Comparison of Laboratory and Field Calibration of a Soil-Moisture Capacitance Probe for Various Soils
Publication: Journal of Irrigation and Drainage Engineering
Volume 138, Issue 4
Abstract
Throughout the American west, irrigated agriculture has been targeted to increase water-use efficiency because of increased urban demands. Soil-moisture sensors offer a method to achieve efficiency improvements, but have found limited use primarily because of high cost and lack of soil-specific calibration equations. In this paper, the Decagon EC-20 soil-moisture sensor (a low-cost capacitance sensor) has been examined and a unique laboratory-calibration method has been developed. Field-and laboratory-calibration equations were developed for six soil types (sand, sandy loam, silt loam, loam, clay loam, and clay) in the Middle Rio Grande Valley for alfalfa and grass hay fields. The average absolute error in volumetric water content for field calibration was , and for the laboratory calibration. The factory-calibration equation for the EC-20 was also evaluated and found to yield an average absolute error of . In this study, it was found that the EC-20 is a reliable, cost-effective, and accurate sensor, and it is recommended that the laboratory-calibration method presented in this paper be used to obtain maximum accuracy. It is also recommended that the field calibration of the EC-20 soil-moisture sensor be foregone, as this type of calibration exhibits large error rates that are associated with colocation of samples, voids, organic residues, and root densities. Additionally, it was found that the field-calibration method was time-consuming, covered a small range of moisture content values, and was destructive to the area around installed sensors, which could lead to additional measurement errors.
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Acknowledgments
The authors would like to thank the staff of the Middle Rio Grande Conservancy District, especially Matt Martinez for his assistance in installing the EC-20 probes. The authors would also like to thank the New Mexico Interstate Stream Commission and the Endangered Species Act Collaborative Program for the funding to undertake this research. The advice and assistance of Gaylon Cambell, Doug Cobos, and TJ Clevenger of Decagon Devices are also recognized. The comments of Dr. Terence Podmore at Colorado State University greatly improved the manuscript. Finally, the authors would like to thank two anonymous reviewers whose comments greatly improved the manuscript.
References
Bandaranayake, W. M., Borhan, M. S., and Holeton, J. D. (2007). “Performance of a capacitance-type soil water probe in well-drained sandy soil.” Soil Sci. Soc. Am. J.SSSJD4, 71(3), 993–1002.
Bartoli, F., Regalado, C. M., Basile, A., Buurman, P., and Coppola, A. (2007). “Physical properties in European volcanic soils: A synthesis and recent developments.” Soils of volcanic regions in Europe, Springer-Verlag, Berlin, 515–537.
Baumhardt, R. L., Lascano, R. J., and Evett, S. R. (2000). “Soil material, temperature, and salinity effects on calibration of multisensor capacitance probes.” Soil Sci. Soc. Am. J.SSSJD4, 64(6), 1940–1946.
Borhan, M. S., Parsons, L. R., and Bandaranayake, W. (2004). “Evaluation of a low cost capacitance ECH2O soil moisture sensor for citrus in a sandy soil.” 25th Int. Irrigation Show, ICT International, Armidale, NSW, Australia, 447–454.
Bosch, D. D. (2004). “Comparison of capacitance-based soil water probes in coastal plain soils.” Vadose Zone J., 3(4), 1380–1389.VZJAAB
Campbell, C. S. (2002). Response of ECH2O soil moisture sensor to temperature variation, application note, Decagon Devices, Pullman, WA.
Christensen, N. B. (2005). “Irrigation management using soil moisture monitors.” Proc. Western Nutrient Management Conf., Oregon State Univ., Corvallis, OR, Vol. 6, 46–53.
Decagon Devices (2006a). “ECH2O dielectric probes vs time domain reflectometers (TDR).” Application Note, Pullman, WA.
Decagon Devices (2006b). ECH2O soil moisture sensor operator's manual for models EC-20, EC-10 and EC-5 version 5, Pullman, WA.
Evett, S. R., and Steiner, J. L. (1995). “Precision of neutron scattering and capacitance type soil water content gauges from field calibration.” Soil Sci. Soc. Am. J.SSSJD4, 59(4), 961–968.
Fares, A., Buss, P., Dalton, M., El-Kadi, A. I., and Parsons, L. R. (2004). “Dual field calibration of capacitance and neutron soil water sensors in a shrinking-swelling clay soil.” Vadose Zone J.VZJAAB, 3(4), 1390–1399.
Fares, A., and Polyakov, V. (2006). “Advances in crop water management using capacitive water sensors.” Adv. Agron.ADAGA7, 90, 43–77.
Gaudo, J. C., et al. (1993). “Soil moisture measurement using a capacitive probe.” AgronomieAGRNDZ, 13, 57–73.
