Upscaling soil hydraulic properties at locall scale through topography

Document Type : Research Paper


1 Tarbiat Modares University

2 Assistant Professor, Soil Conservation and Watershed Management Research Institute (SCWMRI), Tehran, Iran


Estimating effective soil hydraulic properties for largescale is an outstanding challenge in hydrologic modelling. The aim of this study was to provide effective van Genuchten-Mualem hydraulic parameters at localscale through topography-based Upscaling Pedotransfer functions (PTFs) and spectrotransfer functions (STFs, SPTFs). The Zanjanrood sub-watershed with an area about 250 Km2 was selected as the study area for this research.hereby, a topography-based aggregation scheme, the so-called power average operator, PAO, was used to upscale (1Km×1Km) point scale parameters of , , and . With respect to the results, considerable and significant correlations (R>0.50) were obtained between measured and estimated hydraulic parameters. Upscaled STFs showed the largest and significant correlations with upscaled measurements of (0.65), (0.70), (0.86), while upscaled PTFs performed best for (0.55). The PAO performed best in the pixels which have the highest topographic index (CTI). The biggest R values were obtained between shape parameters (i.e., and ) andthe standard deviation CTI as well as between and with the average CTI. The ASAR estimated soil moisture values appeared to be significantly (p<0.005) correlated (-0.453) with the average CTI. The results of this study indicate that the topography is an important factor in characterization ofeffective soil hydraulic properties at localscale.


Main Subjects

Babaeian, E. Homaee, M. and Norouzi, A.A. (2013a). Retrieving surface soil water content using ENVISAT ASAR radar data. Journal of Water research in Agriculture, 27(4), 611-622. (In Farsi)
Babaeian, E. Homaee, M. and Norouzi, A.A. (2013b). Deriving and validating point spectrotransfer functions in Vis-NIR-SWIR range to estimate soil water retention. Journal of Water and Soil Resources Conservation, 3 (2) 27- 41.  (In Farsi)
Babaeian, E. Homaee, M. and Norouzi, A.A. (2014). Deriving and validating parametric spectrotransfer functions forestimatingsoil hydraulic properties in VIS-NIR-SWIR range. Journal of Water and Soil Resources Conservation, 3(3), 21-36. (In Farsi)
Beven, K.J., Kirkby, M. J. Schofield, N. and Tagg,A. F. (1984). Testing a physically-based flood forecasting-model (TOPMODEL) for 3 UK catchments. Journal of Hydrology, 69(1-4), 119–143.
Das, N.N. Mohanty, B.P. and Njoku, E.G. (2008). A Markov chain Monte Carlo algorithm for upscaled SVAT modeling to evaluate sattelite-based soil moisture measurements.Water Resources Research. 44: W05416. [doi: 10.1029/ 2007WR006472].
Famiglietti, J.S. Rudnicki, J. W. and Rodell, M. (1998). Variability in surface moisture content along a hillslope transect: Rattlesnake Hill, Texas, Journal of Hydrology, 210, 259–281, doi:10.1016/S0022-1694(98)00187-5.
Gee, G.W. and Bauder, J.W. (1986). Particle size analysis. In: Klute, A. (Ed.), Methods of Soil Analysis: Part I. Second edition. Agronomy Monograph, vol. 9. ASA and SSSA, Madison, WI, p. 383–411.
Hawley, M.E. Jackson, T. J. and McCuen, R. H. (1983). Surface soil- moisture variation on small agricultural watersheds, Journal of Hydrology, 62, 179–200, doi:10.1016/0022-1694(83)90102-6.
Hillel, D. (1991). Introduction to Soil Physics, Academic Press, San Diego, Cal.
Jana, R.B. and Mohanty, B. (2012c). A comparative study of multiple approaches to soil hydraulic parameter scaling applied at the hillslope scale. Water Resources Research, 48,W02520.
Jana, R.B. and Mohanty, B. (2012b). A topography-based scaling algorithm for soil hydraulic parameters at hillslope scales: Field testing. Water Resources Research, 48,W02519.
Jana, R.B. and Mohanty, B. (2012a). On topographic controls of soil hudraulic parameter scaling at hillslope scales. Water Resources Research, 48,W02518.
Kirkby, M. J. (1975). Hydrograph modeling strategies, in Process in Physical and Human Geography, edited by R. Peel, M. Chisholm, and P. Haggett, pp. 69–90, Heinemann, London.
Kohnke, H., and Franzmeier, D. P. (1995). Soil Science Simplified, 4th ed., Waveland, Long Grove, Ill.
Lag, J. (1951), Illustration of influence of topography on depth of A2-layer in Podzol profiles. Soil Science, 71(2), 125–127.
Mohanty, B. P., and Mousli, Z. (2000). Saturated hydraulic conductivity and soil water retention properties across a soil-slope transition, Water Resources Research, 36(11), 3311–3324, doi:10.1029/2000WR900216.
Mualem, Y. (1976). New model for predicting hydraulic conductivity of unsaturated porous media. Water Resources Research, 12, 513–522.
Pradhan, N. R. Tachikawa, Y.and Takara, K. (2006). A downscaling method of topographic index distribution for matching the scales of model application and parameter identification. Hydrological Process, 20(6), 1385–1405, doi:10.1002/Hyp.6098.
Tedrow, J. C. F. (1951). Influence of topography and position on classifica- tion of soils having impeded drainage, Soil Science, 71(6), 429–438.
van Genuchten, M.Th. (1980). A close-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Science Society of America Journal, 44, 892–898.
Vereecken, H. Weynants, M. Javaux, M. Pachepsky, Y. Schaap, M.G. and van Genuchten, M.Th. (2010). Using Pedotransfer Functions to Estimate the van Genuchten–Mualem Soil Hydraulic Properties: A Review. Vadose Zone Journal, 9: 795-820.
Vereecken, H. Huisman, J. A. Bogena, H. Vanderborght, J. Vrugt, J. A. and Hopmans, J. W. (2008). On the value of soil moisture measurements in vadose zone hydrology: A review. Water Resources Research, 44, W00D06, doi:10.1029/2008WR006829.
Vereecken, H., R. Kasteel, J. Vanderborght, and T. Harter (2007), Upscal- ing hydraulic properties and soil water flow processes in heterogeneous soils: A review. Vadose Zone Journal, 6, 1–28.
Walkley, A.J. and Black, I.A. (1934). An examination of Degtjareff method for determining soil organic matter and a proposed modification of the chromic acid titration method. Soil Science, 37: 29–38.
Wen, X.H. and Gomez-Hernandez, J. J. (1996). Upscaling hydraulic conductivities in heterogeneous media: An overview, Journal of Hydrology, 183.
Western, A. W. Zhou,S. L.  Grayson, R. B. McMahon, T. A. Bloschl, G. and Wilson, D. J. (2004). Spatial correlation of soil moisture in small catchments and its relationship to dominant spatial hydrological proc- esses.Journal of Hydrology, 286(1), 113–134.
Wilson, D. J. Western, A. W. and Grayson, R. B. (2004). Identifying and quantifying sources of variability in temporal and spatial soil moisture observations.Water Resources Research, 40(2), W02507, doi:10.1029/2003 WR002306.
Yager, R. R. (2001). The power average operator, IEEE Trans. Syst. Man Cybern. Part A, 31(6), 724–731.