Résumé
[ES] Las poblaciones de plantas reaccionan al cambio climático de muy diversas maneras, y para evaluarlas es crucial comprender cómo se comportan los individuos en las distintas condiciones. El rendimiento fenotípico podría tener una base genética o estar influenciado únicamente por el medio ambiente (Plasticidad). Conocer el potencial del acervo genético de los diferentes grupos genéticos repartidos por los gradientes climáticos es significativo para determinar la adaptación o la plasticidad. El manzano cultivado (Malus domestica Borkh.) tiene cruces de hibridación natural con el manzano cangrejo europeo Malus sylvestris y parientes silvestres Malus orientalis, y M. sylvestris todos conservados en el huerto de manzanas silvestres de Saclay instalado en noviembre de 2020 en Francia. Se plantaron poblaciones de dos especies de parientes silvestres del manzano (M. orientalis, M. sylvestris) y de manzana comercial domesticada (M. domestica) procedentes de 4 lugares (Rumanía, Francia, Armenia, Dinamarca), en la estación biológica francesa ECOTRON, celdas de simulación climática de la temperatura y la humedad. Se recogieron muestras de hojas para extraer ARN
El objetivo principal de este estudio era determinar las diferencias en la expresión génica y los rasgos ecofisiológicos entre las poblaciones de manzanas silvestres M. sylvestris, M. orientalis y la manzana comercial M. domestica debido a la variación climática en la estación biológica ECOTRON. Se comprobó la coexpresión diferencial de genes que influyen en la mayoría de los rasgos fenotípicos para detectar la adaptación entre poblaciones o la plasticidad fenotípica. Se midieron los rasgos ecofisiológicos superficie foliar, fotosíntesis, flavonoides, e índice de balance de nitrógeno (NBI), tasa de crecimiento (absoluta y relativa) y, absorción de carbono/nitrógeno, para determinar el rendimiento fenotípico. Se determinaron los patrones de adaptación local para la supervivencia de las poblaciones de manzanas silvestres francesas y danesas, mientras que la mala adaptación de la manzana silvestre rumana. La manzana cultivada y la manzana silvestre del Cáucaso presentaron altas tasas de supervivencia independientemente del clima, lo que sugiere una gran plasticidad. También demostramos que las manzanas silvestres presentan un alto nivel de plasticidad al clima en las primeras etapas de crecimiento, y que existían compensaciones entre la altura y el número de hojas. Todas las variaciones en el fenotipo entre ambientes y la expresión genética de las plantas de manzana serán una posible fuente de información que puede utilizarse en los programas de mejora de cultivos
Auteurs, date et publication :
Auteurs Luis Jorge Sandoval Aguirre
Date : 2022
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
This study has been performed in the framework of a research program aiming to develop a low-cost aerial sensor for the monitoring of cyanobacteria in freshwater ecosystems that could be used for early detection. Several empirical and mechanistic remote-sensing tools have been already developed and tested at large scales and have proven useful in monitoring cyanobacterial blooms. However, the effectiveness of these tools for early detection is hard to assess because such work requires the detection of low concentrations of characteristic pigments amid complex ecosystems exhibiting several confounding factors (turbidity, blooms of other species, etc.). We developed a framework for performing high-throughput measurements of the absorbance and reflectance of small volumes (∼ = 20 mL) of controlled mixtures of phytoplankton species and studied the potential of this framework to validate remote-sensing proxies of cyanobacteria concentration. The absorption and reflectance spectra of single and multiple cultures carried a specific signal that allowed for the quantitative analysis of culture mixes. This specific signal was shown to be related to known pigment absorbance spectra. The concentrations of chlorophyll-a and -b, phycocyanin and phycoerythrin could be obtained from direct absorbance measurements and were correlated with the concentration obtained after pigment extraction (R2 ≥ 0.96 for all pigments). A systematic test of every possible two-band and three-band normalized difference between optical indices was then performed, and the coincidental correlation with chlorophyll-b (absent in cyanobacteria) was used as an indicator of non-specificity. Two-band indices were shown to suffer from non-specificity issues and could not yield strong and specific relationships with phycocyanin or phycoerythrin (maximum R2 0.8).
