摘要:

Conventionally hydrologists have used regression analysis for solving their multivariate problems. Recently other multivariate statistical methods have been advocated. This paper discusses and compares the effectiveness of six methods of analysis: regression, principal component, varimax, oblimax, key cluster, and object. Strengths and weaknesses of each method are discussed, and the combination of principal component regression with varimax rotation of the factor weight matrix is recommended for an initial analysis of multifactor hydrologic problems.

ISSN:0043-1397    

DOI:10.1029/WR001i004p00447

年代:1965

数据来源: WILEY

摘要:

The conjunctive use of nonlinear integer programming and principal component analysis is suggested for specification of a constrained optimal gaging program whose objective is to define efficient estimates of the several annual means. The assumptions in the analysis are restrictive; data from thensites are presumed to be available forn1years, andn2years of additional gaging are contemplated. The observations are presumed to derive from a multivariate normal population with no serial correlation. The method specifies which sites from among thencandidates should be continued and which should be estimated by linear regression. Although the discussion is directed toward hydrologie applications, it should be recognized that the technique is generally applicable to sampling surveys.

ISSN:0043-1397    

DOI:10.1029/WR001i004p00463

年代:1965

数据来源: WILEY

摘要:

The accuracy and precision of two field methods and a laboratory method for determining detergent (alkylbenzenesulfonate) in water have been investigated. Commercially available kits were used for the field methods. A total of 660 determinations were made by two analysts on prepared solutions containing both branched‐chain and straight‐chain detergents. One of the field methods contains large amounts of negative bias that vary with concentration level. The other field method has poorer precision than the laboratory method but no large amount of b

ISSN:0043-1397    

DOI:10.1029/WR001i004p00471

年代:1965

数据来源: WILEY

摘要:

Recent years have seen a marked increase in the rate of investment in facilities for water quality control and a concurrent recognition of the need to program water resource use on a regional basis. This paper outlines the nature of regional water quality systems and presents programming models for several water quality improvement problems. A linear programming formulation of a static improvement in quality is contrasted with a traditional policy for programming improvements; the traditional policy results in a mixed integer problem. The maximization of the ratio of benefits to costs of an improvement program is transformed to a linear programming problem. A stochastic natural environment leads to other programming models. A discussion of the application of least‐cost models terminates the pape

ISSN:0043-1397    

DOI:10.1029/WR001i004p00477

年代:1965

数据来源: WILEY

摘要:

A study was made of the possibility of representing the hourly rainfall process observed at a point by a simple model using a digital computer. The purpose of the modeling procedure is to produce synthetic hourly rainfall data for the Stanford watershed model to make possible long records of synthetic streamflows. The model represents the hourly rainfall process by a sixth‐order Markov chain and is shown to be a suitable procedure. Dry periods between storms are found to be longer than dry periods that occur in nature. When used in the Stanford watershed model, the synthetic data produce hydrologic characteristics for a test watershed that are in good agreement with those derived from historic dat

ISSN:0043-1397    

DOI:10.1029/WR001i004p00489

年代:1965

数据来源: WILEY

摘要:

The conceptual model upon which studies of hydrologic relations between unit‐source and complex watersheds are based is discussed. Comparisons of measured storm runoff from two complex watersheds with that predicted by combining storm runoff of representative unit‐source watersheds in accordance with the conceptual model revealed that the measured values were different from those predicted. Within the framework of the present model, unit‐source watersheds cannot be used to predict the effects of land use changes on complex watersheds. If the unit‐source concept is to find effective application, an improved model must be developed. Three phenomena that seem necessary in a more realistic model are discussed: (1) Interflow, (2) partial area runoff production, and (3) the influence upon downslope runoff production of runoff from upper

ISSN:0043-1397    

DOI:10.1029/WR001i004p00499

年代:1965

数据来源: WILEY

摘要:

Large‐scale areal variations in low‐flow characteristics of streamflow are caused primarily by differences in geology in the 576‐square‐mile Swatara Creek basin just east of Harrisburg, Pennsylvania. Although the low‐flow index (the average annual minimum daily flow) of small streams in the basin ranges from 0 to slightly more than 1.0 cubic foot per second per square mile (csm), the flows within each geologic zone show marked similarity, except where affected by mining, diversion, or other activity of man. These natural average minimum flows are lowest in the area underlain by the Martinsburg Shale and range from 0.01 to 0.10 csm. Moderate average minimum flows of 0.1 to 0.2 csm occur in the areas underlain by sandstone, conglomerate, and shale in the northern mountainous part of the basin; greater average minimum flows of 0.3 to 0.4 csm occur in the zone in the southern part of the basin underlain by the Gettysburg Shale, which consists mostly of coarse‐grained sandstone. The variability in the low‐flow indices of streams is greatest in the area underlain by various limestones and dolomites, ranging from zero to over 1.0 csm. However, even within this zone of limestones and dolomites there is reasonable consistency to the low flows within each of the sever

ISSN:0043-1397    

DOI:10.1029/WR001i004p00509

年代:1965

数据来源: WILEY

摘要:

Recession flows from eight small watersheds in central Arizona are described and differentiated on the basis of watershed precipitation and vegetative cover. Average or ‘master’ curves were prepared for each watershed and described in terms of standard deviation and coefficient of variation of the slopes. Duration of master recessions, which varied from 1 to 23 hours, depended on season and vegetation type. Maximum peak discharges, which varied from 30 to 125 csm, usually came from summer rainstorms. The steepest master recession slope was 1.6 on an upper woodland watershed for summer storms; the most gradual was 0.1 for a pine forest watershed for winter‐spring s

ISSN:0043-1397    

DOI:10.1029/WR001i004p00517

年代:1965

数据来源: WILEY

摘要:

Schmid and Luthin have proposed a mathematical solution for draining sloping land by evenly spaced ditches that reach to the impermeable layer. Their theory was based on solutions of the Boussinesq equation for the water table in equilibrium with rainfall. The Dupuit‐Forchheimer assumptions inherent in the Boussinesq equation lead to an undetermined error in the results. A Hele‐Shaw model used to solve the same problem indicated that the error due to the Dupuit‐Forchheimer assumption was small for slopes less than 30%. For slopes greater than 30% the mathematical solution gave ditch spacings that were too

ISSN:0043-1397    

DOI:10.1029/WR001i004p00523

年代:1965

数据来源: WILEY

摘要:

A four‐year study of drainage effluent obtained from 15 tile drainage systems located in the arid San Joaquin Valley of California showed that the concentration of salts and the various ions discharged in the tile effluent decreased, logarithmically, from the time that the tile systems were installed. Regression equations and correlation coefficients are presented for total salts, boron, sodium, calcium plus magnesium, chloride and sulfate ions, versus time from 0 to 12 years of tile drainage system age. The relationships presented could change with more intensive drainage and more liberal use of irrigation water, providing a more rapid trend toward equilibriu

ISSN:0043-1397    

DOI:10.1029/WR001i004p00531

年代:1965

数据来源: WILEY