HR: 17:20h
AN: H22J-06    [PDF]
TI: Application of the Preisach Model to Soil-moisture Hysteresis
AU: * O'Kane, J
EM: jpokane@ucc.ie
AF: Environment Institute, and Department of Civil and Environmental Engineering, National University of Ireland, Cork, College Road, Cork, 021 Ireland
AU: Pokrovskii, A
EM: a.pokrovskii@ucc.ie
AF: Boole Research Centre in Informatics, and Department of Applied Mathematics, National University of Ireland, Cork, College Road, Cork, 021 Ireland
AU: Krejci, P
EM: krejci@math.cas.cz
AF: Institute of Mathematics, Czech Academy of Sciences, Zitna 25, CZ - 115 67, Prague, 01 Czech Republic
AU: Haverkamp, R
EM: randel.haverkamp@hmg.inpg.fr
AF: Laboratoire d'‚tude des Transferts en Hydrologie et Environnement (CNRS,UJF,INPG,IRD), LTHE BP 53 38 041 GRENOBLE Cedex 09, Grenoble, 09 France
AB: An examination of the physics of the land phase of the hydrological cycle shows that the most important non-linearities occur in the unsaturated zone of the soil. These have been studied using switched boundary conditions applied to the one-dimensional form of Richards differential equation, modelling the wetting and drying of a column of bare or vegetated soil, at a scale of roughly one meter. However, the strongly non-linear hysteretic property of the soil moisture characteristic is usually ignored. Smooth non-linear differential, or integro-differential, operators cannot reproduce soil-moisture hysteresis. The classical Preisach Model is presented and applied to the quantitative description of soil-moisture scanning curves. The Preisach model is a deterministic, rate independent non-linear operator with return-point memory and congruent loops. Special, one parameter, classes of Preisach operators are proposed as models of soil-moisture hysteresis for particular soils. The results of fitting these operators to laboratory and field data, taken from the Grenoble GRIZZLY Soil Database, are presented and discussed.
UR: http://www.bcri.ucc.ie/BCRI_15.pdf
DE: 1875 Unsaturated zone
SC: Hydrology [H]
MN: 2003 Fall Meeting