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951.
This article analyzes water quality on a global scale. An overview of the global water supply and demand situation is presented first, including regional and country information, as well as data on selected water use patterns. The focus then shifts to a discussion of water pollution, its various causes, impact, and remedies, with emphasis on legal and administrative solutions. Water pollution control expenditures and the resultant achievements are dealt with in the final third of the article, with projections to 1995. A wide variety of published sources was dovetailed to obtain a composite picture and most likely scenario; this was supplemented with primary interviews by the author conducted in North America, Western and Eastern Europe, and Oceania at the start of the 1980s.  相似文献   
952.
Fishermen were aggregated into high-, mid-, and low-consumptive groups according to the importance they placed on catching fish. Analysis of variance indicated that each consumptive group was unique in the importance it placed on other fish-related variables. Low-consumptive fishermen rated most other aspects of the fishing experience, such as interacting with nature, relaxation, and escaping the daily routine, more important than did high-consumptive fishermen. Low-consumptive fishermen also fished more frequently and were generally more satisfied with their most recent fishing trip than were high-consumptive-oriented fishermen. The three groups can be viewed as different fishing constituencies. By understanding their characteristics, we can gain additional insights into the impacts of management decisions on recreational fishermen and their experiences.  相似文献   
953.
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   
954.
The historical and regional context to the development of a planning strategy for Barcelona is examined, providing an explanation of the obstacles to development of new towns in the region, and that of Riera de Caldes in particular. The paper analyses the reasons for the failure to develop the new town, and its subsequent reversion to rural uses and a place of pilgrimage for environmentalists.  相似文献   
955.
The computer and telecommunications technology has created new opportunities for developing interaction between offices and enterprises located far away from each other. Even if the market forces favour concentration to R & D centres in the big cities and in university towns, there are expectations that the distance over‐bridging qualities of the new technology can create development opportunities for sparsely populated peripheral areas. In this paper the interplay between the new technology and other important factors in the local and regional environment are discussed with the focus on both opportunities and restrictions.  相似文献   
956.
ABSTRACT: Water resource scientists face complex tasks in evaluating aspects of water projects, but relatively few assessment procedures have been applied and accepted as standard applications. Decision-makers often rely on environmental assessments to evaluate the value and operation of projects. There is often confusion about scientists' role in policy decisions. The scientist can affect policy-making as an expert withess, an advocate or a surrogate. By understanding the policy process, scientists can make their work more “policy relevant.” Using the Terror Lake hydro project in Alaska as a guide, three lessons are discussed: (1) not all problems are able to be solved with technology; (2) policy-relevant technology is rarely imposed on a problem; and (3) the scientist need not just react to the policy process, but can have an impact on how that process unfolds.  相似文献   
957.
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   
958.
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   
959.
ABSTRACT: The impacts of alternative forest watershed management practices are examined from a multicriterion viewpoint in order to select the most satisfactory management scheme. The selection process is carried out using two types of multicriterion decision making techniques: the outranking types of ELECTRE I and II, and the distance-based type of compromise programming (CP). The process is illustrated using the U.S. Forest Service Beaver Creek Experimental Watershed in the Salt-Verde River Basin of Arizona as an example. The desired objectives of the experimental study and the alternative forest watershed resources management schemes are transformed into an evaluation matrix of alternatives versus criteria array. Analyses of the matrix using the aforementioned techniques result in a complete preference ordering of the feasible alternatives in the cases of ELECTRE LI and CP and a partial ordering when ELECTRE I is used. In addition, some sensitivity analyses have been performed and showed ELECTRE II and CP to be fairly robust with respect to parameter changes, while ELECTRE I being highly sensitive to changes in threshold levels. Overall the three techniques pointed out that 65 percent vegetation cut is the best management scheme, while the next best is shown to be 50 percent vegetation cut.  相似文献   
960.
ABSTRACT: Texas is one of the states in which limitations in water supplies could severely constrain economic growth in certain areas. The traditional planning approach for addressing this problem has involved devising schemes for large water development projects, which for many years included the importation of water from other states. Now the attitude towards water resource management is changing, and it is generally agreed that better management of existing supplies is the preferred approach. In this paper we review some of the changes that have recently occurred in Texas, including attempts to streamline the water institutions in such a way that they might be more responsive to the need for more comprehensive management of water resources statewide, with greater emphasis on social and environmental concerns.  相似文献   
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