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2. Current knowledge and future research opportunities for modeling annual crop mixtures. A review

Author

Gaudio, Noémie, Escobar-Gutiérrez, Abraham J., Casadebaig, Pierre, Evers, Jochem B., Gérard, Frédéric, Louarn, Gaëtan, Colbach, Nathalie, Munz, Sebastian, Launay, Marie, Marrou, Hélène, Barillot, Romain, Hinsinger, Philippe, Bergez, Jacques-Eric, Combes, Didier, Durand, Jean-Louis, Frak, Ela, Pagès, Loïc, Pradal, Christophe, Saint-Jean, Sébastien, Van Der Werf, Wopke, and Justes, Eric

Subjects
Quantitative Biology - Populations and Evolution, Quantitative Biology - Quantitative Methods
Abstract

Growing mixtures of annual arable crop species or genotypes is a promising way to improve crop production without increasing agricultural inputs. To design optimal crop mixtures, choices of species, genotypes, sowing proportion, plant arrangement, and sowing date need to be made but field experiments alone are not sufficient to explore such a large range of factors. Crop modeling allows to study, understand and ultimately design cropping systems and is an established method for sole crops. Recently, modeling started to be applied to annual crop mixtures as well. Here, we review to what extent crop simulation models and individual-based models are suitable to capture and predict the specificities of annual crop mixtures. We argued that: 1) The crop mixture spatio-temporal heterogeneity (influencing the occurrence of ecological processes) determines the choice of the modeling approach (plant or crop centered). 2) Only few crop models (adapted from sole crop models) and individual-based models currently exist to simulate annual crop mixtures. 3) Crop models are mainly used to address issues related to crop mixtures management and to the integration of crop mixtures into larger scales such as the rotation, whereas individual-based models are mainly used to identify plant traits involved in crop mixture performance and to quantify the relative contribution of the different ecological processes (niche complementarity, facilitation, competition, plasticity) to crop mixture functioning. This review highlights that modeling of annual crop mixtures is in its infancy and gives to model users some important keys to choose the model based on the questions they want to answer, with awareness of the strengths and weaknesses of each of the modeling approaches., Comment: 42 pages, 5 figures

Published
2019
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5. Comparison of numerical simulations of reactive transport and chemostat-like models

Author

Haidar, Ihab, Gérard, Frédéric, and Rapaport, Alain

Subjects
Mathematics - Dynamical Systems, Physics - Geophysics, Quantitative Biology - Quantitative Methods
Abstract

The objective of the paper is to evaluate the ability of reactive transport models and their numerical implementations (such as MIN3P) to simulate simple microbial transformations in conditions of chemostat or gradostat models, that are popular in microbial ecology and waste treatment ecosystems. To make this comparison, we first consider an abstract ecosystem composed of a single limiting resource and a single microbial species that are carried by advection. In a second stage, we consider another microbial species in competition for the same limiting resource. Comparing the numerical solutions of the two models, we found that the numerical accuracy of simulations of advective transport models performed with MIN3P depends on the evolution of the concentrations of the microbial species: when the state of the system is close to a non-hyperbolic equilibrium, we observe a numerical inaccuracy that may be due to the discretization method used in numerical approximations of reactive transport equations. Therefore, one has to be cautious about the predictions given by the models.

