Deputy Director of the joint research unit “Géoscience Environnement Toulouse”

Address: 14 avenue Edouard Belin, 31400 Toulouse, FRANCE

Phone: +33 (0)5 61 33 26 64 / +33 (0) 7 71 35 97 41

Email: olivier.ribolzi|DONTWANTSPAM|@ird.fr

Main fields of research and expertise

Olivier Ribolzi, PhD and HDR in hydro-geochemsitry, gained over 20 years of experience in conducting and coordinating interdisciplinary research in IRD, mainly in Southeast Asia, West Africa and the Mediterranean region. His main research interests include the effect of land use / land use change on the hydro-biogeochemical response of headwater catchments, soil erosion and sediment yield, groundwater-stream water interactions, and the occurrence/spread of contaminants. His publishing credits (h-index WoS = 21) include more than 60 articles in refereed journals.

Selected publications

Duvert, C., Butman, D.E., Marx, A; Ribolzi, R., 2018. Preferential subsurface inflows to streams are major hotspots of riverine CO2 evasion. Nat. Geosci. https://doi.org//doi.org/10.1038/s41561-018-0245-y

Deshmukh, C., Guérin, F., Vongkhamsao, A., Pighini, S., Oudone, P., Sopraseuth, S., Godon, A., Rode, W., Guédant, P., Oliva, P., Audry, S., Zouiten, C., Galy-lacaux, C., Robain, H., Ribolzi, O., Kansal, A., Chanudet, V., Descloux, S., Serça, D., 2018. Carbon dioxide emissions from the flat bottom and shallow Nam Theun 2 Reservoir : drawdown area as a neglected pathway to the atmosphere. Biogeosciences 15, 1775–1794. https://doi.org/https://doi.org/10.5194/bg-15-1775-2018

Patin J., E. Mouche, O. Ribolzi, O. Sengtahevanghoung, K.O. Latsachak, B. Soulileuth, V. Chaplot, C.V., 2018. Effect of land use on interrill erosion in a montane catchment of Northern Laos : an analysis based on a pluri-annual runoff and soil loss database. J. Hydrol. https://doi.org/10.1016/j.jhydrol.2018.05.044

Kim, M., Boithias, L., Cho, K. H., Sengtaheuanghoung, O., Ribolzi, O., 2018. Modeling the impact of land use change on basin-scale transfer of fecal indicator bacteria: SWAT model performance. J. Environ. Qual.

Le, Huong; Rochelle-Newall, Emma; Auda, Yves; Ribolzi, O.S., Oloth; Thébault, Elisa ; Soulileuth, Bounsamay; Pommier, T., 2018. Vicinal land use change strongly drives stream bacterial community in a tropical montane catchment. FEMS Microbiol. Ecol. https://doi.org/10.1093/femsec/fiy155

Anneke de Rouw, Olivier Ribolzi, Mathilde Douillet, Hatsadong Tjantahosong, B.S., 2018. Weed seed dispersal via runoff water and eroded soil. Agric. Ecosyst. Environ.

Zimmermann, R.E., Ribolzi, O., Pierret, A., Rattanavong, S., Robinson, M.T., Newton, P.N., Davong, V., Auda, Y., Zopfi, J., Dance, D.A.B., 2018. Rivers as carriers and potential sentinels for Burkholderia pseudomallei in Laos. Sci. Rep. 1–7. https://doi.org/10.1038/s41598-018-26684-y

Gaillardet, J., I. Braud, F. Hankard, S. Anquetin, O. Bour, N. Dorfliger, et al. 2018. OZCAR: The French network of critical zone observatories. Vadose Zone J. 17:180067. doi:10.2136/vzj2018.04.0067

Ribolzi, O., Lacombe, G., Pierret, A., Robain, H., Sounyafong, P., de Rouw, A., Soulileuth, B., Mouche, E., Huon, S., Silvera, N., Latxachak, K.O., Sengtaheuanghoung, O., Valentin, C., 2018. Interacting land use and soil surface dynamics control groundwater outflow in a montane catchment of the lower Mekong basin. Agric. Ecosyst. Environ. https://doi.org/10.1016/j.agee.2018.09.005

