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141.
R. J. Brozka G. L. Rolfe L. E. Arnold 《Journal of the American Water Resources Association》1981,17(3):443-447
Two intermittent streams on oak-hickory watersheds in southern Illinois were gaged with a V-notched weir and sampled with an automatic water sampler. For three years data were collected on flow volume and water quality. Flow volumes show large variations between years and watersheds. Samples were analyzed for Na+, K+, Ca++, Mg++, P, and NO-3. Water quality was consistently high, although there were significant differences between watersheds. A baseline for water quality has been established for comparison after one of the watersheds is clearcut at a later date. 相似文献
142.
C. T. K. Ching 《Journal of the American Water Resources Association》1981,17(3):454-457
A significant research problem is the assessment of impacts associated with growth and/or decline in a regional economy. A relevant method for analyzing such problems is the Leontief input/output model. Associated with these models are economic multipliers measuring total changes in sales, income, and employment. In this paper, the author contends resource multipliers are equally relevant. The specific form of these multipliers are defined. Water multipliers for a two-county region in central Nevada are presented and their uses described. 相似文献
143.
David R. Hargis Charles A. McCauley 《Journal of the American Water Resources Association》1981,17(3):494-497
Two wellfields have been developed to provide water for a coal fired electric generating station in Arizona. Wellfield No. 1 penetrates the unconfined Coconino Sandstone aquifer, and wellfield No. 2 penetrates the composite Kaibab Limestone-Coconino Sandstone aquifer where ground water occurs under confined conditions. A well in each wellfield was pumped and water level drawdown data were collected before and after acidizing. The drawdown data at the various pumping rates were analyzed to determine the potential benefits of acidizing production water wells in both wellfields. After acidizing, the specific capacity of the well in wellfield No. 1 was improved about 50 percent at water production rates ranging from about 200 to 500 gallons per minute (gpm) (13 to 32 liters per second (lps)). After acidizing, the specific capacity of the well completed in wellfield No. 2 was improved about 100 percent at pumping rates ranging from about 1,250 to 2,200 gpm (79 to 139 lps). An annual saving of approximately 11 percent in pumping costs can be realized in wellfield No. 2, and savings are approximately four percent in wellfield No. 1. Acidization is beneficial for wells that can produce more than 500 gpm (32 lps), and is of marginal value for those that produce less than that amount. 相似文献
144.
S. Lawrence Dingman 《Journal of the American Water Resources Association》1981,17(4):684-690
: In general, the choice among reservoirs for water supply or flow augmentation is a multiobjective problem. Choices are based in part on the yield available from water supply reservoirs or, in the case of flow augmentation reservoirs, on the increase in low flows at downstream locations. Detailed estimates of these effects may be too costly for basin planning purposes. Thus this paper presents methods for rapid estimation of those quantities for New Hampshire. For water supply reservoirs, a composite empirical relation between Y95 (the draft available 95 percent of the time) and storage ratio, S*, is developed from previous studies in the region. For flow augmentation reservoirs, empirical relations between S* and degree of regulation, R*, are applied to each upstream regulating reservoir. Values of regulation arc then summed and divided by the mean flow at the downstream reach of interest. This parameter, (ΓR)*, is then related to increase in flow available 95 percent of the time by an empirical relation. 相似文献
145.
William B. Lord 《Journal of the American Water Resources Association》1981,17(6):1060-1065
ABSTRACT: The Water Resources Council's Principles and Standards stipulate that plans should be formulated to meet national, regional, state, and local needs or problems. It is not clear, however, how appropriate consideration can be given to both national objectives (NED and EQ) and local needs and problems. Two methods of incorporating national objectives and local problem solving into water resources planning are examined. They are plan formulation primarily in pursuit of national objectives, and plan formulation to solve local problems, but constrained by national objectives. The first of these methods is the approach which is becoming increasingly explicit in the development and elaboration of the Water Resources Council's Principles and Standards. The analysis indicates that the Water Resources Council's approach is neither the most practical nor the most desirable of the two methods examined. It creates unnecessary difficulties and fails to achieve its purpose. Plan formulation to solve local problems, but constrained by national objectives not only describes what field planners actually do, but is also more practial and more desirable. 相似文献
146.
