Skip to Main content Skip to Navigation
Theses

Spatialisation de modèles de fonctionnement hydromécanique des sols appliquée à la prévision des risques de tassement à l'échelle de la France

Abstract : Soil compaction is one of the major processes of soil degradation in Europe. Compaction is mainly due to the mechanization of agricultural and forest activities which involve use of increasingly heavy machines, even when the weather conditions may be unfavourable. The European Union Directive for soil protection in preparation will require for the Member States to zone soil compaction risk for determining priority areas for soil prevention or soil improvement. In this context, the aim of this study is to build a methodology to soil compaction risk at national scale. The susceptibility of soil to compaction increases with the soil water content. The soil compaction risks are deduced from frequency of appearance of critical water content which implies systematic compaction. Soil water content is estimated with the crop model STICS for 30 years on the whole French soils. Before simulations, we must (1) estimate critical water content as a function of soil and applied stress; (2) parameterize the hydraulic module of STICS so that it is adapted to the whole French soils; (3) parameterize the mechanical functioning of French soils. The results are mapped with the Soil geographical data base of France at 1/l 000 000. The compaction risks are thus estimated for three periods of farming operation during winter wheat and maize cultivation: soil conditioning/sowing, nitrogenous fertilising and harvest for present and future climates. These three operations are characterized by the applied stress and the climatic conditions. Several criteria defining compacted soil and compaction risk were used. Maps of soil compaction risk appeared sensitive to these criteria and also showed that compaction risk is resulting from the interaction of three factors: soil types, climate and farming systems without any dominating. The proposed methodology based on use of hydraulic and mechanical models is well adapted to the estimation of compaction risk for cultivated topsoil. But, mechanical properties for French soils must be characterised more precisely in future to limit uncertainties in the mapping of soil compaction risk.
Document type :
Theses
Complete list of metadata

https://hal.inrae.fr/tel-02821095
Contributor : Migration Prodinra <>
Submitted on : Saturday, June 6, 2020 - 6:51:23 PM
Last modification on : Friday, October 23, 2020 - 4:55:53 PM

File

Thèse de Lefebvre_1
Files produced by the author(s)

Identifiers

  • HAL Id : tel-02821095, version 1
  • PRODINRA : 50504

Collections

Citation

Marie-Pierre Lefebvre. Spatialisation de modèles de fonctionnement hydromécanique des sols appliquée à la prévision des risques de tassement à l'échelle de la France. Sciences de la Terre. Université d'Orléans, 2010. Français. ⟨tel-02821095⟩

Share

Metrics

Record views

450

Files downloads

46