Gear, R. D., Dransfield, A. S., and Campbell, M. D. (1977). “Irrigation scheduling with neutron probe.” J. Irrig. Drain Eng.JRCEA4, 103(3), 291–298.
Geesing, D., Bachmaier, M., and Schmidhalter, U. (2004). “Field calibration of a capacitance soil water probe in heterogeneous fields.” Aust. J. Soil Res.ASORAB, 42(3), 289–299.
Gensler, D., Oad, R., and Kinzli, K. (2009). “Irrigation system modernization: A case study of the Middle Rio Grande Valley.” J. Irrig. Drain. Eng.JIDEDH, 135(2), 169–176.
Grigg, N. (1996). Water resources management: Principles, regulations and cases, McGraw Hill, New York.
Hanson, B. R., Orloff, S., and Peters, D. (2000). “Monitoring soil moisture to help refine irrigation management.” Calif. Agric.CAGRA3, 54(3), 38–42.
Inoue, M., Ould Ahmed, B. A., Saito, T., Irshad, M., and Uzoma, K. C. (2008). “Comparison of three dielectric moisture sensors for measurement of water in saline sandy soils.” Soil Use Manage.SUMAEU, 24(2), 156–162.
Kaleita, A. L., Heitman, J. L., and Logsdon, S. D. (2005). “Field calibration of the theta probe for Des Moines lobe soils”. Appl. Eng. Agric., 21(5), 865–870.
Kelleners, T. J., Robins, D. A., Shouse, P. J., Ayars, J. E., and Skaggs, T. H. (2005). “Frequency dependence of the complex permittivity and its impact on dielectric sensor calibration in soils.” Soil Sci. Soc. Am. J.SSSJD4, 69(1), 67–76.
Kelleners, T. J., Soppe, Ayars, J. E., and Skaggs, T. H. (2004). “Calibration of capacitance probe sensors in a saline silty clay soil.” Soil Sci. Soc. Am. J.SSSJD4, 68(3), 770–778.
Kinzli, K.-D. (2010). “Improving irrigation system performance through scheduled water delivery in the Middle Rio Grande conservancy district.” Ph.D. dissertation, Colorado State Univ., Fort Collins, CO.
Kizito, F., et al. (2008). “Frequency, electrical conductivity and temperature analysis of a low-cost capacitance soil moisture sensor.” J. Hydrol. (Amsterdam)JHYDA7, 352(3–4), 367–378.
Krüger, E., Schmidt, G., and Bruckner, U. (1999). “Scheduling strawberry irrigation based upon tensiometer measurement and a climatic water balance model.” Sci. Hortic.SHRTAH, 81(4), 409–424.
Leib, B. G., Jabro, J. D., and Matthews, G. R. (2003). “Field evaluation and performance comparison of soil moisture sensors.” Soil Sci.SOSCAK, 168(6), 396–404.
Luedeling, E., Nagieb, M., Wichern, F., Brandt, M., Deurer, M., and Buerkert, A. (2005). “Drainage, salt leaching and physico-chemical properties of irrigated man-made terrace soils in a mountain oasis of northern Oman.” GeodermaGEDMAB, 125(3–4), 273–285.
Malicki, M. A., Plagge, R., and Roth, C. H. (1996). “Improving the calibration of dielectric TDR soil moisture determination taking into account the solid soil.” Eur. J. Soil Sci., 47(3), 357–366.ESOSES
McFall, R. L. (1978). “Discussion of ‘Irrigation scheduling with neutron probe’ by Roy D. Gear.” J. Irrig. Drain. Eng.JIDEDH, 104(2), 245.
Mitsuishi, S., and Mizoguchi, M. (2007). “Effects of dry bulk density and soil type on soil moisture measurements using ECH2O-TE probe.” ASA-CSSA-SSSA Int. Annual Meeting, American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, Madison, WI.
Morgan, K. T., Parsons, L. R., Wheaton, T. A., Pitts, D. J., and Obreza, T. A. (1999). “Field calibration of a capacitance water content probe in fine sand soils.” Soil Sci. Soc. Am. J.SSSJD4, 63(4), 987–989.
Mwale, S. S., Azam-Ali, S. N., and Sparkes, D. L. (2005). “Can the PR1 replace the neutron probe for routine soil-water measurement?” Soil Use Manage., 21(3), 340–347.
Nemali, K. S., Montesano, F., Dove, S. K., and van Iersel, M. W. (2007). “Calibration and performance of moisture sensors in soilless substrates: ECH2O and theta probes.” Sci. Hortic.SHRTAH, 112(2), 227–234.
