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271.

Many cities and national authorities have made substantial progress in developing transport strategies to reconcile environmental pressures with the increasing demand for travel. However, there is still some doubt as to what are the key ingredients of a successful strategy and progress in implementing such changes has been slow. Research is needed to better understand what are the essential ingredients to a balanced transport policy, the constraints, which are preventing these from being implemented, and the acceptability of such changes. This paper reports on the outcomes of a project funded under the Rees Jeffreys Road Fund research programme 'From Realism to Reality', which aims to identify the elements necessary for a successful transport policy in the UK into the 21st century, The project seeks to develop a vision for the transport system of the future through an understanding of the extent of the current problems in the transport sector and an examination of the range and effectiveness of options and instruments available to resolve them. The paper examines a range of visions that are currently in the public domain. Results show that there is a degree of consistency in the general aims and objectives of such visions, but that there is rather less consensus in the means proposed to achieve those aims.  相似文献   
272.
Compassionate conservation is based on the ethical position that actions taken to protect biodiversity should be guided by compassion for all sentient beings. Critics argue that there are 3 core reasons harming animals is acceptable in conservation programs: the primary purpose of conservation is biodiversity protection; conservation is already compassionate to animals; and conservation should prioritize compassion to humans. We used argument analysis to clarify the values and logics underlying the debate around compassionate conservation. We found that objections to compassionate conservation are expressions of human exceptionalism, the view that humans are of a categorically separate and higher moral status than all other species. In contrast, compassionate conservationists believe that conservation should expand its moral community by recognizing all sentient beings as persons. Personhood, in an ethical sense, implies the individual is owed respect and should not be treated merely as a means to other ends. On scientific and ethical grounds, there are good reasons to extend personhood to sentient animals, particularly in conservation. The moral exclusion or subordination of members of other species legitimates the ongoing manipulation and exploitation of the living worlds, the very reason conservation was needed in the first place. Embracing compassion can help dismantle human exceptionalism, recognize nonhuman personhood, and navigate a more expansive moral space.  相似文献   
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Integrated analysis of land-use change in support of informed policy-making for sustainable land use at various spatial levels makes heavy requirements for quality data. This paper aims to structure the principal methodological and practical issues of data needs for this task. The data needs for local level analyses of land-use change are given special attention. The paper adopts an integrated economic–environmental modeling framework and suggests the main types of data needed. Four main data dimensions are distinguished: system of spatial reference, system of temporal reference, definitions, and data collection procedures (sources, collection instruments and techniques, recording and retrieval systems, data format, frequency of data collection). To evaluate the suitability of current data sets as well as to guide the collection of new ones, a scheme based on substantive and practical criteria is employed. The former include compatibility, consistency, and reliability of data, while the latter include availability, ease and cost of data collection/retrieval, and transferability of data. The evaluation indicates the broad gaps in current data sets along the four main data dimensions. Based on this evaluation, the paper suggests framework guidelines to address the main data issues identified. RID=" ID=" <SUP>1</SUP>CLAUDE: Coordinating Land Use and Land Cover Data and Analyses in Europe. European Commission Concerted Action project (DG-XII); DAPLARCH: Data Plan Development for Land Use and Land Cover Change Research. Program sponsored by IGBP-IHDP (LUCC and DIS). Street, Durham, North Carolina 27707, USA  相似文献   
275.
The Context for Substitutes in CVM Studies: Some Empirical Observations   总被引:3,自引:0,他引:3  
The purpose of this paper is to report results from a set of experiments that provide data to test the NOAA [13] Panel recommendation that subjects be reminded of budgetary substitutes when providing values. The results suggest that simply reminding subjects of alternative environmental goods does not affect the distribution of values for a specific good. Such values are affected, however, whenever subjects simultaneously value alternative goods.  相似文献   
276.
Natural factors and human modifications contribute to the estimated annual loss of 10,200 ha of coastal land in the Mississippi River Deltaic Plain Region of south Louisiana. This paper combines information on regional geology and human-induced habitat alterations to evaluate the relative importance of human and natural factors to marsh loss. Data on marsh area and habitat type for 139 7.5-min quadrangles were calculated from maps based on aerial photographs from 1955/56 and 1978, and data on regional geology obtained from published maps were used to construct multivariate model relating initial marsh area, change in urban and agricultural area, change in canal and spoil area, canal area in 1978, depth of sediment overlying the Prairie terrace, and subdelta age to marsh loss. The model indicated that between 25.0% and 39.0% of the marsh loss that occurred during the 23-year period was related to canal and spoil construction, and between 9.5% and 12.7% was related to urban and agricultural development. These are minimal estimates of loss because they do not include many secondary effects (for example, canal orientation, saltwater intrusion, and eutrophication) that can also result in indirect loss. Depth of sediment, initial marsh area, delta lobe age by 1978 canal and spoil area interaction, and indirect effects not included in the model accounted for remaining marsh loss.  相似文献   
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Planning effective strategies to combat air pollution in amajor city such as London requires integration ofinformation on atmospheric concentrations and where theyexceed prescribed air quality standards, detailed data onemissions and potential measures to reduce them includingcosts, and a good understanding of the relativecontributions of different emission sources to pollutantconcentrations plus the remaining background. The UrbanScale Integrated Assessment Model (USIAM) is designed as atool to integrate such information, and to explore andassess a variety of potential strategies for improving airquality. It is based on the same principles as theAbatement Strategies Assessment Model (ASAM) that has beenused in the UN Economic Commission for Europe. To startwith the USIAM model is being developed with respect to theparticulate PM10 only, and in particular the primaryparticulate contribution. The secondary particulate istreated as part of the background superimposed on theprimary particulate concentrations; this may need to betreated more specifically at a later stage, particularlywith respect to nitrate formation over the city. The USIAMmodel therefore sets out to examine a selection of severeepisode conditions as well as long-term annual averageconcentrations, and aims to find strategies that aresuccessful in eliminating exceedance of the prescribedtarget concentrations. By ranking different options forabatement of emissions, for example in terms of cost orease of implementation, the USIAM model can also select andprioritise different potential strategies.  相似文献   
280.
/ This paper reports on the development of abiogeographic-based protected area selection procedure (PASP) that addresseslimitations of current reserve selection methods such as inflexibility,restrictive criteria structures, and disregard of social criteria. We arguethat selection criteria are legitimately identified through the politicalprocess and can therefore have both social and biological content. PASPprovides a systematic, flexible and efficient procedure for identifying anetwork of protected areas that satisfies a given set of selection criteria.PASP has 11 steps divided into three main stages: compilation, selection, andvalidation. A selection algorithm is used into which criteria specific to thebiogeographic region under study can be incorporated. The procedure is ableto accommodate both nominal and ranking criteria and gives the analyst theopportunity to specify thresholds and targets for each criterion. Otherfeatures of PASP include the minimization of data collection effort,consideration of reserve design principles, and inclusion of a networkevaluation as a check to ensure that politically determined objectives havebeen met.KEY WORDS: Land use; Protected area networks; Selection algorithms  相似文献   
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