Submitted to: Agricultural Water Management
Publication Type: Literature Review
Publication Acceptance Date: August 1, 1996
Publication Date: N/A
Technical Abstract: This review of the book, "Crop-Water-Simulation Models in Practice" explains that the book contains 18 papers organized into three sections: 1) six papers on soil water balance models for irrigation scheduling; 2) seven papers on crop growth and water balance simulation, mostly applied to irrigation and drainage problems; and 3) five papers concerning simulation of irrigation systems, emphasizing system management and design on a scale larger than individual fields. The papers present a broad view of modeling goals and strategies from the very specific and somewhat limited to models intended for general use under widely disparate conditions. There is also some discussion of differing philosophies and strategies aimed at similar goals. One example is the contrast of soil water balance models based on numerical solutions of the Richards equation with those based on Green-Ampt infiltration and a single or few soil layers which drain only when wetted to field capacity. Similarly, methods of computing reference evapotranspiration (ET) range from Priestly-Taylor to Penman-Monteith to Jensen-Haise formulations; and methods of computing crop ET range from using a reference ET and a crop coefficient to more physically based solutions depending on surface energy balances and direct estimation of crop and aerodynamic resistances. None of the papers presents a complete description of the subject computer program, something that is impossible in a single article about any substantial code, but most give a good view of the main governing equations and the tradeoffs and simplifying assumptions made in formulating the code. Also, most of the work is as near state-of-the-art as one is likely to find. All papers end with reference lists, some quite extensive.