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Book reviews     
Saving the Coast: California's Experiment in Intergovernmental Land Use Control

Melvin B. Mogoluf

D. D. Heath and Co., Lexington, Mass. 1975, xiii + 136 pp., ISBN 0–669–97394–7

The Planning and Design of Rural Roads: The Implications of Landscape & Recreation

David N. Skinner

Scottish Tourist Board/Countryside Commission for Scotland. Price: £4.00

Comparative Land Use Planning and Regulation

Urban Planning Development Series No. 12, University of Washington, Seattle, 1975, 120pp.

’Modern Political Geography‘

R. Muir

Macmillan, 1975, 262pp., Paper cover £2.95; Hard cover £6.95.

Discussion Paper No. 10: “The Layfield Report and Local Government Finance"

G. C. Cameron (ed)

Discussion Papers in Planning, University of Glasgow

Assessment of Major Industrial Applications

Department of the Environment (1976) Research Report 13, H.M.S.O., £2

The Economic Impact of Tourism: a case study in Greater Tayside

D. M. Henderson (1975)

University of Edinburgh: Tourism and Recreation Research Unit

’Urban modelling: algorithms, calibrations, and predictions‘

M. Batty

Cambridge University Press, London, 1976, 381 pages, £17.50

’Urban fields‘

S. Angel and G. M. Hyman

Academic Press, London, 178pp., 1976, £5

Rural Planning Problems

Gordon E. Cherry (Ed.)

Leonard Hill, London, 1976, £6.95

’Living in Cities‘

Charles Mercer

Harmondsworth: Penguin Books, 240pp.

Shopping Centres—Planning, Development and Administration

Edgar Lion

Wiley: 1977, 198pp., £9.00.

The Home of Man

Barbara Ward

Penguin Books (Paperback) and Andre Deutsch (Hardback), June 1976, 294 pp., Indexed, 18 photographs, Paperback £1, Hardback £3.75

Runcorn New Town. Master Plan Amendment No. 2

Runcorn Development Corporation, 1975

Available from The Development Corporation, Runcorn New Town, Runcorn, Cheshire, WA7 5AR, 26 pp., Maps and Plans, Illustrated  相似文献   

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This study estimates the social benefits of wetland conservation in the Credit River watershed, located in an urban/peri urban area in Southern Ontario, Canada. A stated preference approach was employed to value wetland conservation programs which ranged from retaining the existing wetlands to restoring various levels of acres of wetlands over the 2009–2020 period. A total of 1,407 households completed an internet-based survey which presented trade-offs in binary choice scenarios framed as referenda. Responses were analyzed using various models, one of which was a latent class analysis which segmented respondents into three classes. This econometric approach uncovered significant preference heterogeneity for wetland conservation. Assignment of respondents to the classes suggested that about one-third of the sample was willing to pay small amounts to retain the existing wetlands. An additional third was willing to pay several hundred dollars a year for retention and small positive amounts for additional restoration. The final third were apparently willing to pay considerable sums for retention, but lesser amounts for additional restoration. However, further analysis revealed that respondents in this third class largely constituted yea-sayers. These results suggest caution in interpreting associated economic valuation estimates and highlight the importance of attempting to understand hypothetical bias in wetland and other such valuation studies.  相似文献   
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Abstract

Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness, similarity index, diversity index and evenness index etc. The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites.

The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon's phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations.

Due to the lack of enough knowledge and professional guide of conservation biological perspective, Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s. According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.  相似文献   
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Public lands occupied by feral horses in North America are frequently managed for multiple uses with land use conflict occurring among feral horses, livestock, wildlife, and native grassland conservation. The factors affecting habitat use by horses is critical to understand where conflict may be greatest. We related horse presence and abundance to landscape attributes in a GIS to examine habitat preferences using 98 field plots sampled within a portion of the Rocky Mountain Forest Reserve of SW Alberta, Canada. Horse abundance was greatest in grassland and cut block habitats, and lowest in conifer and mixedwood forest. Resource selection probability functions and count models of faecal abundance indicated that horses preferred areas closer to water, with reduced topographic ruggedness, situated farther from forests, and located farther away from primary roads and trails frequented by recreationalists, but closer to small linear features (i.e. cut lines) that may be used as beneficial travel corridors. Horse presence and abundance were closely related to cattle presence during summer, suggesting that both herbivores utilise the same habitats. Estimates of forage biomass removal (44 %) by mid-July were near maximum acceptable levels. In contrast to horse-cattle associations, horses were negatively associated with wild ungulate abundance, although the mechanism behind this remains unclear and warrants further investigation. Our results indicate that feral horses in SW Alberta exhibit complex habitat selection patterns during spring and summer, including overlap in use with livestock. This finding highlights the need to assess and manage herbivore populations consistent with rangeland carrying capacity and the maintenance of range health.  相似文献   
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Many accidents involve two-phase releases of hazardous chemicals into the atmosphere. This paper describes the results of the fourth phase of a Joint Industry Project (JIP) on liquid jets and two-phase droplet dispersion. The objective of Phase IV of the JIP was to generate experimental rainout data for non-flashing experiments, and to develop recommendations for the best methodology to predict rainout [total rainout mass and its spatial distribution (‘distributed’ rainout)].Phase IV of the JIP first included rainout experiments by the UK Health and Safety Laboratory (HSL) for sub-cooled releases of water and xylene with a range of orifice sizes and stagnation pressures. See the companion paper II for further details. Secondly model validation was carried out by DNV Software for these experiments using different correlations for the initial droplet size (Sauter Mean Diameter, SMD), i.e. the CCPS SMD correlation and the Phase III JIP SMD correlation. The validation includes flow rates, droplet size, distributed rainout and cloud temperature drop. Subsequently validation was considered for a wider range of experiments from the literature (sub-cooled and superheated releases) for both SMD and total rainout. Adopted rainout methods comprised both methods including explicit modelling of the droplets (using an extended version of Phast dispersion model UDM), as well as more simple methods based on rainout correlations without droplet modelling. Recommendations are made for the most accurate droplet size and rainout modelling. A modified CCPS UDM droplet size correlation has been shown to agree best against experimental rainout data.  相似文献   
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