Norikane, J. H., Prenger, J. J., Rouzan-Wheeldon, D. T., and Levine, H. G. (2005). “A comparison of soil moisture sensors for space flight applications.” Appl. Eng. Agric., 21(2), 211–216.
Oad, R., Garcia, L., Kinzli, K.-D., Patterson, D, and Shafike, N. (2009). “Decision support systems for efficient irrigation in the Middle Rio Grande Valley.” J. Irrig. Drain. Eng.JIDEDH, 135(2), 177.
Oad, R., and Kullman, R. (2006). “Managing irrigated agriculture for better river ecosystems—A case study of the Middle Rio Grande.” J. Irrig. Drain. Eng.JIDEDH, 132(6), 579–586.
Paige, G. B., and Keefer, T. O. (2008). “Comparison of field performance of multiple soil moisture sensors in a semi-arid rangeland.” J. Am. Water Resour. Assoc.JWRAF5, 44(1), 121–135.
Paltineanu, I. C., and Starr, J. L. (1997). “Real time soil water dynamics using multi-sensor capacitance probes: Laboratory calibration.” Soil Sci. Soc. Am. J.SSSJD4, 61(6), 1576–1585.
Plauborg, F., Iversen, B. V., and Learke, P. E. (2005). “In situ comparison of three dielectric soil moisture sensors in drip irrigated sandy soils.” Vadose Zone J., 4(4), 1037–1047.VZJAAB
Polyakov, V., Fares, A., and Ryder, M. H. (2005). “Calibration of a capacitance system for measuring water content of tropical soil.” Vadose Zone J.VZJAAB, 4(4), 1004–1010.
Regalado, C. M., Ritter, A., and Rodrıguez, G. R.M. (2007). “Performance of the commercial WET capacitance sensor as compared with time domain reflectometry in volcanic soils.” Vadose Zone J., 6(2), 244–254.VZJAAB
Riley, T. C., Endreny, T. A., and Halfman, J. D. (2006). “Monitoring soil moisture and water table height with a low-cost data logger.” Comput. Geosci., 32(1), 135–140.
Saito, T., Fujimaki, H., and Inoue, M. (2008). “Calibration and simultaneous monitoring of soil water content and salinity with capacitance and four-electrode probes.” Am. J. Environ. Sci., 4(6), 690–699.AJESC5
Sakaki, T., Limsuwat, A., Smits, K. M., and Illangasekare, T. H. (2008). “Empirical two-point α-mixing model for calibrating the ECH2O EC-5 soil moisture sensor in sands.” Water Resour. Res., 44, 1–8.WRERAQ
Seyfried, M. S., and Murdock, M. D. (2004). “Measurement of soil water content with a 50-MHz soil dielectric sensor.” Soil Sci. Soc. Am. J.SSSJD4, 68(2), 394–403.
Shirokova, Y., Forkutsa, I., and Sharafutdinova, N. (2000). “Use of electrical conductivity instead of soluble salts for soil salinity monitoring in Central Asia.” Irrig. Drain. Syst.IDRSEG, 14(3), 199–205.
Smajstrla, A. G., and Locascio, S. J. (1996). “Tensiometer controlled drip irrigation scheduling of tomato.” Appl. Eng. Agric., 12(3), 315–319.
Starr, J. L., and Palineanu, I. C. (2002). “Methods for measurement of soil water content: Capacitance devices.” Methods of soil analysis: Part 4 physical methods, Dane, J. H. and Topp, G. C., eds., Soil Science Society of America, Madison, WI, 463–474.
Topp, G. C., Zegelin, S., and White, I. (2000). “Impact of real and imaginary components of relatively permittivity on time domain reflectometry measurement in soils.” Soil Sci. Soc. Am. J.SSSJD4, 64, 1244–1252.
Veldkamp, E., and O’Brien, J. J. (2000). “Calibration of a frequency-domain reflectometry sensor for humid tropical soils of volcanic origin.” Soil Sci. Soc. Am. J.SSSJD4, 64(5), 1549–1553.
Walker, J. P., Willgoose, G. R., and Kalma, J. D. (2004). “In situ measurement of soil moisture: A comparison of techniques.” J. Hydrol. (Amsterdam)JHYDA7, 293(1), 85–99.
Wraith, J. M., and Or, D. (1999). “Temperature effects on soil bulk dielectric permittivity measured by time domain reflectometry: Experimental evidence and hypothesis development.” Water Resour. Res.WRERAQ, 35(2), 361–369.
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Published In
Journal of Irrigation and Drainage Engineering
Volume 138 • Issue 4 • April 2012
Pages: 310 - 321
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Jan 10, 2011
Accepted: Aug 31, 2011
Published online: Aug 31, 2011
Published in print: Apr 1, 2012
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