Profil de Vincent JASSEY
Email : vincent.jasseySPAMFILTER@univ-tlse3.fr
Téléphone / phone: +33 5 61 55 89 23
Bureau / office : 341
Institution : CNRS
Statut / status: Chercheur
Adresse professionnelle / address:EcoLab (UMR 5245 CNRS-UPS-INPT)
Université Toulouse III – Paul Sabatier
Bât. 4R1 / Office 341
118 route de Narbonne
F-31062 Toulouse cedex 09
Site perso / personal website :
01/2017 – current: Researcher at The National Center for Scientific Research (CNRS)- Functional Ecology and Environment laboratory (EcoLab), University of Paul Sabatier III, Toulouse (France)
01/2015 – 12/2016: Post-Doctoral position at the Swiss Federal Institute for Forest, Snow and Landscape (WSL) in the Research Unit Community Ecology (Site Lausanne, ECOS group led by Prof. A. Buttler, Switzerland). SNF grant / SPHAGNOL project. PI: Prof. Luca Bragazza.
04/2012 – 12/2014: Post-Doctoral position at the Swiss Federal Institute for Forest, Snow and Landscape WSL in the Research Unit Community Ecology (Site Lausanne, ECOS group led by Prof. A. Buttler, Switzerland) and Adam Mickiewicz University of Poznan (Poland). Swiss Contribution/Polish-Swiss Research grant; CLIMPEAT project. PI: Prof. Mariusz Lamentowicz.
12/2011 – 03/2012: Post-Doctoral position at Chrono-Environnement Laboratory (Montbéliard, France). Supervised by Prof. Nadine Bernard
10/2011 – 11/2012: Post-Doctoral position at Soil Biology Laboratory (Neuchâtel, Switzerland). Supervised by Prof. Edward Mitchell.
10/2008-11/2011: Ph.D. at Chrono-Environnement Laboratory (Montbéliard, France). Supervised by Prof. Daniel Gilbert, Dr. Geneviève Chiapusio and Dr. Philippe Binet. Awarded with the highest honours.
I am a community ecologist studying trophic interactions. My research aims at understanding the structure and function of ecological networks, and how these networks matter for ecosystem functioning and services. Particularly, I’m interested at understanding the response of ecological networks to climate change, and how these changes play out in ecosystem functioning.
Plant-plant, plant-soil and plant-microbe interactions play a fundamental role in community structure and dynamics and in ecosystem functioning. In my research, I aim at understanding how these interactions modify or improve the functioning of ecosystems. Recently, I focused my research on the role of plant secondary metabolites in driving soil microbial food web structure and functioning. In addition, I am interested in determining the role of plant diversity and cover on soil food web and ecosystem functions such as productivity, decomposition, and nutrient cycling. Finally, I aim to develop more research on trophic interactions within food webs, especially concerning the role of mixotrophic organisms -organisms that mix up their role in food webs as either autotrophs or heterotrophs.
Climate is one of the major drivers of species distributions and interactions in ecosystems. However, climate changes are are expected to shift species distributions or modify their abundance and dominance patterns, generating novel communities composed of new combinations of species. These changes are likely to perturb ecosystem functioning. My research aims at understanding what makes plant and microbial communities resilient to external changes, and what makes them fragile. In my previous work in peatlands, I highlighted the importance of extreme warming events in shifting plant-plant, plant-soil and microbe-microbe interactions. Moreover, I am also interested in exploring the relative importance of the different components of climate change (e.g. warming, flooding, drought etc.) and in showing how these factors together drive ecosystem functions. Ecological communities and species interactions respond to changing climate in different way; some of them unexpectedly break down (losses of species and functions) rapidly while others resist longer to perturbations. I am developing research aiming at understanding the response of ecosystems to climate changes and trying to identify tipping points which could explain the difference in response of communities to extreme climatic events.
2018-2020: French Agency for Research (ANR) - Young researcher grant (ANR-JCJC):
Rethinking the peatland carbon cycle - identifying the role of mixotrophs in the biological carbon pump / Repenser le cycle du carbone des tourbières : identifier le rôle des protistes mixotrophes dans la pompe à carbone biologique - 313k€. Principal Investigator
2015 – 2016: Swiss National Science Foundation project funding grant: Allelochemical arms race in peatlands; the role of polyphenols in aboveground-belowground interactions (Sphagnol) - 220k€. Co-Principal Investigator
Sanginés de Carcer, P., Vitasse, Y., Peñuleas, J., Jassey, V.E.J., Buttler, A., Signarbieux, C. (in press). Vapor-pressure deficit and extreme climatic variables limit tree growth. Global Change Biology, xx, xx-xx.
Robroek, B. J. M.*, Jassey, V. E. J.*, Payne, R. J., Martí, M., Bragazza, L., Bleeker, A., et al. (2017). Taxonomic and functional turnover are decoupled in European peat bogs. Nature Communications, 8, 1161. http://doi.org/10.1038/s41467-017-01350-5
Jassey, V.E.J., Reczuga, M.K., Zielińska, M., Słowińska, S., Robroek, B.J.M., Mariotte, P., Seppey, C.V.W., Lara, E., Barabach, J., Słowiński, M., Bragazza, L., Chojnicki, B. H., Lamentowicz, M., Mitchell, E.A.D., Buttler, A. (in press). Tipping point effect in plant-fungal interactions under severe drought causes abrupt rise in peatland ecosystem respiration. Global Change Biology, xx, xx-xx.
