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31.
As part of the planning process, maps of natural factors are often superimposed in order to identify areas which are suitable or unsuitable for a particular type of resource management. Overlay maps may also be used to identify analysis areas for predictive modeling of resource productivity and ecological response to management. Current interest in applying computer-assisted mapping technology to making overlay maps is drawing attention to geographic information systems for this purpose. The resultant maps, however, may be so inaccurate or unable to capture significant units of productivity and ecological response that they could lead to imperfect or false conclusions. Recommendations are made on how to proceed in light of these problems.  相似文献   
32.
The Supreme Court's interpretation of the commerce clause controls the balance of power between state and federal governments in the United States. An understanding of the relationship between the different government levels is essential for resource managers concerned with resource and environmental issues. This study examines selected Supreme Court decisions between 1976 and 1988 to answer three questions raised by the commerce clause: (1) Is the regulated item an article of commerce? (2) Do state laws burden interstate commerce? (3) Is federal commerce regulation limited? The balance of power among the justices and the commerce clause theories affecting the federal role in resource management are also examined. Since ratification of the Constitution, the Supreme Court has continuously increased federal power, but states have power to act independently as long as contradictory federal laws do not exist and state law does not impermissively affect commerce. If Congress regulates an individual's use of resources, their power is unquestioned. Future Court decisions will not significantly reduce the federal role in resource management even if the Court's membership changes. Even the supporters of states' rights on the Court realize increased federal power is a necessary part of the country's evolution. The purpose of the commerce clause is to create a national economic unit with free location principles. The Court supports this purpose today and will in the future.  相似文献   
33.
The National Forest Management Act (1976) specifies that multiresource inventories be conducted to provide baseline data for development and, later, monitoring of national forest management plans. This mandate entails the most ambitious and complex resource planning effort ever attempted. In this paper we evaluate the structure and use of current inventory-monitoring programs and recommend a framework for gathering data to improve national forest planning. Current national guidelines are general and provide only basic directions to forest-level planners. Forest inventories have traditionally concentrated on timber. Although these inventories are often well designed, the questions we are now asking about forest resources have outgrown these methods. Forest management is impeded by general confusion over definitions of resources and the interactions among them. We outline a simple classification scheme that centers on identification of basic ecosystem elements that can be readily measured. Furthermore, spatial and temporal scales must be considered in the design of inventory-monitoring programs. The concept of ecological indicators is reviewed, and caution is advised in their use. Inventory-monitoring programs should be goal-directed and based on as rigorous a statistical design as possible. We also review fundamental issues of variable selection, validation, and sampling bias. We conclude by developing a flexible inventory-monitoring program that is designed to provide information on individual characteristics of the environment, rather than being based on fixed definitions of resources.  相似文献   
34.
A resource survey and planning method for parks, reserves, and other environmentally significant areas (ESAs) is presented in the context of a holistic balanced approach to land use and environmental management. This method provides a framework for the acquisition, analysis, presentation, and application of diverse ecological data pertinent to land use planning and resource management within ESAs. Through the independent analysis and subsequent integration of abiotic, biotic, and cultural or ABC information, land areas within an ESA are identified in terms of their relative environmental significance and environmental constraints. The former term encompasses wildlife, historic, and other resource values, while the latter term reflects biophysical hazards and sensitivities, and land use conflicts. The method thus calls for a matching of an ESA's distinctive attributes with appropriate land use and institutional arrancements through an analysis of available acts, regulations, agencies, and other conservation and land use management mechanisms. The method culminates with a management proposal showing proposed park or reserve allocations, buffer areas, or other land use controls aimed at preserving an ESA's special ecological qualities, while providing for resource development. The authors suggest that all resource management decisions affecting ESA's should be governed by a philosophical stance that recognizes a spectrum of broad land use types, ranging from preservation to extractive use and rehabilitation.  相似文献   
35.
Issues of resource conservation and development are essentially about choice between alternative uses of land. Resource evaluation in rural planning has usually been based on assessments of land quality or capability in relation to a variety of alternative uses. In the case of wildlife, choices have to be made as to whether the wildlife resource is worth conserving at all and if so, which sites should be used. Considerable efforts have been made to rationalise, improve and make explicit the way in which choices are made, and this paper reviews the current position and draws attention to issues and developments which could lead to improvements in current practice.  相似文献   
36.
