Management model for control of on-farm irrigation

A physically based model for the management and forecasting of irrigation water requirements at an on‐farm level is developed. The model includes mechanisms for simulating root and soil‐water movement, root growth, and crop yield. Model inputs and soil and crop parameters are easily attainable so that the model is usable in field situations. The management model is verified by calibrating it to a crop of cotton grown on an experimental plot at the University of California at Davis, then comparing the results of the model simulations to the field measured data for two alternate water treatments that were used to irrigate the experimental cotton crop. These verifications indicate that the soil‐water content distributions are simulated with a high degree of accuracy, and root‐density distributions are better simulated under moist soil conditions. Further analysis indicates that maintaining moist soil conditions during the bloom stage of cotton growth is critical for consistently high cotton crop yields.

[1]  Reinder A. Feddes,et al.  Simulation of field water uptake by plants using a soil water dependent root extraction function , 1976 .

[2]  Gedeon Dagan,et al.  Variability of yield of an irrigated crop and its causes: 1. Statement of the problem and methodology , 1988 .

[3]  J. A. Lutz,et al.  Row Spacing and Population Effects on Corn Yields 1 , 1971 .

[4]  H. Talpaz,et al.  A MACROSCOPIC‐SCALE MODEL OF WATER UPTAKE BY A NONUNIFORM ROOT SYSTEM AND OF WATER AND SALT MOVEMENT IN THE SOIL PROFILE , 1976 .

[5]  Wilfried Brutsaert,et al.  PROBABILITY LAWS FOR PORE-SIZE DISTRIBUTIONS , 1966 .

[6]  Miguel A. Mariño,et al.  Flow of Water Through Root-Soil Environment , 1988 .

[7]  Daniel Hillel,et al.  A Model of Root Growth and Water Uptake Accounting for Photosynthesis, Respiration, Transpiration, and Soil Hydraulics , 1983 .

[8]  Miguel A. Mariño,et al.  Model for simulating soil-water content considering evapotranspiration — Reply , 1978 .

[9]  W. R. Gardner,et al.  Water Uptake By Plants: II. The Root Contact Model , 1977 .

[10]  S. W. Childs,et al.  Model of Soil Salinity Effects on Crop Growth 1 , 1975 .

[11]  M. G. Huck,et al.  Modification and testing of a model simulating root and shoot growth as related to soil water dynamics , 1987 .

[12]  F. Molz,et al.  Application of an Extraction-Term Model to the Study of Moisture Flow to Plant Roots1 , 1971 .

[13]  S. P. Neuman,et al.  Field test of a modified numerical model for water uptake by root systems , 1974 .

[14]  E. R. Page,et al.  An empirical mathematical model to describe plant root systems , 1974 .

[15]  H. M. Taylor,et al.  MICROCOMPUTER SIMULATION MODEL OF SOIL WATER EXTRACTION BY SOYBEANS , 1983 .

[16]  E. McCoy,et al.  TOWARD UNDERSTANDING SOIL WATER UPTAKE BY PLANT ROOTS , 1984 .

[17]  H. Talpaz,et al.  NOTE SIMULATION OF ROOT GROWTH AND ITS EFFECT ON THE PATTERN OF SOIL WATER UPTAKE BY A NONUNIFORM ROOT SYSTEM , 1976 .