摘要:

ABSTRACT:This study presents analytic and graphical techniques for estimation and optimization of kinematic wave parameters. Because the techniques are derived from the kinematic wave theory, the optimized parameter values will have minimum bias in them.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01832.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01833.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:In coastal confined aquifers, the extent of the salt‐water wedge due to natural ground‐water flow can be determined by available methods. If water is pumped by a discharge well, the quality of the water depends upon the rate and duration of pumping as well as the location of the well. A study has been made to find the extent of the progress of salt‐water intrusion due to the operation of one discharge well taking into account various conditions of aquifer properties, pump capacities, natural flows, time effects, and well locations. Dimension‐less solutions for specific conditions have been obtained by means of a simple computer program. Range of most common conditions is discussed. One of the main findings of this study was that salt water may be pumped out of a well even if it is located in an initially totally fresh‐water zone beyond the natural salt/fresh‐wate

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01834.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:Concentrations of ammonium‐ and nitrate‐nitrogen of about 10,000 ppm moved from an untreated surface storage pond into the ground water in the sandy beds of the surficial sediments in northeastern North Carolina. This high concentration of nitrogen moved through the permeable sandy beds with the ground water above the Yorktown Formation aquiclude to the Chowan River with only minor dispersion normal to the hydraulic gradient. There was essentially no nitrogen movement into the Yorktown aquiclude even though solutions of 2,000 ppm (sol basis) had been in the overlying sediments for 2 to 3 years The possibility of the nitrogen moving into the deeper quifers used for community water supplies is very small. Only the shallow ground water above the Yorktown Formation in the immediate area will be contaminated with nitrogen because there is little lateral dispersion away from the flow of ground water toward the Chowan Ri

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01835.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:Natural aquatic bacterial populations in three streams located at the Savannah River Project, Aiken, S.C. have been studied in relation to the effects of ambient temperatures, dissolved River Project, Aiken, oxygen (DO), nitrate and phosphate concentrations.3Samples collected at monthly intervals for a period of one year from each system, were plated in duplicate at each of two dilutions on 1/4 strength Standard Plate Count Agar (Difco). After incubation at 25±1 °C for four days, total colony forming units, percent chromagens, and number of colony types (diversity) were determined and colonies were picked for identification.Temperatures were generally equal in two of the streams throughout the year, being lowest in Upper Three Runs (U3R) and Tirns Branch (TB), and highest in the Ash Basin System (ABS). DO content did not vary appreciably between the streams. Nitrates and phosphates were lowest in U3R, next lowest in TB, higher in the last station in ABS, and highest in the ash basin per se. Total colony forming units were highest in the ash basin, whereas chromagen percentage and diversity were highest in the last station in ABS. Results of these studies indicate that high nitrates and phosphates, in the absence of high organic carbon concentrations, have little, if any detrimental effect on the stability of natural aquatic bacterial population

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01836.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:Overwinter draw down can be a useful technique for aquatic plant management. Its effectiveness depends largely on the susceptibility of nuisance species to draw down. A single overwinter draw down provided good control of aquatic plants in a flowage dominated byPotamogeton robbinsiiLittle additional control was gained by a second draw down the following winter. Rapid reinvasion of plants after draw down ceased dictates continued management. To avoid fish kills caused by low dissolved oxygen levels caution is advised when using overwinter draw down. The growth ofZizania aquaticawas not negatively influenced by draw down. The influence on water quality of nutrient release from decaying vegetation and exposed bottom sediments was uncertain.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01837.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:A methodology is developed for examining the environmental and developmental conflicts inherent in the classification process of a wild river. The Salmon River in Idaho is used as an example of the methodology. The steps were: 1. a resource inventory, 2. an evaluation methodology, and 3. an economic comparison of resource use tradeoffs. Alternatives for the Salmon were examined, following generally the procedures outlined in the United States Water Resources Council'sEstablishment of Principles and Standards for Planning Water and Related Land ResourcesFinal comparisons showed that hydroelectric development had greater net benefits than outdoor recreation at up to a three percent recreation growth rate. When recreation use grew at a faster rate, recreation had a considerable margin of net benefits in its favor.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01838.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:In situ and remote sensing techniques for measuring thermal plumes are compared for data taken at the Point Beach Nuclear Power Plant on Lake Michigan for five separate occasions. The in situ method employed a boat whose position was determined with a microwave ranging system. Temperatures at the surface and at various depths were measured with fast response thermistor probes. The remote sensing technique utilized an infrared scanner in the 8 to 14 micron range. Comparison of the plumes indicates good agreement with respect to plume configurations, areas within isotherms and centerline temperature decays for all except one occasion, a calm day characterized by no waves, low wind and ambient current velocities. Robable reasons for disagreement under such ambient conditions are discussed. The inherent advantages and disadvantages of each method are discussed in light of the results of the five sets of data. This includes both the data collecting and data analyzing procedures. It is concluded that judicious combination of both methods offers a better picture of thermal plumes than can be obtained by either technique alone.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01839.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01840.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

ABSTRACT:Two soil water functions, hydraulic conductivity K(θ) and diffusivity D(θ), were estimated by two methods In one method D(θ) was estimated according to Bruce and Klute (1956), and K(θ) was calculated from D(θ) and the retention curve. In the second, K(θ) was obtained by field estimation, with D(θ) being calculated from K(θ) and the retention curve.The criterion of reliability for both methods was agreement between experimental and predicted distribution of soil water content. The prediction was made using the functions K(θ) and D(θ) as soil water parameters in both methods.Theoretical and experimental agreement was generally good. The first method, however, was found to be best for high soil water content and the second for low soil water content. In addition, the water content at the end of the monotonic increase of function D(θ) (estimated according to Bruce and Klute 1956) was found to be about the upper limit of field soil water content. It can be used as a boundary condition in the numerical solution of a cylindrical model of infiltration from a trickle source. It was concluded that the best agreement between theory and experiment can be found when the combined values of D(θ) and K(θ) from both methods of estimat

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1975.tb01841.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY