摘要:

ABSTRACT:The Woodlands, a totally planned community north of Houston, Texas, was studied in detail in an effort to develop a master drainage plan which minimizes adverse impact on the 100‐year floodplain. A total of 40 HEC‐1 and HEC‐2 computer runs were made to evaluate various development, channelization, and reservoir storage op

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05369.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:Economic models sometimes indicate that irrigation water is misallocated in agriculture, especially when it appears that the marginal value product is higher in other uses (such as for hydro‐power). Historically, trends tend to contradict this reasoning, however, especially since irrigation has grown from 20 million acres in 1940 to over 50 million acres in 1980. Results of this study tend to indicate that as agriculture becomes more and more intensive (in terms of inputs), irrigation is part of that long term trend. Further, major economic variables, such as output and investments in agriculture, appear to be more highly correlated with irrigated land than with dryland agriculture. Recent data indicate an upper limit of about 320 million acres for dryland farming in the United States, while no such constraint is apparent for irrigated agricultur

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05370.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:An input‐output model was developed to predict changes in Salton Sea salinity and water level until the year 2000 due to proposed water conservation efforts and geothermal and solar pond energy developments. The model SALINP provided good agreement with the observed salinities for 1960–80. While SALINP was not overly sensitive to one‐year changes in any of the major inputs, a change in the historical means of the Imperial Valley runoff and evaporative loss inputs produced a significant effect on future predictions. The proposed water conservation measures caused the predicted Salton Sea salinity for 2000 to greatly exceed 40,000 ppm, the level at which adverse effects to wildlife are believed to occur. The possible geothermal development also produced predicted salinities considerably above 40,000 ppm. The salinity predictions for solar ponds by themselves and in conjunction with geothermal development were below 45,000 ppm for 2000. The solar pond and geothermal combination also resulted in a predicted lowering of the “natural” water level by 5 to 7 fee

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05371.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:Lakes, marshes and wet meadows occur in the broad, flat, interdune valleys of the Nebraska Sandhills, a vegetation‐stabilized dune field underlain by sediments containing an enormous supply of groundwater. Hydrologic, geologic and possibly climatologic factors influence the chemical quality of lake water. Central and eastern lakes generally are in connection with the groundwater reservoir. The hydrologic nature of western lakes and the cause of their high alkalinity is not fully understood. Lakes in close proximity may vary in both their chemical characteristics and in the degree to which they change in size and depth over time. Climatic, hydrogeologic and natural lake‐aging processes of accumulation of organics appear to be primarily responsible for lake‐size varia

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05372.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:A Helley‐Smith pressure differential bedload sampler was used to measure bedload transport at consecutive riffle sections of a riffle‐pool‐riffle sequence on Bambi Creek, a small (154 ha), second‐order stream on Chichagof Island, Alaska, during four storms over a 2‐year period. Maximum bedload transport rate measured was 4920 kg/h at a streamflow of 2.35 m3/s corresponding to a storm having a 5‐year return interval. Transport of larger sediment (>8 mm) varied systematically with streamflow at the two sampling locations. At flows up to approximately bankfull, transport of large sediment was greatest at the upstream site; at flows above bankfull, transport of large sediment was greatest at the downstream site. The net import of large sediment to the pool during moderate stormflows and net export of large sediment from the pool during flows above bankfull may be related to a “convergence” or “reversal” of competence between the upstream riffle and subsequent pool at flows approximating bankfull stage. Cross‐sections monitored within the study reach indicate that stormflows resulted in net filling of the riffle sections and net scour of the pool; periods of low streamflow resulted in net scour of the riffles and n

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05373.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Book review in this ArticleRandom Functions in Hydrology, R. L. Bras and I. Rodriguez‐Iturbe.State of the Environment: An Assessment at Mid‐Decade.Siting Hazardous Waste Management Facilities, The Conservation Foundation. The Conservation Foundation, Chemical Manufacturers Assoc, and the National Audubon Society.Principles of Water Quality, Thomas D. Waite.Geomorphology, R. J. Chorley, S. A. Schumm, and D. E. Sug‐den.Surface Water Treatment for Communities in Developing Countries, C. R. Schulz and D. A. Okun.Analysis of Water Distribution Systems, Thomas M. Walski.California Riparian Systems, R. E. Warner and K. M. Hendrix (Editors).TVA: Fifty Years of Grass‐Roots Bureaucracy, E. C. Hargrove and P. K. Conkin (Editors).Fluvial Hydrology, S. Lawrence Dingman. W. H. FreemanGoing Sour: Science and Politics of Acid Rain, Roy Gould.Introduction to Environmental Engineering, M. L. DAvis and D. A. Cornwell.An Introduction to the World's Oceans, A. C. Duxbury and A. Duxbury.The Climatic Scene, M. J. Tooley and G. M. Sheail (Editors).Impounded Rivers: Perspectives for Ecological Management, Geoffrey E. Petts.Groundwater‐Leachate: Modeling/Monitoring/Sampling, P. N. Cheremisinoff, K. A. Gigliello, and T. K

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05374.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05375.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:By employing a set of criteria for classifying the capabilities of time series models, recent developments in time series analysis are assessed and put into proper perspective. In particular, the inherent attributes of a wide variety of time series models and modeling procedures presented by the authors of the 18 papers contained in this volume are clearly pointed out. Additionally, it is explained how these models can address many of the time series problems encountered when modeling hydrologic, water quality and other kinds of time series. For instance, families of time series models are now available for modeling series which may contain nonlinearities or may follow nonGaussian distributions. Based upon a sound physical understanding of a problem and results from exploratory data analyses, the most appropriate model to fit to a data set can be found during confirmatory data analyses by following the identification, estimation and diagnostic check stages of model construction. Promising future research projects for developing flexible classes of time series models for use in water resources applications are suggested.

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05376.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:water resources supply and demand time series consist of several or all of the four basic characteristics: tendency, intermittency, periodicity and stochasticity. Their importance changes from one type of variables to another. Historic developments of analysis of time series in hydrology have varied significantly over the past, from the stress on search for periodicities and persistence in annual series to the emphasis on the series stochastic properties. Supply and demand series are often highly interrelated, which fact is most often neglected in planning water resources systems in general, and water storage capacities in particular. The future of series analysis in water resources will likely be by a joint use of physically‐based structural analysis and the use of advanced methods of treating data by stochastic processes, statistical estimation and inference techniques. The most intriguing challenge of the future of this analysis may be the treatment of nonnormal, nonlinear and in general nonstationary hydrologic and water use time series. The proper treatment of complex multivariate processes will also challenge the specialists, especially for the purposes of transfer of information between data on variables at given points, or between data at several points of a given variable, or bot

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05377.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

ABSTRACT:A survey is given of recently developed models for continuous variate non–Gaussian time series. The emphasis is on marginally specific models with given correlation structure. Exponential, Gamma, Weibull, Laplace, Beta and Mixed Exponential models are considered for the marginal distributions of the stationary time series. Most of the models are random coefficient, additive linear models. Some discussion of the meaning of autoregression and linearity is given, as well as suggestions for higher–order linear residual analysis for non–Gaussian m

ISSN:1093-474X    

DOI:10.1111/j.1752-1688.1985.tb05378.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY