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981.
Alan Miller 《The Environmentalist》1982,2(3):223-231
Summary This is a paper about problem-solving styles in Environmental Management and the specific deficiencies in these styles that
might be groupd under the label ‘tunnel vision’. The latter, a form of selective attention, contributes to inadequate problem-formulation,
partial solutions to complex problems and to the generation of even more intractable, additional problems. Examples of tunnel
vision in military and environmental decision-making are discussed, together with the situational, personal and educational
factors that exacerbate its influence. The paper concludes with some recommendations for changes in professional education
that might help to recduce the occurrence of tunnel vision.
Dr Alan Miller who is now associate professor at the University of New Brunswick received his training in biology (in England)
and ecology (in Canada). He then spent several years pursuing research at the Northwest Institute for Medical Research in
Chicago, USA. A growing interest in the human aspects of environmental and medical problems led to a further graduate study
in psychology, followed by teaching positions in Ireland and Canada. His current interests include: the education of environmental
professional; the psychosocial problems involved in environmental management, and, the problems inherent in interdisciplinary
project groups. 相似文献
982.
ABSTRACT: Equations were developed to transform peak flows and to adapt design hydrographs and unit hydrographs from gaged watersheds to ungaged watersheds with similar hydrologic characteristics. Dimensional analysis was used to develop adjustment equations for peak flow and time base, and these equations were reinforced with results from regional flood frequency research. The authors believe that the use of these transformation equations should yield more reliable flood peak values and hydrogrphs than the common use of empirical flood estimating curves or equations. 相似文献
983.
Alan R. Hill 《Journal of the American Water Resources Association》1981,17(4):627-634
: The export of dissolved molybdate reactive phosphorus (DMRP) from 22 watersheds in the Duffin Creek drainage basin near Toronto Ontario was measured over a 25-month period. The annual average loss varied from 0.027 to 2.11 kg P/ha. Phosphorus levels in a number of watersheds were strongly influenced by effluent from a sewage treatment plant which contributed about 68 percent of the annual DMRP input to Duffin Creek. An analysis of 12 watersheds which did not contain major point pollution sources revealed that DMRP concentration and losses had a significant positive correlation with crop area and a strong negative association with forest, abandoned farm land, and area of sand + sandy loam soils. The causal relationships underlying these simple correlations are difficult to evaluate because of considerable multicollinearity between land use, soil, and topographic variables. Analysis of a mass balance for the downstream reaches of Duffin Creek indicated that there was considerable retention of phosphorus in the river channel particularly during summer low flows. 相似文献
984.
Ronald A. Chadderton Arthur C. Miller 《Journal of the American Water Resources Association》1980,16(2):235-242
ABSTRACT: Results of studies which have considered the relative merit of various friction slope averaging equations previously used in water surface profile computations are described. Limitations of the most accurate equation known for the M2 profile have indicated that a new equation which gives more emphasis to the upstream energy gradient is desirable. Based upon friction slope curves developed for M2 water surface profiles two new equations, one a parabolic and the other an elliptical approximation, are presented. The behavior of the new equations and of the previously most recommended equation is described by test calculations. The elliptical equation performed more satisfactorily than the harmonic method commonly recommended for M2 profile computations. Insertion of an additional cross-section about 50 feet upstream from a critical depth section was found to reduce computational errors for any energy gradient averaging method. 相似文献
985.
Arthur C. Miller Sonja N. Kerr Donald J. Spaeder 《Journal of the American Water Resources Association》1983,19(4):625-630
ABSTRACT Unit hydrograph theory is one of the most widely used techniques to predict surface runoff. The present study is concerned with the Snyder unit hydrograph and the calibration of the Snyder coefficients for Pennsylvania. Twenty-seven study basins were selected, located randomly across the state. With the rainfall and runoff recorded for several events for each basin (more than 500 events were analyzed) unit hydrographs were calculated and the Snyder coefficients determined. A map of the coefficients was drawn to illustrate the variability in the coefficients and two equations using multiple regression theory were developed. The unexplained variability of the coefficients suggests that upper and lower bounds on the peak flow might be placed on storm hydrographs developed for ungaged watersheds. 相似文献
986.
