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1.
Naturalness In Biological Conservation   总被引:1,自引:0,他引:1  
Conservation scientists are arguing whether naturalness provides a reasonable imperative for conservation. To clarify this debate and the interpretation of the term natural, I analyze three management strategies – ecosystem preservation, ecosystem restoration, and ecosystem engineering – with respect to the naturalness of their outcomes. This analysis consists in two parts. First, the ambiguous term natural is defined in a variety of ways, including (1) naturalness as that which is part of nature, (2) naturalness as a contrast to artifactuality, (3) naturalness as an historical independence from human actions, and (4) naturalness as possession of certain properties. After that, I analyze the different conceptions with respect to their implications for the three management strategies. The main conclusion is that there exists no single conception of naturalness that could distinguish between the outcomes of the three management methods. Therefore, as long as the outcomes of the different methods are regarded as being of a different value in conservation, we should either abandon the idea of naturalness as the guiding concept in conservation or use the term natural only in the ways that take both its historical and feature dependent meanings into consideration.  相似文献   

2.
By mid-1990 the National Park Service (NPS) must present to Congress recommendations for managing overflights of at least ten national parks. The authors examine the potential role of formal negotiation in setting overflight policy in these parks by reviewing the overflight controversy at Grand Canyon National Park (GCNP). Regulations controlling overflights of the GCNP are only now being implemented after a 17-year conflict that culminated in a congressionally mandated solution. The authors review this controversy and find that, contrary to common perception, the number of park visitors bothered by overflights is not small but roughly equals the number of airborne visitors (up to 450,000 per year). On the basis of this investigation, the authors determine that formal negotiation would have been an appropriate policy-making process because of the clearly defined and limited number of parties and issues involved. Considering the number of park visitors that will continue to be affected by this issue, the authors conclude that formal negotiations should be considered for overflight problems involving other parks. Such negotiations should be park-specific. Differences in park size, extent of the problem, and parties involved would prohibit park-wide negotiations.This article has been adapted from Tourist Flights over the Grand Canyon: The Potential for Negotiated Solutions to Similar Problems, Analysis and Management, October 30, 1987. The opinions expressed in this article are those of the authors; they are not meant to represent the views of the organizations with which the authors are associated.  相似文献   

3.
The purpose this study was to improve operational planning and management of national parks in Turkey to balance conservation use and sustainable management. Souksu National Park (SNP) was chosen as the study area. The data were obtained from interviews of 182 visitor groups (in total, 819 people) and analyzed using correlation, factor, discriminant, and regression analyses. It was found that the most important factors affecting operational planning and management of SNP are (1) travel cost, (2) visitor welfare level, (3) intensity of use, (4) size of visitor group, (5) type of recreational demand. The main source of visitors to SNP is from a zone within a 0–90-km radius. This region comprised 53.85% of total visitors to the park. The capital of Turkey (Ankara) is the most important source of visitors from within this zone. The optimum activity mix in SNP is also determined. Picnicking, viewing the scenery, and nature walks or trekking comprised the main uses of the park. It is anticipated that these findings will help to improve operational planning and sustainable management of the national park and the environment.  相似文献   

4.
The management of tropical protected areas is a contentious issue in resource management and often leads to an unproductive polarization of viewpoints supporting either protectionist or sustainable development paradigms. This paper argues for a context-driven approach whereby effective management requires inputs from both paradigms in different situations. A key element of context is understanding long-practiced resource tenures and their ability to meet future conservation and livelihood goals. Different types of tenure arrangements are often required for different resources. This approach is illustrated by analysis of Virachey National Park in NE Cambodia. This park encompasses part of the ancestral territory of ethnic Brao people, who rely upon swidden agriculture, fish, terrestrial wildlife, and various nontimber forest products (NTFPs) for their livelihoods. These people have developed a mix of resource tenure regimes to promote sustainable use and to maximize local benefits. In the face of contemporary pressures, some of these traditional approaches are effective, while others are not. The paper suggests avenues for building on long-established management practices of the Brao to achieve park management goals while enhancing the welfare of the Brao people. A mix of private ownership, common property management, and central government involvement may be required to maximize benefits to local people and ensure long-term protection of biodiversity.  相似文献   

5.
A formal model for the interaction of bear and hiker populations in national parks is developed. A number of alternative interactive scenarios are identified and some specific cases explored in detail. Some examples of the insights to be gained by the use of such a formal structure by park managers charged with the dual mandate of preservation of fauna and provision of safe recreational opportunities are presented. The entire problem is then discussed within the context of the more general tragedy of the commons problem.  相似文献   

