Résumé
Biochar is the product of intentional pyrolysis of organic feedstocks. It is made under controlled conditions in order to achieve desired physico-chemical characteristics. These characteristics ultimately affect biochar properties as a soil amendment. When biochar is used for carbon storage, an important property is its persistence in soil, often described by the proportion of biochar carbon remaining in soil after a 100 years (Fperm mathrmF_mathrmperm ). We analyzed published data on 1230 biochars to re-evaluate the effect of pyrolysis parameters on biochar characteristics and the possibility to predict Fperm mathrmF_mathrmperm from the maximum temperature reached during pyrolysis (HTT). We showed that biochar ash and nitrogen (N) contents were mostly affected by feedstock type. The oxygen to carbon (O:C) and hydrogen to carbon (H:C) ratios were mostly affected by the extent of pyrolysis (a combination of HTT and pyrolysis duration), except for non (ligno)cellulosic feedstocks (plastic waste, sewage sludge). The volatile matter (VM) content was affected by both feedstock type and the extent of pyrolysis. We demonstrated that HTT is the main driver of H:C – an indicator of persistence – but that it is not measured accurately enough to precisely predict H:C, let alone persistence. We examined the equations to estimate Fperm mathrmF_mathrmperm available in the literature and showed that Fperm mathrmF_mathrmperm calculated from HTT presented little agreement with Fperm mathrmF_mathrmperm calculated from H:C. The sign and magnitude of the bias depended on the equation used to calculate Fperm mathrmF_mathrmperm and the dispersion was usually large. This could lead to improper compensation of carbon emissions and wrong reporting of carbon sinks in national carbon accounting schemes. We recommend not to use HTT as a predictor for persistence and stress the importance to rapidly develop more accurate proxies of biochar C persistence in soil.
Auteurs, date et publication :
Auteurs Johanne Lebrun Thauront , Gerhard Soja , Hans-Peter Schmidt , Samuel Abiven
Publication : GCB Bioenergy
Date : 2025
Volume : 16
Issue : 11
Pages : e13170
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Alexandru Milcu , Ruben Puga-Freitas , Aaron M. Ellison , Manuel Blouin , Stefan Scheu , Grégoire T. Freschet , Laura Rose , Sebastien Barot , Simone Cesarz , Nico Eisenhauer , Thomas Girin , Davide Assandri , Michael Bonkowski , Nina Buchmann , Olaf Butenschoen , Sebastien Devidal , Gerd Gleixner , Arthur Gessler , Agnès Gigon , Anna Greiner
Publication : Nature Ecology & Evolution
Date : 2025
Volume : 2
Issue : 2
Pages : 279-287
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Marta Gallardo Ruiz , Jean-François Le Galliard , Thomas Tully
Publication : Pedobiologia
Date : 2025
Volume : 61
Pages : 33-41
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Marcus Schiedung , Severin-Luca Bellè , Samuel Abiven
Date : 2022
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Soil enzymes are major contributors the decomposition of soil organic matter. They are believed to reflect microbial nutrient and energy acquisition strategies and limitations. Whilst enzyme activities in surface soil layers have been widely studied, activities down the soil profile have received far less attention. Here, we present the results of a meta-analysis of hydrolase and oxidoreductase activities involved in the C, N and P cycles as a function of soil depth. The aim of the analysis was to understand how the relationship between microbial communities and their nutritional environment changes with depth. We assembled a database of 210 soil profiles published in 40 studies from diverse locations, soil types, land uses and climates. In order to compare activity profiles, we used Gaussian process regression, followed by hierarchical clustering. Our results show that, when expressed per soil mass, the majority of hydrolase activities decrease with increasing soil depth. However, this is not the case for a majority of oxidoreductase activities, possibly indicative of changes in microbial community resource acquisition strategies with depth. Microbial biomass specific enzyme activities tended to increase with soil depth, suggesting an increase in microbial allocation to resource acquisition in response to decreased resource (C, N and P) availability and/or an increased enzyme stabilization on mineral and organic surfaces.
Auteurs, date et publication :
Auteurs Fatima El Mekdad , Naoise Nunan , Samuel Abiven , Xavier Raynaud
Date : 2022
Catégorie(s)
#CNRS #Ecotron IleDeFranceRésumé
BEMEVO : Bio-indication et Effet Mémoire d'une Exposition des Végétaux cultivés à l'Ozone
Auteurs, date et publication :
Auteurs Jean-Jacques Bessoule , Simon Chollet , Amandine Hansart , Marina Le Guedard , Luis Leitao , Juliette Leymarie , Ruben Puga Freitas , Anne Repellin
Date : 2025
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Plants play an important role in carbon and nitrogen fluxes in the
environment. Plants remove carbon from the atmosphere through
photosynthesis and deposit a fraction of this carbon into the soil as a
result of root exudation and senescence, contributing to soil formation.