Published
2011

16. Preferential flow revealed by hydrologic modeling based on predicted hydraulic properties

Author

Gerard, Frederic, Tinsley, Mark, and Mayer, K. Ulrich

Subjects
Soils -- Research, Earth sciences
Abstract

Pedotransfer functions have shown a reasonable reliability and accuracy for predicting soil hydraulic properties. However, the contribution of the range of macroscopic features leading to preferential water flow is not readily taken into account. We modified and used the hydrological component of the reactive transport model MIN3P and the neural network-based code ROSETYA in an attempt to simulate 4 yr of daily measurements of the soil water content in a forest soil covered by Douglas-fir (Psendotsaga menziessii Franco). A good fit of the mean measured water contents was obtained during periods of low soil moisture, while the model tended to overpredict water contents during periods of high soil moisture. This behavior is typical for the presence of significant preferential flow. Slightly better results were obtained by using predicted values of the saturated hydraulic conductivity, while the assumption of a water table located at shallow depth increased discrepancies. A good match was obtained by calibration of a simple preferential flow scheme, which was based on the assumption that the retention properties of the porous network control preferential flow. Accordingly, preferential flow seemed to initiate within the capillary pore domain. This causes a much greater sensitivity of the results to the position of the water table than with other schemes that consider pure gravity-driven flow in large macropures. Knowledge of the functional pore size is needed to ascertain the type of preferential flow scheme to be used.

Published
2004

17. Accounting for natural organic matter in aqueous chemical equilibrium models: a review of the theories and applications

Author

Dudal, Yves and Gerard, Frederic

Subjects
Soils, Soil chemistry, Organic acids, Acetohydroxamic acid, Coordination compounds, Humic acid, Earth sciences
Abstract

Soil organic matter consists of a highly complex and diversified blend of organic molecules, ranging from low molecular weight organic acids (LMWOAs), sugars, amines, alcohols, etc., to high apparent molecular weight fulvic and humic acids. The presence of a wide range of functional groups on these molecules makes them very reactive and influential in soil chemistry, in regards to acid-base chemistry, metal complexation, precipitation and dissolution of minerals and microbial reactions. Out of these functional groups, the carboxylic and phenolic ones are the most abundant and most influential in regards to metal complexation. Therefore, chemical equilibrium models have progressively dealt with organic matter in their calculations. This paper presents a review of six chemical equilibrium models, namely NICA-Donnan, EQ3/6, GEOCHEM, MINTEQA2, PHREEQC and WHAM, in light of the account they make of natural organic matter (NOM) with the objective of helping potential users in choosing a modelling approach. The account has taken various faces, mainly by adding specific molecules within the existing model databases (EQ3/6, GEOCHEM, and PHREEQC) or by using either a discrete (WHAM) or a continuous (NICA-Donnan and MINTEQA2) distribution of the deprotonated carboxylic and phenolic groups. The different ways in which soil organic matter has been integrated into these models are discussed in regards to the model-experiment comparisons that were found in the literature, concerning applications to either laboratory or natural systems. Much of the attention has been focused on the two most advanced models, WHAM and NICA-Donnan, which are able to reasonably describe most of the experimental results. Nevertheless, a better knowledge of the humic substances metal-binding properties is needed to better constrain model inputs with site-specific parameter values. This represents the main axis of research that needs to be carried out to improve the models. In addition to humic substances, more non-humic compounds should also be introduced in model databases, notably the ones that readily interact with the soil microorganisms. Thermodynamic data are generally available for most of these compounds, such as low molecular-weight organic acids. However, the more complex non-humic substances, exhibiting a ratio of hydrophobic versus hydrophilic bonds lower than humic substances, need to be further characterised for a comprehensive implementation in chemical equilibrium models. Keywords: Modelling; Metal complexing; Organic acids; Humic acids; Soils; Aqueous solutions

Published
2004

18. Reactive transport modeling the oxalate-carbonate pathway of the Iroko tree

Author

Gatz-Miller, Hannah, Gerard, Frederic, Verrechia, Eric, Mayer, Klaus Ulrich, EOAS, University of British Colombia, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université de Lausanne (UNIL), and Université de Lausanne = University of Lausanne (UNIL)

Subjects
[SDV.BV]Life Sciences [q-bio]/Vegetal Biology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

19. Modeling the key role of microorganisms in organic storage of soil and plant nutrition

Author

Pansu, Marc, Ibrahim, Hatem, Drevon, Jean-Jacques, Gerard, Frederic, Blavet, Didier, Institut de Recherche pour le Développement (IRD), Université de Carthage - University of Carthage, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), and ProdInra, Migration

