Career

1987-1992 : INRA Technician in Laon, 1992-2007 INRA Assistant Engineer in Laon, 2008-2019 INRA Assistant Engineer in Reims, 2020-2024 INRA Design Engineer in Reims

Education

1983-1985 : DUT in Physical Measurements of Lille

Skills

Elemental analyses, isotope mass spectrometry, gas chromatography, various physicochemical analyses

Research interests

Determinations of total C, total N, 13C and 15N on soil, plant and solution samples, by high-temperature catalytic combustion and mass spectrometry. Maintenance of the analytical tool, planning and execution of analyses for the unit's projects and in external service, data processing (with critical analysis of the quality of the results), assistance to the requesters of analyses for the exploitation of their results, improvement of the analytical tool and quality procedures and, development to meet specific analysis needs.

Participation in the scientific projects of the UMR FARE involving the use of stable isotopes

Main publications

Bertrand I., Delfosse O., Mary, B. (2007) Carbon and nitrogen mineralization in acidic, limed and calcareous agricultural soils: Apparent and actual effects. Soil Biology and Biochemistry 39 276-288. DOI

Coppens F., Alavoine G., Delfosse O., Recous S. (2009) “Evaluation of sample pre-treatment and potential contamination of soluble carbon in soil extracts during lyophilization”  Soil Biology & Biochemistry, 41, 6, 1335-1337 DOI

Prache, S., Kondjoyan, N., Delfosse, O., Chauveau-Duriot, B., Andueza, D., Cornu, A. (2009) Discrimination of pasture-fed lambs from lambs fed dehydrated alfalfa indoors using different compounds measured in the fat, meat and plasma. Animal , 3, 598-605

Delfosse, O. ; Froidmont, E. ; Fernandez Pierna, J.A. ; Martin, C. ; Dehareng, F. (2010) Estimation of methane emissions by dairy cows on the basis of milk composition. [Communication orale (résumé)]. Greenhouse Gases and Animal Agriculture Conference (GGAA2010) ; 2010/10/03-08 ; Banff (CAN). McGeough, E.J. (Editeur) ; McGinn, S.M. (Editeur). Proceedings of the 4th Greenhouse Gases and Animal Agriculture Conference. 2010. 198

Salon, C. ; Voisin, A.S. ; Delfosse, O. ; Mary, B. (2010) Methodologies for measuring symbiotic nitrogen fixation in the field. Munier-Jolain, N. (Coordinateur) ; Biarnès, V. (Coordinateur) ; Chaillet, I. (Coordinateur) ; Lecoeur, J. (Coordinateur) ; Jeuffroy, M.H. (Coordinateur). Physiology of the pea crop. Boca Raton (USA) : CRC Press ; 83-87.

Devincenzi T., Delfosse O., Andueza D., Nabinger C., Prache S. (2013) Dose-dependent response of nitrogen stable isotope ratio to proportion of legumes in diet to authenticate lamb meat produced from legume-rich pastures. Food Chemistry, 152 : 456-461

Attard E., Le Roux X., Charrier X., Delfosse O., Guillaumaud N., Lemaire G. (2016) Delayed and assymmetric responses of soil C pools and N fluxes to grassland/cropland conversions. Soil Biology & Biochemistry, 97, 31-39

Other activities

Animation of the unit's sustainable development group