Auteurs, date et publication :
Auteurs Gabriel Hmimina , Florence D. Hulot , Jean François Humbert , Catherine Quiblier , Kevin Tambosco , Bruno J. Lemaire , Brigitte Vinçon-Leite , Louise Audebert , Kamel Soudani
Publication : Water Research
Date : 2019
Volume : 148
Pages : 504-514
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENS #PLANAQUAAuteurs, date et publication :
Auteurs Olivier Ravel , Simon Chollet , R Mosseri , M. Bouzeghoub
Date : 2025
Pages : 242-243
Catégorie(s)
#CNRS #Ecotron de Montpellier #Ecotron IleDeFrance #ENSRésumé
L'augmentation des émissions anthropiques de CO2 dans l'atmosphère accélère le changement climatique. Les sols contiennent trois fois plus de carbone que l'atmosphère et constituent donc un réservoir d'importance cruciale pour la régulation du climat. Il existe actuellement une réflexion pour stocker le carbone dans les couches profondes du sol, notamment via la rhizodéposition des plantes. Nous avons donc mené une expérience au CEREEP-Ecotron Ile-de-France pour quantifier les apports, et la persistance, du carbone rhizodéposé par les plantes à l'aide d'un marquage continu au 13C-CO2. Pour ce faire, deux variétés de blé aux systèmes racinaires contrastés ont été plantés dans des mésocosmes et cultivés pendant une saison de croissance complète et sous atmosphère enrichie en 13C. Nos objectifs étaient de quantifier le flux de carbone de l'atmosphère vers le sol et de mesurer sa persistance à court terme. Nos résultats suggèrent que la variété ancienne Plantahof rhizodépose une quantité plus élevée de carbone par rapport à la variété récente Nara notamment en profondeur. Cependant, le carbone apporté au sol par ces deux variétés a conduit à des pertes par minéralisation et des priming effects similaires. Ainsi, le bilan total du carbone était plus affecté par la profondeur du sol que les variétés utilisées dans l'étude. Par ailleurs, j'ai étudié, à partir d'une analyse bibliographique, la distribution selon la profondeur des activités enzymatiques hydrolases et oxydoréductases impliquées dans les cycles du carbone, de l'azote et du phosphore en fonction de la profondeur du sol. Les résultats de cette analyse ont montré que les profils d'activité dépendaient très fortement de la façon dont ces activités étaient exprimées, avec des activités qui diminuent avec la profondeur lorsqu'exprimées par masse de sol alors qu'elles sont plutôt stables, voire augmentent, lorsque exprimé par rapport à la biomasse microbienne. Pris dans leur ensemble, ces résultats montrent que la prise en compte du fonctionnement sur l'intégralité de la colonne de sol est indispensable pour comprendre la dynamique du carbone dans les écosystèmes terrestres.
Auteurs, date et publication :
Auteurs Fatima El Mekdad , Naoise Nunan , Xavier Raynaud
Date : 2023
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Persistence of biochar: Mechanisms, measurements, predictions
Auteurs, date et publication :
Auteurs Johannes Lehmann , Samuel Abiven , Elias Sebastian Azzi , Yunying Fang , Bhupinder Pal Singh , Saran Sohi , Cecilia Sundberg , Dominic Woolf , Andrew R. Zimmerman
Date : 2025
Pages : 277-311
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Partitioning soil organic carbon (SOC) in fractions with different biogeochemical stability is useful to better understand and predict SOC dynamics and provide information related to soil health. Multiple SOC partition schemes exist, but few of them can be implemented on large sample sets and therefore be considered relevant options for soil monitoring. The well-established particulate organic carbon (POC) vs. mineral-associated organic carbon (MAOC) physical fractionation scheme is one of them. Introduced more recently, Rock-Eval® thermal analysis coupled with the PARTYSOC machine learning model can also fractionate SOC into active (Ca) and stable SOC (Cs). A debate is emerging as to which of these methods should be recommended for soil monitoring. To investigate the complementarity or redundancy of these two fractionation schemes, we compared the quantity and environmental drivers of SOC fractions obtained on an unprecedented dataset from mainland France. About 2000 topsoil samples were recovered all over the country, presenting contrasting land cover and pedoclimatic characteristics, and analysed. We found that the environmental drivers of the fractions were clearly different, the more stable MAOC and Cs fractions being mainly driven by soil characteristics, whereas land cover and climate had a greater influence on more labile POC and Ca fractions. The stable and labile SOC fractions provided by the two methods strongly differed in quantity (MAOC/Cs=1.88 ± 0.46 and POC/Ca=0.36 ± 0.17; n=843) and drivers, suggesting that they correspond to fractions with different biogeochemical stability. We argue that, at this stage, both methods can be seen as complementary and potentially relevant for soil monitoring. As future developments, we recommend comparing how they relate to indicators of soil health such as nutrient availability or soil structural stability and how their measurements can improve the accuracy of SOC dynamics models.