Subjects
[SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

21. Reactive transport modeling the oxalate carbonate pathway to assess carbon sequestration by the Iroko tree

Author

Gatz-Miller, Hannah, Gerard, Frederic, Verrechia, Eric, Mayer, Klaus Ulrich, EOAS, University of British Colombia, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université de Lausanne (UNIL), University of British Columbia (UBC), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and ProdInra, Archive Ouverte

Subjects
[SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

A reactive transport (RT) model of the oxalate-carbonate pathway (OCP) of the Iroko tree in the Ivory Coast, Africa, was constructed to evaluate rates and amounts of biogenically-induced calcite formation. Previous field and laboratory works indicate that the OCP mediates biomineralization via calcium uptake by roots and formation of calcium oxalate crystals in plant tissues. This leads to litter fall containing calcium oxalate particles, and then oxalate release and oxidation in the soil, resulting in the formation of calcite in soils where no calcite was previously present. Any carbon stored as calcite in soil, would appear to be a viable form of carbon capture over and beyond the life cycle of the tree. The RT model focused on quantitatively evaluating the fluxes and fate of calcium and carbon in the different components of the OCP process, to assess how much carbon may be stored in soils over the life cycle of a mature tree (170 years). To calculate a feasible mass balance, literature regarding calcium input from dust, precipitation, bedrock, and other potential sources on the Ivory Coast, was combined with average precipitation rates, soil porosity, uptake rates, litter fall rates, litter decomposition rates, and known values for the kinetics of the relevant oxidation-reduction reactions. Initial conditions (soil pH, soil pCO2, pO2, and soil water content) were set based off literature values regarding tropical ferralitic soils near the Ivory Coast. A 1-D model representing a vertical soil profile was constructed using the RT code MIN3P-THCm. Initial model results indicate that soil pH rose from an initial acidic value (4.7) to more alkaline, over 170 model years. The alkaline soil did allow calcite formation, particularly near the surface where pH was the most basic, and where calcium oxalate had explicitly been present. Levels of calcite formation dropped where calcium oxalate had been absent, despite the presence of other calcium sources in the bulk soil. Subsequent 2-D models are being constructed to further assess the spatial extent and influence of the pH change, to be coupled with a root architecture model to investigate the influence of solute uptake, and the overall role of the root system on biomineralization and the OCP of the Iroko tree.

Published
2018

23. Dynamics of CO2, CH4 and N2O concentrations throughout deep soil profiles in Eucalypt plantations subjected to contrasted rainfall regimes: consequences on soil effluxes

Author

Germon, Amandine, Jourdan, Christophe, Pagès, Loïc, Gerard, Frederic, Blitz, Céline, Chapuis-Lardy, Lydie, Nouvellon, Yann, Robin, Agnès, Rosolem, C.A., de Moraes Gonçalves, J.L., Guerrini, Irae Amaral, Laclau, Jean-Paul, Université Joseph Ki-Zerbo [Ouagadougou] (UJZK), Universidade Estadual Paulista Júlio de Mesquita Filho = São Paulo State University (UNESP), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Institut National de la Recherche Agronomique (INRA), and Universidade de São Paulo (USP)

Subjects
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, ComputingMilieux_MISCELLANEOUS
Abstract

