Many irrigators face the prospect that they will not be able to fully irrigate their crops. They are under pressure to develop cropping strategies as pumping capacities dwindle or water supplies become more restricted. These irrigators need to make long term and short term decisions about their deficit irrigation management strategies.
Multiple crops in rotation can be an economically viable strategy compared with monoculture when water is limited, but these alternatives need to be evaluated. The Crop Water Allocator (CWA) has been developed for irrigators to allocate limited water among selected crops. CWA calculates net economic returns from all possible combinations of crops, irrigation allocations among crops, and land allocations and ranks the net returns from maximum to minimum values.
After crops are selected, the irrigator needs to predict the capabilities of the irrigation system and the soil to provide water to the crop during the next irrigation season. They need plan their water applications to make the best economic use of available water. Major scheduling questions for deficit irrigation include: will pre-season irrigation be beneficial, and when should irrigation be initiated and terminated during the growing season. A computerized decision tool, the Crop Yield Predictor (CYP) has been developed to predict yields from alternative irrigation schedules. The user determines soil water status before or during the cropping season and formulates a potential schedule of irrigation dates and amounts.
The CWA and CYP are examples of transferring research based technology to irrigation management decision makers. The CWA and CYP are available at: www.mobileirrigationlab.com.
Publications related to CWA and CYP:
Klocke, N.L., L.R. Stone, S. Briggeman, D.A. Bolton. 2010. Scheduling deficit irrigation—crop yield predictor. J. of App. Eng. in Agric. 26(3):413-418.
Klocke, N.L., R.S. Currie, L.R. Stone, and D.A. Bolton. 2010. Planning for deficit irrigation. J. of App. Eng. In Agric. 26(3):405-412.
Klocke, N.L., L. R. Stone, G. A. Clark, T. J. Dumler, S. Briggeman. 2006. Water allocation model for limited irrigation. J. of App. Eng. In Agric. 22:3:381-389.