|
|
|
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
SPECIAL SECTION - ADVANCES IN MEASUREMENT AND MONITORING METHODS |
a J.M. Ham, Department of Agronomy, Kansas State University, Manhattan, KS 66506
b Plant and Soil Science Department, Texas Tech University, Lubbock, TX 79409
c Rocky Mountain Research Station, U.S. Forest Service, 240 W. Prospect Rd., Fort Collins, CO 80526
d Department of Biological and Agricultural Engineering, Kansas State University, Manhattan, KS 66506
Correspondence: * Corresponding author (gjk{at}ksu.edu).
Received for publication 19 March 2003.
The dual-probe heat-pulse (DPHP) method is useful for measuring water content (
) and change in water content (
) near the soil surface. The method has been evaluated in laboratory and greenhouse experiments, but not in a field setting. Our objective was to test the DPHP method under field conditions and for a range of soil properties. Twenty-five DPHP sensors and five monitoring stations were constructed and installed at five locations in northeastern Kansas to measure
and 
at 3-h intervals for 3 mo. In addition,
was estimated by coupling 
measurements with independent measurements of
obtained by soil sampling at sensor installation. Additional soil samples were collected from each location during the monitoring period to provide independent measurements of
. Regression of DPHP and independent
measurements revealed slight bias but substantial offset error (about 0.1 m3 m-3) in the DPHP method. The offset error could not be fully attributed to bias in any single input parameter, but could have been caused by a combination of biased parameters. Estimates of
from 
measurements also revealed slight bias, but offset error was considerably smaller. Use of a published empirical calibration for DPHP sensors almost completely eliminated this bias and further reduced the offset error to approximately 0.01 m3 m-3. Thus, the 
approach combined with use of the empirical calibration appears to have practical utility.
Abbreviations: DACS, data acquisition and control system DPHP, dual-probe heat-pulse
This article has been cited by other articles:
![]() |
T. Kamai, G. J. Kluitenberg, and J. W. Hopmans Design and Numerical Analysis of a Button Heat Pulse Probe for Soil Water Content Measurement Vadose Zone J., March 5, 2009; 8(1): 167 - 173. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Liu, B. Li, T. Ren, R. Horton, and B. C. Si Analytical Solution of Heat Pulse Method in a Parallelepiped Sample Space with Inclined Needles Soil Sci. Soc. Am. J., September 1, 2008; 72(5): 1208 - 1216. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Robinson, C. S. Campbell, J. W. Hopmans, B. K. Hornbuckle, S. B. Jones, R. Knight, F. Ogden, J. Selker, and O. Wendroth Soil Moisture Measurement for Ecological and Hydrological Watershed-Scale Observatories: A Review Vadose Zone J., February 25, 2008; 7(1): 358 - 389. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. H. Young, G. S. Campbell, and J. Yin Correcting Dual-Probe Heat-Pulse Readings for Changes in Ambient Temperature Vadose Zone J., January 23, 2008; 7(1): 22 - 30. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. M. DeSutter, T. J. Sauer, T. B. Parkin, and J. L. Heitman A Subsurface, Closed-Loop System for Soil Carbon Dioxide and Its Application to the Gradient Efflux Approach Soil Sci. Soc. Am. J., January 11, 2008; 72(1): 126 - 134. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Knight, W. Jin, and G. J. Kluitenberg Sensitivity of the Dual-Probe Heat-Pulse Method to Spatial Variations in Heat Capacity and Water Content Vadose Zone J., October 8, 2007; 6(4): 746 - 758. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Liu, B. Li, T. Ren, and R. Horton Analytical Solution of the Heat Pulse Method in a Parallelepiped Sample Space Soil Sci. Soc. Am. J., August 27, 2007; 71(5): 1607 - 1619. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Heitman, R. Horton, T. Ren, and T. E. Ochsner An Improved Approach for Measurement of Coupled Heat and Water Transfer in Soil Cells Soil Sci. Soc. Am. J., May 16, 2007; 71(3): 872 - 880. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. E. Ochsner, T. J. Sauer, and R. Horton Field Tests of the Soil Heat Flux Plate Method and Some Alternatives Agron. J., June 5, 2006; 98(4): 1005 - 1014. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. K. Olmanson and T. E. Ochsner Comparing Ambient Temperature Effects on Heat Pulse and Time Domain Reflectometry Soil Water Content Measurements Vadose Zone J., May 26, 2006; 5(2): 751 - 756. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. R. Evett and G. W. Parkin Advances in Soil Water Content Sensing: The Continuing Maturation of Technology and Theory Vadose Zone J., November 11, 2005; 4(4): 986 - 991. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Ren, Z. Ju, Y. Gong, and R. Horton Comparing Heat-Pulse and Time Domain Reflectometry Soil Water Contents from Thermo-Time Domain Reflectometry Probes Vadose Zone J., November 11, 2005; 4(4): 1080 - 1086. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.M. Ham and E.J. Benson Response to "Comments on 'On the Construction and Calibration of Dual-Probe Heat Capacity Sensors'" Soil Sci. Soc. Am. J., August 25, 2005; 69(5): 1666 - 1667. [Full Text] [PDF] |
||||
![]() |
Y. Mori, J. W. Hopmans, A. P. Mortensen, and G. J. Kluitenberg Estimation of Vadose Zone Water Flux from Multi-Functional Heat Pulse Probe Measurements Soil Sci. Soc. Am. J., April 11, 2005; 69(3): 599 - 606. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Ham and E. J. Benson On the Construction and Calibration of Dual-Probe Heat Capacity Sensors Soil Sci. Soc. Am. J., July 1, 2004; 68(4): 1185 - 1190. [Abstract] [Full Text] [PDF] |
||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |