Potential to Use Limited Irrigation and Conservation Agriculture to Adapt to Drought and Climate Change.

A likely impact of climate change in the western U.S. will be a reduction in irrigation water supplies.  With competing demands on limited supplies, irrigated agriculture must maximize productivity and profits per unit of water consumed.  We are refining water production functions (yield per unit water) for crops grown in the high plains to help determine how to maximize water productivity and derive the most value from this limited resource.  This information can also be used by growers to set a value for water transfers to alternative uses.  Four years of field trials indicate that, in the high plains, regulated deficit irrigation can increase water productivity per unit irrigation water applied, but fully irrigating reduced area will be more productive per unit water consumed, or ET.  Thus, the most productive water allocation for a grower depends on how states regulate water use.