10
E. Yetbarek and R. Ojha
Soil heterogeneity was observed to increase soil moisture while root water uptake
was decreasing it. Root water uptake effect on soil moisture distribution was more
pronounced under homogenous soils than in heterogeneous soils. The soil moisture
variability range depends on the media type, and it decreases with increasing soil
heterogeneity. Soil suction head decreases with increasing soil heterogeneity whether
root water uptake was considered or not. Its response for the applied water depends
on heterogeneity and consideration of root water uptake. Hydraulic conductivity
increases with increasing soil heterogeneity when root water uptake was ignored,
and it depends on the heterogeneity level when root water uptake was accounted.
The depth range where the effects of root water uptake on suction head and hydraulic
conductivity observed depends on the type of medium.
Acknowledgements The research was funded by Science and Engineering Research Board,
Department of Science and Technology, India, under Grant No. ECR/2016/000378.
References
1. Bresler E, Dagan G (1988) Variability of yield of an irrigated crop and its causes 1. Statement
of the problem and methodology. Water Resour Res. 24(3):381–387
2. Green TR, Dunn GH, Erskine RH, Salas JD, Ahuja LR (2009) Fractal analyses of steady
infiltration and terrain on an undulating agricultural field. Vadose Zone J 8(2):310–320
3. Usowicz B, Lipiec J (2017) Spatial variability of soil properties and cereal yield in a cultivated
field on sandy soil. Soil Tillage Res 174:241–250
4. Bevington J, Piragnolo D, Teatini P, Vellidis G, Morari F (2016) On the spatial variability of
soil hydraulic properties in a Holocene coastal farmland. Geoderma 262:294–305. https://doi.
org/10.1016/j.geoderma.2015.08.025
5. Nielsen DR, Biggar W, Erh KT (1973) Spatial variability of field-measured soil-water
properties. Hilgardia 42(7):215–260
6. Sharma ML, Gander GA, Hunt CG (1980) Spatial variability of infiltration in a watershed. J
Hydrol 45:101–122
7. Warrick AW, Nielsen DR (1980) Spatial variability of soil physical properties in the field. In:
Applications of soil physics. Academic Press, Inc., pp 319–344
8. Herbst M, Diekkrüger B, Vereecken H (2006) Geostatistical co-regionalization of soil hydraulic
properties in a micro-scale catchment using terrain attributes. Geoderma 132:206–221
9. Russo D, Zaidel J, Laufer A (1998) Dimensional partially saturated heterogeneous soil. Water
Resour Res 34(6):1451–1468
10. Chen P-Y, Chen C-H, Hsu N-S, Wu C-M, Wen J-C (2012) Influence of heterogeneity on
unsaturated hydraulic properties: (1) local heterogeneity and scale effect Hydrol Process
26(23):3593–3603
11. Ojha CSP, Rai AK (1996) Nonlinear root-water uptake model. J Irrig Drain Eng 122(4):198–202
12. van Genuchten MT, Nielsen DR (1985) On describing and predicting the hydraulic properties
of unsaturated soils. Ann Geophys 3(5):615–628
13. Fiori A, Russo D (2007) Numerical analyses of subsurface flow in a steep hillslope under
rainfall: the role of the spatial heterogeneity of the formation hydraulic properties. Water
Resour Res 43(7):1–14
E. Yetbarek and R. Ojha
Soil heterogeneity was observed to increase soil moisture while root water uptake
was decreasing it. Root water uptake effect on soil moisture distribution was more
pronounced under homogenous soils than in heterogeneous soils. The soil moisture
variability range depends on the media type, and it decreases with increasing soil
heterogeneity. Soil suction head decreases with increasing soil heterogeneity whether
root water uptake was considered or not. Its response for the applied water depends
on heterogeneity and consideration of root water uptake. Hydraulic conductivity
increases with increasing soil heterogeneity when root water uptake was ignored,
and it depends on the heterogeneity level when root water uptake was accounted.
The depth range where the effects of root water uptake on suction head and hydraulic
conductivity observed depends on the type of medium.
Acknowledgements The research was funded by Science and Engineering Research Board,
Department of Science and Technology, India, under Grant No. ECR/2016/000378.
References
1. Bresler E, Dagan G (1988) Variability of yield of an irrigated crop and its causes 1. Statement
of the problem and methodology. Water Resour Res. 24(3):381–387
2. Green TR, Dunn GH, Erskine RH, Salas JD, Ahuja LR (2009) Fractal analyses of steady
infiltration and terrain on an undulating agricultural field. Vadose Zone J 8(2):310–320
3. Usowicz B, Lipiec J (2017) Spatial variability of soil properties and cereal yield in a cultivated
field on sandy soil. Soil Tillage Res 174:241–250
4. Bevington J, Piragnolo D, Teatini P, Vellidis G, Morari F (2016) On the spatial variability of
soil hydraulic properties in a Holocene coastal farmland. Geoderma 262:294–305. https://doi.
org/10.1016/j.geoderma.2015.08.025
5. Nielsen DR, Biggar W, Erh KT (1973) Spatial variability of field-measured soil-water
properties. Hilgardia 42(7):215–260
6. Sharma ML, Gander GA, Hunt CG (1980) Spatial variability of infiltration in a watershed. J
Hydrol 45:101–122
7. Warrick AW, Nielsen DR (1980) Spatial variability of soil physical properties in the field. In:
Applications of soil physics. Academic Press, Inc., pp 319–344
8. Herbst M, Diekkrüger B, Vereecken H (2006) Geostatistical co-regionalization of soil hydraulic
properties in a micro-scale catchment using terrain attributes. Geoderma 132:206–221
9. Russo D, Zaidel J, Laufer A (1998) Dimensional partially saturated heterogeneous soil. Water
Resour Res 34(6):1451–1468
10. Chen P-Y, Chen C-H, Hsu N-S, Wu C-M, Wen J-C (2012) Influence of heterogeneity on
unsaturated hydraulic properties: (1) local heterogeneity and scale effect Hydrol Process
26(23):3593–3603
11. Ojha CSP, Rai AK (1996) Nonlinear root-water uptake model. J Irrig Drain Eng 122(4):198–202
12. van Genuchten MT, Nielsen DR (1985) On describing and predicting the hydraulic properties
of unsaturated soils. Ann Geophys 3(5):615–628
13. Fiori A, Russo D (2007) Numerical analyses of subsurface flow in a steep hillslope under
rainfall: the role of the spatial heterogeneity of the formation hydraulic properties. Water
Resour Res 43(7):1–14