The Effect of Soil Surface Curvature on Moisture and Yield—beer Sheba Observation

Moisture content measured in the soil correlated strongly with the curvature of the soil surface. At the concave parts of the landscape, the moisture content was as high as 14 percent, and grain yields were as high as 1734 kilograms per hectare. At the convex parts, the moisture content was as low as 5 percent, and the grain yields were as low as 408 kilograms per hectare. The correlation coefficient between the measured moisture and the calculated surface curvature was 0.9 and was significant at the 0.1 percent level. The observation tends to support our theory about the horizontal flow component of infiltrating water. The new theory and the supporting observations point toward an important source of nonuniformities in moisture distribution in nonleveled fields, which nonuniformities are far greater than those caused by common irrigation systems.