Mapping topsoil field-saturated hydraulic conductivity from point measurements using different methods

Journal of Hydrology and Hydromechanics

Desprats Jean-François¹  Bouvier Christophe²  Vandervaere Jean-Pierre³  Braud Isabelle⁴  Ayral Pierre-Alain⁵ 

[1] BRGM D3E NRE, 1039 Rue Pinville, 34000Montpellier, France.;Hydrosciences, UMR5569 CNRS, IRD, University of Montpellier, Maison des Sciences de l’Eau, 34095MONTPELLIER, France.;Institut des Géosciences de l’Environnement (IGE), (CNRS, Grenoble-INP, IRD, University of Grenoble-Alpes), UGA, CS40700, F-38058 Grenoble Cedex 9, France.;Irstea, UR HHLY (Hydrology Hydraulics), BP 32108, 69616 Villeurbanne Cedex, France.;LGEI – Institut des Sciences des Risques and UMR ESPACE (UMR7300 CNRS, “Antenne Cévenole”, Université de Nice-Sophia-Antipolis, Université d’Avignon et des Pays de Vaucluse), Ecole des mines d’Alès, 6 avenue de Clavières, 30319 Alès cedex, France.;

关键词: infiltration methods;    topsoil field-saturated hydraulic conductivity;    land cover;    geology;    mapping;   

DOI  :  10.1515/johh-2017-0017

来源: DOAJ

【 摘 要 】

Topsoil field-saturated hydraulic conductivity, Kfs, is a parameter that controls the partition of rainfall between infiltration and runoff and is a key parameter in most distributed hydrological models. There is a mismatch between the scale of local in situ Kfs measurements and the scale at which the parameter is required in models for regional mapping. Therefore methods for extrapolating local Kfs values to larger mapping units are required. The paper explores the feasibility of mapping Kfs in the Cévennes-Vivarais region, in south-east France, using more easily available GIS data concerning geology and land cover. Our analysis makes uses of a data set from infiltration measurements performed in the area and its vicinity for more than ten years. The data set is composed of Kfs derived from infiltration measurements performed using various methods: Guelph permeameters, double ring and single ring infiltrotrometers and tension infiltrometers. The different methods resulted in a large variation in Kfs up to several orders of magnitude. A method is proposed to pool the data from the different infiltration methods to create an equivalent set of Kfs. Statistical tests showed significant differences in Kfs distributions in function of different geological formations and land cover. Thus the mapping of Kfs at regional scale was based on geological formations and land cover. This map was compared to a map based on the Rawls and Brakensiek (RB) pedotransfer function (mainly based on texture) and the two maps showed very different patterns. The RB values did not fit observed equivalent Kfs at the local scale, highlighting that soil texture alone is not a good predictor of Kfs.

【 授权许可】

Unknown