A statistical approach to estimating runoff in center pivot irrigation with crust conditions

There have been several proposals to evaluate potential runoff in center pivot irrigation, through the integration of time varying infiltration–precipitation rate curves, involving complex iterative procedures. Some methods use empirical infiltration functions, such as the Kostiakov equation. Others use physically based infiltration functions, such as the Green–Ampt equation. Another option is to use the Richards equation, describing the one-dimensional vertical infiltration of water into the soil for a specified irrigation event. This equation is generally accepted to provide a basis for comparison between other runoff estimation methods.