|Pringle Iii, H -|
|Samson, S -|
|Schmidt, A -|
Submitted to: Decennial National Irrigation Symposium
Publication Type: Proceedings
Publication Acceptance Date: September 22, 2010
Publication Date: December 5, 2010
Citation: Sassenrath, G.F., Pringle Iii, H.C., Fisher, D.K., Samson, S., Schmidt, A.M. 2010. Development of Irrigation Scheduling Tools for the Humid, High-Rainfall Environment of the Lower Mississippi Delta. Proceedings of the Decennial National Irrigation Symposium, December 5-8, Phoenix, AZ. Paper Number IRR10-9797. Interpretive Summary: Currently, easy to use, web-based irrigation scheduling systems are available for the humid growing environments of the Mid-South. Common irrigation scheduling systems rely on soil or weather data to estimate crop water use, and are more commonly calibrated for dry growing environments. Increasing use of water in the Mid-South has led to depletion of water levels in the aquifer, with no guidelines in place for farmers as to when and how much to irrigate. The web-based system pulls information from national soil and weather data bases into a central server. Farmers select fields, and input irrigation system specifications, rainfall and irrigation applications. The scheduler calculates crop water use from weather data, and indicates when soil available moisture is depleted, requiring an irrigation. The irrigation scheduling system is an important management tool for improving crop production systems, while conserving precious water resources. By integrating nationally available data bases, farmers will be able to quickly import a wide range of information for their farms. By linking with national weather databases, the system will predict potential future rainfall, reducing potential excessive irrigation of crops. Training materials are also being developed to transfer the technology to producers.
Technical Abstract: Irrigation in hot, humid areas is particularly challenging because irrigation must be applied in a timely manner to prevent yield loss due to crop water stress, yet avoid flooding should a rain event follow an irrigation. Moreover, it is difficult to detect the onset of crop water stress under environmental conditions that limit evaporative cooling. Our goal is to develop reliable, easy to use irrigation scheduling tools that integrate crop monitoring and accurate weather predictions to improve the timing and application of irrigation in humid, high rainfall environments for better water management. The irrigation decision support system is based on calculations of crop water use from weather data collected from weather stations throughout Mississippi, using crop coefficients developed from weighing lysimeters. A checkbook method is used to indicate when supplemental irrigation is needed based on plant available water and crop water use. This is integrated with other publically available, spatially registered farm and soil databases to develop site specific irrigation scheduling recommendations. The irrigation decision support system will be delivered to producers through an easy to use and readily accessible format. Training materials will be developed and presented to producers through on-site training and other standard Extension mechanisms.