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21.
Using an economic approach to provide a rationale for rainforestconservation has been a popular exercise in recent years. This paper uses suchan approach to assess the net value of the Arabuko Sokoke Forest in Kenya. Theeconomic benefits associated with the forest derived by local and globalpopulations are estimated by combining evidence from existing studies and theresults of a contingent valuation study carried out by the authors. Thesebenefits are set against the cost of preserving the forest to the Kenyan ForestDepartment. Even when the opportunity cost of the forest land is omitted fromthe costs of forest preservation, and when the revenues generated from theGlobal Environment Facility (GEF) funded project are included, the costs offorest conservation outweigh the benefits. It is only when non-use andexistencevalues are included (which are not realised by the Kenyan population) that theforest benefits exceed the costs. The paper concludes by arguing that, althoughsome projects within the Arabuko Sokoke Forest have been successful incapturingsome of the economic value associated with the forest, more needs to be done todesign additional capture mechanisms so that a greater proportion of the globalbenefit of the forest can be realised by local populations and localgovernments.  相似文献   
22.
In this article, we discuss molecular mechanisms involved in the evolution of amygdala kindling and the episodic loss of response to pharmacological treatments during tolerance development. These phenomena allow us to consider how similar principles (in different neurochemical systems) could account for illness progression, cyclicity, and drug tolerance in affective disorders. We describe the phenomenon of amygdala-kindled seizures episodically breaking through effective daily pharmacotherapy with carbamazepine and valproate, suggesting that these observations could reflect the balance of pathological vs compensatory illness-induced changes in gene expression. Under certain circumstances, amygdala-kindled animals that were initially drug responsive can develop highly individualized patterns of seizure breakthroughs progressing toward a complete loss of drug efficacy. This initial drug efficacy may reflect the combination of drug-related exogenous neurochemical mechanisms and illness-induced endogenous compensatory mechanisms. However, we postulate that when seizures are inhibited, the endogenous illness-induced adaptations dissipate (the “time-off seizure” effect), leading to the re-emergence of seizures, a re-induction of a new, but diminished, set of endogenous compensatory mechanisms, and a temporary period of renewed drug efficacy. As this pattern repeats, an intermittent or cyclic response to the anticonvulsant treatment emerges, leading toward complete drug tolerance. We also postulate that the cyclic pattern accelerates over time because of both the failure of robust illness-induced endogenous adaptations to emerge and the progression in pathophysiological mechanisms (mediated by long-lasting changes in gene expression and their downstream consequences) as a result of repeated occurrences of seizures. In this seizure model, this pattern can be inhibited and drug responsivity can be temporarily reinstated by several manipulations, including lowering illness drive (decreasing the stimulation current.), increasing drug dosage, switching to a new drug that does not show crosstolerance to the original medication, or temporarily discontinuing treatment, allowing the illness to re-emerge in an unmedicated animal. Each of these variables is discussed in relation to the potential relevance to the emergence, progression, and suppression of individual patterns of episodic cyclicity in the recurrent affective disorders. A variety of clinical studies are outlined that specifically test the hypotheses derived from this formulation. Data from animal studies suggest that illness cyclicity can develop from the relative ratio between primary pathological processes and secondary endogenous adaptations (assisted by exogenous medications). If this proposition is verified, it further suggests that illness cyclicity is inherent to the neurobiological processes of episode emergence and amelioration, and one does not need to postulate a separate defect in the biological clock. The formulation predicts that early and aggressive long-term interventions may be optimal in order to prevent illness emergence and progression and its associated accumulating neurobiological, vulnerability factors.  相似文献   
23.
The financial returns to Kenyan tourism demonstrate the importance of the country's tourist potential to its economic development. Protected areas and their inhabitants are the principal focus of the tourist industry, the nations's main foreign exchange earner, and a source of wonder and value for a global population of non-users. It might be expected that such assets would be accorded some degree of security with sufficient funding to safeguard current and potential economic benefits. Yet park use is haphazard, and there is frequently little coincidence between those that benefit and those that pay for the continued existence of such areas. Growing economic and demographic pressures which threaten to swamp protected areas only emphasize the implicit subsidy currently paid by Kenyans to support conservation for the benefit of the world at large. In this climate the case for conservation depends on the measurement and capture of economic benefits. Using a contingent valuation survey of expressed preference this study estimates the consumer surplus attached to current non-consumptive use of protected areas by foreign visitors at some $450 million per annum. This sum alone is more than double the best available estimate of opportunity cost and appears to justify current resource use. The estimate is additional to current financial returns from tourism and makes no allowance for other direct and indirect benefits and potential returns from consumptive uses. Measured consumer surplus contains some margin of willingness to pay that could be captured through the current fee structure. Moreover, park fees represent the most accessible market mechanism to finance revenue sharing and additional park investment before potential recourse to emerging global market institutions.  相似文献   
24.
25.
The field of regenerative medicine (RM) faces many challenges, including funding. Framing the analysis in terms of institutional politics, valuation studies and “technologies of knowledge”, the paper highlights growing debates about payment for RM in the UK, setting this alongside escalating policy debates about “value”. We draw on interviews and publicly available material to identify the interacting and conflicting positions of institutional stakeholders. It is concluded that while there is some common ground between institutional stakeholders such as industry and health system gatekeepers, there is significant conflict about reward systems, technology assessment methodologies and payment scenarios; a range of mostly conditional payment schemes and non-mainstream routes are being experimented with. We argue that current developments highlight a fundamental conflict between a concern for the societal value of medical technologies in a resource-limited system and a concern for engineering new reward and payment models to accommodate RM innovations.  相似文献   
26.
