INRA Centre de Bordeaux Aquitaine
71 avenue E. Bourlaux
CS 20032 33882 Villenave d'Ornon cedex
05 57 12 24 84

Frederic.Ouedraogo@inra.fr

Education

2013: Scientific Baccalaureate - Ouagadougou (Burkina Faso)

2016 : Licence Ecology and Environment - Sétif (Algeria)

2018: Master's degree in Environmental Management - Marseille (France).

Since October 2018 : PhD on "Temporal evolution of copper availability in soils under organic agriculture".

Research and/or skills

I did some research internships during my master's degree:

Study of root development using X-ray tomography,
Study of the impact of crops on silicon bioavailability (CEREGE - Aix-en-Provence).
During my course, I had in-depth courses on biogeochemical cycles, waste management and polluted soils. I have also been trained in various laboratory techniques for the characterization of soil particles: laser particle size, X-ray diffraction, spectrometry. I have also worked with software such as R and QGIS.

Project in progress

TEMPORAL EVOLUTION OF COPPER AVAILABILITY IN SOILS UNDER ORGANIC FARMING

Copper has been used as a fungicide for more than 100 years in viticulture, arboriculture and market gardening. It is currently the only fungicide authorized in organic farming. Because of the accumulation of copper in the top soil horizon (Brun et al., 1998), high concentrations are noticed. Phytotoxicities have been observed in vineyard soils in conversion crop farming, particularly in Languedoc-Roussillon (Michaud et al., 2007, Bravin, 2008) and the problems of vineyard dieback may be linked to this contamination. The ecotoxicity of copper depends on its availability, ie its concentration in the soil solution in a free ionic form. Copper has a very strong affinity for organic matter. Thus the amount of soluble organic matter and its complexation properties control the concentration of free ion in solution and therefore the availability of copper in the soil. It was found that the organic matter reactivity toward copper varied depending on the soils (Djaé et al., 2007). The default parameterization of geochemical models was then impossible. However, the link between the reactivity of soluble organic matter, its characterization and the physicochemical properties of the soil is still poorly understood. The supply of fresh raw materials, which mineralize rapidly by inducing a 'priming effect', will lead to modify the chemical composition of the soil solution. In agricultural soils, copper availability would vary over time depending on climatic conditions, inputs of fresh raw materials (green manures, straw, effluents) and the initial level of soil contamination. This thesis aims to understand if the dynamics of organic matter in soils, in connection with the evolution of climatic conditions, control the availability and ecotoxicity of copper. This will allow us to identify the pedoclimatic conditions limiting or exacerbating the availability, in order to limit the soil-plant transfer to decrease phytotoxicity, or exacerbating it to promote phytoextraction. The thesis will therefore study, in greenhouse or open field conditions, the links between soluble organic matter and copper speciation and the consequences on plant uptake. We will test this hypothesis : • on soils with different copper contamination and physicochemical properties, • at different temperatures to modify the mineralization of the solid organic matter, • with intake of fresh organic matter, which stimulates microbial activity, mineralization and priming effect. This study will focus on vineyard or market gardening soils, in organic farming, in which the major contaminant is copper.

Supervised by:

• Laurence DENAIX (UMR ISPA 1391)
• Edith PARLANTI (UMR CNRS 5805 EPOC)

Teachings 

 TP & TD supervision for Bordeaux Sciences Agro master's degrees.