Calibration and Application of Aquaflex TDT Soil Water Probes to Measure the Soil Water Dynamics of Agricultural Topsoil in Southwest Germany
Publication: Journal of Irrigation and Drainage Engineering
Volume 141, Issue 6
Abstract
Soil water plays a key role in crop growth and yield formation. A sustainable irrigation management depends on a reliable soil water monitoring. The present study was conducted to derive site-specific and pedotransfer calibrations for Aquaflex time domain transmission (TDT) soil water sensors and to test their performance under field conditions. In spring 2009, two soil moisture networks were installed in the Kraichgau region and in the Swabian Alb, southwest Germany. Each network consists of 21 stations, each equipped among others with an Aquaflex TDT sensor installed 15-cm-deep in the soil. At each station, soil samples were taken and analyzed for the gravimetric soil water content, bulk density, soil texture, electrical conductivity, pH, and organic nitrogen and carbon content. The factory calibration delivered highly biased soil water contents [ (Vol.) %]. The root mean square errors (RMSEs) were high, reaching on average 8.3 and 12.6 Vol.% in Kraichgau and Swabian Alb, respectively. The RMSEs of pedotransfer calibrations declined to 3.7 Vol.% in Kraichgau and to 3.4 Vol.% in Swabian Alb. In both regions, the slope of the calibration curve was affected by soil bulk density. High-leverage independent variables affecting the intercept were electrical conductivity in Kraichgau and silt fraction in Swabian Alb. Site-specific calibrations performed best. On average, the RMSE in Kraichgau was 3.0 Vol.%, in Swabian Alb 1.9 Vol.%. The pedotransfer-based approach proposed in the present study is a good compromise between labour effort and accuracy for soil landscapes with similar texture and properties.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
We gratefully acknowledge the funding of the project by the German Research Foundation (DFG) in the frame of PAK 346 Structure and functions of agricultural landscapes under climate change—processes and projections on a regional scale and the research unit FOR 1695 Regional climate change. Moreover, we are thankful to 41 local farmers of Kraichgau and Swabian Alb for their willingness to support our research.
References
Alletto, L., and Coquet, Y. (2009). “Temporal and spatial variability of soil bulk density and near-saturated hydraulic conductivity under two contrasted tillage management systems.” Geoderma, 152(1–2), 85–94.
Baker, J. M., and Spaans, E. J. A. (1994). “Measuring water exchange between soil and atmosphere with TDR-microlysimetry.” Soil Sci., 158(1), 22–30.
Ball, B. C., Campbell, D. J., Douglas, J. T., Henshall, J. K., and O’Sullivan, M. F. (1997). “Soil structural quality, compaction and land management.” Eur. J. Soil Sci., 48(4), 593–601.
Biernath, C., et al. (2011). “Evaluating the ability of four crop models to predict different environmental impacts on spring wheat grown in open-top chambers.” Eur. J. Agron., 35(2), 71–82.
Bogena, H. R., Herbst, M., Huisman, J. A., Rosenbaum, U., Weuthen, A., and Vereecken, H. (2010). “Potential of wireless sensor networks for measuring soil water content variability.” Vadose Zone J., 9(4), 1002–1013.
Bundesamt für Kartographie und Geodäsie (BKG). (2014). 〈http://www.geodatenzentrum.de/geodaten/gdz_rahmen.gdz_div〉.
Dirmeyer, P. A., and Brubaker, K. L. (1999). “Contrasting evaporative moisture sources during the drought of 1988 and the flood of 1993.” J. Geophys. Res., 104(D16), 19383–19397.
Evett, S. R., Tolk, J. A., and Howell, T. A. (2006). “Soil profile water content determination: Sensor accuracy, axial response, calibration, temperature dependence, and precision.” Vadose Zone J., 5(3), 894–907.
Gong, Y., Cao, Q., and Sun, Z. (2003). “The effects of soil bulk density, clay content and temperature on soil water content measurement using time-domain reflectometry.” Hydrol. Processes, 17(18), 3601–3614.
