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In this study we evaluate the accuracy of four global and regional forest cover assessments (MODIS, IGBP, GLC2000, PROARCA) as tools for baseline estimation. We conduct this research at the national scale for Costa Rica and for two tropical dry forest study sites in Costa Rica (Santa Rosa) and Mexico (Chamela-Cuixmala). We found that at the national level, the total forest cover accuracy of the four land cover maps was inflated due to an overestimation of forest in areas with an evergreen canopy. However, the four maps greatly underestimated the extent of the deciduous forest (dry forest); an ecosystem that faces high deforestation pressure and poses complications to the mapping of its extent from remotely sensed data. For the tropical dry forest sites, all maps have low forest cover accuracies (mean for Santa Rosa: 27%; mean for Chamela-Cuixmala: 56%). This has implications for policy implementation.  相似文献   

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This paper describes an approach to account for asymmetric preference formation in discrete choice models used for environmental valuation. The paper draws on data from a case study on preferences for environmental change resulting from a hypothetical rural development and conservation programme in Indonesia. Local knowledge on the current state of the environment was used to define an individual-specific status quo that consistently frames changes in a range of environmental services as gains or losses matching the perceptions of the local population living in the vicinity of a National Park. I estimated choice models that included separate parameters for increases and decreases in attribute levels for the environmental services and derived the indicators of local willingness to pay (WTP) corresponding to the bidirectional changes relative to the individual-specific status quo option. I found clear evidence of an asymmetric response to increase and decrease in attribute levels relative to the status quo. Ignoring asymmetric preference formation can therefore result in biased estimates of WTP indicators and welfare measures of change in cases where the outcomes of environmental programmes can plausibly result in both an increase and a decrease relative to a reference option. Compared to a symmetrical modelling approach, the combination of simultaneously accounting for asymmetric preference formation and preference heterogeneity in the choice model yielded additional insights that may be used to inform the development of local strategies towards biodiversity conservation.  相似文献   

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This paper describes three relatively recent innovations in the Dutch agri-environment programme which have helped nature management to be contiguous with natural features allowing the landscape to be managed whole rather than piecemeal—and thus generate higher quality and greater scope in environmental management. The first two, joint submissions by neighbouring farmers and payments related to the level of environmental output delivered, are scheme innovations. The third, Environmental Co-operatives (EC)—clubs of neighbouring farmers that inter alia co-ordinate and help manage the scheme innovations—is an institutional innovation. None has an equivalent in the UK. Evidence from interviews with farmer and non-farmer members, policy makers, academics and other interested parties show the role EC play in overcoming some of the postulated problems of the two scheme innovations. Not all the problems have been overcome, and cost-benefit analyses have not been conducted, nevertheless there is sufficient evidence to suggest that these innovations have benefited all actors involved: farmers, the government, the environment and the rural economy. Analysis of UK agri-environment policy using actor network theory (ANT) suggests the UK government will need to show similar levels of trust in and commitment to the farming community before these innovations could be introduced in the UK.  相似文献   

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读书是学习,读树也是学习,是一种在户外感受自然、师法自然的学习,若能读出树的沧桑,听懂树的倾诉,那你的爱便是到了超凡脱俗的境界。   在北京麋鹿苑的户外生态教育活动中,有一个由二人进行的“读树”游戏,十分引人入胜。蒙面者在同伴的带领下,来到某棵大树前,通过用手触摸、用耳聆听、用心阅读,引发你对树木的亲和力,提高你对自然的感受力。做完游戏,你一定颇有感慨,那就请你一吐为快,与大家共享吧。   最近,美国自然教育家柯内尔来京教授了许多游戏,其中有一个叫“我的树”,是以人扮树,通过角色的转换,体验树的…  相似文献   

