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701.
Mark Cox Edward B Barbier Piran C. L. White Geraldine A. Newton-Cross Lorraine Kinsella Heather J. Kennedy 《Preventive veterinary medicine》1999,41(4):221-270
The current 6-month quarantine system for all cats and dogs entering the UK has kept the UK rabies-free since 1922. However, pressure is mounting for a change to a system of vaccination, microchip identification and serological testing. In response to the increasing controversy surrounding the quarantine system, the UK government recently set up an independent review panel to assess the alternatives. This paper quantifies public preferences for the current policy and three alternative rabies-prevention measures. A survey was used not only to assess the overall preferences for rabies-prevention policies but also to assess the importance of policy attributes and socio-economic characteristics in determining policy preferences. We interviewed a sample of pet-owners in North Yorkshire. The results showed that the existing system was the single most-preferred policy option. However, a large proportion of the sample preferred the vaccination-based policies. A logistic-regression model and ordered probit models were used to find that safety and animal welfare were the most-important factors determining policy preferences. The respondents' awareness of the rabies-policy review, a desire to take a pet abroad, the amount of foreign travel, occupation and previous experience of quarantine were all important factors in policy choice. Socio-economic characteristics such as income, pets owned and the number of children were not significant determinants of policy preference. 相似文献
702.
Integrated watershed management (IWM) is vital in achieving agricultural sustainability in terms of both production and environmental protection. A decision support system (DSS) is useful in generating alternative decision scenarios for management of natural resources, facilitating the implementation of IWM concepts in an interactive and holistic way. The decision to implement an appropriate land use coupled with suitable soil and water conservation techniques not only enhances watershed health but also prevents sediment losses. Besides reducing basin fertility, such losses decrease the storage capacity of downstream reservoirs through silt deposition, which can, in turn, give rise to low biomass production and poorer flood control. In order to facilitate IWM, an effort was made to develop, in the Visual Basic programming language, a soil and water conservation DSS which considered both structural and cropping practices for arresting sediment loss. Input parameters to the DSS for a given tract of land included: mean slope; sediment loss; soil type; and land capability class (LCC). Outputs included decision criteria to choose among alternative structural measures and suggested cropping systems to serve as biological measures to reduce soil loss and conserve water. Structural watershed management measures included a variety of soil and water conservation structures widely adopted by farming communities throughout the world. The DSS is capable of providing sediment control solutions not only for small watersheds but also for larger drainage basins, by dividing the basin into smaller watersheds. The DSS was validated for a watershed on the Caribbean island of St Lucia and used to suggest measures for a 10° slope under specific soil type, sediment loss and LCC conditions. The measures proposed included bench terraces, graded contour bunds, conservation ditches, concrete chute spillways, diversion dams and conservation cropping systems. The measures actually adopted on‐site were conservation ditches, graded contour bunds and conservation cropping systems, a close parallel to the DSS's proposed measures. On slopes ranging from 5–55°, implementation of the suggested control measures resulted in a 34–37 per cent reduction in soil loss on the watershed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献