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121.
This article, both theoretical and methodological in nature, argues the potential merits of using a net benefits’ framework as a tool to aid policy makers in their efforts to compare Salton Sea restoration alternatives and inform the public as to the potential magnitude and distribution of trade-offs associated with each alternative. A net benefits’ approach can provide a more accurate comparison and evaluation of the potential net returns from public spending on Salton Sea restoration than what would be provided under the suggested criteria of current legislative mandates. Furthermore, a net benefits’ framework provides a more lucid and systematic accounting framework by which to enumerate the full array of benefits and costs of each alternative for policy analysis. Finally, net benefits’ analysis serves to add transparency to the decision-making process so that the public gains an understanding of how its scarce resources, including both financial and natural capital, are being appropriated. Additionally, we illustrate and emphasize the importance of estimating the non-market values associated with many of the ecosystem services provided by the Salton Sea and describe the major techniques that do so. Guest editor: S. H. Hurlbert The Salton Sea Centennial Symposium. Proceedings of a Symposium Celebrating a Century of Symbiosis Among Agriculture, Wildlife and People, 1905–2005, held in San Diego, California, USA, March 2005  相似文献   
122.
After providing background on Dendrolagus species in Australia, two consecutive surveys ofBrisbane's residents are used to assess public knowledge of tree-kangaroos and the stated degree of supportfor their conservation in Australia. The responses of participants in Survey I are based on their pre-surveyknowledge of wildlife. The same set of participants completed Survey II after being provided with additionalinformation on all thewildlife speciesmentioned in Survey I.Changes in the attitudes of respondents and theirdegree of support for the protection and conservation of Australia's tree-kangaroos are measured, includingchanges in their contingent valuations and stated willingness to provide financial support for such conservation.Reasons for wanting to protect tree-kangaroos are specified and analysed. Furthermore, changesthat occur in the relative importance of these reasons with increased knowledge are also examined. Supportfor the conservation of tree-kangaroos is found to rise with the additional knowledge supplied about allspecies and is compared with variations in support for protection of other mammals. Support for the conservationof Australia's less well known tropical mammals is found to increase relative to better knownmammals (icons) present in temperate areas, such as koalas and red kangaroos. Possible implications of theresults for government conservation policies in Australia are examined.  相似文献   
123.
The implementation of sustainable management plans for protected areas is one of the main challenges for public institutions. These plans involve public participation and the assessment of social benefits provided by these open spaces. This work proposes the use of choice experiments methodology for the evaluation of management alternatives for a protected area. The case study within this work is El Valle and Carrascoy Natural Park, which is included in the Natura 2000 Network. This Protected Natural Area (PNA) is located in a peri-urban area; thus, it combines high natural values and high anthropic pressure. A Choice Experiment (CE) was designed through consultation with the Park managers and technicians, and it was applied to a representative sample of the population within the Region of Murcia (South-Eastern Spain). CE allowed an estimation of the value of different management alternatives, classified according to the three main sustainability areas: social; economic; and, environmental. The results show population's demand for environmental management alternatives, such as protection of flora and fauna and promotion of ecotourism, as well as a rejection of quarrying in the PNA. The economic values estimated allow the proposal of a distribution of the annual budget of the PNA according to the social demand.  相似文献   
124.
It is generally recognised that the valuation in LCA requires political, ideological and/or ethical values (hence the term). These values, however, are seldom discussed, and this paper may he seen as an early attempt. One result is that not only the valuation weighting factors, but also the choice of valuation methodology and the choice of using a valuation weighting method at all, are influenced by fundamental ethical and ideological valuations. Since there is no societal consensus on these fundamental values, and never will be one in an open democratic society, there is no reason to expect consensus either on valuation weighting factors, or on the valuation method or even on the choice of using a valuation weighting method at all. Another result of the discussion on values is that the ethical and ideological valuations are often made implicitly in the choice of method, data, etc., thus making it difficult to discuss the values and the implications of different standpoints. Although this paper focus on the valuation methods within LCA, it is expected that much of the discussion and the conclusions are of relevance for other environmental management tools, e.g. Environmental Impact Assessment.  相似文献   
125.
This article addresses the need for a structured and compre-hensive methodology for assessing the environmental perfor-mance of manufacturing processes. The analytic hierarchy pro-cess (AHP) is used as the basic framework for analyzing environmental impacts and improvement options following a streamlined life-cycle assessment (LCA) approach that is fo-cused on the manufacturing operation. The multicriteria de-cision analysis approach of the AHP is consistent with the LCA concept because the environmental factors can be hierarchi-cally structured into impacts and improvement options. Its po-tential as a valuation tool for impact and improvement assess-ment addresses both qualitative and quantitative issues in environmental decision making.
Through application to a pulp and paper manufacturing case study, the viability of the AHP for evaluating environmen-tal impacts and prioritizing process improvement options rela-tive to these impacts is demonstrated. AHP was used to pro-vide a quantitative tool for the design of a set of weighting factors for impact and improvement analyses.  相似文献   
126.
