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פותח על ידי קלירמאש פתרונות בע"מ -
Improved calibration of time domain reflectometry soil water content measurements
Year:
1993
Authors :
דסברג, שמואל
;
.
Volume :
57
Co-Authors:
Dirksen, C., Dept. of Water Resources, Wageningen Agricultural Univ., Wageningen, The Netherlands.
Dasberg, S., Dept. of Water Resources, Wageningen Agricultural Univ., Wageningen, The Netherlands.
Facilitators :
From page:
660
To page:
667
(
Total pages:
8
)
Abstract:
The purpose was to compare the Topp-Davis-Annan calibration equation with a theoretical (Maxwell-De Lor) and an empirical (fitting exponent α) mixing model for the four components: solid phase (s), tightly bound water (bw), free water, and air. Water content permittivity were measured, gravimetrically and by time domain reflectometry (TDR), on packed columns of 11 soils ranging from loess to pure bentonite. Topp yielded accurate values only for four soils, including illite. Maxwell-De Loor gave similar accuracy for seven soils, including attapulgite. Deviations from Topp can be accomodated by the Maxwell-De Loor equation. This makes it a better calibration equation than Topp. The empirical α model is sensitive to the unpredictable value of α and cannot accomodate anomalous behaviour. -from Authors
Note:
Related Files :
Flow measurement
Hydraulic models
Maxwell-De Loor equation
Soil mechanics
Soils
Time domain reflectometry (TDR)
עוד תגיות
תוכן קשור
More details
DOI :
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
Language:
אנגלית
Editors' remarks:
ID:
28009
Last updated date:
02/03/2022 17:27
Creation date:
17/04/2018 00:35
Scientific Publication
Improved calibration of time domain reflectometry soil water content measurements
57
Dirksen, C., Dept. of Water Resources, Wageningen Agricultural Univ., Wageningen, The Netherlands.
Dasberg, S., Dept. of Water Resources, Wageningen Agricultural Univ., Wageningen, The Netherlands.
Improved calibration of time domain reflectometry soil water content measurements
The purpose was to compare the Topp-Davis-Annan calibration equation with a theoretical (Maxwell-De Lor) and an empirical (fitting exponent α) mixing model for the four components: solid phase (s), tightly bound water (bw), free water, and air. Water content permittivity were measured, gravimetrically and by time domain reflectometry (TDR), on packed columns of 11 soils ranging from loess to pure bentonite. Topp yielded accurate values only for four soils, including illite. Maxwell-De Loor gave similar accuracy for seven soils, including attapulgite. Deviations from Topp can be accomodated by the Maxwell-De Loor equation. This makes it a better calibration equation than Topp. The empirical α model is sensitive to the unpredictable value of α and cannot accomodate anomalous behaviour. -from Authors
Scientific Publication
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