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801.
M. Bundgaard-Nielsen C. L. Hwang 《Journal of the American Water Resources Association》1975,11(4):805-810
ABSTRACT: The interaction between the level of taxation and the firms accruing choice of treatment technology is discussed. It is shown that there is a risk of overtaxation, that is, simply increasing taxation may fail to improve environmental quality but only increase production costs and thus consumer prices. 相似文献
802.
Shue Tuck Wong 《Journal of the American Water Resources Association》1979,15(2):396-403
ABSTRACT: Human behavior and response towards storm hazard are examined in this study. One-hundred and twenty flood victims in West Vancouver, British Columbia, were administered a sentence completion test to ascertain how these victims behaved and responded to the flash flood of July 12, 1972. The sentence completion test consisted of 11 sentence stems. Seven of these dealt with the respondent's behavior toward the storm experience, and four with the issue of internal vs. external locus of control. Completions of the seven sentence stems at three time situations showed that West Vancouverites expressed the normal reactions of fear and anxiety before the storm; showed negative emotions during the storm; and displayed a feeling of mutual cooperation after the storm. Completions of the remaining four sentence stems revealed that West Vancouverites emphasized the importance of internal factors, viz., autonomy, drive and hard work, in controlling their lives. They recognized God as a benevolent - protective and almighty - powerful figure. Forty percent of the respondents did not believe in luck, while 8 percent regarded it as important in their lives. One might conclude that West Vancouverites could cope with natural hazardous threats better than those who rely on external factors in directing their lives. 相似文献
803.
Noel D. Uri 《Environmental management》1980,4(5):375-380
A myriad of factors, both economic and political, influenced the voting by members of the United States Congress on the 1978 National Energy Act. Determinant factors considered in our analysis included the percentage of residents in the Congressman's district residing in the central city or on farms; the percentage of residents who belong to labor unions; the average level of education of the residents; oil, coal, and natural gas production in the state relative to total domestic production. The results, determined by means of logit analysis, indicate that the impact on low-income energy consumers, the effect on overall employment, the impact on farmers, and the benefits to energy interests, as well as ideology and the subjective perception that the need exists to do something about the energy situation in the United States, were all important explanatory factors.The author is an economist with the United States Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other Department of Energy staff members. 相似文献
804.
ABSTRACT: This paper discusses the consumptive water needs of the various energy conversion processes including oil shale retorting, coal gasification and liquefaction, electric power generation, and slurry pipelines. Projected energy development water needs in the upper Colorado River and Upper Missouri River basins are compared with projected agricultural needs and water available. The comparative cost and values of water to energy and agricultural development are discussed to emphasize this as well as the political and social factors entering into the picture. 相似文献
805.
Donald J. Epp C. Edwin Young 《Journal of the American Water Resources Association》1981,17(2):215-224
ABSTRACT: Varying treatment levels to meet seasonal variation in assimilative capacity of streams can reduce total costs of treatment. A mathematical model of a Pennsylvania stream based on a theoretically sound approximation of the physical relationships underlying the distribution of DO in a river system was used to determine discharge constraints for an economic optimization model which produced estimates of sewage treatment cost savings. Increasing the number of flow periods during the year enhances cost reducing opportunities even when land application processes are considered. Also, the least cost treatment process for year around operation may not be the least costly under multiple flow period management. 相似文献
806.
Guillermo Cabrera Miguel A. Marino 《Journal of the American Water Resources Association》1976,12(2):317-335
ABSTRACT. Transient, two-dimensional solutions are developed which describe the movement and distribution of a conservative substance in a stream-aquifer system. The solutions are obtained by solving sequentially the groundwater flow and mass transport equations. A variational approach in conjunction with the finite element method is used to solve the groundwater flow equation. Galerkin's approach coupled with the finite element method is used to solve the mass transport equation. Linear approximated triangular elements and a centered scheme of numerical integration are employed to calculate the hydraulic head distribution and the concentration of solute in the flow region. The linear approximation used to define the concentration function within each element is not appropriate for cases involving steep concentration gradients. For such cases, higher order approximations are necessary to assure the continuity of gradients across interelemental boundaries. Numerical examples that illustrate the applicability of the model are presented. 相似文献
807.
Krishan P. Singh 《Journal of the American Water Resources Association》1976,12(2):381-392
ABSTRACT. Unit hydrographs derived by using two methods, linear programming and least squares, are compared. Test data comprise rainfall and runoff information from four storms over the North Branch Potomac River near Cumberland, Maryland. The mathematical bases of these methods for unit-hydrograph derivation are explained. The linear programming method minimizes the sum of absolute deviations, and the least squares method minimizes the sum of the squares of deviations. Computer subroutines are readily available for application of these methods. The unit hydrographs derived with the two methods are practically the same for storms 2 and 3, but differ somewhat for storms 1 and 4. However, the reconstituted direct surface runoff hydrographs are similar to those observed with the exception of the hydrograph for storm 4 which had a relatively more non-uniform rainfall excess of a considerably larger duration. 相似文献
808.
Nnamdi Egbuniwe 《Journal of the American Water Resources Association》1976,12(2):393-398
ABSTRACT. The Governments of Nigeria have planned to build 395 dams in the next five years. Such water resources development may increase the incidence of Schistosomiasis, Malaria, Onchocerciasis, and Trypanosomiasis. Adequate measures should be taken to minimize adverse effects of the projects on the public health. 相似文献
809.
D. G. Wallen 《Journal of the American Water Resources Association》1977,13(2):299-308
ABSTRACT: Data from three ice-covered stations in Lake St. Clair were collected to evaluate the effect of ice and related variables on phytoplankton production. Primary production, phytoplankton standing crop, irradiation and temperature were measured from January to April, 1973. Mean production values ranged from 0.74 mgC/m3/h at station 1 near Mitchell Bay to 3.4 mgC/m3/h in waters at stations 2 and 3 below the Thames River mouth. A similar pattern was observed in chlorophyll a concentration, the mean values ranged from 0.63 μg/1 at station 1 to 2.1 and 1.3 μg/1 at stations 2 and 3. Temperature stratification occurred at the three stations. However, the temperatures at station 1 were consistently more than a degree warmer than at the other two stations. Irradiation was low, having a mean value at the sampling depth of .075 ly/min. The data is interpreted to indicate that the ice-bound phytoplankton were adapted to the low irradiation. It is suggested that the variation observed between stations is related to the formation of a plume by the Thames River and differences in nutrient loads carried by the St. Clair and Thames Rivers. 相似文献
810.
F. Dale Parent Stephen B. Lovejoy 《Journal of the American Water Resources Association》1982,18(4):593-597
ABSTRACT: Concern over the pollution of our lakes and streams has become a major issue in the United States. Sedimentation from sigricultural lands has been identified as a significant factor in water pollution. Some citizens suggest that government should force compliance with soil loss standards, while others suggest that we ask farmers to voluntarily comply. Related questions are “DO farmers think government should be involved in controlling erosion and protecting water quality?”“To what extent should government be involved?” What level of government should be involved? Federal? State? Local?“Why should pay for water quality projects?” Farmers from a small watershed in northeastern Indiana were interviewed before and after a major demonstration project. Their responses suggest that farmers feel that individual landowners should be responsible for controlling erosion and agricultural nonpoint source water pollution. However, over 60 percent of the study fanners indicated that the federal government should play an important role, in terms of both technical and financial assistance. 相似文献