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81.
External threats to the environmental integrity of Glacier National Park, Montana, USA, fit into three categories: adverse land use practices adjacent to the Park, air pollution, and water pollution. This article identifies and evaluates the laws that Glacier National Park officials might rely upon to protect the Park against these external threats. The article also assesses the available scientific information relating to external threats, and it identifies additional information needed to establish a legal basis for challenging the threats. 相似文献
82.
Recreational impacts on backcountry campsites in Grand Canyon National Park,Arizona, USA 总被引:2,自引:0,他引:2
Backcountry campsites were studied in three desert vegetation types (pinyon-juniper, catclaw, and desert scrub) in Grand Canyon National Park, Arizona. Relationships between amount of use and amount of impact were examined within each vegetation type. The area disturbed was small, but impacts were generally severe. Important impacts were increased soil compaction and associated decreases in infiltration rates and soil moisture content; these were substantially more pronounced on high than low use sites. The only impact parameter that differed significantly between vegetation types was core area. The types of impact identified are similar to those found in the coniferous forests studied elsewhere, as is the logarithmic relationship between amount of use and amount of impact. However, Grand Canyon sites can support more visitor use before reaching near-maximum levels of impact for important impact parameters. 相似文献
83.
Park design principles are proposed on the basis of consideration and analysis of rare plant species in Great Smoky Mountains National Park, USA. Rare species richness can be used as a simple measure of preservation success. A semilogartihmic species-area model for the Smokies was used in this analysis. Species richness would increase logarathmically with expansion of the national park area. An analysis of the relationship between species richness and the distribution of geologic and topographic features in the national park was also reported. An asymptotic relation was documented for the accumulation of newly recorded rare and endangered vascular plant species in the Smokies region up to 1978. Several multiple regression linear models predicted rare vascular plant species richness in Great Smoky Mountains National Park from area and topographic variates.Preserve design criteria can be based upon species-area, environmental gradient, and natural features distribution patterns for the specific taxa and biogeographic region under consideration. In addition, natural history characteristics for particular vulnerable species must be assessed. Rather than concentrating on the preservation of undocumented immigration and extinction processes, preserve design should be directed towards protecting geographic components and gradient patterns characteristic of a region. 相似文献
84.
Robert J. Langridge Bryan D. MacGregor 《Journal of Environmental Planning and Management》1986,29(1):19-22
This study analyses the behaviour of high technology and new firms in the Newbury District of Berkshire in terms of employment, location, genealogy, and local economic impact. It finds that encouraged by good communications networks and a ‘resident electronics establishment’, the direct, as opposed to the indirect, employment consequences are generally encouraging, but not widely replicable. Moreover, the general picture of employment growth masks important differences in labour demand across occupations, particularly with respect to ‘traditional male’ skilled manual workers. 相似文献
85.
The paper examines characteristics of science parks in the face of employment decline, raising doubts about the scale of their success. The paper re‐examines previous research on the existence and causes of long waves of economic growth and decline and concludes that if these are not generated by innovations in production, then it should not be surprising that science parks have not lived up to expectations. 相似文献
86.
Christopher S. Davies 《Environmental management》1988,12(4):479-490
Industrial dereliction is a concern to all societies. In the United Kingdom the British government is trying to make its abandoned coalfields more attractive to new industry through a combination of land reclamation and job incentive programs. The most ambitious of these projects occurs in the South Wales Coalfield, which records 200 years of land defilement and the highest unemployment amplitudes in mainland Britain. In returning this area to a semblance of its previous state, problems arise over how best to fill and cap the many derelict pit shafts and abandoned shallow mines that riddle this region. This analysis reports on the methods of treatment used to achieve this end, along with the procedures used to minimize ground subsidence, water pollution, noxious gas emission, and the potential for physical injury. These environmental controls have application to the United States and Western Europe, where pockets of industrial blight are also symptomatic of a troubled local economy. 相似文献
87.
S. Cameron 《Journal of Environmental Planning and Management》1983,26(2):75-79
The paper examines changing approaches to local economic development in the period since 1974. Initially, it proposes an ‘orthodox’ model of local economic development policies which emphasised the provision of a better industrial fabric, and of financial assistance to small, inner city firms. It suggests three recent directions of change in emphasis from this orthodox model: help in the creation of new entrepreneurs; replacement of public sector by private sector action; local authority shareholding in local firms by use of Enterprise Boards. Each approach makes different assumptions about the public/private sector relationship, the last two involve a more explicitly ideological stance on this issue. 相似文献
88.
夏秋蚕病是北方蚕桑生产上存在的主要问题,对蚕桑的危害不断扩大。为此,笔者根据多年调查研究,试验摸索出了北方蚕区夏秋蚕病的防范对策。 相似文献
89.
Human impacts on the stream-groundwater exchange zone 总被引:13,自引:0,他引:13
Hancock PJ 《Environmental management》2002,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers
create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers
and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses
on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining,
agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota
and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems.
Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river
management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic
zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human
activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches
of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic
zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic
restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments,
maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献
90.
Benefits-based management seeks to provide recreation benefits for recreation participants by managing the physical environments
in which recreation occurs. This study investigates the relationship between benefits desired by visitors and the physical,
social, and managerial characteristics of settings that facilitate realization of recreation benefits. Data such as perceived
benefits from recreation experiences, setting attributes that significantly influenced perceived benefits, and sociodemographic
variables were collected from 376 visitors to Sorak-san National Park in the eastern part of the Korean peninsula. Cluster
analysis was used to group visitors' desired benefits into 12 domains: relationship with nature/scenery, escaping pressure,
learning about nature, family togetherness, introspection, exploration, autonomy/achievement, being with friends, leading
others, skills/learning, risk taking, and meeting/observing new people. Multiple regression was used to link benefit domains
with the characteristics of settings. The social attribute of recreation settings was linked to eight of the ten benefit domains.
There were two statistically strong multiple regression correlations: (1) between domain of “relationship with nature /scenery”
and the attributes “forest/water,”“attractive nature,” and “facility/maintenance” and (2) between the domain of “escaping
pressure” and the attributes “attractive nature” and “social.” The results of this study are useful to managers in their efforts
to provide recreation opportunities for visitors to achieve beneficial outcomes. 相似文献