Wheat-fallow (W-F) is the predominant cropping system in the Great Plains, but the percent of precipitation stored as soil water (WSE) during fallow is frequently less than 25% with conventional tillage. No-till technology has improved potential WSE. Our objectives were to determine the effects of cropping system, landscape position (soil), and evaporative gradient (location) on WSE during inter-crop periods in intensified no-till cropping systems. Water storage efficiency was 48% during the wheat to corn fallow period in the 3- or 4-year rotational systems, contrasting sharply with the 22% WSE for the W-F system. The 3-year system, with a shorter fallow period (11 months), was just as effective in storing water as the long fallow period (14 months) in the WF system. Water storage efficiency was the lowest at the southern location, which had the highest potential evapotranspiration, but the contrasts among cropping systems remained. Toeslope soils had the highest WSE compared to summit or sideslope positions because of their opportunity to catch runoff water. The possibility exists for using even move intensive cropping systems than those examined in this study and this may mean that summer fallow could be eliminated with no-till practices.
