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The water balance of a sugar beet crop: A model and some experimental evidence
Author(s) -
van der Ploeg R. R.,
Beese F.,
Strebel O.,
Renger M.
Publication year - 1978
Publication title -
zeitschrift für pflanzenernährung und bodenkunde
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 87
eISSN - 1522-2624
pISSN - 0044-3263
DOI - 10.1002/jpln.19781410307
Subject(s) - evapotranspiration , transpiration , water balance , soil science , environmental science , water content , soil water , water potential , hydrology (agriculture) , precipitation , sugar beet , geotechnical engineering , agronomy , chemistry , meteorology , geology , physics , ecology , biochemistry , photosynthesis , biology
Abstract For a loes soil with sugar beets ( Beta vulgaris L.) a model was developed with which the difficult‐to‐measure components of the water balance equation can be determined. Basic component of the model is the unsaturated soil moisture flow equation. This equation is solved numerically by a finite difference method. As boundary condition at the soil surface, expressions for the potential and the actual transpiration and for the potential and the actual evaporation are used. Besides the hydraulic functions of the soil, standard meteorological measurements, together with leaf area index and root distribution data of the crop, enter the model. For a period of 316 days, calculated and measured soil suction values in 10 different soil depths, are compared as well as transpiration and seepage vaules. The comparison shows that the model provides acceptable results. The model calculations indicate that of the 519 mm of precipitation received during the 316‐day period, 503 mm were used for evapotranspiration and 119 mm left the soil profile as internal seepage.