Modeling the effect of soil meso- and macropores topology on the biodegradation of a soluble carbon substrate. (September 2015)

• Record Type: Journal Article
• Authors: Vogel, Laure E.; Makowski, David; Garnier, Patricia; Vieublé-Gonod, Laure; Coquet, Yves; Raynaud, Xavier; Nunan, Naoise; Chenu, Claire; Falconer, Ruth; Pot, Valérie
• Is Part Of: Advances in water resources. Volume 83(2015)
• Page Start: 123
• Page End: 136
• Publication Date: 2015-09
• Subjects: Biodegradation -- Lattice-Boltzmann method -- Pore-scale heterogeneity -- Spatial distribution -- Substrate diffusion -- Microbial habitats; Hydrology -- Periodicals; Hydrodynamics -- Periodicals; Hydraulic engineering -- Periodicals; 551.48
• DOI: 10.1016/j.advwatres.2015.05.020
• Languages: English
• ISSNs: 0309-1708

Abstract

Highlights: We modeled macropore topology control on soluble C substrate degradation by bacteria. A 3D lattice-Boltzmann model was coupled to a compartmental model for biodegradation. Macropores, water and bacteria distributions were described at submillimeter scale. Physical and biological effects were quantified on a complete factorial design. Abstract: Soil structure and interactions between biotic and abiotic processes are increasingly recognized as important for explaining the large uncertainties in the outputs of macroscopic SOM decomposition models. We present a numerical analysis to assess the role of meso- and macropore topology on the biodegradation of a soluble carbon substrate in variably water saturated and pure diffusion conditions . Our analysis was built as a complete factorial design and used a new 3D pore-scale model, LBioS, that couples a diffusion lattice-Boltzmann model and a compartmental biodegradation model. The scenarios combined contrasted modalities of four factors: meso- and macropore space geometry, water saturation, bacterial distribution and physiology. A global sensitivity analysis of these factors highlighted the role of physical factors in the biodegradation kinetics of our scenarios. Bacteria location explained 28% of the total variance in substrate concentration in all scenarios, while the interactions among location, saturation and geometry explained up to 51% of it.