The major factors driving greenhouse gas exchanges in forest soils (substrate supply, temperature, water content) vary with soil depth. Our study aimed to assess the effects of clear-cutting and drought on the temporal variability of CO2, CH4 and N2O fluxes throughout very deep soil profiles in Brazilian eucalypt plantations conducted in coppice. Stands with 37% of through fall excluded by plastic sheets (-W) and stands without rain exclusion (+W) were compared. Every two weeks for 21 months, CO2, CH4 and N2O surface effluxes were measured using the closed-chamber method and concentrations in the soil were measured at 7 depths down to 15.5 m in -W and +W. At most measurement dates, CO2, CH4 and N2O effluxes at the soil surface were not significantly different between -W and +W. Mean CO2 and N2O concentrations in -W were 20.7% and 7.6% lower than in +W, respectively, across the sampling depths. By contrast, CH4 concentrations in -W were 44.4% higher than in +W throughout the soil profile. Across the two treatments, CO2 concentrations increased from 4446 _ 2188 ppm at 10 cm deep to 15622 _ 3523 ppm at 15.5 m, CH4 concentrations increased from 0.41 _ 0.17 ppm at 10 cm deep to 0.77 _ 0.24 ppm at 15.5 m and N2O concentrations remained roughly constant and were on average 478 _ 55 ppb from the soil surface to 15.5 m deep. A modeling approach (using the Min3P and Root Typ models) showed that the amount of water filling soil porosity accounted for a large share of the difference in gas concentration between +W and {W, and pointed out the consequences of through fall exclusion on the areas of CO2 production throughout the soil profile. Improving our understanding of the spatiotemporal dynamics of gas concentrations in deep soil layers is important to improve the current biogeochemical models predicting the effect of drought periods on greenhouse gas effluxes in eucalypt plantations established in deep tropical soils.

Published
2018

24. Coupling reactive transport processes with root system architecture and functions: principles and application examples

Author

Gerard, Frederic, Gatz-Miller, Hannah, Kerches Braghiere, Rénato, Bea, Sergio Andres, Hinsinger, Philippe, Pagès, Loïc, Mayer, Klaus Ulrich, ProdInra, Migration, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), EOAS, University of British Colombia, Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), and Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences
Abstract

International audience; We developed a novel soil-plant interaction model based on the coupling of a root system architecture model (ArchiSimple) with a reactive transport model (Min3P). The main novelty of this macro-scale model is to facilitate the simulation of soil-plant interactions by simultaneously accounting for principles of plant biology, aqueous geochemistry and the transport of water, solutes and gases in soil. This contribution is devoted to introduce the formulation of the coupled soil-plant interaction model and to present two application examples highlighting the capabilities of this tool for tackling a wide range of agronomic and environmental issues. The first application focuses on phosphorus acquisition by annual plants from alkaline soils. In this case, we performed 2D simulations to investigate the role of common root processes (i.e., nutrient uptake and related pH changes) in releasing phosphate from the mineral and adsorbed pools in soil. Results are compared with observed data collected in the field and in the laboratory published in the literature . The second application is addressing the capacity of select plant species to induce the formation of calcium carbonates (and alkalization) in tropical soils through the oxalate-carbonate pathway (OCP). We simulate OCP for Iroko trees (Milicia excelsa), because these plants were shown capable of sequestering substantial amounts of calcium carbonate over the life-span of a tree (80 years) in Ivory Coast. Our process-based modeling investigation provides insight in elemental balances, most importantly the fate of carbonate produced by the decomposition of oxalate, which is not only sequestered in the form of calcium carbona

Published
2018

26. Processes controlling phosphate acquisition by plants as revealed by coupled root system-reactive transport modeling

Author

Gerard, Frederic, Bea, Sergio Andres, Pagès, Loïc, Hinsinger, Philippe, Mayer, Klaus Ulrich, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Consejo Nacional de Investigaciones Científicas y Técnicas, Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Institut National de la Recherche Agronomique (INRA), EOAS, University of British Colombia, and ProdInra, Migration

Subjects
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2017

27. Generic reactive transport codes as flexible tools to integrate soil organic matter degradation models with water, transport and geochemistry in soils

Author

Jacques, Diederick, Gerard, Frederic, Mayer, Klaus Ulrich, Centre d'Etude de l'Energie Nucléaire (SCK-CEN), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), EOAS, University of British Colombia, and ProdInra, Migration

