distinctions between home and community. A focus on the micro-environment of the home dwelling and the macro-environment of the neighbourhood and community then appears relevant for understanding place attachment for these persons. This idea of the ‘home beyond the house’ – is one of the most important contributions of this research. Our results view the heuristic framework of Oswald and Wahl as a valuable tool for building understanding about the meaning of home for older adults by drawing attention to the domains themselves, and more importantly, to the interrelationships between them. Consequently, for younger in-migrants, the boundary between home and community blurs into one larger, symbolic entity experienced as ‘home’.  相似文献   

17.
In a world of sensory overload, it is becoming increasingly important to provide environments that enable us to recover our sense of well being. Such restorative (‘tranquil’) environments need to comprise sufficient sensory stimulation to keep us engaged, whilst at the same time providing opportunity for reflection and relaxation. One essential aspect in safeguarding existing, or developing new ‘tranquil space’, is understanding the optimum relationship between the soundscape and the visual composition of a location. This research represents a first step in understanding the effects of audio-visual interaction on the perception of tranquillity and identifies how the interpretation of acoustic information is an integral part of this process. By using uni and bi-modal auditory-visual stimuli in a two stage experimental strategy, it has been possible to measure the key components of the tranquillity construct. The findings of this work should be of particular interest to those charged with landscape management, such as National Park Authorities, Regional Councils, and other agencies concerned with providing and maintaining public amenity.  相似文献   

18.
New plant taxa from around the world continue to be imported into Australia and New Zealand. Many of these taxa have the potential to become agricultural or environmental weeds and this risk needs to be assessed before allowing their entry. A weed risk assessment system is described that uses information on a taxon's current weed status in other parts of the world, climate and environmental preferences, and biological attributes. The system is designed to be operated by quarantine personnel via a user-friendly computer interface.The model was tested against experts' scores for weediness for 370 taxa present in Australia, representing both weeds and useful taxa from agriculture, the environment, and other sectors. The model was judged on its ability to correctly ‘reject’ weeds, ‘accept’ non-weeds, and generate a low proportion of taxa which could not be decisively categorised, termed ‘evaluate’. More than 70% of the taxa were rejected or accepted. All taxa classified as serious weeds, and most minor weeds, were rejected or required further evaluation, while only 7% of non-weeds were rejected. The model was modified to New Zealand conditions and evaluated against the opinions of several groups of experts and against economic measures. The model produced a weediness score very similar to the mean of the experts scores. The latter were highly variable: agriculturalists tended to accept known weeds, conservationists tended to reject most adventive taxa, and only botanists produced scores similar to the model. The model scores also tended to be independent of economic value as measured in this study. The model could be adapted for use as a screening tool in any region of the world.  相似文献   

19.
20.
The environmental perception wave at Clark University was already in full swing when Anne Buttimer arrived in Fall 1970 with curiosities about social space, ‘insiders’ and ‘outsiders’, ‘home’ and ‘reach’, from a project on residential area design in Glasgow, Scotland. Lessons learned from the intense interaction between geographers and psychologists were enormously valuable for subsequent work with geography students at Clark during the 1970s. Since then she has worked on temporality and environmental experience, migration and identity, with colleagues in Sweden, and has pursued autobiographically-based approaches to questions of creativity and context and the history of geographic thought and practice. In retrospect, she claims, one of the most valuable results of the perception wave was to provoke awareness of the lenses through which reality is experienced by people in different cultures, and that includes the disciplinary cultures into which researchers themselves are socialized.  相似文献   

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