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61.
Mount St. Helens provides an interesting case study of a forest and wildland area that has been radically altered in recent history. As a result of volcanic activity, the recreation environment has changed with respect to the setting, climbing opportunities, and motivations for mountaineering. An evaluation process using both qualitative and quantitative methods was developed to determine what the motivations, demographic characteristics, and preferred management techniques were for the posteruption Mount St. Helens mountain-climbing visitor. Results suggest that changes have occurred in the “new” or posteruption climbing visitor. These changes have not all been congruent with those anticipated by management. For example, the climbing visitor is now less interested in climbing opportunities and more concerned with seeing the crater and other volcanic-related features. This article discusses the findings of this research in light of how resource managers might consider the issue of visitor changes in both demands and types of uses. For example, determining quota numbers based on sociological determinants (e.g., desire for solitude) need to be firmly grounded in who the visitors actually are rather than who they were. Consequently, management tools such as the Recreational Opportunity Spectrum (ROS) and Limits of Acceptable Change (LAC) may need to be altered to accommodate a changing resource or visitor base. These and other findings have implications for the future management practices of the Mount St. Helens area and other environments where the recreation resources have undergone rapid and profound change.  相似文献   
62.
Ecological impacts on camp and picnic sites were examined in three National Park Service units along the Delaware and New rivers, in the eastern United States. All sites experienced pronounced impact to trees, groundcover vegetation, and soils. The nature and magnitude of impacts in these riparian forests were quite similar to those reported in wilderness areas in the mountainous western states and northern Minnesota, despite more favorable growing conditions. The relationship between amount of use and amount of impact and the importance of differences in type of use and environment were also roughly comparable. High-use sites were more heavily impacted than low-use sites, but differences were small when compared with differences in amount of use. The areal extent of impact was the major difference between sites in different environments and sites used by different clienteles. This suggests that the effectiveness of basic strategies for managing impact should not differ greatly between regions. Here, as elsewhere, actions taken to control the areal extent of impact appear to be particularly important.  相似文献   
63.
This article describes three applications of the Universal Soil Loss Equation for further defining differences between natural environments in terms of their suitabilities for recreation use. Physical capacity limits based upon vulnerability to erosion and loss of soil productivity are discussed. Examples include: (a) applications to site planning and comparison of existing campsites; (b) use of the methodology for setting limits of acceptable change; and (c) characterization of third-order or larger watersheds that compare ecological land type interpretations with those based upon application of the equation.  相似文献   
64.
The wilderness travel simulation model estimates complex recreation use patterns in park and wilderness environments. The model was applied to a section of the Appalachian Trail in Vermont, a linear, long-distance, multiple-access trail system characteristic of the eastern United States. Many portions of the trail, including the study area, are now experiencing high use. The model estimated the average number of trail encounters per party day to be 3.3 and the average number of camp encounters per party night to be 2.3. Other measures of recreation use were also estimated that should prove useful to trail management and administration. Three trail management scenarios were tested, providing several preliminary insights to managers: the desirability of use redistributions as opposed to across-the-board reductions and needed emphasis on spatial use patterns and campsite encounters. Only minor modifications to the program were needed in applying the model to the trail environment and the model functioned accurately according to the validity tests performed.  相似文献   
65.
This paper examines the consequences of using a static model of recreation trip-taking behavior when the underlying decision problem is dynamic. Specifically we examine the implications for trip forecasting and welfare estimation using a panel dataset of Lake Michigan salmon anglers for the 1996 and 1997 fishing seasons. We derive and estimate both a structural dynamic model using Bellman's equation, and a reduced-form static model with trip probability expressions mimicking those of the dynamic model. We illustrate an inherent identification problem in the reduced-form model that creates biased welfare estimates, and we discuss the general implications of this for the interpretation of preference parameters in static models. We then use both models to simulate trip taking behavior and show that although their in-sample trip forecasts are similar, their welfare estimates and out-of-sample forecasts are quite different.  相似文献   
66.
The study consists of two parts. One part deals with recreation and vacation demands; the other investigates the relationship between recreation demand and some natural landscape elements preferred in the eastern Black Sea coastal zone of Turkey, which has traditionally a rich recreational culture. Home interview surveys were conducted during the summer of 1992. The recreation demand of the study area has been found to be 89.3% including potential demand. The landscape element "sea and seaside" preferred for recreation has been rated the highest in all groups of each of the five variables, namely, age, education, income, occupation, and marital status. The research reported here represents an empirical contribution to the field of landscape preference studies for recreation, especially in the developing countries.  相似文献   
67.
特种设备作为危险性较大的工业、民用设备,其发生事故所造成的影响,远远大于一般设施。保险作为消化风险、分化补偿的重要方式,尚未与特种设备建立起完善的事故责任保险制度。本文通过国内外相关制度的比较,探讨建立该制度的必要性及社会的迫切需求。  相似文献   
68.
This article draws on three separate research and monitoring studies to describe 20-year trends in the number and condition of campsites in the backcountry of Grand Canyon National Park. Results are used to assess the effectiveness of a complex and innovative management program, adopted in 1983, that sought to concentrate use on designated campsites in popular places and disperse camping in more remote places. In 1984, conditions on 12 high-use campsites and 12 low-use campsites were carefully assessed. Conditions on 22 of these campsites were reassessed in 2005. In addition, campsite-monitoring surveys were conducted between 1985 and 1992 and again in 2003 and 2004. In these surveys, all campsites were located and their condition rapidly assessed. The detailed assessment of a sample of sites suggests relatively little change in condition during the 20-year period. The high-use sites were more highly disturbed than the low-use sites, but they did not change more during the study period. In contrast, changes at larger scales were dramatic. The total number of campsites more than doubled during the study period. Surprisingly, the proliferation of new campsites was greater in places where camping was only allowed on designated campsites than in places where camping was allowed anywhere. Concern that concentration of use on designated sites would cause unacceptable impact was unfounded. Management implications for other internationally significant protected areas that allow backcountry camping are explored.  相似文献   
69.
70.
Urban green spaces provide important recreational services for urban residents. In general, when park visitors enjoy “the green,” they are in actuality appreciating a mix of biotic, abiotic, and man-made park infrastructure elements and qualities. We argue that these three dimensions of structural diversity have an influence on how people use and value urban parks. We present a straightforward approach for assessing urban parks that combines multi-dimensional landscape mapping and questionnaire surveys. We discuss the method as well the results from its application to differently sized parks in Berlin and Salzburg.  相似文献   
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