Gutmann, E. D., and Small, E. E. (2007). “A comparison of land surface model soil hydraulic properties estimated by inverse modeling and pedotransfer functions.” Water Resour. Res., 43(5), W05418.
Harlow, R. C., Burke, E. J., and Ferre, T. P. A. (2003). “Measuring water content in saline sands using impulse time domain transmission techniques.” Vadose Zone J., 2(3), 433–439.
Harter, T., and Hopmans, J. W. (2004). “Role of vadose zone flow processes in regional scale hydrology: Review, opportunities and challenges.” Unsaturated zone modeling: Progress, challenges and applications, R. A. Feddes, G. H. De Rooij, and J. C. van Dam, eds., Kluwer Academic, Dordrect, Netherlands, 179–210.
Hedley, C. B., and Yule, I. J. (2009). “A method for spatial prediction of daily soil water status for precise irrigation scheduling.” Agric. Water Manage., 96(12), 1737–1745.
Hollinger, S. E., and Isard, S. A. (1994). “A soil moisture climatology of Illinois.” J. Climatol., 7(5), 822–833.
Hook, W. R., Ferre, T. P. A., and Livingston, N. J. (2004). “The effects of salinity on the accuracy and uncertainty of water content measurement.” Soil Sci. Soc. Am. J., 69(3), 47–56.
Ilstone, B. G., Basara, J. B., Fiebrich, C. A., Crawford, K. C., and Hunt, E. (2008). “Mesoscale monitoring of soil moisture across a statewide network.” Am. Meteorolog. Soc., 25(2), 167–182.
Ingwersen, J., et al. (2011). “Comparison of Noah simulations with eddy covariance and soil water measurements at a winter wheat stand.” Agric. For. Meteorol., 151(3), 345–355.
Leib, B. G., Jabro, J. D., and Matthews, G. R. (2003). “Field evaluation and performance comparison of soil moisture sensors.” Soil Sci., 168(6), 396–408.
McCready, M. S., Dukes, M. D., and Miller, G. L. (2009). “Water conservation potential of smart irrigation controllers on St. Augustinegrass.” Agric. Water Manage., 96(11), 1623–1632.
Mittelbach, H., Casini, F., Lehner, I., Teuling, A. J., and Seneviratne, S. I. (2011). “Soil moisture monitoring for climate research: Evaluation of a low-cost sensor in the framework of the Swiss soil moisture experiment (SwissSMEX) campaign.” J. Geophys. Res. Atmos., 116(D5), D05111.
Miyamoto, T., Kobayashi, R., Annaka, T., and Chikushi, J. (2001). “Applicability of multiple length TDR probes to measure water distributions in an Andisol under different tillage systems in Japan.” Soil Tillage Res., 60(1–2), 91–99.
Morari, F., and Giardini, L. (2002). “Irrigation automation with heterogeneous vegetation: The case of the Padova botanical garden.” Agric. Water Manage., 55(3), 183–201.
Moriasi, D. N., Arnold, J. G., Van Liew, M. W., Bingner, R. L., Harmel, R. D., and Veith, T. L. (2007). “Model evaluation guidelines for systematic quantification of accuracy in watershed simulations.” Trans. ASABE, 50(3), 885–900.
Nash, J. E., and Sutcliffe, J. V. (1970). “River flow forecasting through conceptual models. Part I. A discussion of principles.” J. Hydrol., 10(3), 282–290.
PASW SPSS Version 18 [Computer software]. Armonk, NY, IBM Corporation.
Payero, J. O., Tarkalson, D. D., and Irmak, S. (2006). “Use of time domain reflectometry for continuous monitoring of nitrate-nitrogen in soil and water.” Appl. Eng. Agric., 22(5), 689–700.
Plauborg, F., Iversen, B. V., and Lærke, P. E. (2005). “In situ comparison of three dielectric soil moisture sensors in drip irrigated sandy soils.” Vadose Zone J., 4(4), 1037–1047.