Jon R. Miller Daniel A. Underwood 《Journal of the American Water Resources Association》1983,19(4):631-640
ABSTRACT Financing and repayment provisions of western water projects effect transfers of income among federal taxpayers, electric power users, local water users, and property owners. We use the Bonneville Unit of the Central Utah Project as a case study in the distribution of municipal and industrial water costs. We examine the distribution of costs among taxpayers and water users in different political/geographical jurisdictions, and how this distribution is affected by water law, cost allocation procedures, and the choice of revenue source for local repayment of reimbursable costs. In light of the magnitude of distributional effects of present water policy, we conclude that lack of open debate on water issues is unfortunate. We conclude with speculation on the relationship of western water policy to the motivation of western water leaders who are instrumental in its formulation 相似文献
987.
Soil is fragile and nonrenewable but the most basic of natural resources. It has a capacity to tolerate continuous use but only with proper management. Improper soil management and indiscriminate use of chemicals have contributed to some severe global environmental issues, e.g., volatilization losses and contamination of natural waters by sediments and agricultural fertilizers and pesticides. The increasing substitution of energy for labor and other cultural inputs in agriculture is another issue. Fertilizers and chemicals account for about 25% of the production energy investment in agriculture. An additional 60% is accounted for by machinery, gasoline, electricity, and power-related inputs. Fertilizer additions to cropland are not utilized fully and significant amounts, depending on conditions, are either lost in surface runoff or leached into the ground water. The annual discharge of dissolved solids from agricultural lands to the waterways in the USA is substantial. The increasing use of herbicides in agriculture is a threat to the quality of surface and ground water, although this threat is dependent upon both the chemistry of the compound and the ecosystem in which it is used. Especially within the Third World, development of an environmental ethic and environmental laws have not kept pace with the increase in pesticide use. Above all is the severe and global problem of soil degradation currently occurring at the rate of five to seven million hectares per year. The policy and moral aspects of these issues are discussed. 相似文献
988.
ABSTRACT: The National Regulatory Research Institute has recommended the merger of small rural water districts in the United States. Success at bringing about merger of these districts, which contain fewer than 3,500 customers, has been highly limited. The subject of this paper is a demonstration project that may act as a catalyst to achieve the desired goal of regionalization. A computerized hydraulic data management program (CHDMP) was developed for a case study in Nelson County, Kentucky. University professors, graduate students, and two water utilities’ staffs cooperated in network analysis employing computer hardware and software. The utilities’ staffs were taught the science and technology of hydraulic model preparation, simulation, and analysis for the case study distribution systems. As an integrated system, the model contained 294 pipes, 234 nodes, six pumps, and 11 tanks. Each utility's problem areas were identified and some of the individual and mutual benefits of hydraulic planning were illustrated. A dialogue resulted between the managers. Each manager described his goals and agreed that, although political merger was not feasible at the present time, future economic factors could be a definite influence in reversing that decision. 相似文献
989.
Horst F. Siewert Carla J. Miller Byron G. Torke 《Journal of the American Water Resources Association》1989,25(3):685-689
ABSTRACT: Water samples and macroinvertebrates were collected from Finley Creek, Indiana, both before and two years after the cleanup of a nearby hazardous waste site. Water quality constituents were compared between years. Below the disposal site higher concentrations of constituents were found before and after the cleanup. However, two years after the cleanup, an improvement of water quality was observed. Total dissolved solids decreased by 52% and macroinvertebrate taxa increased by 44%. 相似文献
990.
The Delphi approach to the mediation of environmental disputes 总被引:1,自引:1,他引:1
Environmental disputes, in many countries, have taken on a ritualistic character. Their persistence, even after prolonged analysis and debate, suggests that they result from ideological rather than factual differences. Since no single ideological position holds a monopoly on the truth, effective environmental management would seem to require an integration of views, the problem being how to achieve this. One approach to this problem is illustrated in this article. Two factions in the spruce budworm dispute in New Brunswick, Canada, were engaged in a mediation exercise using the Delphi method. Details of the design and execution of this form of mediation are provided, together with an evaluation of the Delphi's effectiveness in this context. 相似文献