Auteurs, date et publication :
Auteurs Amicie A. Delahaie , Lauric Cécillon , Marija Stojanova , Samuel Abiven , Pierre Arbelet , Dominique Arrouays , François Baudin , Antonio Bispo , Line Boulonne , Claire Chenu , Jussi Heinonsalo , Claudy Jolivet , Kristiina Karhu , Manuel Martin , Lorenza Pacini , Christopher Poeplau , Céline Ratié , Pierre Roudier , Nicolas P. A. Saby , Florence Savignac
Publication : SOIL
Date : 2024
Volume : 10
Issue : 2
Pages : 795-812
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
In the subsurface, water content, gas solubility, organic mater
degradation as well as plant and microorganism respiration control
gas fluxes between soil and the atmosphere. Indeed, all of this
controls the partial pressures of major gas species, such as O2 and
CO2 , which controls in turn the advective and diffusive transport of
all the gaseous species, including the inert gases. Because these
processes vary in intensity with time and space, it is very
challenging to define where, when and how to measure gas fluxes
between soil and the atmosphere. This is equaly important for
detection of anomalous fluxes as well as for the calculation of
relevant mass budgets. We focus here on inert gases because of their
relevance as tracers for a large variety of processes. An
experimental setup was developed and validated at the ECOTRON
IleDeFrance research center. It is composed of a 60-cm high and 40-cm
diameter sand column placed under controlled conditions (water
content, temperature, pressure, light) in a climatic chamber. Plants
are grown at the top of the column. An inert gas (SF6) is injected at
the bottom and its flux is continuously monitored at the surface. A
similar experimental setup is run without plants. Effects of
watering, daytime/nighttime plant activity, cut out of leaves, plant
destruction as well as of other solicitations are determined and
discussed. First-order models are proposed and their results are
compared to the experimental data. These models are based on
consumption of O2 , production of CO2 with a higher solubility in
water and their effects on inert gas advection-dispersion.
Auteurs, date et publication :
Auteurs Clément Alibert , Eric Pili , Pierre Barré , Florent Massol
Date : 2018
Volume : 20
Pages : 2177
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Climate change that we are facing is expected to influence multiple environmental processes, including weathering and
soil formation. While temperature and partial pressure of CO2 in the atmosphere are expected to directly influence
dissolution, in the soils their effect is compounded by plant response to environmental change. In order to evaluate effect
of temperature and CO on rock dissolution, plant growth and nutrient uptake, we conducted mesocosm experiments
2where we exposed three different plants grown in unweathered basalt tephra, as well as unplanted but not sterilized
control, to following conditions: two different CO2 levels, 400 ppm and 800 ppm, and two climate regimes, with ambient
(21-25°C) and elevated (25-30°C) temperatures. Tight control on the environmental variables was possible by conducting
experiments at the ECOTRON Ile-De-France facility, France. Studied plants included velvet mesquite (Prosopis velutina),
green spangletop (Leptochloa dubia), and alfalfa (Medicago sativa). Both mesquite and alfalfa were inoculated with the
nitrogen-fixing bacteria. Pore water solution and leachates were collected at set intervals and analyzed to determine pH,
conductivity, and concentrations of C, N, and lithogenic elements. At the end of the experiment, all plant biomass was
collected, dried, weighed, and subsamples digested to determine nutrient uptake by the plants. Soils were also analyzed
for changes in organic and inorganic C and total N content. We observed significant increase in solution concentrations for
several lithogenic elements, such as Si, Mg, and P with increase in temperature. Concentrations in the biomass were also
increased for many elements. However, biomass production was smaller at elevated temperature for alfalfa, resulting in
less treatment difference when total uptake by the plants was compared. Fewer effects of elevated CO were measured;
2among them was greater carbonate precipitation in the soil. This study indicates that climate change would affect both abiotic and biotic components of soil formation.
Auteurs, date et publication :
Auteurs K. Dontsova , Sabrina Juarez , E. Villasenor , J.-F. Le Galliard , Simon Chollet , Mathieu Llavata , Florent Massol , E. Hunt , Pierre Barré , D. Daval , A. Gelabert , G. Barron-Gafford , J. van Haren , P. Troch , R. Ferriere
Date : 2025
Catégorie(s)
#⛔ No DOI found #CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Baptiste Hulin , Samuel Abiven
Date : 2023
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Under higher atmospheric CO2 concentrations, increases in soil moisture and, hence in terrestrial-aquatic carbon transfer are probable. In a coupled terrestrial-aquatic experiment we examined the direct (e.g. through changes in the CO2 water concentration) and indirect (e.g. through changes in the quality and quantity of soil leachates) effects of elevated CO2 on a lake microbial community. The incubation of soils under elevated CO2 resulted in an increase in the volume of leachates and in both chromophoric dissolved organic matter (CDOM) absorption and fluorescence in leachate. When this leachate was added to lake water during a 3-day aquatic incubation, we observed negative direct effects of elevated CO2 on photosynthetic microorganism abundance and a positive, indirect effect on heterotrophic microbial community cell abundances. We also observed a strong, indirect impact on the functional structure of the community with higher metabolic capacities under elevated CO2 along with a significant direct effect on CDOM absorption. All of these changes point to a shift towards heterotrophic processes in the aquatic compartment under higher atmospheric CO2 concentrations.
Auteurs, date et publication :
Auteurs Emma Rochelle-Newall , Audrey Niboyet , Ludwig Jardiller , Sarah Fiorini , Simon Chollet , Mathieu Llavata , Elisa de Santis , Sébastien Barot , Gérard Lacroix
Publication : Aquatic Sciences
Date : 2018
Volume : 80
Issue : 3
Pages : 27