E. Earl Whitlatch Peggy L. Asplund 《Journal of the American Water Resources Association》1981,17(2):310-314
ABSTRACT: The cost of water service to rural residents is very high compared to urban areas. This is true even after subsidization by Farmers Home Administration (FmHA) loans and grants. Capital cost data on 44 projects financed by the Ohio office of the FmHA during the period August 1968 to January 1977 are used to derive cost equations for 26 components of rural water distribution systems. These components represent 92 percent of the capital cost of the pipeline distribution systems studied. The data can be used to economically design rural water supply systems from a capital cost viewpoint. More data are needed on operation and maintenance costs as well as central and cluster well costs before totally economic system designs can be undertaken. 相似文献
147.
Application of the Braun-Blanquet cover-abundance scale for vegetation analysis in land development studies 总被引:1,自引:0,他引:1
To document environmental impact predictions for land development, as required by United States government regulatory agencies, vegetation studies are conducted using a variety of methods. Density measurement (stem counts) is one method that is frequently used. However, density measurement of shrub and herbaceous vegetation is time-consuming and costly. As an alternative, the Braun-Blanquet cover-abundance scale was used to analyze vegetation in several ecological studies. Results from one of these studies show that the Braun-Blanquet method requires only one third to one fifth the field time required for the density method. Furthermore, cover-abundance ratings are better suited than density values to elucidate graphically species-environment relationships. For extensive surveys this method provides sufficiently accurate baseline data to allow environmental impact assessment as required by regulatory agencies. 相似文献
148.
D. T. O'Laoghaire 《Journal of the American Water Resources Association》1978,14(4):809-826
ABSTRACT: This paper describes a mathematical model, an algorithm and a computer program that were specially developed to study the problem of a water quality management system undergoing a rapidly increasing environmental stress. The model output will determine the locations, sizes and the timing of construction of new treatment plants plus an overall treatment plant operating policy so that environmental standards are maintained at a minimum cost. The model, as formulated, is a 0-1 mixed integer programming problem which is solved by decomposing it into a capital budgeting problem (solved by Little's branch and bound algorithm) and an operational policy problem (solved by linear programming). The coded algorithm (in FORTRAN 10) has been tested with a semi-realistic example. 相似文献
149.
Paul C. Huszar Melvin B. Sabey 《Journal of the American Water Resources Association》1978,14(4):978-987
ABSTRACT: Current policies for correcting the problem of irrigation return flow pollution tend to attack the symptoms of the problem, rather than its cause. The present institutional arrangement for allocating irrigation water is seen as the source of the problem. This paper examines the water quality benefits of altering the institutional arrangement to allow for irrigation water transfers through a rental market. It is conceptualized that by creating a water rental market an opportunity cost would be associated with the use of irrigation water such that profit maximizing farmers would be induced to use his water supply more efficiently and rent the surplus to other irrigators, thus reducing return flow pollution. It is shown that a water rental market could increase water quality in the Yakima River in southcentral Washington by 31 percent as well as increase farm incomes and crop production. 相似文献
150.
Roger H. Willsie Harry L. Ratt 《Journal of the American Water Resources Association》1974,10(2):360-371
ABSTRACT: The paper outlines both the methods used and the results obtained in a study of the demand for municipal and industrial water for the Seattle region. The study was made as part of a regional water management study program, one objective of which is to “… identify, quantify, and set priorities for all current and future water uses …”. A basic concept in the study of municipal and industrial water use is that the demand for water is derived from the demand for output and the direct services that water provides. Principal characteristics of the study are: (1) Water use is studied by type - residential, commercial, industrial and public -with identification of factors affecting each; (2) Water demands are studied by season as well as on an annual basis; (3) Projections of future water use are tied directly to projections of economic change in the service area; and (4) The effects of alternative policies on water use are estimated. Water use levels are projected under alternative regional growth assumptions provided by the Puget Sound Governmental Conference, a regional planning agency. Thus, the water use planning is consistent with other regional planning programs in this respect. The results can be varied according to changes in specific factors affecting water use. The factors considered in the present study include: single-family residential lot size, distribution of population between single- and multi-family units, per capita water use by multi-family unit residents, and industrial and commercial water use per employee. An income elasticity of demand was estimated for single-family residential water use. 相似文献