Qu, W., Bogena, H. R., Huisman, J. A., and Vereecken, H. (2013). “Calibration of a novel low-cost soil water content sensor based on a ring oscillator.” Vadose Zone J., 12(2), 0139–0149.
Robinson, D. A., et al. (2008). “Soil moisture measurement for ecological and hydrological watershed-scale observatories: A review.” Vadose Zone J., 7(1), 358–389.
Robinson, D. A., Jones, S. B., Wraith, J. M., Or, D., and Friedman, S. P. (2003). “A review of advances in dielectric and electrical conductivity measurement in soils using time domain reflectometry.” Vadose Zone J., 2(4), 444–475.
Robock, A., et al. (2000). “The global soil moisture data bank.” Bull. Am. Meteorol. Soc., 81(6), 1281–1299.
Robock, A., et al. (2003). “Evaluation of the North American land data assimilation system over the southern great plains during the warm season.” J. Geophys. Res. Atmos., 108(D22), GCP 7–GCP 21.
Rosenbaum, U., Huisman, J. A., Vrba, J., Vereecken, H., and Bogena, H. R. (2011). “Correction of temperature and electrical conductivity effects on dielectric permittivity measurements with ECH2O sensors.” Vadose Zone J., 10(2), 582–593.
Scheffer, F., and Schachtschabel, P. (2008). Soil science handbook, 15. Auflage. Spektrum Akademischer, Heidelberg.
Schlichting, E., Blume, H. P., and Stahr, K. (1995). Soil science practical cource—Implementation to pedology for ecology, land and geology scientists, Blackwell Wiss, Berlin.
Schwartz, B. F., Schreiber, M. E., Pooler, P. S., and Rimstidt, J. D. (2008). “Calibrating access-tube time domain reflectometry soil water measurements in deep heterogeneous soils.” Soil Sci. Soc. Am. J., 72(4), 917–930.
Stangl, R., Buchan, G. D., and Loiskandl, W. (2009). “Field use and calibration of a TDR-based probe for monitoring water content in a high-clay landslide soil in Austria.” Geoderma, 150(1–2), 23–31.
Streat Instruments Ltd. (2003). “Aquaflex sensor part # SI.99.” Instruction manual, 〈http://www.streatsahead.com/Pages/Aquaflex%20level2/Product%20Notes/SI_99productnote.pdf〉 (Apr. 16, 2003).
Topp, G. C., Davis, J. L., and Annan, A. P. (1980). “Electromagnetic determination of soil water content: Measurements in coaxial transmission lines.” Water Resour. Res., 16(3), 574–582.
Weaver, C. P., and Avissar, R. (2001). “Atmospheric disturbances caused by human modification of the landscape.” Bull. Am. Meteorolog. Soc., 82(2), 269–281.
Whalley, W. R., Cope, R. E., Nicholl, C. J., and Whitmore, A. P. (2004). “In-field calibration of a dielectric soil moisture meter designed for use in an access tube.” Soil Use Manage., 20(2), 203–206.
World Resources Reports (WRB). (2006). “WRB and food and agricultural organization of the united nations. World reference base for soil resources.” World Resources Rep. 103, Rome.
Wraith, J. M., Robinson, D. A., Jones, S. B., and Long, D. S. (2005). “Spatially characterizing apparent electrical conductivity and water content of surface soils with time domain reflectometry.” Comp. Electron. Agric., 46(1–3), 239–261.
Zacharias, S., et al. (2011). “A network of terrestrial environmental observatories in Germany.” Vadose Zone J., 10(3), 955–973.
Zhu, J., and Liang, X. (2005). “Regional climate model simulation of U.S. soil temperature and moisture during 1982–2002.” J. Geophys. Res. Atmos., 110(D24), 1–12.
Information & Authors
Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 141 • Issue 6 • June 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: May 16, 2014
Accepted: Oct 1, 2014
Published online: Nov 11, 2014
Discussion open until: Apr 11, 2015
Published in print: Jun 1, 2015
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.