Mügler, C., Ribolzi, O., Janeau, J.-L., Rochelle-Newall, E., Latsachack, K., Thammahacksa, C., Viguier, M., Jardé, E., Henri-Des-Tureaux, T., Sengtaheuanghoung, O., Valentin, C., 2019. Experimental and modelling evidence of short-term effect of raindrop impact on hydraulic conductivity and overland flow intensity. J. Hydrol. 570, 401–410. https://doi.org/doi.org/10.1016/j.jhydrol.2018.12.046

Huong T. Le, Emma Rochelle-Newall, Olivier Ribolzi, Jean Louis Janeau, Sylvain Huon, Keooudone Latsachack, T.P., 2020. Land use strongly influences soil organic carbon and bacterial community export in runoff in tropical uplands. L. Degrad. Dev. 31:118–1. https://doi.org/10.1002/ldr.3433

Le, A.H., Gratiot, N., Santini, W., Ribolzi, O., Tran, D., Meriaux, X., Deleersnijder, E., Soares Frazao, S., 2020. Suspended sediment properties in the Lower Mekong River, from fluvial to estuarine environments. Estuar. Coast. Shelf Sci. https://doi.org/10.1016/j.ecss.2019.106522

Lacombe, G., Valentin, C., Sounyafong, P., Rouw, A. De, Soulileuth, B., Silvera, N., Pierret, A., Sengtaheuanghoung, O., Ribolzi, O., 2018. Linking crop structure , throughfall , soil surface conditions, runoff and soil detachment : 10 land uses analyzed in Northern Laos. Sci. Total Environ., 616–617, 1330–1338. https://doi.org/10.1016/j.scitotenv.2017.10.185

Kim, M., Boithias, L., Cho, K. H., Silvera, N., Thammahacksa, C., Latsachack, K., … Ribolzi, O., 2017. Hydrological modeling of Fecal Indicator Bacteria in a tropical mountain catchment. Water Research, 119, 102–113. https://doi.org/10.1016/j.watres.2017.04.038

Wubda, M., M. Descloitres, N. Yalo, O. Ribolzi, J. M. Vouillamoz, M. Boukari, B. Hector, and L. Séguis, 2017. Time-lapse electrical surveys to locate infiltration zones in weathered hard rock tropical areas, J. Appl. Geophys., vol. 142, pp. 23–37, 2017.

Huon, S., O. Evrard, E. Gourdin, I. Lefèvre, J. Reyss, T. Henry, S. Ayrault, and O. Ribolzi, 2017. Suspended sediment source and propagation during monsoon events across nested sub-catchments with contrasted land uses in Laos, J. Hydrol. Reg. Stud., vol. 9, pp. 69–84, 2017.

Manivanh, L, A. Pierret, S. Rattanavong, O. Kounnavongsa, Y. Buisson, I. Elliott, J. -L. Maeght, K. Xayyathip, J. Silisouk, M. Vongsouvath, R. Phetsouvanh, P. N. Newton, G. Lacombe, O. Ribolzi, E. Rochelle-Newall & D. A. B. Dance, 2017. Burkholderia Pseudomallei in a Lowland Rice Paddy: Seasonal Changes and Influence of Soil Depth and Physico-Chemical Properties. Scientific Reports, 1–11. doi:10.1038/s41598-017-02946-z.

Ribolzi, O., Evrard, O., Huon, S., Rouw, A. De, Silvera, N., Latsachack, O., Soulileuth, B., Lefèvre, I., Pierret, A., 2017. From shifting cultivation to teak plantation : effect on overland flow and sediment yield in a montane tropical catchment. Scientific Reports, 1–12. https://doi.org/10.1038/s41598-017-04385-2

Ligaray, M., M. Kim, S. Baek, J. Ra, J. A. Chun, Y. Park, L. Boithias, O. Ribolzi, K. Chon, and K. H. Cho, 2017. Modeling the Fate and Transport of Malathion in the Pagsanjan-Lumban Basin, Philippines. Water, 9, 451.