6.
Natural resource managers often rely on the advice of specialists to aid decision making. However, disagreement among these specialists about the relative value of particular management objectives or the risks associated with implementing certain management strategies may complicate the decision effort. Multiattribute utility analysis can facilitate decision making by indicating how attributes of a problem are weighed by individual specialists. This information can then be used to outline bands of potential problem solutions that are acceptable to the advising group and may allow management to further its own objectives (possibly increased efficiency).An example is presented that relates to fire management planning efforts on national forests. Multiattribute utility functions developed from a survey of fire management professionals are used to identify utility-maximizing fire management strategies based on each strategy's level of economic efficiency and risk. Bands of utility-indifferent potential solutions are outlined based on measures of group consensus. It is pointed out that a subset of these would further management's goal (increased efficiency) without significantly altering the value assigned to the risk attribute by the specialists. Finally, the robustness of the technique is discussed with particular reference to environmental management problems and the role that proxy information often plays in decision making.  相似文献   

7.
8.
Food habits of white-tailed deer (Odocoileus virginianus) were examined from January to November 1984 via fecal-pellet analysis at Valley Forge National Historical Park (VFNHP), which represents an island habitat for deer surrounded by extensive urbanization, in southeastern Pennsylvania. In addition, use of fields by deer was compared to food habits. Herbaceous vegetation (forbs, leaves of woody plants, and conifer needles) was the predominant food type in all seasons except fall. Acorns and graminoids (grasses and sedges) were important food resources in fall and spring, respectively. Use of woody browse (twigs) was similar among seasons. Field use was relatively high during fall, winter without snow cover (<20 cm), and spring when food resources in fields were readily available. In contrast, use of fields was lowest in summer when preferred woodland foods were available and in winter with snow cover when food in fields was not readily accessible. Patterns of food-type use by deer at VFNHP indicate the year-round importance of nonwoody foods and field habitats to deer populations on public lands such as national parks in the northeastern United States.  相似文献   

9.
New ideas about conserving wildlife are emerging to compete with conventional national park policies. But methods of analyzing wildlife conservation problems in Africa are inadequate for the analysis of complex issues of policy. Much of the analysis of conservation policy attempts to be apolitical on issues charged with social conflict. Analyses are too often ahistorical when history can say a great deal about the origins of present-day ecological problems. Further-more, problems are commonly analyzed within narrow discilinary frameworks which predetermine the nature of conclusions and lead to professionally biased proposals. This case study of the Luangwa Valley, Zambia, is used to demonstrate a method which attempts to remedy these weaknesses,In the first part of the article we examine the role of the Luangwa National Parks in the context of the Zambian political economy, and identify social groups which compete for the resources of the national parks. Next we trace the historical origins of present-day ecological changes. These analyses lead toward a model of the Parks and some of their relationships with the national economy. We end with a proposal for communal use of wildlife which attempts to resolve some of the contradictions inherent in current policy.  相似文献   

10.
The physicochemical characteristics of the recipient environment into which chemical contaminants are deposited may influence their chemical speciation, mobility, bioavailability, and toxicity. In formulating Water Quality Criteria, the Environmental Protection Agency of the United States (EPA) considered the modifying effect of abiotic environmental factors on pollutant toxicity in an innovative regulatory approach. Scientific knowledge of the interactions and correlations between pollutant toxicity and abiotic factors remains limited. Recognition of the influence of the physicochemical characteristics of the recipient environment on pollutant toxicity has implications for the eventual formulation of regional, rather than uniform and national, criteria. In addition, in developing Water Quality Criteria that incorporate the effects of pollutants on aquatic life, EPA primarily focused on toxicity to aquatic animals and plants (including unicellular algae). The effects of pollutants on microbe-mediated ecological processes that are necessary for maintaining the state and quality of the ecosphere (such as biogeochemical cyclings, litter decomposition, and mineralization) were not included in the formulation of the Water Quality Criteria. To facilitate the recognition and quantification of adverse effects of pollutants on these ecological processes, the development of a computation, termed the ecological dosage 50% (EcD50) is recommended. Such a formulation could also be applied to setting environmental quality criteria for terrestrial ecosystems.  相似文献   