Subjects
[SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences
Abstract

International audience; A large number of organic matter degradation, CO2 transport and dissolved organic matter models have been developed during the last decades. However, organic matter degradation models are in many cases hard-coded in terms of pools, kinetics and dependency on environmental variables. The input of the model user is typically limited to the adjustment of input parameters. In addition, the coupling with geochemical soil processes including aqueous speciation, sorption and colloid-facilitated transport are not incorporated in many of these models. Furthermore, these models are combined with simplified representations of flow and transport processes. We illustrate the capability of generic reactive transport codes to overcome these shortcomings. The formulations of reactive transport codes include a physics-based continuum representation of flow and transport processes, while biogeochemical reactions can be described as equilibrium processes and/or kinetic reaction networks. The flexibility of these type of codes allows for straightforward extension of reaction networks with new model components and in such a way facilitates an application-tailored implementation of organic matter degradation models and related processes. A numerical benchmark involving two reactive transport codes (HPx and MIN3P) demonstrates how the process-based simulation of transient variably saturated water flow, solute transport, heat transfer and diffusion in the gas phase can be combined with a flexible implementation of a soil organic matter degradation model. The benchmark includes the production of leachable organic matter and inorganic carbon in the aqueous and gaseous phases, as well as different decomposition functions with first-order, linear dependence or nonlinear dependence on a biomass pool. In addition, we show how processes such as local bioturbation (biodiffusion) can be included implicitly through a Fickian formulation of transport of soil organic matter. Coupling soil organic matter models with generic and flexible reactive transport codes offers a valuable tool to enhance insights into coupled physico-chemical processes at different scales within the scope of C-biogeochemical cycles, possibly linked with other chemical elements such as plant nutrients and pollutants.

Published
2016

28. A robust and parsimonious model for caesium sorption on pure clay minerals and natural clay materials

Author

CHERIF, Mohamed Amine, Martin-Garin, Arnaud, Gerard, Frederic, Bildstein, Olivier, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire de Biogéochimie, Biodisponibilité et Transfert des Radionucléides (IRSN/PRP-ENV/SERIS/L2BT), Service de Recherche et d'Expertise sur les Risques environnementaux (IRSN/PRP-ENV/SERIS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), IRSN, PRP-ENV, SERIS, L2BT, and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract

International audience; A generic model for Cs sorption onto clays Published experimental data and models for caesium sorption by pure minerals and natural clay materials were compiled and critically analyzed in an attempt to propose a generic approach. This analysis led to the construction of a new mechanistic model for Cs sorption, which combines surface complexation and cation exchange approaches involving two distinct types of surface sites, frayed edge sites (SO-0.5) and planar sites (X-- ). This model takes into account the cation competitions, as well as the effect of ionic strength and pH. We evaluated our model against Cs sorption data for three reference clay minerals (illite, smectite and kaolinite) and on natural clays materials (e.g. Callovo– Oxfordian Claystones, Hanford sediment) measured under a range of physico-chemical conditions. Results showed that our model successfully reproduces most of these experimental data both qualitatively and quantitatively. The model account for varying levels of Cs interactions with pure and natural clay substrates, without making any prior adjustment of parameters, offering a major advantage over previously developed models

Published
2016

29. Incorporating soil organic matter models in generic reactive transport codes

Author

Jacques, Diederick, Gerard, Frederic, Mayer, Klaus Ulrich, Simunek, Jirka, Centre d'Etude de l'Energie Nucléaire (SCK-CEN), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), EOAS, University of British Colombia, University of California [Riverside] (UCR), and University of California

Subjects
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

30. KIRMAT (Kinetics of Reaction and Mass Transfers)

Author

Clément, Alain, Fritz, Bertrand, Gerard, Frederic, Crovisier, Jean-Louis, ProdInra, Migration, Centre National de la Recherche Scientifique (CNRS), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
[SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], IDDN.FR.001.090017.000.R.P.2016.000.10000, [SDE]Environmental Sciences
Published
2016