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Production methods for food from U.K. livestock industries (milk, dairy products, meat, eggs, fibre) are undergoing substantial change as a result of the need to respond to environmental and animal welfare awareness of purchasing customers, and to espouse the principles of environmental protection. There appears to be a strong will on the part of livestock farmers to satisfy the environmental imperative, led by the need to maintain market share and by existing and impending legislation. There has been support forthcoming in the form of Government-sponsored scientific research and technological development to provide the necessary framework for new environmentally sensitive practices. The agricultural community has itself made substantial responses to market demand through the inception of Farm Assured Quality Assurance Schemes. These appear to have a more sustainable future than the extremes of organic farming and free-range practices. Pollution of agricultural land with nitrate and phosphate by intensive livestock industries is a greater problem in some parts of continental Europe than it is in the U.K. The distribution of livestock out of intensive units and into mixed farming systems, would require substantial restructuring of the industry. Many of the animal welfare requirements which have been forwarded as a part of the environmental agenda for agriculture have been voluntarily accepted by livestock producers. However, some major aspects, such as alternative housing systems for pigs and poultry, remain unresolved. Analysis of the science and technology support for the environmental imperative, especially from Government sources, would suggest that, although dramatically increased in recent years, environmentally orientated research remains a relatively small proportion of the whole. Whilst a movement away from governmental funding of volume production appears to be justifiable, there has not been an equivalent balancing of effort toward funding for product quality, sustainability, environmental protection and animal welfare. Nevertheless, the university education system is producing a generation of more environmentally aware agricultural science graduates who are opting to pursue Government-sponsored environmentally orientated postgraduate research programs.  相似文献   

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A synthesis of current empirical work in environmental aesthetics is overdue. Based on the twin criteria of methodological rigour and social relevance, four major approaches to environmental aesthetics are defined and described. A contemplative humanist approach is matched by goal-oriented activism. The planner, doomed to relevance, confronts the rigorously scientific experimentalist. Advances in environmental aesthetic research and practice will depend upon the fruitful collaboration of the four approaches.  相似文献   

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The purpose of indices is to summarize a large volume of information into a single number that is easy to understand and interpret. Environmental indices provide a composite picture of an environmental condition derived from a series of observed measurements and parameters. They are used as communication tools by regulatory agencies to characterize the state of a specific environmental system (air, water, and sediments) and to study the impact of regulatory policies on various environmental management practices. In the development of environmental indices, a few issues and problems have been encountered arising as a result of the abstraction of information and data. These problems are referred to as characteristic properties that include ambiguity, eclipsing, compensation and rigidity. These characteristic properties have long been identified and interpreted in Boolean (e.g., Yes/No) or qualitative (e.g., low, medium, high) terms. In this paper, we propose a new approach to describe the above stated characteristic properties on a continuous scale to evaluate and compare the behavior of various aggregation models. Our approach is based on developing penalty functions for each characteristic property. A water quality index example by Swamee and Tyagi (2000) is used to explain our approach. A detailed case study for a developing microbial risk index is also provided to show how the proposed approach can be extended to complex hierarchical systems. Results show that it is possible to improve aggregation models for index development. Future research directions to improve index development are also discussed.  相似文献   

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This article reviews the present status of environmental impact analysis (EIA) with special reference to India. In India, legislation already exists that makes EIA mandatory for every new project proposal. Critically analyzing the shortcomings of the present EIA practices, this article proposes a new framework to conduct an EIA, emphasizing that it should be part of the environmental management of the area or region. Among other things, we suggest the following important points: (1) that a comprehensive database of the region be developed for use for conducting an EIA; (2) that emission standards for the proposed industry be set and the existing standards for old industries be reviewed; (3) that a directory of experts be developed; and (4) that the Department of Environment should take responsibility for conducting EIA studies by forming a study team and an evaluation team for every EIA study with members drawn from the directory of experts.  相似文献   

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With increasing expenditures on improving environmental management, there comes a need to determine a return on this investment by measuring performance. One such means of measurement, GEMI's environmental self-assessment procedure (ESAP), is based on a goal of meeting leadership standards and is the focus of this case study. Designed to be a self-assessment tool, the ESAP reflects a company's perceived rating of environmental performance. This perception can be different from actual performance, depending on the objectivity exercised and the level of compliance assurance information available.  相似文献   

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This essay considers the value of phenomenology for environmental psychology, first, by examining differences between a conventional scientific approach and phenomenology; second, by presenting substantive phenomenological research meaningful for environmental psychology. Three substantive themes are discussed: (1) a phenomenology of human experience; (2) a phenomenology of physical environment; (3) a phenomenology of the person—world relationship. The essay concludes that conventional research in environmental psychology has sometimes uncritically accepted theories and concepts which are out of touch with the actual fabric of environmental behavior and experience. A phenomenological perspective looks at the person—environment relationship afresh and thus helps to revitalize the ontological, epistemological and methodological foundations of environmental psychology.  相似文献   

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