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81.
Sociological edge effects: Spatial distribution of human impact in suburban forest fragments 总被引:4,自引:0,他引:4
Glenn R. Matlack 《Environmental management》1993,17(6):829-835
Suburban forest fragments often experience heavy recreational and waste disposal use, with considerable damage to the vegetation.
To suggest strategies for conservation of the forest flora, spatial distributions of human impact were described in 40 fragmentary
stands in northern New Castle County, Delaware. The distribution of human impact showed a significant bias to the forest edge,
with 95% of localized damage occurring in the first 82 m. Forms of impact related to lawn maintenance fell significantly closer
to the edge than impacts related to recreation and showed the strongest edge orientation. Edge distances of campsites, vandalized
trees, and firewood gathering were negatively correlated with distance to the nearest graded road, indicating the importance
of road access. Several forms of impact were also clustered near footpaths, although distance to paths was independent of
edge distance in all cases. In terms of penetration of the forest and severity of damage, human impact greatly exceeds natural
edge effects reported for this community. These findings suggest that damage may be minimized by limiting road access and
avoiding the creation of small forest fragments. 相似文献
82.
The Arctic is subject to considerable pressure from a rapidly expanding world tourism industry and increasing demands for
oil and gas resources. The archipelago of Svalbard in the Norwegian high arctic contains the most accessible islands in the
entire Arctic, but despite extensive use of the resources, they still contain some of the last true wilderness lands in Europe.
The growth in tourism with visitors from all parts of the world combined with coal mining and oil and gas exploration call
for a coordinated environmental policy. A research-based management plan for tourism and recreation has now been developed.
Some management problems were encountered in designing a recreation opportunity spectrum plan for this extremely vulnerable
environment. Although Svalbard in many ways is a unique area, the challenges to management are comparable to those found in
regions further south. 相似文献
83.
We quantified spatial dynamics and substrate impacts of snorkelers and SCUBA divers within four Hawaiian MPAs to determine:
(1) whether coral reefs in these areas are being damaged by recreational activities, and (2) how damage might be mitigated.
Observers secretly followed snorkelers and SCUBA divers, and used handheld Global Positioning System (GPS) units to record
their geographic tracks and substrate contacts. Most activities occurred within relatively small, well-defined areas associated
with access points. Despite heavy use, recreation impact was low at Hawaiian MPAs because most fragile corals occurred below
the maximum depth of the dominant recreational activity (snorkeling). SCUBA diving was only common at one MPA with physically
durable benthic habitats. GPS tracking provided useful insights into how recreational impacts to MPAs could be reduced. General
topography could be used to predict where visitors will go, and designated access points could be used to focus substrate
contact away from fragile habitats. 相似文献
84.
The opportunity Value of Travel Time (VTT) is one of the most important elements of the total cost of recreation day-trips and arguably the most difficult to estimate. Most studies build upon the theoretical framework proposed by Becker (1965) by using a combination of revealed and stated preference data to estimate a value of time which is uniform in all activities and under all circumstances. This restriction is relaxed by DeSerpa's (1971) model which allows the value of saving time to be activity-specific. We present the first analysis which uses actual driving choices between open access and toll roads to estimate a VTT specific for recreation trips, thereby providing a value which conforms to both Becker's and DeSerpa's theoretical models. Using these findings we conduct a Monte Carlo simulation to identify generalizable results for subsequent valuation studies. Our results indicate that 3/4 of the wage rate provides a reasonable approximation of the average VTT for recreation trips, while the commonly implemented assumption of 1/3 of the wage rate generates downward biased results. 相似文献
85.
In the last few decades, trampling has become a cause of major disturbance to natural areas. Trampling can occur regularly either seasonally or throughout the year, or as a single impact depending on a recreational activity or an event. This study, carried out on a coastal heathland in north Brittany (France), was based on the hypothesis that the vegetation response can differ depending on whether the trampling is repeated or due to a single event. The aim was to compare the resistance and the short-term recovery capacity of selected species in coastal heathland communities subjected to a trampling experiment, applied once or five times (with equal total number of passes from 0 to 800). The temporal distribution of the trampling did not affect the response of Erica ciliaris, whereas for Erica cinerea and Ulex gallii, trampling was slightly less damaging when applied once rather than five times. These differences could be linked to the lower resistance and the higher recovery capacity of E. ciliaris, compared with the two other species. This study also emphasized the influence of site location by comparing observations with previous studies. Plant resistance calculated here appeared to be lower than that calculated for a less stressful site. The relationship between plant traits and response to trampling was also investigated. The effects of the different times between disturbance application and observations of the short-term response of woody vegetation to experimental trampling is also discussed. 相似文献
86.
