Nature, réactivité et biodégradation des matières organiques associées aux argiles d'un bassin sédimentaire

Abstract : The organic matter of 20 clay samples representative of a sedimentary basin was studied. It appears to be humic substances constituted by fulvie acids (4 to 32 %) and humic acids (2 to 58 %). The results lead to propose a typology of these kaolins. In that way three groups are distinguished relatively to the organic carbon, fulvie and humic acids contents. The humic acids, particularly studied, present condensed and polyaromatic structures. Their total N contents are relatively low.. They are rich in oxygen-containing functional groups (especially carboxylic and phenolic), Moreover, they are easily oxydable during pyrolysis at medium temperature (250°C to 350°C). Under favourable conditions (moisture, temperature, mineraI nu trient inputs), the autochtonous microbial communities grow rapidly by using organic matter associated to the clay as carbon an energy source. Some of the micro-organisms involved appear to he oligotrophic. Depending on the organic matter constituents and for relatively short-time incubations, heterotrophic bacteria are able to mineralize in C02 12 to 25 %of the organic matter. This activity promotes the production of microbial biomass and polysacharidic hydrosoluble compounds. It also leads to the transformation of humic acids essentially by oxidation of polyaromatic structures. The stimulation of heterotrophic micro-organisms promotes the biodegradation and biotransformation of highly recalcitrant organic matter. After the biodegradation of organic matter, the clay thermie properties are still the same but the suspension viscosity seems to he slightly modified and the whiteness, a main quality of the kaolins, is improved.
Complete list of metadatas

Cited literature [91 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01747128
Contributor : Thèses Ul <>
Submitted on : Thursday, January 31, 2019 - 11:00:17 AM
Last modification on : Friday, February 1, 2019 - 1:12:29 AM
Long-term archiving on : Wednesday, May 1, 2019 - 1:31:12 PM

File

SCD_T_1995_0165_GERMAIN.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01747128, version 1

Collections

Citation

Corinne Germain. Nature, réactivité et biodégradation des matières organiques associées aux argiles d'un bassin sédimentaire. Science des sols. Université Henri Poincaré - Nancy 1, 1995. Français. ⟨NNT : 1995NAN10165⟩. ⟨tel-01747128⟩

Share

Metrics

Record views

28

Files downloads

33