31. Nutrient cycling in agroecosystems – a rhizosphere biogeochemistry perspective

Author

Hinsinger, Philippe, Pradier, Céline, Gerard, Frederic, Laclau, Jean-Paul, Jourdan, Christophe, ProdInra, Migration, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

International audience; Producing more food with less impact on ecosystem services such as the biogeochemical cycles of nutrients is a major challenge ahead of us. Some solutions to design a sustainable intensification of agroecosystems pertain in the understanding of rhizosphere ecology and biogeochemistry, as the root-soil interface is a major hotspot of biological activities in soils. The aim of this paper is to point some of the key root-mediated biogeochemical processes that could be better promoted to achieve an ecological intensification of agroecosystems. Roots can considerably alter nutrient concentrations and soil pH over short spatial and temporal scales as a result of their uptake and exudation activities. We will briefly review how these root-induced changes of rhizosphere biogeochemical properties impact : the dissolution/precipitation of soil minerals, the adsorption/desorption of ions, and hence the bioavailability of key major nutrients, either anions (e.g. phosphate) or cations (e.g. potassium). While much of the past research has been considering young plants under controlled conditions, there is a need to assess these processes under field conditions for mature plants as well, and to make better use of modelling to fully understand the complex interactions at play. We will also stress the need to get beyond the topsoil, and account for rhizosphere processes occurring at depth in the soil, and show some exciting results obtained at several meter depth. The development of novel tools and approaches will thus be instrumental, as shown through a few examples in this talk. Further understanding the rather unique rhizosphere biogeochemistry is thus pivotal to quantifying the driving role of higher plants in ecosystem services, especially support services such as soil formation and nutrient cycling. It provides exciting perspectives for breeding crops and trees that most efficiently acquire and cycle nutrients for improving the nutrient use efficiency of the agroecosystems of tomorrow.

Published
2016

32. Implementation of root system architecture and functions into the reactive transport model MIN3P: method and capabilities

Author

Gerard, Frederic, Blitz, Céline, Pagès, Loïc, Moitrier, Nicolas, Tambour, Ludovic, Loiseleur, Olivier, Hinsinger, Philippe, Screpanti, Claudio, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Institut National de la Recherche Agronomique (INRA), Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Syngenta, and ProdInra, Migration

Subjects
food and beverages, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

International audience; The dynamics of chemical species in soils is usually altered by a range of biotic processes, especially those related to the activity of plant roots (e.g. uptake, exudation, microbiologically-mediated reactions). Several models can simulate the development in space (3D) and time of root systems for most plant species but they are very limited regarding reactive transport processes. Conversely, several comprehensive reactive transport models exist for the vadose zone but none of them can readily include root growth. This communication is aimed at presenting results of the coupling of the soil version of the reactive transport model MIN3P (Mayer et al., 2012) with the root system model ArchiSimple (Pagès et al., 2014). The scientific and technical approaches used to perform this coupling will be briefly presented. Results of two example applications will be shown in order to illustrate the new capabilities. These applications will concern problems of pesticide and phosphate dynamics in the soil plant system.

Published
2015

33. Effect of the soils properties on the sorption capacity of phosphorus and ammonium by alkaline soils of the semi-arid areas

Author

Hamdi, Wissem, Ziadi, Noura, Kouakoua, Ernest, Blavet, Didier, Gerard, Frederic, Seffen, Mongi, Institut Supérieur Agronomique Chott-Mériem (ISA), Laboratoire des Energies et des Matériaux (LabEM) : LR11ES34, Université de Sousse, Soils and Crops Research and Development Centre, Agriculture and Agri-Food [Ottawa] (AAFC), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)

Subjects
Soil proprieties, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Semi-arid areas, Sorption, Phosphorus, Ammonium
Abstract