11.
Agricultural lands have the potential to contribute to greenhouse gas mitigation by sequestering organic carbon within the soil. Credible and consistent estimates will be necessary to design programs and policies to encourage management practices that increase carbon sequestration. Because a nationwide survey of soil carbon by the wide range of natural resources and management conditions of the United States is prohibitively expensive, a simulation modeling approach must be used. The National Nutrient Loss Database (NNLD) is a modeling and database system designed and built jointly by the USDA– Natural Resources Conservation Service (NRCS) and Texas A&M University to provide science-based inferences on environmental impacts from changes in agricultural management practices and programs at the regional and national level. Currently, the NNLD simulates 16 crops and covers 1.35 × 108 ha. For estimating soil carbon sequestration, the database will be populated with 1.5 × 106 field-level model runs using the EPIC (Environmental Policy Impact Calculator) model, which includes newly incorporated carbon equations consistent with those in the Century model. Each run will represent a unique situation defined by state, crop, climate, soil, irrigation type, conservation practice, tillage system, and nutrient management treatment (nutrient rate, application frequency, application timing, and manure category). Results are to be assigned to specific National Resource Inventory points (NRI) to simulate regional and national baselines. In this article we present the modeling approach and discuss the strengths and limitations. Published online  相似文献   

12.
Planning for environmental justice in an urban national park   总被引:1,自引:0,他引:1  
Urban national parks were designed in the 1970s to bring nature and recreational opportunities to socio-economically disadvantaged communities in the USA. Using the theoretical frame of environmental justice, this paper discusses findings of a recent survey of visitors to Los Angeles' Santa Monica Mountains National Recreation Area – the United States' largest urban national park. Findings show park visitors were predominantly white, affluent, and lived nearby. People of colour travelled further, were significantly less likely to be return visitors, and were less inclined to use the park for active recreation. Seemingly, this park fails to meet the needs of the disadvantaged urban communities for whom it was created, a problem that may also affect other parks in the United States and potentially parks in other countries. Park planners and managers can take practical steps to increase accessibility to this park for people of colour and low-income earners, and should monitor other parks for patterns of ethno-racially differentiated access and utilisation.  相似文献   

13.
The evolution of sustainability   总被引:1,自引:0,他引:1  
Six separate but related strains of thought have emerged prominently since 1950 in discussions of such phenomena as the interrelationships among rates of population growth, resource use, and pressure on the environment. They are the ecological/carrying capacity root, the resources/environment root, the biosphere root, the critique of technology root, the no growth/slow growth root, and the ecodevelopment root.Each of these strains of thought was fully developed before the word sustainable itself was used. Many of the roots are based on fundamentally opposing assessments of the future of mankind. Many of the roots, such as the ecology/carrying capacity root, are based on physical concepts, and they exclude normative values. Others, such as the ecodevelopment root, include such values as equity, broad participation in governance, and decentralized government.When the word sustainability was first used in 1972 in the context of man's future, in a British book,Blueprint for Survival, normative concepts were prominent. This continued to be the case when the word was first used in 1974 in the United States to justify a no growth economy.Sustainability was first used in a United Nations document in 1978. Normative concepts, encapsulated in the term ecodevelopment, were prominent in the United Nations publications.After about 1978, the term sustainability began to be used not only in technological articles and reports but also in policy documents culminating in the use of the term in the report of the summit meeting of the Group of Seven in 1989.The roots of the term sustainability are so deeply embedded in fundamentally different concepts, each of which has valid claims to validity, that a search for a single definition seems futile. The existence of multiple meaning is tolerable if each analyst describes clearly what he means by sustainability.  相似文献   

14.
Natural areas of national parks constitute unique ecological and aesthetic resources. Since the inception of national parks, it has been apparent that they are susceptible to threats that result in significant change and damage. Today, major issues concerning management of parks relate to questions of expanded visitor use and what types of facilities are to be deemed appropriate, that is, the dilemma of preservation versus use. In the United States of America, resolution of this dilemma must, strictly speaking, be based upon intent and meaning of Congressional legislation. The traditional interpretation of legislation in the U.S. has been to provide for a balance of use and preservation. However, extensive review of the literature of national park policy reveals a remarkable lack of elaboration and clarification of legislative meaning. Based upon a critical analysis of pertinent legislation, which has heretofore been ignored, we provide an interpretation of legislative meaning which strongly supports a policy of preservation of park resources.  相似文献   

15.
The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a roads environmental impact. Using spatial data for natural and human processes in the Tahoc National Forest (TNF, California, USA), we evaluated the assertion the road has a high potential for impacting the environment. We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer cherry stem roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds.  相似文献   

16.
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park, to help meet the goals of the Natural Resource Challenge—a program to help strengthen natural resource management at national parks. We met this challenge by synthesizing and interpreting natural resource information for planning purposes and we identified information gaps and natural significance of resources. We identified a variety of natural resources at both parks as being globally and/or nationally significant, including large expanses of unfragmented, mixed-mesophytic forests that qualify for wilderness protection, rare plant communities, diverse assemblages of neotropical migratory birds and salamanders, and outstanding aquatic recreational resources. In addition, these parks function, in part, as ecological reserves for plants in and wildlife. With these significant natural resources in mind, we also developed a suite of natural resource management recommendations in light of increasing threats from within and outside park boundaries. We hope that our approach can provide a blueprint for natural resource conservation at publically owned lands.  相似文献   

