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81.
通过对我国大型游乐设施的发展概况、风险管理现状、危险因素辨识、风险评价和风险控制等五个方面进行了分析总结.研究发现,目前已初步建立游乐设施法规体系,逐渐形成了法律、法规、规章、安全技术规范和技术标准的五层次体系,大型游乐设施运营单位安全管理正在向标准化、体系化管理方向发展.我国还没有对各类大型游乐设施进行危险性分析,有关标准和规范中并没有提到明确的风险分析和评估方法,在游乐设施的设计、制造、安装、使用、改造、修理和检测过程中也没有形成一套系统、科学的风险分析和评估方法. 相似文献
82.
/ The management of lands adjacent to federally designated wilderness is increasingly seen to have the potential to negatively impact wilderness resources and management objectives. This paper first examines the numerous and often conflicting laws and regulations that influence how managers can mitigate transboundary issues. We then examine the various types of transboundary issues, and describe how they impact wilderness resources. Transboundary issues include recreational use, extractive activities, fire management, exotic species introductions, aircraft overflights and military operations, water diversion, urban encroachment, and transported pollutants. KEY WORDS: Adjacent lands; Buffer zones; Ecosystem management; Wilderness; Zones of influence 相似文献
83.
Fast economic and social changes in recent years in China have brought massive expansion, redevelopment, and restructuring
of cities. These changes offer cities the opportunity to improve environmental quality through urban green spaces (UGSs) and
to address the challenges of meeting community aspirations. This study explored peoples’ minds concerning UGSs in Guangzhou
city in south China in relation to the following: (1) knowledge and perception of 25 ecosystem services and 8 negative impacts;
(2) attitude toward site condition and management; (3) expectation of landscape design; and (4) preference ranking of venues.
A questionnaire was designed to solicit opinions from 340 respondents randomly chosen from residents living in the study area.
The results indicated widespread recognition of ecosystem services and strong support of UGS programs. Negative responses
were weakly expressed. Amelioration of urban microclimate and environmental quality were emphasized. Environmental functions
stressed in publicity programs, together with aggravating environmental problems in the city, tended to focus respondents’
attention on UGS benefits. Wildlife habitat, species conservation and other natural ecosystem services drew limited concerns.
Awareness of economic benefits was very low. Visual-landscape contributions with strong preference for naturalistic design
and recreational benefits were highlighted. Compared with other countries, Guangzhou residents were characterized by visual–scenic–recreation
orientation and pragmatic–utilitarian perception of UGSs, reflecting underlying differences in the understanding of inherent
ecosystem services of green spaces. Relevant UGS policies and practices could adopt the approaches of market survey, citizen
participation, and precision planning in order to meet increasingly mature and refined demands. Citizens’ understanding of
high-order ecosystem services could be enhanced to encourage appreciation of nature and their associated benefits. 相似文献
84.
After 50 years of steady increase, per capita visits to US national parks have declined since 1988. This decline, coincident with the rise in electronic entertainment media, may represent a shift in recreation choices with broader implications for the value placed on biodiversity conservation and environmentally responsible behavior. We compared the decline in per capita visits with a set of indicators representing alternate recreation choices and constraints. The Spearman correlation analyses found this decline in NPV to be significantly negatively correlated with several electronic entertainment indicators: hours of television, (rs=-0.743, P<0.001), video games (rs=-0.773, P<0.001), home movies (rs=-0.788, P<0.001), theatre attendance (rs=-0.587, P<0.025) and internet use (rs=-0.783, P<0.001). There were also significant negative correlations with oil prices (rs=-0.547, P<0.025), foreign travel (rs=-0.452, P<0.05), and Appalachian Trail hikers (rs=-0.785, P<0.001). Income was significantly positively correlated with foreign travel (rs=0.621, P<0.005) but negatively correlated with national park visits (rs=-0.697, P<0.005). There was no significant correlation of mean number of vacation days, indicating available vacation time is probably not a factor. Federal funding actually increased during this period, and so was rejected as a probable factor. Park capacity was rejected as limiting since both total overnight stays and visits at the seven most popular parks rose well into the mid-1990s. Aging of baby boomers was also rejected as they are only now reaching retirement age, and thus during the period of visitation decline were still of prime family vacation age. Multiple linear regression of four of the entertainment media variables as well as oil prices explains 97.5% of this recent decline (r=0.975, multiple r2=0.950, adjusted multiple r2=0.925, SE=0.015, F=37.800, P<0.0001). We may be seeing evidence of a fundamental shift away from people's appreciation of nature (biophilia, Wilson 1984) to 'videophilia,' which we here define as "the new human tendency to focus on sedentary activities involving electronic media." Such a shift would not bode well for the future of biodiversity conservation. 相似文献
85.