Boithias, L., Choisy, M., Souliyaseng, N., Jourdren, M., Quet, F., Buisson, Y., Thammahacksa, C., Silvera, N., Latsachack, K., Sengtaheuanghoung, O., Pierret, A., Rochelle-Newall, E., Becerra, S., Ribolzi, O., 2016. Hydrological Regime and Water Shortage as Drivers of the Seasonal Incidence of Diarrheal Diseases in a Tropical Montane Environment. PLoS Negl. Trop. Dis. 10, e0005195. doi:10.1371/journal.pntd.0005195

Evrard, O., Laceby, J.P., Huon, S., Lefèvre, I., Sengtaheuanghoung, O., Ribolzi, O., 2016. Combining multiple fallout radionuclides (137Cs, 7Be, 210Pbxs) to investigate temporal sediment source dynamics in tropical, ephemeral riverine systems. J. Soils Sediments 1–15. doi:10.1007/s11368-015-1316-y

Lacombe, G., Ribolzi, O., de Rouw, A., Pierret, A., Latsachak, K., Silvera, N., Pham Dinh, R., Orange, D., Janeau, J.-L., Soulileuth, B., Robain, H., Taccoen, A., Sengphaathith, P., Mouche, E., Sengtaheuanghoung, O., Tran Duc, T., Valentin, C., 2016. Afforestation by natural regeneration or by tree planting: examples of opposite hydrological impacts evidenced by long-term field monitoring in the humid tropics. Hydrol. Earth Syst. Sci. 12, 12615–12648. doi:10.5194/hessd-12-12615-2015.

Nguyen, H.T.M., Billen, G., Garnier, J., Rochelle-Newall, E., Ribolzi, O., Le, Q.T.P., 2016. Modeling of Faecal Indicator Bacteria (FIB) in the Red River basin (Vietnam ). J. Asian Earth Sci. 1–34. doi:10.1007/s10661-016-5528-4

Ribolzi, O., Rochelle-Newall, E., Dittrich, S., Auda, Y., Newton, P.N., Rattanavong, S., Knappik, M., Soulileuth, B., Sengtaheuanghoung, O., Dance, D.A.B., Pierret, A., 2016. Land use and soil type determine the presence of the pathogen Burkholderia pseudomallei in tropical rivers. Environ. Sci. Pollut. Res. 1–12. doi:10.1007/s11356-015-5943-z

Ribolzi, O., Evrard, O., Huon, S., Rochelle-Newall, E., Henri-des-Tureaux, T., Silvera, N., Thammahacksac, C., Sengtaheuanghoung, O., 2016. Use of fallout radionuclides (7Be, 210Pb) to estimate resuspension of Escherichia coli from streambed sediments during floods in a tropical montane catchment. Environ. Sci. Pollut. Res. 23, 3427–3435. doi:10.1007/s11356-015-5595-z

Rochelle-Newall E.J., Ribolzi O., Viguier M., Thammahacksa C., Silvera N., Latsachack K., Dinh R.P., Naporn P., Sy H.T., Soulileuth B., Hmaimum N., Sisouvanh P., Robain H., Janeau J.L., Valentin C., Boithias L., P.A., 2016. Effect of land use and hydrological processes on Escherichia coli loads in streams of tropical, humid headwater catchments. Sci. Rep. 21, 1–12. doi:10.1038/srep32974

Saqalli, M., Jourdren, M., Maestripieri, N., Guillerme, S., Maire, E., Soulileuth, B., Latsachach, K., Sounyafong, P., Tammahuxsa, L., Sengtaheuanghoung, O., Ribolzi, O., Becerra, S., 2015. Backward waters, modern waters: Perception-Based Regional Mapping territory uses and water-related sanitary stakes in Luang Phabang area (Lao PDR). Appl. Geogr. 60, 184–193. doi:10.1016/j.apgeog.2015.04.001

