Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/1999
Publication Date: 11/1/2000
Citation: JABRO, J.D., ALVA, A.K., COCHRAN, J.E., DAVENPORT, J.R., BOYDSTON, R.A. SPATIAL AND TEMPORAL DISTRIBUTION OF SOIL WATER CONTENT IN A QUINCY SANDY SOIL. AGRONOMY ABSTRACTS, P. 200. 2000. Interpretive Summary: Most agricultural soils are not homogeneous units. Several soil characteristics vary spatially which need to be considered in managing crop production inputs to minimize the effects of growth limiting factors. Variability in soil water content was studied using a neutron probe, in a 20-acre irrigated field, to a depth of 120 cm, with center pivot irrigation. There was considerable variation in water content across the field. However, the pattern of soil moisture content distribution by depth showed insignificant differences over time.
Technical Abstract: Variability of soil properties can profoundly affect the management and production of agricultural land. Data on the variability of soil water content over space and time are an important input factor in the scheduling and management of irrigation systems. The central Columbia plateau of Washington State is characterized by mostly sandy soils and center pivot irrigation is frequently used to supplement the rainfall, which is relatively low in this region. A series of measurements of volumetric water content across the field to a depth of 120 cm in 20 cm increments was collected using the neutron probe method under irrigated potatoes cropping system. Spatial and temporal variabiity were assessed using several statistical methods. Considerable variations in water contents were found across the field. However, no significant variations were found throughout soil profile and over time.