Skip to Main content Skip to Navigation
Theses

Distribution de la drilosphère lombricienne et caractérisation bio-physique des faciès de bioturbation sous gradient de désintensification du travail mécanique des sols

Abstract : This thesis aimed to create and to develop a field methodology to characterize the drilosphere (the sphere of earthworm control) in a variety of agricultural settings. Our study was led in Brittany (France) on the experimental plot that compare agricultural soil constraints (Conventional tillage, Superficial tillage and No tillage) associated with mineral or organic fertilization. The « facies » concept is introduced in this study, to define areas of soil profile that exhibit morphologic features of soil physical processes: anthropogenic, biological and climatic. We built a typology of 11 facies (7 from earthworm activities) validated by a micromorphological approach. Mapping of soil profiles is developed to assess the impact of environmental filters on the spatial extent of earthworm biogenic facies. Furthermore, we studied the chemical properties (C, N) and the structure of bacterial communities (DNA diversity). Tillage appeared to determine the spatial distribution of biogenic facies in the soil profile. In contrast, fertilization which significantly affects the communities of earthworm, does not modify the spatial distribution of biogenic facies. Our results indicate too that pedoclimatic processes are widely involved in the spatial and temporal evolution of the biostructures. DNA analysis confirms the impact of earthworm on soil bacterial communities. Thus, the characterization of facies established the basis of new indicators for assessing the influence of earthworm activities on soil quality.
Complete list of metadata

Cited literature [24 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00456024
Contributor : Valerie Briand <>
Submitted on : Thursday, February 11, 2010 - 3:43:29 PM
Last modification on : Thursday, January 14, 2021 - 11:50:41 AM
Long-term archiving on: : Friday, June 18, 2010 - 8:17:56 PM

Identifiers

  • HAL Id : tel-00456024, version 1

Citation

Denis Piron. Distribution de la drilosphère lombricienne et caractérisation bio-physique des faciès de bioturbation sous gradient de désintensification du travail mécanique des sols. Ecologie, Environnement. Université Rennes 1, 2008. Français. ⟨tel-00456024⟩

Share

Metrics

Record views

1019

Files downloads

1230