Soils samples were collected at different depths (from 0 to 120 cm) from tree sites of Tunisia (Chott Mariem, Enfidha and Kondar). The minerals and physicochemical properties were analyzed. Then the capacity sorption of phosphorus and ammonium was carried only in the samples collected from the surface depth (0-25cm) using the batch processes. The results showed that most soil samples have a clayey texture. The available of nutriment and heavy metals was different and varied with the sites and depths. The sorption of phosphorus and ammonium was rapid initially and gradually diminished to attain equilibrium. The equilibrium was reached after 72 h for phosphorus sorption and 300mn for ammonium sorption. Also the levels of P adsorbed were; 6.27, 6.84 and 6.92 mg P g−1 and ammonium adsorbed were 5.83, 6.5 and 6.3 mg NH4 + g −1 respectively from the soil Chott Mariem, Enfidha and kondar. Applications of the following kinetics models: pseudo-first-order, pseudo- second-order and Elovich model to the data show that the rates of phosphorus and ammonium sorption were best predicted by the pseudo-second-order kinetic model as seen from the correlation coefficient R2 (≥0.98).

Published
2015

34. Abiotic processes controlling the effects of citrate on phosphorus availability: study of a fertilized ferralsol

Author

Henintsoa, Manitranirina, BECQUER, Thierry, Clairotte, Michael, Larvy Delarivière, Jean, Andriamananjara, Andry, Rabeharisoa, Lilia, Gerard, Frederic, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Laboratoire des Radio-Isotopes (LRI), Université d'Antananarivo, Université d'Antananarivo, Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), LRI, Laboratoire des Radio-Isotopes, and ProdInra, Archive Ouverte

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GC] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

Organic acids exuded by roots, especially citrate, can increase P availability in soils and thus facilitate P acquisition by plants. However, controlling processes are poorly known. In order to improve this understanding, we added different citrate concentrations (2, 10, 20, 50, 100, 250 and 500 μM as trisodium citrate) to water extractions performed with a fertilized ferralitic soil. We performed the experiments at T = 2°C in order to minimize the effects of biological activity. We measured dissolved inorganic P concentrations (available P) along with the concentrations of major solutes (Na, K, Ca, Al, Fe, Si and organic carbon) and pH. We also modeledaqueous speciation and determined mineral saturation indexes. Results showed that available P gradually increases with citrate concentration. Similar trends were observed with dissolved Al, Fe, Si, organic C, and Na. In contrast, pH decreased compared to control (i.e. 0 citrate) with addition of low citrate concentrations while it became more alkaline at higher citrate concentration.Dissolved K, Mg and Ca did not show monotonous variations as well. Dissolved K gradually decreased up to 250 μM of citrate. Dissolved Ca slightly increased with low citrate concentrations, vanished at intermediate concentrations (50 and 100 μM) and finally increased markedly at high citrate concentrations. Dissolved Mg exhibited intermediate variations. Multiple linear regression analysis showed that variations of P availability were significantly correlated with dissolved Si. This result along with these of the modeling suggested that available P was mainly controlled by dissolution of P-sorbing minerals, especially kaolinite.

Published
2014

35. Représentations – Modélisation des interactions biotiques dans les sols

Author

Hinsinger, Philippe, Blanchart, Eric, Boudsocq, Simon, Gerard, Frederic, Jaillard, Benoît, Daufresne, Tanguy, Marsden, Claire, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Ecologie Fonctionnelle et Biogéochimie des Sols (Eco&Sols), and Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Ecole Nationale Supérieure Agronomique de Montpellier (ENSA M)

Subjects
interaction sol racine, [SDV]Life Sciences [q-bio], Agroécologie, modèle écophysiologique, cycle géochimique, écosystème, proie, prédateur, dynamique spatialisée, compétition source puits, modélisation, contrôle biologique, syrphe, puceron, activité microbienne du sol, modèle multiagent, biodiversité microbienne
Abstract

Session 2 : Intégration et changement d'échelles. Exemple 4.Session 2 : Intégration et changement d'échelles. Exemple 4.; absent