Robroek, J.M., Jassey, V.E.J., Beltman, B., Hefting, M.M., (2017). Diverse fen plant communities enhance carbon-related multifunctionality, but do not mitigate negative effects of drought. Royal Society Open Science, 4, 170449.
Gay-des-Combes, J. M., Sanz Carrillo, C., Robroek, B. J. M., Jassey, V. E. J., Mills, R. T. E., Arif, M. S., et al. (2017). Tropical soils degraded by slash-and-burn cultivation can be recultivated when amended with ashes and compost. Ecology and Evolution, 60 (Part B), 157–11.
Küttim, M., Hofsommer, M. L., Robroek, B. J. M., Signarbieux, C., Jassey, V. E. J., Laine, A., et al. (2017). Freeze-thaw cycles simultaneously decrease peatland photosynthetic carbon uptake and ecosystem respiration. Boreal Environment Research, 22, 267–276.
Geisen, S., Mitchell, E., Wilkinson, D. M., Adl, S., Bonkowski, M., Brown, M. W., et al. (2017). Soil protistology rebooted: 30 fundamental questions to start with. Soil Biology and Biochemistry, (111), 94–103.
Binet, P., Rouifed, S., Jassey, V. E. J., Toussaint, M.-L., & Chiapusio, G. (2017). Experimental climate warming alters the relationship between fungal root symbiosis and Sphagnum litter phenolics in two peatland microhabitats. Soil Biology and Biochemistry, 105(C), 153–161. http://doi.org/10.1016/j.soilbio.2016.11.020
Gałka, M., Tobolski, K., Lamentowicz, Ł., Ersek, V., Jassey, V. E. J., van der Knaap, W. O., & Lamentowicz, M. (2017). Unveiling exceptional Baltic bog ecohydrology, autogenic succession and climate change during the last 2000 years in CE Europe using replicate cores, multi-proxy data and functional traits of testate amoebae. Quaternary Science Reviews, 156, 90–106.
Bragazza, L., Buttler, A., Robroek, B. J. M., Albrecht, R., Zaccone, C., Jassey, V. E. J., & Signarbieux, C. (2017). Response to Editor to the comment by Delarue (2016) to our paper entitled “Persistent high temperature and low precipitation reduce peat carbon accumulation”. Global Change Biology, (in press).
Allelochemical arms race in peatlands: the role of polyphenols in aboveground-belowground interactions (SPHAGNOL)
Research efforts on allelochemical interactions in ecosystems mostly involved vascular plants rather than non-vascular plants. However, bryophytes represent a crucial group of plants, are found in many ecosystems, and posses allelochemical interactions. In Sphagnol, we envisage that polyphenols play a significant role in the competition between Sphagnum mosses and Sphagnum-vascular plant competition. More specifically, we hypothesize that species-specific polyphenols invoke a home-advantage for the producing species, directly or indirectly, by hampering growth or growth related processes of competing species. The aims of this project are (i) to determine if Sphagnum species-specific secondary metabolites are allelopathic to competing species, (ii) to understand if species-specific polyphenol production of dominant species is the major driver of the growth of the competing species. It is envisaged that this effect is driven by two key processes; direct inhibitory effects on photosynthesis rates, and impacts on microbial abundance, diversity, trophic links and activities, which in turn will affect Sphagnum competitive strength. Finally, we will determine (iii) if climate changes affect the allelochemical arms race in Sphagnum communities. Species susceptible to drought and high temperature are hypothesized to lose their competitive advantage provided by phenolics, due to direct effects of climate changes on phenolic synthesis, thereby leading to a modification of the Sphagnum–Sphagnum and Sphagnum-microbe(s) interactions.
Influence of global warming and drought on carbon sequestration and biodiversity of Sphagnum peatlands present, past and future perspectives (CLIMPEAT)
In the proposed research we want to use Sphagnum peatlands (located in N Poland) as a model ecosystem and analyze its vulnerability to climate change applying an experimental setup that simulates in situ an increase of temperature and drought. The underlying idea is to determine to what extent climate warming in combination with drought can modify peatland functioning in a polish bog which fits in an oceanic-continental climate gradient with similar studies underway in other climate settings, such as in the Jura and in Russia. In particular we want to see how these climate changes can deteriorate the C sink function of peatland ecosystems. More precisely, the project aims at evaluating the effects on (1) the balance of C fluxes above- and belowground (especially via respired CO2), (2) the biodiversity and microbial activities on Sphagnum and in the peat, (3) the structure of plant communities and primary production, and (4) dynamics of labile and recalcitrant organic matter (OM) of the peat substrate. Simultaneously, the study of the most useful biological and geochemical compartments will lead to better identification and calibration of markers of temperature-drought-induced changes (e.g. testate amoebae community structure, isotopic composition of organic compounds). The patterns of the identified proxies will be used to reconstruct climate changes during the last 1000 years. It is still not clear how fast peatlands respond to changes in temperature and droughts in continental climate setting and indeed this is an important issue, since continental regions account for a significant proportion of all northern hemisphere peatlands.