Influence de différents facteurs opérationnels sur la structure des communautés microbiennes impliquées dans le processus de digestion anaérobie

Abstract : The anaerobic digestion process leads to the production of biomethane, a versatile renewable energy vector. The dynamics and interactions between specific microbial groups are currently considered as key research subjects towards the improvement of the anaerobic digestion (AD) process. Indeed, deeper knowledge of the ecology of AD, the dynamics of the microbial populations and their structure could provide valuable information regarding unexplained and unpredictable failures or malfunctioning of the anaerobic digestion process. The aim of this work was to characterize the microbial communities involved in the AD process, and to study their responses due to the change of operational parameters such as an increase of the organic loading rate, the reactor type (completely stirred tank reactor vs anaerobic baffled reactor), or the start-up phase of a farm reactor with a shift from psychrophilic to mesophilic temperature range. While we observed the installation of similar microbial populations between replicated reactors under stable conditions, best adapted to biogas production, the microbial communities started to diverge once the operational parameters changed. Indeed, due to deterministic environment, most of bacteria and archaea showed redundant functional adaptation to the changing environmental conditions. However, some dominant bacterial populations were also resistant in terms of presence and abundance to the environmental change. The specific microbial communities established in our studied reactors showed also discrepancies in terms of biogas yields. Furthermore, correlations between the bacterial, archaeal and eukaryotic communities were pointed out, indicating the putative influence of eukaryotes on the anaerobic digestion process and the establishment of the other microbes having crucial functions during the anaerobic biomass digestion. Interestingly, shifts inside the anaerobic microbial community due to the gradual change of operational parameters, were detected prior to any biogas production inhibition, giving the opportunity for the development of potential early microbial indicators for assessing the AD process status and improving the microbial management of anaerobic reactors
Document type :
Theses
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01754584
Contributor : Thèses Ul <>
Submitted on : Friday, March 30, 2018 - 9:53:59 AM
Last modification on : Wednesday, July 25, 2018 - 11:12:58 AM

File

DDOC_T_2015_0292_GOUX.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01754584, version 1

Citation

Xavier Goux. Influence de différents facteurs opérationnels sur la structure des communautés microbiennes impliquées dans le processus de digestion anaérobie. Sciences agricoles. Université de Lorraine, 2015. Français. ⟨NNT : 2015LORR0292⟩. ⟨tel-01754584⟩

Share

Metrics

Record views

60

Files downloads

200