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61.
N = 406), highlight some important issues concerning the design and management of wildland recreation environments that are
primarily used for mountain biking. For example, bikers were found to significantly prefer water bars above all other tested
soil erosion management techniques; trail erosion factors, including the presence of rocks, roots, and gullies, all added
to biking experiences on average; trail design factors, such as the presence of turns, bumps, jumps, and obstacles, all added
to biking experiences in general. These findings were used to address questions that resource managers should consider when
striving to effectively manage wildland recreation areas primarily used for mountain biking. 相似文献
62.
Alan Ewert 《Environmental management》1990,14(2):179-184
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
63.
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
64.
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
65.
Application of the wilderness travel simulation model to the Appalachian Trail in Vermont 总被引:1,自引:0,他引:1
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
66.
Kenneth A. Baerenklau Bill Provencher 《Journal of Environmental Economics and Management》2005,50(3):617-636
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
67.
宋相承 《中国特种设备安全》2014,(12):41-42
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.
Twenty Years of Change on Campsites in the Backcountry of Grand Canyon National Park 总被引:1,自引:1,他引:0
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.
The impact of measurement assumptions upon individual travel cost estimates of consumer surplus: a GIS analysis 总被引:1,自引:0,他引:1
I. J. Bateman J. S. Brainard A. A. Lovett G. D. Garrod 《Regional Environmental Change》1999,1(1):24-30
The individual travel cost method is one of the most commonly applied approaches to estimating the recreational value (or
`consumer surplus') of open-access sites where the visitor does not have to pay an entrance charge for using the area. This
paper presents a simple application of the method conducted using geographical information system (GIS) software. This approach
permits analysis of the impact of various, commonly used, assumptions concerning the definition of visitor outset origins
and routing to recreation sites. Results suggest that varying these assumptions can lead to substantial impacts upon estimates
of consumer surplus to the extent that previously published studies may be subject to substantial error.
Received: 24 February 1999 · Accepted: 9 June 1999 相似文献
70.
City dwellers'' accessibility of urban green spaces (UGS) has recently gained immense interest in research and policy. Related scientific studies thus far have focused primarily on spatial distances, largely missing considerations of UGS qualities. We analysed the entire UGS setting of Hannover considering the recreational nature quality and potential demands to identify age-appropriate green spaces by applying a geographic information system analysis of several data sets. Additionally, we assessed the accessibility of UGS for different age groups, varying recreational nature qualities, and potential demands. Results indicate that children and elderly people have poor access to UGS that offers age-related requirements to enable unrestricted nature-based recreation. Nature quality and age-related requirements play a significant role in the assessment of UGS for recreation and accessibility. We conclude that detected vulnerabilities regarding age-related recreation in cities are anchors to mainstream the issue and enhance future planning practices and research.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01808-x. 相似文献