Published
2014

36. Earthworms modify soil phosphorus and plant interactions in a Mediterranean legume-cereal intercrop

Author

Coulis, Mathieu, Bernard, Laetitia, Gerard, Frederic, Hinsinger, Philippe, Plassard, Claude, Villeneuve, Manon, Blanchart, Eric, ProdInra, Archive Ouverte, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

Intercropping of legumes and cereals appears as an alternative agricultural practice to decrease the use of chemical fertilizers while maintaining high yields. A better understanding of the biotic and abiotic factors determining interactions between plants is required. Our study aims to analyse the effect of earthworms on the legume-cereal interactions with a focus on the modifications induced by earthworms on the forms of soil phosphorus (P). In a glasshouse experiment we investigated the effect of an endogeic earthworm(Allolobophora chlorotica) on the plant biomass and on N and P acquisition by durum wheat (Triticum turgidum durum L.) and chickpea (Cicer arietinum L.) either grown alone or intercropped. The modifications of the different organic and inorganic P forms in the bulk soil were measured. There was no overyielding of the intercrop in the absence of earthworms. Earthworms had a strong influence on biomass and resource allocation between roots and shoots whereas no modification was observed in terms of total biomass production and P acquisition. Earthworms changed the interaction between the intercropped species mainly by reducing the competition for nutrients. Facilitation (positive plant-plant interactions) was only observed for the root biomass and P acquisition in the presence of earthworms. Earthworms decreased the amount of organic P extracted with NaOH, while they increased the water soluble inorganic P content. In this experiment, earthworms could be seen as “troubleshooter” in plant-plant interaction as they reduced the competition between the intercropped species. Our study brings new insights into how earthworms affect plant growth and the P cycle.

Published
2014

37. Clay minerals and phosphate sorption in soils

Author

Gerard, Frederic, Duputel, Marek, Caner, Laurent, Kongmark, Chanapa, ProdInra, Archive Ouverte, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), ITK, Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), Synchrotron Light Research Institute (SLRI), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Université de Poitiers-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, inorganic chemicals, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, complex mixtures, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy, [SDU.STU.MI] Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract

Solubilization of soil phosphate accumulated during the last decades in fertilized soils can be profitably used to decrease phosphate (PO4) fertilization while maintaining crop production. In this respect, it is important to clearly identify and rank the different soil constituents regarding their importance for the control of PO4 sorption. However, the relative importance of clay minerals versus Fe oxide-hydroxides is still controversial. Indeed, some researchers only considered the influence of Fe oxide-hydroxides, while others also included clay minerals in their PO4 sorption models. Through this communication our main objective is to present a set of evidences issued from the literature and also based on original data which support the significant influence of clay minerals on PO4 sorption in soils. The first evidence is based on the adsorption capacity of minerals and on the mineralogical composition of soils. Second, we showed that the adsorption properties of clay minerals versus pH do not resemble to that of Fe oxide-hydroxides, thus precluding the consideration of Fe oxide-hydroxides as a surrogate for clay minerals. Last, preliminary results of synchrotron-based X-ray absorption spectroscopy at the phosphorus K-edge showed that PO4 binding to clay minerals substantially involves structural Al-O sites and not only Fe-O sites. To conclude, both Fe oxide-hydroxides and clay minerals should be considered in PO4 retention modelling in soils as they considerably influence sorption processes.

Published
2014

39. Thermodynamic modelling of P availability: the case of intercropping rhizosphere

Author

Duputel, Marek, Hinsinger, Philippe, Gerard, Frederic, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Vegetal Biology, ph du sol, Agricultural sciences, biodisponibilité du phosphore, blé dur, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, culture intercalaire, association céréales protéagineux, modèle thermodynamique, pois chiche, Sciences agricoles, Biologie végétale, qualité du sol
Abstract

Plants of chickpea and durum wheat were cultivated as sole-­‐crop and intercrop in a rhizobox deviceaccording to a substitutive design. Unplanted soil was used as a control treatment. The soil used was a noncarbonated Luvisol with a neutral pH. