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141.
This paper presents a simulation-based modelling approach for estimating total visitor numbers and amenity values for prospective non-priced open-access outdoor recreation sites. To begin, the geographic extent of the market for recreation at a policy site is estimated using data from a similar study site. The population residing within this geographic area is simulated using a spatial microsimulation model and GIS techniques and an individual-level ‘visitor arrival function’ is then transferred across this simulated population. This allows the latent demand for visits to the policy site by each simulated individual to be predicted and summed, providing an estimate of the total potential demand for recreation at the site. Combining this with an economic value measure of a visit provides an estimate of the potential amenity value of the policy site. The approach is applied to Moyode Wood, a small-scale forest in the West of Ireland, and estimates the potential total economic value of recreation at €0.4 million for the site. The research represents the first time that spatial microsimulation has been used in environmental benefit transfer and shows how it can be used to control for differences in demographic and spatial factors between study and policy sites. It also demonstrates how individual-level single-site travel cost models estimated using on-site survey data can be used to predict demand at alternative policy sites.  相似文献   
142.
Land-use change has a significant impact on the world’s ecosystems. Changes in the extent and composition of forests, grasslands, wetlands and other ecosystems have large impacts on the provision of ecosystem services, biodiversity conservation and returns to landowners. While the change in private returns to landowners due to land-use change can often be measured, changes in the supply and value of ecosystem services and the provision of biodiversity conservation have been harder to quantify. In this paper we use a spatially explicit integrated modeling tool (InVEST) to quantify the changes in ecosystem services, habitat for biodiversity, and returns to landowners from land-use change in Minnesota from 1992 to 2001. We evaluate the impact of actual land-use change and a suite of alternative land-use change scenarios. We find a lack of concordance in the ranking of baseline and alternative land-use scenarios in terms of generation of private returns to landowners and net social benefits (private returns plus ecosystem service value). Returns to landowners are highest in a scenario with large-scale agricultural expansion. This scenario, however, generated the lowest net social benefits across all scenarios considered because of large losses in stored carbon and negative impacts on water quality. Further, this scenario resulted in the largest decline in habitat quality for general terrestrial biodiversity and forest songbirds. Our results illustrate the importance of taking ecosystem services into account in land-use and land-management decision-making and linking such decisions to incentives that accurately reflect social returns.  相似文献   
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144.
The multiple effects of carbon values on optimal rotation   总被引:2,自引:0,他引:2  
Non-consumptive benefits which increase with crop age, like keeping carbon sequestered, lengthen optimal rotation compared with rotation for timber alone. High proposed carbon prices may extend rotation indefinitely. Carbon storage in wood products reduces this tendency. Biomass as an energy source displacing fossil fuels favours rotations near those of maximum biomass productivity. Use of sawn timber to displace structural materials with high embodied carbon favours somewhat longer rotations. Effects of rotation on soil carbon, and fossil carbon volatilised in harvesting operations, are further complications. Including all carbon effects results in optimal rotations somewhat longer than those based only on timber value, but shorter than those based on timber plus forest carbon. To include all factors intuitively is not possible: balanced appraisal needs economic calculations.  相似文献   
145.
In recent years it has been argued, from many perspectives, that the further into the future a value flow occurs, the lower is the appropriate discount rate for it. National governments are now beginning to authorise such declining discount rates. This viewpoint can be, and has been, formalised in various ways, and has been applied to evaluating forestry investments of given durations. When the optimal duration of investment is itself the issue, new problems arise. Lower discount rates make subsequent rotations longer than earlier ones, and for a given length more valuable than they would otherwise be. This affects the optimal length of earlier rotations, which in turn may affect the discount rate profile applicable to later ones. In the absence of analytical solutions for the optimal sequence of rotations, numerical protocols are needed. The results arising are mostly in accord with expectations. If the change of discount rate is due to expected changes of circumstance that are actually realised, then the optimal sequence of rotations will remain as initially determined. If, however, it is due merely to the particular time perspective of the present generation, rotations will be revised by future generations. This will lead to a sequence of rotations similar to that deemed optimal at the current short-term discount rate. The most important reductions in profitability caused by choosing the “wrong” discounting protocol arise from the “wrong” rate, rather than by using declining rates as such.  相似文献   
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147.
Transient processes important to understanding technical change are modeled using a time-varying version of the Sequential Interindustry Model, SIM. A simple process of technical change is explored, where a new production technique replaces an old one for one of an industry's production processes. Using several measures internal and external to the industry the model can help in understanding the complex processes of technical change, point to difficulties in their analysis, and suggest guidance to further examinations. An earlier version of this paper was presented at the Eighth International Conference on Input-Output Techniques, Sapporo, Japan, July 1986.  相似文献   
148.
149.
This paper examines some basic issues associated with supply chains in the context of acquiring local ingredients as part of producing a culinary tourism experience. Based on data collected from Executive Chefs at Relais & Châteaux restaurants through surveys and personal interviews, the authors document producer-to-chef relationships, why and how local ingredients are featured in menu listings, and how chefs communicate their use of local ingredients to their guests. The results also describe chefs’ beliefs about the use of local ingredients, as well as potential issues related to the use of suppliers and their perceptions of their guests’ expectations for their meals.  相似文献   
150.
In the light of the increasing pace and scale of tourism activity in New Zealand, the concept of sustainable tourism has become a key ingredient in the nation's tourism strategy. This paper explores sustainable tourism planning in New Zealand at the level of local government, and in particular, focuses on the implementation of the Resource Management Act 1991 (RMA) as a mechanism for achieving sustainable tourism. Using the findings of a survey of Regional Councils and Territorial Local Authorities, the paper explores public sector planning responses to tourism impacts and sustainability concerns in New Zealand. The paper extends the earlier work of Page and Thorn (1997. Towards sustainable tourism planning in New Zealand: public sector planning responses. Journal of Sustainable Tourism 5(1): 59-77; 2002. Towards sustainable tourism development and planning in New Zealand: the public sector response revisited. Journal of Sustainable Tourism 10(3): 222-238), which identified major issues of concern at local council level with regard to tourism impacts and argued the need for a national vision for tourism to ensure that the RMA achieved its original goals. Since then, a national tourism strategy has been published and changes in legislation have further empowered local authorities to further progress the sustainability agenda. This paper examines these developments and the ensuing implications, concluding that significant progress has been made in developing tourism policies at the local level, but that a number of constraints and issues limit the development of New Zealand as a sustainable destination.  相似文献   
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