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 ofagricultural and forest activities which involve use of increasingly heavy machines, even when the weather conditions may beunfavourable. The European Union Directive for soil protection in preparation will require for the Member States to zone soilcompaction risk for determining priority areas for soil prevention or soil improvement. In this context, the aim of this study is tobuild a methodology to soil compaction risk at national scale. The susceptibility of soil to compaction increases with the soil watercontent. The soil compaction risks are deduced from frequency of appearance of critical water content which implies systematiccompaction. 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 STICSso that it is adapted to the whole French soils; (3) parameterize the mechanical functioning of French soils. The results are mappedwith the Soil geographical data base of France at 1/1 000 000. The compaction risks are thus estimated for three periods of farmingoperation during winter wheat and maize cultivation: soil conditioning/sowing, nitrogenous fertilising and harvest for present andfuture climates. These three operations are characterized by the applied stress and the climatic conditions. Several criteria definingcompacted 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

Cited literature [74 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00553390
Contributor : ABES STAR :  Contact
Submitted on : Friday, January 7, 2011 - 12:49:08 PM
Last modification on : Monday, May 2, 2022 - 2:16:29 PM
Long-term archiving on: : Friday, April 8, 2011 - 3:11:15 AM

File

marie-pierre.lefebvre_1898.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00553390, version 1

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 agricoles. Université d'Orléans, 2010. Français. ⟨NNT : 2010ORLE2003⟩. ⟨tel-00553390⟩

Share

Metrics

Record views

325

Files downloads

751