Public parks are important to urban environments, residents, and visitors. Among other functions, they provide environmental services, such as air and water purification, and they increase both recreational opportunities and the attractiveness of the urban environment. Because of their importance, urban parks serve as public spaces that provide visitors and urban residents with rights to the city. This paper identifies the dearth of urban public parks in Accra-Tema city-region as worrying. The Accra Plan 1958 underscored the significance of green spaces and designated the coastal strip for parks development but the areas have been lost to various urban uses. We argue that the continual neglect of public parks within urban planning and community development schemes in the Accra-Tema city-region is a major concern because it is depriving the citizens a right to the city and its public spaces. A number of factors have worked adversely against the provision of public parks and green spaces in the city-region. These include development pressures, undue political interference, a complex land delivery system, and ad hoc planning. The paper concludes by offering policy suggestions as to how to resolve the dearth of parks and green spaces in the city-region. 相似文献
86.
Daniel H. Henning 《Environmental management》1987,11(3):283-293
This article deals with wilderness politics in relationship to values and public participation; these terms are defined for the purpose of the study. It is argued that the survival, quantity, and quality of wilderness everywhere will basically be determined by the political and governmental processes through values. Yet there is a strong tendency in these processes to avoid value exposure and emphasis.Much of governmental approach toward wilderness affairs hinges upon economic development, technoscientific facts, and short-term considerations, in contrast to the intangible noneconomic and long-term values of wilderness. By not articulating nd involving wilderness values more in public participation and the political processes, the public often misses opportunities for influencing far-reaching wilderness decisions. In short, wilderness values need to be more explicitly and implicitly stated and implemented politically.More study and emphasis need to be given to wilderness values per se. It is necessary to develop more innovative ways of educating the public on wilderness values in terms of their lives and of ensuring that their value inputs are effectively incorporated into public participation and political processes. The last section of this article is devoted to efforts by the author and others to identify and describe wilderness tropical forest values. 相似文献
87.
ABSTRACT: This paper details the increasing tendency to overdevelop lands adjacent to public reservoirs. The impact on water quality of the pollutant load carried in surface runoff from developed lands is described as well as the depreciation in recreational experience due to loss of scenic horizons. The case study, Spruce Run Reservoir in Clinton, New Jersey, included population and demand projections. Land speculation and proposed development are evaluated on a physical constraint basis. Areas of conflict are outlined and conflict resolutions proposed. 相似文献
88.
Roger H. von Haefen Daniel J. Phaneuf 《Journal of Environmental Economics and Management》2003,45(3):612-630
Continuous and count data demand system models have emerged as attractive alternatives to the discrete choice random utility maximization models (RUMs) that currently dominate the seasonal, multi-site recreation demand literature. This paper compares the frameworks conceptually and investigates their empirical performance with a common data set. Although the two modeling approaches employ substantially different behavioral and econometric assumptions, results from a recreation application based on the 1997 Iowa Wetlands Survey suggest that qualitatively similar policy inferences arise from the competing structures. 相似文献
89.
多目的地环程旅行问题是应用旅行费用法(TCM)进行游憩价值评估的难点和热点,客观准确地对多目的地旅行公共费用进行分成,确定各目的地的费用权重成为游憩价值评估的关键性问题。因此,本文引入旅行公共费用和目的地直接费用的概念,改进多目的地旅行公共费用分成计算模型,将待评估目的地直接费用与多目的地总直接费用的比值作为待评估目的地在旅行公共费用中的分成权重。该计算模型尝试根据调查游客自身的消费特点进行旅行公共费用分成,避免主观假设的影响,旨在使费用分成更加客观、科学。对若尔盖县游憩价值的评估结果为:2017年若尔盖县游憩价值为31.09亿元,人均游憩价值1538元;其中旅行费用 25.06亿元,人均旅行费用1240元;消费者剩余6.03亿元,人均消费者剩余298元。通过改进多目的地旅行费用分成模型,可推动游憩价值评估方法的发展和完善。研究结果可为若尔盖县生态旅游产业发展规划提供科学指导。 相似文献
90.
Surface disposal of human waste by the smear method, a suggested but heretofore unexamined technique, was tested in three environments and examined for reductions in fecal mass and fecal indicator bacteria. Substantial reduction in fecal mass was observed after six and fourteen weeks of exposure in all environments, but extensive reduction in fecal indicator bacteria was observed in only the arid and alpine environments. Although surface smears appear favorable to cathole techniques in terms of indicator bacteria reduction, the application of this method is limited by several other factors common to backcountry sanitation situations. It is therefore likely that surface disposal would only be applicable in very remote, low use, alpine and arid settings where lack of soil development precludes the use of catholes and carry-out techniques are otherwise impractical. 相似文献