土壤阳离子交换量(CEC)是土壤施肥、改良的主要依据和土壤质量的评价指标,研究土壤CEC的空间分布及模型预测可为土壤养分监测、管理及精准农业实施提供科学依据。本研究以中宁枸杞林地粉壤土为对象,在自相关、交互相关等分析基础上,采用协同克里格(CoKriging)、普通最小二乘法(OLS)、地理加权回归(GWR)和随机森林(RF)模型对土壤CEC进行回归分析,比较了制图效果及模型预测精度。结果表明:中宁枸杞林地粉壤土CEC平均值为13.12 cmol·kg^-1,属中等肥力;土壤CEC的空间分布具有自相关性,并与土壤pH、有机质、黏粒和电导率在不同滞后距离上存在不同的空间相互关系;RF模型预测图避免了CoKriging、OLS和GWR模型预测图中土壤CEC图斑边界两侧破碎程度大、突变明显的缺陷,使土壤CEC在空间变化上表现为自然、平缓的过渡;RF模型RMSE值分别比CoKriging、OLS和GWR模型减少33.82%、20.55%和19.81%,R^2分别提高8.84%、51.92%和7.69%。RF模型考虑了样点空间位置,明显提高了插值精度且制图效果更加平缓。  相似文献   
127.
Positron emission tomography (PET) with FDG has a prominent role in the staging of lymphoma, including Hodgkin's lymphoma and aggressive non Hodgkin's lymphoma. Its value in the assessment of end therapy response is also well established, especially with residual masses on CT scan to differentiate between fibrosis (scar) and active tissue. International experts with the International Harmonization Project of lymphoma have proposed a set of interpretation criteria. Finally, FDG-PET looks very promising in the early response assessment; it has shown to be predictive of chemosensitivity and of therapy response. Interpretation criteria have been improved and proposed. FDG-PET usefulness is being evaluated in national and international research protocols where therapeutic strategies are based on FDG-PET results.  相似文献   
128.
A ruminant's early experience with low-quality food (LQF) is expected to increase its acceptance and preference in adulthood. Contrarily, we found that experienced sheep (ES) exposed to mature oat hay early in life ate less of this LQF than inexperienced sheep (IS). A possibility is that ES might have devaluated the LQF through continuous comparisons against high-quality food (HQF) supplements (sunflower meal and ground corn) that were simultaneously available during early experience. In this study, we tested the devaluation hypothesis with a successive negative contrast (SNC) procedure. In a consummatory SNC procedure, 'shift' subjects are unexpectedly changed from HQF to LQF, and their consumption is then compared against the consumption of 'unshift' subjects that receive LQF all throughout the SNC procedure. The magnitude of the difference in consumption between preshift and postshift is regarded as a measure of the degree to which both foods (HQF and LQF) are perceived to differ hedonically. When sheep from our previous study were 300 days old, both ES and IS were randomly assigned to either shift (ES-S and IS-S) or unshift conditions (ES-U and IS-U; n = 6 in each group). Groups ES-S and IS-S were fed HQF (alfalfa hay) during the preshift phase, and then suddenly changed to LQF (oat hay) in the postshift phase. Groups ES-U and IS-U (controls) were fed only LQF throughout the SNC procedure. Subjects in ES-S showed a significantly lower intake of LQF than those in ES-U in the first postshift session (i.e. they showed an SNC effect), which was not observed in IS. These results agree with ES subjects having devalued LQF during early experience. We discuss the possibility that high levels of nutrient supplementation can result in devaluation of LQF (i.e. decrease in preference and acceptance), whereas restricted levels of supplementation may promote a positive experience with LQF.  相似文献   
129.
The Knuckles range of forests has been identified as a unique biological resource in Sri Lanka with much biodiversity. It is also important as a watershed which feeds the Mahaweli reservoir system. Having considered the present hazardous land-use practices such as cardamum production and shifting cultivation, the Knuckles range has been declared a national wilderness area. The Forest Department is in the process of preparing the management plan for the area. There are about 48 villages in the vicinity of the forest. This study attempts to estimate the composition of income in the peripheral communities, ticularly the extraction of non-timber forest products (NTFP) from this range of forests. Data were collected using structured questionnaires from 60 households in three villages in the vicinity of the forest. The rural economy is described using a farming systems approach and the net income contributed by each activity in the farming system was estimated. Results show that nine components of the farming system use resources from the village and the forest, with at least 47 plant species used by the villagers for different purposes. Cardamum production and shifting cultivation contribute significantly to the total income of the household, but the majority of households in the study depend upon forest resources to supply some portion of their income. Nevertheless, the monetary value of the annual income generated by NTFP is much lower than income from either cardamum production or shifting cultivation. If cardamum production and shifting cultivation are to be restricted under the conservation program, there could be additional pressure put on NTFP. Therefore, we suggest a study of the natural regen-eration capacity of selected NTFP; such information should be used in finalizing the management plan in the Knuckles range of forests.  相似文献   
130.
Evaluations about social preferences for ecosystem services do not always include human well-being. Using a case study in South-Central Chile, we showed how the human well-being approach might reveal social preferences on ecosystem services. We used a socio-cultural approach to compare social preferences for provisioning, regulating, and cultural services and the links people establish to human well-being. From an online questionnaire, we collected 214 responses, balanced in gender (49/51 % men/women, respectively), diverse in age (18 to 62 years), but with 68 % under 30 years. Water for human consumption and agriculture, food, and native forest products were the most preferred provisioning services (40, 28, and 21 %, respectively). In contrast, products from tree plantations were considered the lowest ones. Pollution control (40 %) and water provision during summer (18 %) were the preferred regulating services, while biodiversity conservation (25 %) and environmental education (22 %) were primarily selected cultural ones. We found a clear preference pattern for provisioning services but not for regulating and cultural services. Even though people linked multiple ES to human well-being, some links’ patterns mirrored preferences for provisioning services but not for regulating and cultural services. However, although cultural services did not show a clear preference pattern, people perceived their importance by linking them to various benefits. Understanding social preferences of ES based on their links with human well-being helps to address their relevance and potential trade-offs for land planning and management decision-making and convert the ES concept into decision-making instruments.  相似文献   
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