An intraseasonal irrigation decision aid : Texas High Plains /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1991.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | Water is an important input in the production of agricultural crops. As the demand for water by cities, agriculture, industry, and recreational interests increases, water demand has begun to exceed supply in some areas. Sticky prices and unclear water rights cause market inefficiencies in many cases. Increased efficiency in water use by all users can reduce some of the scarcity. Farmers in particular can benefit from improved technology to increase their efficiency in irrigation. This study develops an easy-to-use decision aid to assist farmers in optimally allocating individual irrigations within a growing season. A multi-year/multi-crop growth simulation model known as EPIC was used to simulate corn and sorghum yield to number and timing of fixed irrigation quantities on the hardland soils of the Texas High Plains. This information was incorporated into a dynamic programming (DP) model that determined the expected increase in net income associated with an irrigation at 15 different decision stages during the growing season. The expected value of each irrigation depends on the stage of the season, the amount of water stored in the soil, and the condition of the crop, as well as, water cost and output price. Preplant irrigations and fixed amounts of nitrogen were I applied to both crops in every simulation so as not to impact upon the expected value of seasonal irrigations. The DP model prints 15 decision tables, one for each of the 15 decision stages, for each crop. These tables display the expected contribution to net returns of an irrigation in the current stage for each possible combination of soil water and crop condition. The irrigation decision aid developed here is easy to apply. The farmer merely needs to measure water stored in the top 8 inches of soil at each decision stage as the irrigation season progresses. The expected contribution to net returns of an irrigation in the current stage is then determined using the DP table representing the current stage, the current soil water measurement, and the current crop condition. A proxy is used for crop condition and is calculated using soil water and irrigation information from decision stages prior to the current stage. Simulation techniques revealed that using the decision aid developed in this dissertation, when compared to a full irrigation strategy, should maintain net returns on corn and sorghum in the study area while reducing the number of irrigations applied per year. It may also reduce the producers risk on corn production... |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Agricultural Economics." |
| Physical Description: | xiii, 119 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |