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OLS Field Name OLS Field Data
Main Title Soil Water Model for Two Constrasting Tillage Systems.
Author Shanholt, V. O. ; Lillar, J. H. ;
CORP Author Virginia Polytechnic Inst., Blacksburg. Water Resources Research Center.
Year Published 1970
Report Number Bull-38; OWRR-A-018-VA; 02883,; A-018-VA(3)
Stock Number PB-196 364
Additional Subjects ( Soil water ; Evapotranspiration) ; ( Evapotranspiration ; Mathematical models) ; Simulation ; Corn ; Rainfall ; Water balance ; Vegetation ; Density ; Computer programs ; Cultivation ; Correlation techniques ; Water consumption ;
Library Call Number Additional Info Location Last
NTIS  PB-196 364 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/23/1988
Collation 216p
Abstract Techniques were developed to simulate the soil-plant environment as a semi-dynamic hydrologic system. Exponential expressions give reasonable estimates of soil evaporation prior to corn plant emergence. A family of nonlinear curves were used to estimate evapotranspiration after emergence. These curves assumed that pan evaporation was the integrated result of atmospheric demands. Precipitation excess was estimated from an exponential expression using total water storage capacity in the Ap or A soil horizon. Corn plant heights were simulated with a 2-part nondimensional exponential relationship. Rainfall interception was assumed to be a function of rainfall, plant height, and density of cover. Vertical water movement through the soil was assumed to be related to its saturated hydraulic conductivity. All aspects of the model were programmed in the Fortran language for an IBM 360 Computer. A comparision of simulated with observed data indicates very good agreement. With few exceptions, the simulated results were well within sampling variation. (WRSIC abstract)
PUB Date Free Form Oct 70,
Category Codes 8H; 52J
NTIS Prices PC A10 MF A01
Document Type NT
Cataloging Source NTIS/MT
Control Number 326514874
Origin NTIS
Type CAT