17.
The United States Consumer Product Safety Commission (CPSC) is concerned that consumer exposure to asbestos from consumer products may present an unreasonable risk of injury. Recently, CPSC has obtained agreement by industry to cease production and distribution of hair dryers containing asbestos heat insulation. CPSC intends to broaden its investigation by selecting consumer products containing asbestos for priority attention. The Commission does not intend to make quantitative estimates of cancer risks posed by exposure to asbestos fibers in making regulatory decisions. This position may lead to a serious waste of resources for the Commission, industry, and society. The Commission should focus its initial attention on those products for which the release of asbestos is significant enough to cause an unreasonable health risk. To make a risk assessment for a particular use of asbestos, CPSC must acquire or request data on asbestos emissions and define unreasonable risk to health.In an attempt to give some meaning to the phrase risk assessment, the primary goal of this paper is to present a detailed risk assessment of exposure to asbestos from hand-held hair dryers. Several scenarios of use are presented using various assumptions regarding time of operation, mixing of fibers in a small room, rate of fiber emission, and time of exposure. The worst case analysis of the health risk of exposure to hair dryer emissions is based on several conservative assumptions and shows that the increased number of deaths per year due to respiratory cancer is 4 for the entire United States population. A more representative case analysis shows the increased number of deaths to be on the order of 0.15 per year.  相似文献   

18.
Regulations at recreation sites have been described as anathema to recreation itself. Many recent authors have suggested that managers use more light-handed techniques, such as information and education, before attempting regulatory and intrusive actions. This study of visitors to Glacier National Park in Montana, USA, during the fall bald eagle migration season demonstrates that, under certain conditions, recreationists will view regulations as a way to enhance the opportunity rather than detract from it. The results reinforce previous suggestions in the literature that managers carefully examine the objectives and consequences of regulations prior to their use.  相似文献   

19.
Current United States National Park Service (NPS) management is challenged to balance visitor use with the environmental and social consequences of automobile use. Wildlife populations in national parks are increasingly vulnerable to road impacts. Other than isolated reports on the incidence of road-related mortality, there is little knowledge of how roads might affect wildlife populations throughout the national park system. Researchers at the Western Transportation Institute synthesized information obtained from a system-wide survey of resource managers to assess the magnitude of their concerns on the impacts of roads on park wildlife. The results characterize current conditions and help identify wildlife-transportation conflicts. A total of 196 national park management units (NPS units) were contacted and 106 responded to our questionnaire. Park resource managers responded that over half of the NPS units’ existing transportation systems were at or above capacity, with traffic volumes currently high or very high in one quarter of them and traffic expected to increase in the majority of units. Data is not generally collected systematically on road-related mortality to wildlife, yet nearly half of the respondents believed road-caused mortality significantly affected wildlife populations. Over one-half believed habitat fragmentation was affecting wildlife populations. Despite these expressed concerns, only 36% of the NPS units used some form of mitigation method to reduce road impacts on wildlife. Nearly half of the respondents expect that these impacts would only worsen in the next five years. Our results underscore the importance for a more systematic approach to address wildlife-roadway conflicts for a situation that is expected to increase in the next five to ten years.  相似文献   

20.
Yosemite National Park is one of the nation's most scenic and ecologically/geologically important parks. Unfortunately, the park is subject to extensive development of concession facilities and associated high levels of visitor use. Those concerned with preservation of the park's resources have attempted to limit the types and extent of such facilities to reduce adverse impacts. Strictly speaking, resolution of the preservation versus use controversy must be based on whether the National Park Service is adhering to its legislative mandate to regulate development and use in the parks. The common interpretation of legislative mandates for national parks, including Yosemite, is that they call for a difficult balancing between the conflicting goals of preservation and use. Accordingly, although concession developments cause significant impacts, they usually have been interpreted to be within the legal discretion allowed the secretary of the interior. However, the usual interpretations of the meanings of legislative mandates for Yosemite National Park have not considered Title 16 United States Code §55, which is a very restrictive statute limiting concession facilities. Many of the limitations imposed on concession facilities by the plain language of the statute have been exceeded. If it can be shown that 16 United States Code §55 is a valid statute, the policy implications for park management in Yosemite National Park would be considerable — namely, that significant reductions in concession facilities could be required. This article examines whether the statute can reasonably be thought to be valid and encourages others to conduct further examination of this question.  相似文献   

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