Summary Hartfield Park bushland represents a typical area of Perth urban bushland, and is identified as one site worthy of protection in the Western Australian Government's Bush Forever Plan. Two thirds of the Reserve is developed and parts of the remaining bushland are under threat of future development for parking and playing fields. This paper reports a study undertaken to estimate the economic value placed by the community on a specified urban bushland site using the contingent valuation method, a stated preference, non‐market valuation technique which captures both use and non‐use values. Because environmental goods such as urban bushland exist without organized markets, they are often omitted from the decision‐making process regarding the socially optimal management of resources. In estimating a valuation for Hartfield Park, it may be included in any cost–benefit analysis conducted for the site in future. A survey was conducted across the Perth metropolitan area during April 2001 that involved the mail out of 1000 questionnaires to names and addresses obtained at random from the Western Australia Electoral Roll. A 54% response rate was obtained. Regression analysis was used to predict the probability of people being willing to pay for the preservation of this urban bushland and the significant predictors of willingness to pay related to income and educational levels rather than proximity to or knowledge of the site. Willingness to pay was also estimated and the results indicate a conservative mean willingness to pay for the preservation of the bushland of $A21.60 per person per annum. Extrapolation of this figure across the total adult metropolitan community resulted in an estimated valuation of $A16.6 million. Median willingness to pay was also estimated and equalled $A4.35 per person per annum with a valuation for the total adult metropolitan community equal to $A3.3 million. Extrapolation of these mean and median figures across Perth households rather than adult individuals resulted in an estimated valuation of $A9.6 million and $A1.9 million, respectively. These figures indicate that the community value for this environmental amenity may exceed the costs of providing alternative facilities elsewhere.  相似文献   
27.
More conservation-oriented forest management practices have been implemented recently in the Nordic countries. The goal of this ecological forest landscape management is to reconcile the commercial harvesting of boreal forests with biodiversity conservation. Management aims at maintaining viable populations of the full array of naturally occurring species in an area while still keeping the timber flow as maximal as possible. Basic ecological tools of managing landscape for biodiversity are (1) to mimic natural disturbance regimes, (2) to set aside areas in permanent or temporary nature reserves, and (3) to enhance dispersal of organisms by creating habitat corridors and stepping stones. The ecological basis of this management system is not well founded, and much more empirical and theoretical research is needed to justify and further develop forest landscape management. It has also proved difficult to assess the economic consequences of more conservation-oriented forest management because the market economy largely fails to give value to forest products other than fibre. Considerable methodological development in the valuation of non-timber goods has occurred in recent years, but there is still much controversy over the justification of the valuation procedure in principle. It seems that both economic and moral approaches to the issue of valuation are inseparable from the choices and decisions we have to make about ecological systems. Perhaps the most fruitful outcome can be achieved by using moral and economic arguments in parallel.  相似文献   
28.
陈述性偏好法是当前用于评估环境物品非市场价值的主要方法,包括条件价值评估法(CVM)和选择实验(CE).本文利用陈述性偏好法对三江平原湿地的生态保护价值进行评估,基于随机效用理论构建陈述性偏好方法的支付意愿评价模型,求出基于CVM与CE的三江平原湿地生态保护价值的支付意愿(WTP).结果表明: 基于CE的平均支付意愿为每年379元,不同选择属性的边际支付意愿分别是水源涵养为每年114.00元,湿地面积为每年72.55元,自然景观为每年59.55元,生物多样性为每年37.09元;CVM的平均支付意愿为每年134元.分析支付意愿的影响因素,并对受访者拒绝支付原因进行探讨.CE方法得到受访者的支付意愿显著高于CVM方法,社会经济属性中受教育程度和个人平均年收入与受访者的支付意愿呈显著正相关,而拒绝支付原因没有显著差异.CE可以进行多属性、多水平分析,求出湿地各选择属性的支付意愿,因此CE比CVM更能揭示受访者的偏好信息,其评估结果更接近于实际.  相似文献   
29.
The Natural Capital Initiative (www.naturalcapitalinitiative.org.uk) held its first conference ‘Valuing our life support systems’ at Savoy Place, London, from 29 April to 1 May 2009. The aim of the conference was to discuss different perspectives on, and solutions to, the conservation and sustainable use of ecosystem services. It particularly focused on the link between the environment and the economy, and how to implement an ecosystem approach to environmental management. This event brought together scientists across the natural and social sciences, alongside representatives from government, non-governmental organizations, business and industry.  相似文献   
30.
In Japan, requirements for the development of valuation methodology are very stringent. Several methodologies have been proposed to meet these demands in recent years. These methods, however, are quite different in many points such as selected impact categories, the numbers of substances considered, and basic concepts for the environment. The results of LCA are fully dependent on the goals of LCA practitioners and commissioners. If they misunderstand the concept of method and use it, the result may not fit for the purpose. Consequently, it is important to characterize the methods selected by the practitioner in accordance with their LCA goals. In this paper, weighting methodologies proposed in Japan have been introduced with a comparison between the results of case studies for common industrial products. Furthermore, we considered the present situations and future directions of valuation methodologies in Japan. This consideration is carried out based on the results of investigations performed by the Impact Assessment Committee of the National LCA Project of Japan  相似文献   
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