Journal of Irrigation and Drainage Engineering: Recent submissions

Now showing items 3421-3440 of 3826

    • Land‐Grading Design by Using Nonlinear Programming 

      Safa N. Hamad; Ahmed M. Ali (American Society of Civil Engineers, 1990)
      Land grading is an important and necessary operation for successful and efficient surface irrigation. Currently, most lands are graded or reshaped to form a plane surface with uniform slopes in one or two directions. In ...

    • Estimating Irrigation Diversions for Major Texas Rice‐Growing Area 

      Quentin W. Martin (American Society of Civil Engineers, 1990)
      The Lower Colorado River Authority (LCRA) of Texas provides an average of 530,000 acre‐ft annually for rice cultivation. To estimate water needs better, predictive equations were developed, using least‐squares regression, ...

    • Characterizing Cyclic Water‐Level Fluctuations in Irrigation Canals 

      Kenneth C. Mitchell; Larry G. James; Steve Elgar; Marvin J. Pitts (American Society of Civil Engineers, 1990)
      A technique is demonstrated for characterizing water‐level fluctuations in irrigation canals using amplitude spectral estimates obtained with a fast Fourier transform. The technique, which is often used to analyze mechanical ...

    • Monitoring and Evaluation of Irrigation Projects 

      Asit K. Biswas (American Society of Civil Engineers, 1990)
      Monitoring and evaluation of irrigation projects has been a neglected subject, but must play a more important role in the future if the irrigation management process is to be improved. The process is complex, since a large ...

    • Effective Rainfall Estimation Methods 

      Avinash S. Patwardhan; John L. Nieber; Eldon L. Johns (American Society of Civil Engineers, 1990)
      Numerous methods for estimating effective rainfall have been proposed in the past, including: direct measurement techniques; empirical methods; and soil water balance methods. The best estimates of effective rainfall can ...

    • Pump Test Analysis of Confined Aquifer 

      Prabhata K. Swamee; Chandra Shekhar P. Ojha (American Society of Civil Engineers, 1990)
      The storage coefficient and transmissivity are important aquifer parameters that are useful in assessing the ground‐water potential of an aquifer. For a nonleaky confined aquifer, these parameters can be determined with ...

    • Analytical Model for Furrow Irrigation 

      Fang X. Yu; Vijay P. Singh (American Society of Civil Engineers, 1990)
      An analytical model is developed to simulate all phases of furrow irrigation. The model transforms any real furrow cross section shape to a discharge‐equivalent semicircular shape, and can therefore be applied to any form ...

    • Design of Hydraulic Jump Chambers 

      Scott F. Korom; Simsek Sarikelle; Andrew L. Simon (American Society of Civil Engineers, 1990)
      The results of a model study of an energy dissipator, called a hydraulic jump chamber, are given. This structure uses precast concrete blocks secured to their inside periphery. The results showed that three sets of blocks ...

    • Effects of Climate Change on U.S. Irrigation 

      Dean F. Peterson; Andrew A. Keller (American Society of Civil Engineers, 1990)
      Warming of the global atmosphere by 2°‐5° C, and regional changes in precipitation by mid 21st century as greenhouse gases double, is expected. A composite model predicts the consequences on the geography of U.S. irrigation. ...

    • Xiangtan Q‐Type Automatic Hydraulic Flap Gate 

      Luo Guang Jiong (American Society of Civil Engineers, 1990)
      The automatic operation of Xiangtan Q‐type gate is based on hydraulic pressure only. As the upstream water rises above the top of gate, the gate opens automatically to safeguard the banks against flood. As the water level ...

    • Systematic Procedure for Evaluating Partial Areas of Watershed Runoff 

      Walter C. Boughton (American Society of Civil Engineers, 1990)
      A method is presented by which the proportions of a watershed that contribute surface runoff in different storms and at different times during the same storm can be determined by analysis of rainfall and runoff records. ...

    • Hourly ET Model Calibration with Eddy Flux and Energy Balance Data 

      Michael A. Kizer; Ronald L. Elliott; John F. Stone (American Society of Civil Engineers, 1990)
      The Penman equation for estimating hourly evapotranspiration (ET) of an alfalfa reference crop was calibrated for both daytime and nighttime conditions. Hourly net radiation, sensible heat flux, and soil heat flux were ...

    • Validating GLEAMS with Field Data for Fenamiphos and Its Metabolites 

      R. A. Leonard; W. G. Knisel; F. M. Davis; A. W. Johnson (American Society of Civil Engineers, 1990)
      The GLEAMS (ground water loading effects of agricultural management systems) model was modified to simulate the generation and degradation of pesticide metabolites. Translocation of the metabolites within and through the ...

    • Preferential Movement of Pesticides and Tracers in Agricultural Soils 

      Tammo S. Steenhuis; Ward Staubitz; Marc S. Andreini; Jan Surface; Tom L. Richard; Robert Paulsen; Nigel B. Pickering; James R. Hagerman; Larry D. Geohring (American Society of Civil Engineers, 1990)
      Carbofuran, alachlor, atrazine, bromide (a tracer), and nitrate are applied to two tile‐drained plots of com, one of which is conventionally tilled and another that is no‐till. Soil water samples are collected from the ...

    • Discussion of “<i>Terminology for Describing On‐Farm Irrigation Water Demands</i>” by David h. Manz (May, 1988, Col. 114 No. 2) 

      John L. Merriam (American Society of Civil Engineers, 1990)

    • Closure to “<i>Adjusted F Factor for Multiple‐Outlet Pipes</i>” by Edmar José Scaloppi (February, 1988, Col. 114, NO. 1) 

      Edmar José Scaloppi (American Society of Civil Engineers, 1990)

    • Aldicarb in Vadose Zone: Review 

      J. A. Stover; J. C. Guitjens (American Society of Civil Engineers, 1990)
      The literature was reviewed regarding the sorption and transport of a nonionic organic pesticide aldicarb, an extremely toxic and relatively water soluble carbamate insecticide that has been detected in ground water across ...

    • Transient Hydraulic Model for Simulating Canal‐Network Operation 

      F. N. Gichuki; W. R. Walker; G. P. Merkley (American Society of Civil Engineers, 1990)
      Renewed interest in the role of delivery networks in farm‐level water‐use efficiency has prompted the development of a transient hydraulic simulation model for improving the operation and design of irrigation canal networks. ...

    • Atrazine and Metolachlor in Subsurface Drain Water in Louisiana 

      L. M. Southwick; G. H. Willis; R. L. Bengston; T. J. Lormand (American Society of Civil Engineers, 1990)
      Atrazine and metolachlor are applied preemergent to corn in plots that are either drained (10‐cm plastic tubes 1‐m deep) or undrained. Herbicide concentrations in the soil profile down to 30 cm and in the drain water are ...

    • Sorption and Transport of Pesticides in Ground Water: Critical Review 

      David A. Sabatini; T. Al Austin (American Society of Civil Engineers, 1990)
      The appearance of pesticides in ground water necessitates the accurate prediction of pesticide transport in ground water. Adsorption and desorption are major mechanisms affecting the movement of pesticides in ground water. ...