Skip to Main content Skip to Navigation
Theses

Décomposition de résidus de culture et de matériaux biosourcés : impact sur les communautés microbiennes des sols agricoles et les fonctions associées

Abstract : Waste management is a major problem worldwide. In agriculture, the return of crop residues to the soil is a common practice and represents an interesting opportunity to maintain soil fertility and / or to store carbon. The decomposition of plant materials in soils is influenced by several factors (such as microbial composition, plant material’s nature and quality), and soil microorganisms are its main actors. Moreover, other ways of valorization of non-harvested plant materials are possible, such as their transformation for non-food applications. In the building industry, the interest in using biobased materials (for thermal insulation) is growing and encouraged by the public authorities in construction or renovation projects. However, to our knowledge, the issue of management of these materials end-of-life is not yet addressed, after deconstructing the buildings. In order to better understand different crop residues (wheat straw, rapeseed straw and sunflower stems) decomposition in agricultural soils, we have combined different biochemical / physicochemical characterizations such as biochemical fractionation, thermogravimetric analysis and infrared spectroscopy, with microbial dynamics monitoring (abundance, diversity, function), supplemented by carbon and nitrogen mineralization measures during 3 months incubation in microcosms. Crop residues mineralization is mainly governed by initially different microbiodiversities (derived from permanent grassland or conventional cropping system), and to a lesser extent by their biochemical quality. However, microbial dynamics are influenced by both, types of soils and nature of inputs. As for the sunflower stem coproducts (pith and bark), C mineralization is mainly dictated by their initial quality. Concerning the manufacturing process of a sunflower pith biobased material, it seems to favor its mineralization in soil. The return of this type of material to soil could thus constitute an interesting means of managing its end-of-life.
Document type :
Theses
Complete list of metadatas

Cited literature [283 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02420629
Contributor : Abes Star :  Contact
Submitted on : Friday, December 20, 2019 - 9:34:07 AM
Last modification on : Saturday, December 21, 2019 - 6:37:44 AM
Long-term archiving on: : Saturday, March 21, 2020 - 1:24:30 PM

File

fidamrad2.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02420629, version 1

Citation

Fida Mrad. Décomposition de résidus de culture et de matériaux biosourcés : impact sur les communautés microbiennes des sols agricoles et les fonctions associées. Sciences agricoles. Normandie Université, 2018. Français. ⟨NNT : 2018NORMR109⟩. ⟨tel-02420629⟩

Share

Metrics

Record views

101

Files downloads

317