The commercial fishing fleet in New Bedford, Massachusetts, USA, harvests seafood on George’s Bank, home of one of the nation’s most productive fisheries. We calculated the energy return on investment (EROI) and carbon intensity of protein harvest in the New Bedford fisheries from 1968 to 1988. EROI is the ratio of the energy content of the edible fish protein harvested to the quantity of fossil fuel energy used directly in the harvesting process. Carbon intensity is the quantity of carbon dioxide (CO2) released (from the burning of fossil fuels) per calorie of edible fish protein harvested. The results show that the EROI of protein harvest declined from 0.18 to 0.028 from 1968 to 1988, indicating that the energy used to harvest seafood increased from about 6 to 36 kcal of fuel for each kilocalorie of protein harvested. The quantity of CO2 released per calorie of edible fish protein is a linear function of energy use and therefore increased in a similar manner. During this period there was a large increase in fishing effort (caused by the increase in the real price of seafood products, favorable tax treatment for new vessel construction, and low interest loans from the government), and a decline in several important species of fish. The results suggest that fishing pressure could be managed effectively by the regulation of fuel use by the fleet. Despite the increase in the price of many seafood products, fishermen absorbed many of the costs of increasing scarcity in the form of longer working hours and fewer men per vessel.  相似文献   
37.
The Platte River Basin consists of tributaries largely in Wyoming, Colorado and Western Nebraska, with the main stem in Central Nebraska. Critical wildlife habitat on the main stem requires additional in-stream flows. The watershed is one hosting multiple resources, a variety of users, and managed by an array of state and federal agencies. This study proposes a basis for securing in-stream flows for the Platte River. Candidate water supply mechanisms are suggested based on the way in which Casper, Wyoming secured water for its municipal needs. Canal lining is compared to a dam project, increasing reservoir storage, and purchasing water rights, with consideration also made for water pricing to reduce municipal use. Comparisons are based on economic efficiency, potential water conservation, and property rights criteria. Canal lining, coupled with demand management, is shown to conserve water best, given the set of efficiency and cost criteria for in-stream flow enhancement. The approach offers an opportunity to organize the water supply choice context in a transboundary watershed when quantitative information is limited.  相似文献   
38.
This article reviews recent progress in material flow analysis and its use in providing resource productivity indicators and is based on developments in Japanese policy toward a sound material-cycle society and in international forums such as within the Organisation for Economic Development and Cooperation, covering both institutional and methodological issues. Indicators derived from economy-wide material flow accounts such as direct material inputs are useful to demonstrate the absolute size of a physical economy and to reinforce the need to both reduce consumption of natural resources and limit waste generation. Interpretation of material flows as resources and potential environmental impacts is discussed, and linkages between the size of material flows and specific environmental impacts and damage must be further elaborated for use in environmental policy. Lessons learned from the practical use of resource productivity indicators are also discussed. Additional indicators are needed that can be used to evaluate the performance of microeconomic contributors. The need for an integrated approach that links upstream resource issues and downstream waste issues through the 3Rs concept or the circular economy/society concept is attracting increasing attention. Consequently, the accumulation of reliable scientific knowledge and data in this field in a fully international context is essential.  相似文献   
39.
Since the presentation of the Leopold Report (Leopold et al. 1963) to the United States Secretary of the Interior, recommendations in the document for managing natural park resources on the ecosystem level have been included in the management policies of the National Park Service. In many instances, however, management programs have continued to focus on individual resource problems, without apparent concern for the ecological consequences on ecosystems. Without knowledge of the interrelationships of ecosystem components, solving one problem may result in other resource problems. Graphic approaches are presented as potential tools to view these complex interrelationships relative to the needs of the resource manager. Interpreting the dynamics of aquatic systems is emphasized.  相似文献   
40.
This paper contributes to on-going attempts at bringing together two influential ideas in water governance: Integrated Water Resource Management (IWRM) and adaptive governance. In particular, a tension remains between the call in IWRM for the use of formal institutions, such as river basin organisations, to secure public policy integration, and the assumptions in adaptive governance in favour of informal collaboration between essentially independent policy actors. To clarify this relationship, this article draws on theoretical research on public policy integration, and uses these insights in an empirical setting to identify mechanisms that can facilitate effective policy integration for adaptive water governance. The research is based on recent attempts in Scotland to implement IWRM ideas to improve flood management. Several governance mechanisms were adopted to facilitate the integration of flood, water and rural land use policies. Six Scottish policy regimes are analysed using documentary sources and interviews. Results challenge the idea that collaboration should primarily be built on either river basin organisations or informal mechanisms. We identify a mix of informal and statutory-based mechanisms which may secure political and technocratic commitment to policy integration.  相似文献   
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