Saturated Hydraulic Conductivity Variation in Cultivated and Virgin Soils

Variation of saturated hydraulic conductivity (Ks) values of soils under diverse management practices may be needed to determine the required sample number, sample size, and chose suitable sample scheme for characterize the Ks values used in water flow and solute transport modelling studies. The purpose of this study was to examine the variability in Ks and try to understand some part of the determinism of this variability in virgin and adjacent cultivated field using 36 undisturbed soil samples from each location with 0.5-m grid space. Ks was measured with 100 cm3 undisturbed soil cores in laboratory using falling or constant head methods. The results showed that variability of ln (Ks) values (variance = 10.3) at the cultivated site was 2.5 times greater than that (variance = 2.5) at the virgin site. Furthermore, significant Ks differences exist between cultivated sample locations and within the rows of each cultivated location. Greater variations occurred in two cultivated locations may be attributed to compaction by traffic and soil tillage resulting in heterogeneous bulk density over the study area.

Saturated Hydraulic Conductivity Variation in Cultivated and Virgin Soils

Variation of saturated hydraulic conductivity (Ks) values of soils under diverse management practices may be needed to determine the required sample number, sample size, and chose suitable sample scheme for characterize the Ks values used in water flow and solute transport modelling studies. The purpose of this study was to examine the variability in Ks and try to understand some part of the determinism of this variability in virgin and adjacent cultivated field using 36 undisturbed soil samples from each location with 0.5-m grid space. Ks was measured with 100 cm3 undisturbed soil cores in laboratory using falling or constant head methods. The results showed that variability of ln (Ks) values (variance = 10.3) at the cultivated site was 2.5 times greater than that (variance = 2.5) at the virgin site. Furthermore, significant Ks differences exist between cultivated sample locations and within the rows of each cultivated location. Greater variations occurred in two cultivated locations may be attributed to compaction by traffic and soil tillage resulting in heterogeneous bulk density over the study area.

___

  • Albrecht, K.A., S.D. Logsdon, J.C. Parker and J.C. Baker. 1985. Spatial variability of hydraulic properties in the Emporia series. Soil Sci. Soc. Am. J. 49: 1498-1502.
  • Baker, F.G. and J. Bouma. 1976. Variability of hydraulic conductivity in two subsurface horizons of two silt loam soils. Soil Sci. Soc. Am. J. 40: 219-222.
  • Blake, G.R. and K.H. Hartge. 1986. Bulk density. In: Methods of Soil Analysis, Part 1. Physical and Mineralogical Methods. SSSA Book Series: 5 (formerly Agronomy Monograph 9) (Ed. A. Klute). Madison, Wisconsin, USA, pp. 363-375.
  • Bosch, D.D. 1991. Error associated with point observations of matric potential in heterogeneous soil profile. Transactions of the ASAE. 34: 2427-2436.
  • Bouma, J. and F.D. Hole. 1971. Soil structure and hydraulic conductivity of adjacent virgin and cultivated Pedons at two sites: A typic Argiudoll (silt loam) and a typic Eutrochrept (clay). Soil Sci. Soc. Am. J. 35: 316-319.
  • Byers, E. and D.B. Stephens. 1983. Statistical and stochastic analyses of hydraulic conductivity and particle-size in a fluvial sand. Soil Sci. Soc. Am. J. 47: 1072-1081.
  • Cameira, M.R., R.M. Fernando and L.S. Pereira. 2003. Soil macropore dynamics affected by tillage and irrigation for a silty loam alluvial soil in southern Portugal. Soil & Tillage Research. 70: 131-140.
  • Coutadeur, C., Y. Coquet and J. Roger-Estrade. 2002. Variation of hydraulic conductivity in a tilled soil. Europ. J. Soil Sci. 53: 619- 628.
  • D’Agostino, R.B. and M.A. Stephen. 1986. Goodness-of-Fit Techniques. Marcel Dekker Inc. New York, USA.
  • Ersahin, S. 2003. Comparing ordinary kriging and cokriging to estimate infiltration rate. Soil Sci. Soc. Am. J. 67: 1848-1855.
  • Hillel, D. 1982. Introduction to Soil Physics. Academic Press. Inc. San Diego, California, USA.
  • Istok, J.D., D.O. Blout, L. Barker, K.R. Johnejack and D.P. Hammermeister. 1994. Spatial variability in alluvium properties at a low-level nuclear waste site. Soil Sci. Soc. Am. J. 58: 1040- 1051.
  • Klute, A. and C. Dirksen. 1986. Hydraulic conductivity and diffusivity: Laboratory methods. In: Methods of Soil Analysis, Part 1. Physical and Mineralogical Methods. SSSA Book Series: 5 (formerly Agronomy Monograph 9) (Ed. A. Klute). Madison, Wisconsin, USA, pp. 687-732.
  • Logsdon, S.D. and D.B. Jaynes. 1996. Spatial variability of hydraulic conductivity in a cultivated field at different times. Soil Sci. Soc. Am. J. 60: 703-709.
  • Mallants, D., B.P. Mohanty, A. Vervoort and J. Feyen. 1997. Spatial analysis of saturated hydraulic conductivity in a soil with macropores. Soil Tech. 10: 115-131.
  • Mason, D.D., J.F. Lutz and R.G. Petersen. 1957. Hydraulic conductivity as related to certain soil properties in a number of great soil groups-sampling errors involved. Soil Sci. Soc. Am. Proc. 21: 554-560.
  • Minitab. 1994. Reference Manual Release 10 for Windows, Minitab Inc. State College, Pennsylvania, USA.
  • Mohanty, B.P., R.S. Kanwar and R. Horton. 1991. A robust-resistant approach to interpret spatial behavior of saturated hydraulic conductivity of a glacial till soil under no-tillage system. Water Res. Res. 27: 2979-2992.
  • Mohanty, B.P., R.S. Kanwar and C.J. Everts. 1994. Comparison of saturated hydraulic conductivity measurement methods for a glacial-till soil. Soil Sci. Soc. Am. J. 58: 672-677.
  • Peterson, R.G. and L.D. Calvin. 1986. Sampling. In: Methods of Soil Analysis, Part 1. Physical and Mineralogical Methods. SSSA Book Series: 5 (formerly Agronomy Monograph 9) (Ed. A. Klute). Madison, Wisconsin, USA, pp. 35-51.
  • Rogers, J.S. and C.E. Carter. 1987. Soil core sampling for hydraulic conductivity and bulk density. Soil Sci. Soc. Am. J. 51: 1393- 1394.
  • Ryan, T.A. and B.L. Joiner. 1976. Normal Probability Plots and Tests for Normality, Technical report, Statistics Department, The Pennsylvania State University, USA.
  • Stone, J.A. 1991. Core sampling technique for bulk density and porosity determination on a clay loam soil. Soil Till. Res. 21: 377-383.
  • Warrick, A.Q. and D.R. Nielsen. 1980. Spatial variability of soil physical properties in the field. In: Applications of soil physics (Ed. D. Hillel), Academic Press, Inc. New York, USA. pp. 319-344.
  • Zar, J. H. 1996. Biostatistical Analysis. Prentice Hall, Upper Saddle River, New Jersey, USA.