基于虚拟样机技术的游乐设施安全分析方法探讨 总被引:5,自引:4,他引:1
游乐设施安全问题日益受到人们的关注。笔者介绍了虚拟样机技术的产生及其发展情况 ,并对两种主要虚拟样机应用软件 (ADAMS软件和SIMPACK软件 )进行了比较。根据目前国内游乐设施安全问题的实际情况 ,提出了应用虚拟样机技术解决该问题的重点和难点 .在充分分析的基础上 ,结合ADAMS软件论证了应用虚拟样机技术解决游乐设施安全问题的可能性 ,提出了初步的解决方法。为进一步将此方法应用于实际奠定了理论基础。 相似文献
87.
Impact of Fencing on the Recovery of the Ground Flora on Heavily Eroded Slopes of a Deciduous Forest
This paper seeks to outline early stages in the recovery of forest ground flora on eroded slopes impacted by recreation activities and to suggest how these data might be applied in the formulation of management policies for forest recreation areas. Based on a fencing experiment in the Sonian Forest near Brussels, we investigated whether, over a 6-year period, the vegetation was able to recover after having been destroyed by recreation use. Short-term trends in overall species composition were already observable during this 6-year study. Species recovery on eroded hills was related to slope, aspect, and soil type. During the considered time scale, the proportion of hemicryptophytes and the number of ancient forest species increased significantly. A downward trend was detected for Ellenbergs nitrogen and temperature indexes and for the proportion of therophytes and pioneer plants of disturbed places. Changes in species frequencies suggest six recovery strategies: early, late, expanding, disappearing, transient, and fluctuating species. Aside from seedling reproduction from overstory influences, Luzula sylvatica appeared to be the most resilient of the species identified in the study since this species has the highest global frequency in our sampling plots and has increased its cover during the study period. Study results indicate that (1) protection from recreation has initiated the recovery of species in the herb layer, but (2) it may take a long time before vegetation previously present in the ground flora may recover in both density and species composition. 相似文献
88.
Influence of Social, Biophysical, and Managerial Conditions on Tourism Experiences Within the Great Barrier Reef World Heritage Area 总被引:1,自引:0,他引:1
N = 1475) traveling with tourism operations of different sizes who traveled to different sites completed surveys. Results indicated
that snorkelers who traveled with larger operations (more people and infrastructure) differed from those traveling with smaller
operations (few people and little on-site infrastructure) on benefits received and in the way that specific conditions influenced
their enjoyment. Benefits related to nature, escape, and family helped to define reef experiences. Conditions related to coral,
fish, and operator staff had a positive influence on the enjoyment of most visitors but, number of people on the trip and
site infrastructure may have the greatest potential as setting indicators. Data support the potential usefulness of visitor
input in applying the LAC concept to a marine environment where tourism and recreational uses are rapidly changing. 相似文献
89.
Colin Price 《Environmental management》1981,5(2):161-175
Overuse of recreation sites seems to justify regulation, and the principal tools for this are fee charging or physical exclusion. Both seem equally costly to administer. Both involve equal costs to consumers if recreationists visit from one origin, but if they come from different origins, costs may be greater and consumers' surplus less under either tool, depending on the shape of the demand curve. Which is the more equitable tool depends on the relative representation of rich and poor participants from near and distant origins. Potentially beneficial use of site revenues is an advantage of charging. Neither availability of substitutes nor variation in daily demand seems likely to change these results substantially, but a system of booking admissions before the trip outset might neutralize the advantages of charging. The optimal level of use varies with the regulatory tool chosen. The optimal admissions under exclusion could be fewer than or more than under charging, or may even be equal to unregulated use. 相似文献
90.
Recreation use was studied on a diverse state river system to test the hypothesis that recreation use patterns vary systematically by river type. River segments were classified into representative river types through application of a two-fold classification system. The first classification factor, generalized geomorphology, defines and groups the dominant resource bases of which rivers are comprised. The second classification factor, cultural setting, defines the land use and settlement patterns in which each river type is found. Significant differences were found among resulting river types with respect to the nature and intensity of recreation activity, desired use density, and user perceived problems and conflicts. Management recommendations were developed, based on study findings, for each river type. It is concluded that when both environmental attributes and cultural setting are taken into account, regularities appear with respect to the way in which river resources are used and perceived by recreationists. Further exploration and expansion of such recreation-resource relationships to other activities and environments may hold substantial implications for the allocation and management of outdoor recreation resources. 相似文献