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891.
Michael B. Sonnen Bill B. Dendy Kris P. Lindstrom 《Journal of the American Water Resources Association》1981,17(3):394-398
Farmers from four irrigation districts in Texas and California were questioned about water conservation practices they are now using, those they plan to adopt, and potential incentives that government might offer to induce still further water conservation on their part. While responses differed somewhat from place to place and among individual farmers, the general results were: a) farmers reported that “water conservation” is not new to them, it is something they practice regularly; b) recent innovations such as laser controlled land leveling devices have permitted some substantial water use reductions in recent years; and c) even greater incentive mechanisms that government could provide and that farmers would accept as useful incentives, such as long term low interest loans for water saving equipment, would probably not be able to reduce water use in agriculture much further than 15 percent below current levels. It is recommended nonetheless that Federal agencies and local water districts and individuals should nonetheless pursue water conservation training and education programs, demonstrations of conjunctive use and water banking opportunities for water saving, and increased loan programs for installation of water saving equipment. 相似文献
892.
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
893.
Bruce B. Johnson 《Journal of the American Water Resources Association》1981,17(1):129-132
ABSTRACT: The accounting and repayment practices employed by the Water and Power Resources Service (WPRS) greatly distort the actual resource allocation process and the ultimate repayment to the Federal Treasury. Through a series of transfers of capital repayment obligations to future development with modest or no interest charges, the repayment is reduced to only a fraction of the amount implied. In the case of the Pick-Sloan Missouri Basin Program, the public subsidy of hydroelectric power is estimated to be $2 for every $1 of repayment. For irrigation investment, the direct repayment to the Federal Treasury is less than 10 percent of the annualized cost of the public investment, with irrigators repaying at a rate of less than $0.03 for every dollar of public expenditure. 相似文献
894.
Evelyn B. Haines 《Journal of the American Water Resources Association》1976,12(6):1223-1232
ABSTRACT: Since nitrogen is a nutrient frequently in short supply in coastal ecosystems, an estimate of the nitrogen input via rain was made for the Georgia coast. Water samples collected in 34 separate storms during a 12 month period were analysed for concentrations of ammonia, nitrate plus nitrite, and dissolved organic nitrogen (DON). The range and average concentration in micromoles of nitrogen per liter was 0.0 to 137 (6.3) for ammonia, 1.0 to 21 (7.9) for nitrate plus nitrite, and 0.0 to 13.6 (4.0) for DON. DON, not usually measured in rain, comprised up to 62% of the total nitrogen content. The annual amount of nitrogen contributed by rain to the coast was about 0.3 g N/m2. This value is a small fraction of the calculated nitrogen requirements of coastal plants. More than half the rain samples had pH values less than the CO2 equilibrium pH of 5.6. Values as low as 4.2 were in the range of pH values reported for acid rain in Europe and the northeastern U.S. Total titratable acidity was measured for 12 summer rainwater samples. The results fox 7 individual storms showed a highly linear relation between hydrogen ion concentration and total acidity. However, the elope of the regression line indicated that increases in acidity were not a result of addition of strong acid alone. 相似文献
895.
J. L. Hanisch B. R. Hart W. S. Turetsky H. T. Garabedian G. H. Pain 《Environmental management》1978,2(2):127-133
The body of information presented in this paper is directed to air pollution engineers who are concerned with the effect of indirect sources on ambient concentrations of carbon monoxide (CO). Data taken under controlled conditions are used to empirically derive and calibrate a model for predicting CO concentrations in the vicinity of roadway intersections and other points of possible vehicular congestion. Since the predicted free flow CO contribution of vehicles traveling at normal road speeds is relatively low, it is concluded that idling vehicles at points of congestion are the major cause of CO violations, and that state and federal programs should place more emphasis on relieving congestion and reducing idling emission rates in new vehicles. 相似文献
896.
The information presented in this paper is directed to air pollution engineers who are concerned with monitoring Carbon Monoxide. This paper evaluates systems for CO sampling under conditions where the receptor is located at intersections within 40 meters of the road edge. Non-Dispersive Infrared and electrochemical analysis techniques are used in conjunction with continuous recording, continuous bag sampling, and meter readings at 5 second intervals. The relative accuracy of each system is examined and the conditions for which each system is best suited are described. 相似文献
897.
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
898.
George B. Heaslip 《Environmental management》1977,1(1):15-29
Thousands of individuals throughout the world are now users of satellite data. Hundreds of satellites have been launched—military, navigation, communications, educational, weather, and earth resources. One of the weather satellites (the SMS/GOES) and the NASA earth resources mapping satellite (Landsat) are the subjects of this article. Data from these systems have been highly cost beneficial, not only in the United States, but in developed and developing nations all over the globe as well. There is an increasing demand both for data and for training in data use.Data samples are shown and applications are discussed. Strong reference is made to the value of the digital computer in natural and man-made features mapping and monitoring. Procedures for acquiring NASA data are explained so that the reader may order data for his home region, or for other regions throughout the world which are of interest for their agriculture, forestry, hydrology, marine resources, geology, or land use. The cost of data is incredibly low; some products cost as little as three dollars.Also discussed are the remotely based data-collection platforms that acquire ground or water data daily and relay results to the NASA Landsat or to the NOAA SMS/GOES. 相似文献
899.
W. G. B. Phillips 《Resources Policy》1977,3(4):268-280
The concentration of minerals in the crust forms a continuous distribution between the higher grade reserves mined as ore and the low-grade background mineralization of waste rock. A lognormal distribution could be generated by a mineralization process compatible with the theory of plate tectonics. A computer model of this process is demonstrated. The discussion is extended to other base metals and in particular to the distribution of reduced carbon. Neither base metals nor fossil fuels are ever likely to be exhausted, but they may rise in cost and be superseded by cheaper substitutes. 相似文献
900.
J. B. Murphey D. E. Wallace L. J. Lane 《Journal of the American Water Resources Association》1977,13(1):25-37
ABSTRACT: Critical design characteristics of ephermal runoff such as hydrograph rise time, duration, mean peak discharge, volume, peak-volume ratio, and maximum flood were related to physical basin parameters such as area, shape, slope, drainage density, basin relief, stream length, and combinations of these in intermontane watersheds representative of the Mexican Highland section of the Basin and Range Province. Parameters used were restricted to those easily obtainable from maps or aerial photographs. A parameter expressing basin shape and size was developed which proved to be as accurate a predictor as others used in existing prediction equations tested and was simpler and faster to derive. Simple prediction equations derived for hydrograph characteristics were all significant except for volume at the 5% level; three were significant at the 1% level. Relationships determined are applicable in semi-arid basins of the Southwest up to 60 square miles (155 km2) in area. 相似文献