Rochelle-Newall, E., Nguyen, T.M.H., Le, T.P.Q., Sengtaheuanghoung, O., Ribolzi, O., 2015. A short review of fecal indicator bacteria in tropical aquatic ecosystems: knowledge gaps and future directions. Front. Microbiol. 6, 1–15. doi:10.3389/fmicb.2015.00308

Knappik, M., Dance, D. a. B., Rattanavong, S., Pierret, A., Ribolzi, O., Davong, V., Silisouk, J., Vongsouvath, M., Newton, P.N., Dittrich, S., 2015. Evaluation of Molecular Methods To Improve the Detection of Burkholderia pseudomallei in Soil and Water Samples from Laos. Appl. Environ. Microbiol. 81, 3722–3727. doi:10.1128/AEM.04204-14

Maïga-Yaleu, S.B., Chivenge, P., Yacouba, H., Guiguemde, I., Karambiri, H., Ribolzi, O., Bary, a., Chaplot, V., 2015. Impact of sheet erosion mechanisms on organic carbon losses from crusted soils in the Sahel. Catena 126, 60–67. doi:10.1016/j.catena.2014.11.001

Causse, J., Billen, G., Garnier, J., Henri-des-Tureaux, T., Olasa, X., Thammahacksa, C., Latsachak, K.O., Soulileuth, B., Sengtaheuanghoung, O., Rochelle-Newall, E., Ribolzi, O., 2015. Field and modelling studies of Escherichia coli loads in tropical streams of montane agro-ecosystems. J. Hydro-environment Res. 9, 496–507. doi:10.1016/j.jher.2015.03.003

Gourdin, E., Huon, S., Evrard, O., Ribolzi, O., Bariac, T., Sengtaheuanghoung, O., Ayrault, S., 2015. Sources and export of particle-borne organic matter during a monsoon flood in a catchment of northern Laos. Biogeosciences Discuss. 11, 9341–9378. doi:10.5194/bgd-11-9341-2014

Chaplot, V., Ribolzi, O., 2014. Hydrograph separation to improve understanding of dissolved organic carbon dynamics in headwater catchments. Hydrol. Process. 28(21), 5354-5366. doi:10.1002/hyp

Gourdin, E., Evrard, O., Huon, S., Reyss, J.L., Ribolzi, O., Bariac, T., Sengtaheuanghoung, O., Ayrault, S., 2014. Spatial and temporal variability of 7Be and 210Pb wet deposition during four successive monsoon storms in a catchment of northern Laos. J. Environ. Radioact. 136, 195–205. doi:10.1016/j.jenvrad.2014.06.008

Gourdin, E., Evrard, O., Huon, S., Lefèvre, I., Ribolzi, O., Reyss, J.-L., Sengtaheuanghoung, O., Ayrault, S., 2014. Suspended sediment dynamics in a Southeast Asian mountainous catchment: Combining river monitoring and fallout radionuclide tracers. J. Hydrol. 519, 1811–1823. doi:10.1016/j.jhydrol.2014.09.056

Mouche, E., Moussu, F., Mugler, C., Ribolzi, O., Valentin, C., Sengtaheuanghoung, O., Lacombe, G., 2014. Impact of land-use change on the hydrology of North Lao PDR watersheds. IAHS publication, 363: 84-89.

Valentin, C., Boonsaner, A., Janeau, J. L., Jouquet, P., Henry des Tureaux, T., Huon, S., Latsachack, K., Le Troquer, Y., Maeght, J.L., Orange, D., Pham Dinh Rinh, Pierret, A., Podwojewski, P., Ribolzi, O., de Rouw, A., Sengtaheuanghoung, O., Silvera, N., Robain, H., Soulileuth, B., Thothong, W., Tran Duc, Toan, Tran Sy Hai, 2014. Lessons from long-term monitoring of soil erosion in three southeast Asian agricultural catchments undergoing rapid land-use changes. IAHS publication. 363: 303-308.