Submitted to: Proceedings of the International Airborne Remote Sensing Conference
Publication Type: Proceedings
Publication Acceptance Date: September 1, 1999
Publication Date: N/A
Interpretive Summary: As limited water resources become more in demand, agriculture must find innovative ways to improve the efficiency of irrigation scheduling. The technique described herein utilizes images of surface temperature such as can be obtained from aircraft. A simple analysis of the variation in temperatures across the field can help farm managers identify field size areas needing irrigation, thereby conserving water. This approach can potentially save time, money, and water for irrigated agriculture.
Information on crop water stress is useful for such farm management decisions as scheduling irrigations and applying crop amendments. We derived a crop water stress index based simply on the variance of emitted thermal energy from irrigated crops detected by an airborne thermal sensor. This simple approach, termed the Histogram-derived Crop Water Stress Index (HCWSI), requires only an uncalibrated, uncorrected fine-resolution thermal image of the field. Results from a preliminary demonstration of HCWSI in irrigated cotton fields in Arizona showed that HCWSI was sensitive to both early and chronic crop water stress and to irrigation nonuniformity. With further testing and refinement, HCWSI may provide an inexpensive, reliable, and operational approach for farm- scale water management.