Additionally, plants can facilitate sequestration of CO2 from the
atmosphere in inorganic form during the process of mineral weathering.
With increasing temperatures and levels of CO2 in the atmosphere, it is
unknown what effect these changes will have on plant growth and
weathering of silicate rocks, and by extension on carbon accumulation in
the soils. To identify climate change effects on C and N fluxes, a
controlled study was conducted at Ecotron Ile-de-France utilizing
mesocosms maintained at elevated and ambient CO2 concentration and
temperature with four different vegetation treatments: control, alfalfa,
velvet mesquite, and green sprangletop. Each experiment lasted for 4
months with monthly rainfall events using deionized water. After each
rain, soil solution and drainage were collected and analyzed for major
and trace elements, as well as anions, nitrogen, and organic and
inorganic carbon. CO2 concentrations in the soil air were monitored as
well. At the end of this study, soil samples were collected from each
mesocosm at four different depths and then analyzed for organic carbon,
inorganic carbon, and total nitrogen. Accumulation of organic and
inorganic carbon and nitrogen with clear differences with depth was
observed in all mesocosms. Elevated CO2 in the atmosphere influenced C
accumulation in the soils, while the type of vegetation significantly
affected concentrations of nitrogen and organic carbon in soil and
solution. This indicates that climate change would affect carbon and
nitrogen fluxes in the soils causing feedbacks to the atmospheric CO2.
Auteurs, date et publication :
Auteurs R. Hingley , S. Juarez , K. Dontsova , E. Hunt , J. F. Le Galliard , S. Chollet , A. Cros , M. Llavata , F. Massol , P. Barré , A. Gelabert , D. Daval , P. A. A. Troch , G. Barron-Gafford , J. L. M. Van Haren , R. Ferrière
Date : 2016
Volume : 53
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Abstract. Intraspecific trait variation has large effects on the ecosystem and is greatly affected by human activities. To date, most studies focused on single
Auteurs, date et publication :
Auteurs Beatriz Diaz Pauli , Eric Edeline , Charlotte Evangelista
Publication : Conservation Physiology
Date : 2020
Volume : 8
Issue : 1
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSRésumé
Ecosystems integrity and services are threatened by anthropogenic global changes. Mitigating and adapting to these changes requires knowledge of ecosystem functioning in the expected novel environments, informed in large part through experimentation and modelling. This paper describes 13 advanced controlled environment facilities for experimental ecosystem studies, herein termed ecotrons, open to the international community. Ecotrons enable simulation of a wide range of natural environmental conditions in replicated and independent experimental units whilst simultaneously measuring various ecosystem processes. This capacity to realistically control ecosystem environments is used to emulate a variety of climatic scenarios and soil conditions, in natural sunlight or through broad spectrum lighting. The use of large ecosystem samples, intact or reconstructed, minimises border effects and increases biological and physical complexity. Measurements of concentrations of greenhouse trace gases as well as their net exchange between the ecosystem and the atmosphere are performed in most ecotrons, often quasi continuously. The flow of matter is often tracked with the use of stable isotope tracers of carbon and other elements. Equipment is available for measurements of soil water status as well as root and canopy growth. The experiments run so far emphasize the diversity of the hosted research. Half of them concern global changes, often with a manipulation of more than one driver. About a quarter deal with the impact of biodiversity loss on ecosystem functioning and one quarter with ecosystem or plant physiology. We discuss how the methodology for environmental simulation and process measurements, especially in soil, can be improved and stress the need to establish stronger links with modelling in future projects. These developments will enable further improvements in mechanistic understanding and predictive capacity of ecotron research which will play, in complementarity with field experimentation and monitoring, a crucial role in exploring the ecosystem consequences of environmental changes.
Auteurs, date et publication :
Auteurs Jacques Roy , François Rineau , Hans J. De Boeck , Ivan Nijs , Thomas Pütz , Samuel Abiven , John A. Arnone , Craig V. M. Barton , Natalie Beenaerts , Nicolas Brüggemann , Matteo Dainese , Timo Domisch , Nico Eisenhauer , Sarah Garré , Alban Gebler , Andrea Ghirardo , Richard L. Jasoni , George Kowalchuk , Damien Landais , Stuart H. Larsen
Publication : Global Change Biology
Date : 2025
Volume : 27
Issue : 7
Pages : 1387-1407
Catégorie(s)
#ANR-Citation #CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Alexia Stokes , Sébastien Barot , Jean-Christophe Lata , Gérard Lacroix , Clive G. Jones , William J. Mitsch
Publication : Ecological Engineering
Date : 2025
Volume : 45
Pages : 1-4