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31.
Fred R. Kuss 《Environmental management》1986,10(5):637-650
This article reviews some of the more important factors found to influence the susceptibility of plants to trampling impacts associated with recreational use of natural areas. A three-way interaction mediates plant responses to impacts: plant x environment x stress level(s). Plant responses vary in part according to the genetic constitution of the plant, life and growth form, the adaptive flexibility of the plant, and anatomical differences inherent to growth habit and morphology. Other factors that influence plant sensitivities to impacts are the habitat environments in which plants grow, since a number of conditions such as moisture excesses or deficiencies, nitrogen or oxygen starvation, late frosts, etc., cause physiological injury and may increase plant sensitivity to impacts. Among the environmental factors that may increase or lessen plant sensitivities to impacts are soil moisture levels, canopy density, elevation, aspect, microclimate, soil drainage, texture, fertility and productivity. Seasonal influences also bear consideration since environmental changes and phonological and physiological events are mediated by time of year. Stresses are caused by both direct and indirect forms of impact and vary according to season of use, frequency and amount of use, and the type of activity. These interactions are further complicated by evidence that inter- and intraspecific competition, antagonism, and commensalism may influence differences in the sensitivity of plant communities to impacts. 相似文献
32.
Impacts of Recreation Trails on Exotic and Ruderal Species Distribution in Grassland Areas Along the Colorado Front Range 总被引:1,自引:0,他引:1
This study examines the establishment patterns of exotic and ruderal species along trail corridors in grassland areas of the Colorado Front Range. The effects of trail presence, trail age, and trail traffic levels on exotic and ruderal species establishment are explored to ascertain the potential impacts of trails on surrounding vegetation. Established trails exhibited a greater presence of exotic and ruderal species along the immediate trailside, showing that disturbed trailsides tend to encourage the growth of these species over time. Furthermore, the established trails exhibited significantly less native, nonruderal, and overall species richness at the trailside. These trailside patterns did not show a significant spread away from the trail edge, even after prolonged time periods. Finally, higher trail use tended to hasten the establishment of exotic species along the trailside. The trails did not introduce new species to the recreation areas; rather they acted as reorganizational tools for species that were already present in the study sites. 相似文献
33.
P. Kutiel 《Journal of Coastal Conservation》2001,7(2):183-192
The aims of this study are to review the current situation of the Israeli Mediterranean coastal sand dunes, to examine the
causes for this situation, and to propose options for future conservation and management of the protected dune areas based
on ecological, environmental, landscape and recreational demands and interests. The coastal dunes of Israel are characterized
by diverse plant communities, with 173 plant species occurring on sand (8.2% of the total flora of Israel) including many
endemic species (26% of all endemic species in Israel). Most of the species are annuals. The importance of the coastal strip
as a centre of floral and faunal speciation is also manifested in the existing sand-bound animals. However, many species are
rare. This is mainly due to the extensive industrial and urban development along the coastal plain and the direct and indirect
destruction of the remaining open dune areas by tourism, recreation and sand mining. Only ca. 17% of the Israeli coastal dunes
are still of good or reasonable ecological value, while < 5% of this area has been designated as protected area. Management
policies differ from place to place and depend on local objectives. These objectives derive mainly from the knowledge and
data that exist for each location, and its statutory status. Since 1995 several projects, which aim to develop integrated
management tools for nature conservation and recreation uses for all coastal sand dunes in Israel have been conducted. These
projects are summarized in the present paper. 相似文献
34.
Recreation demand analysis under truncation, overdispersion, and endogenous stratification: an application to Gros Morne National Park 总被引:2,自引:0,他引:2
Using on-site survey data from Gros Morne National Park in Newfoundland, this paper estimates and compares several truncated count data models of recreation demand. The selected model accounts not only for the truncated and overdispersed nature of the data but also for endogenous stratification due to the oversampling of avid users. Moreover, the model that allows for a flexible specification of the overdispersion parameter dominates on the basis of goodness of fit. The results are used to estimate the users' value of access to the park. 相似文献
35.
Visitor use surveys and water quality data indicates that high visitor use levels of two rivers in Puerto Rico does not appear
to adversely affect several water quality parameters. Optimum visitor use to maximize visitor defined satisfaction is a more
constraining limit on visitor use than water quality. Our multiple regression analysis suggests that visitor use of about
150 visitors per day yields the highest level of visitor reported satisfaction, a level that does not appear to affect turbidity
of the river. This high level of visitor use may be related to the gregarious nature of Puerto Ricans and their tolerance
for crowding on this densely populated island. The daily peak visitation model indicates that regulating the number of parking
spaces may be the most effective way to keep visitor use within the social carrying capacity. 相似文献
36.
It is difficult to make general recommendations that apply to all ecosystems. There is still a relative dearth of studies
that allow the manager or visitor to come up with specific practices that are the best for their area. The preferred method
of disposal remains to dig a small hole (cat hole) and bury the waste. Other site specific methods are also discussed.
Treatment of drinking water has become standard practice for most backcountry travel. With such treatment, there is little
evidence currently to suggest that the health hazard to humans is great enough to impose further regulation in areas currently
using cat holes. 相似文献
37.
Christopher A. Monz Kevin J. Gutzwiller Vera Helene Hausner Mark W. Brunson Ralf Buckley Catherine M. Pickering 《Ambio》2021,50(3):631
Disturbance to ecosystems in parks and protected areas from nature-based tourism and recreation is increasing in scale and severity, as are the impacts of climate change—but there is limited research examining the degree to which these anthropogenic disturbances interact. In this perspective paper, we draw on the available literature to expose complex recreation and climate interactions that may alter ecosystems of high conservation value such that important species and processes no longer persist. Our emphasis is on ecosystems in high demand for tourism and recreation that also are increasingly experiencing stress from climate change. We discuss the importance of developing predictive models of direct and indirect effects, including threshold and legacy effects at different levels of biological organization. We present a conceptual model of these interactions to initiate a dialog among researchers and managers so that new research approaches and managerial frameworks are advanced to address this emerging issue. 相似文献
38.
The National Park Service, like other natural resource management agencies, has adopted the traditional model of public administration,
which emphasizes efficiency, effectiveness, economy, and dichotomy between politics and administration. This approach is particularly
ineffective in greenline parks and increasingly inappropriate in traditional areas. In an era of ecological interdependence,
relationships with other agencies and jurisdictions and with adjacent as well as noncontiguous landowners are as important
as controlling visitors. Recreation managers need to develop more skill in negotiation, cooperation, coordination, and interpersonal
communication if they are to preserve and protect park resources. 相似文献
39.
40.
Experimental trampling trials using a standardized methodology were undertaken in 10 replicate blocks in three vegetation types in an urban reserve in the subtropics of Australia. In each block different intensities of trampling (controls, 10, 25, 50, 100, 150, 200, 250, 300, 400 and 500 passes) were applied, and vegetation parameters were measured pre-trampling, immediately after trampling and 2 weeks later. A Fern understorey had low resistance to trampling intensity, with reductions in relative vegetation height and cover with as few as 10 passes. A Tussock grass understorey showed moderate resistance with reduction in height at 25 passes and cover at 50 passes. A Disturbed grassland dominated by lawn grasses had the highest resistance, with reductions in vegetation height at 100 passes, but cover was affected by as few as 10 passes. The resistance indices (number of passes required to reduce vegetation cover by 50%) of three vegetation types were 210, 360 and 860 passes, respectively. When these values were compared with those for 52 other vegetation types considerable variation was found within life forms, climatic zones and vegetation types indicating that the response of a specific community may not always be predictable. 相似文献