|
|
||||||||
im
nekb
a UMR INRA/INAPG Environment and Arable Crops, Institut National de la Recherche Agronomique/Institut National Agronomique Paris-Grignon, B.P. 01, 78850 Thiverval-Grignon, France
b Dep. of Environmental Sciences, Univ. of California, Riverside, CA 92521
c USDA-ARS, George E. Brown, Jr. Salinity Lab., 450 West Big Springs Road, Riverside, CA 92507
d UMR INRA/INAPG Agronomy, Institut National de la Recherche Agronomique/Institut National Agronomique Paris-Grignon, B.P. 01, 78850 Thiverval-Grignon, France
* Corresponding author (coquet{at}grignon.inra.fr)
Received 7 October 2004.
A field experiment was performed to study the effects of soil structure heterogeneity generated by farming practices (i.e., compaction by wheel traffic, plowing, surface tillage) on plot-scale water flow and solute transport. The experiment involved a 4 by 2 m2 field plot that was uniformly sprinkle irrigated with water and bromide for about 6 h. Independently measured soil hydraulic functions were used to simulate the experiment with a numerical flow and transport model (HYDRUS-2D) using a fully deterministic approach for describing soil heterogeneity. The numerical model reproduced observed flow and transport processes only after adjustments were made to the soil hydraulic functions. Adjustments were needed to account for increased flow and transport into and through the soil between the compacted zones below the wheel tracks, and to predict double concentration peaks caused by the umbrella (or shadow) effects of compacted soil clods. Global optimization of the soil hydraulic parameters produced a satisfactory description of the very heterogeneous flow patterns, with the resulting hydraulic parameters showing only limited correlation among each other. We demonstrate that double-peak concentration profiles can result from the presence of tillage-induced soil heterogeneities.
Abbreviations: TDR, time domain reflectometry
This article has been cited by other articles:
![]() |
J. Vanderborght and H. Vereecken Review of Dispersivities for Transport Modeling in Soils Vadose Zone J., January 24, 2007; 6(1): 29 - 52. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Coquet, C. Coutadeur, C. Labat, P. Vachier, M. Th. van Genuchten, J. Roger-Estrade, and J. Simunek Water and Solute Transport in a Cultivated Silt Loam Soil: 1. Field Observations Vadose Zone J., July 18, 2005; 4(3): 573 - 586. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||