Infiltration is the process by which water enters the soil. It
separates water into two major hydrologic components, surface
runoff and subsurface recharge. Accurate determination of infiltration rates is essential for reliable prediction of surface runoff
(Diamond and Thomas, 2003). The main goal of operating an irrigation system is to apply an adequate water depth over the field
with minimum runoff. To avoid runoff problems, it is necessary to
have a good understanding of soil infiltration characteristics when
designing and managing infiltration systems. Sprinkler irrigation is
becoming a preferred method as the water available for irrigation
around the world becomes increasingly scarce, especially in arid
and semiarid regions. Center-pivot is one of the irrigation systems
that apply water with high-application rates, especially when operating with low-pressure sprinklers. The use of this irrigation system
in soils with low infiltrability usually produces large amounts of
runoff and soil erosion problems (Silva, 2007). Therefore, prediction
of potential runoff is a very useful tool for proper design and management of center-pivot irrigation systems. For sprinkler irrigation
systems, the soil infiltration rate determines the design application
rate to avoid or minimize surface runoff, particularly in areas where
water conservation is essentially required (AL-Ghobari, 2002). Infiltration is affected by properties of irrigation water and soil factors.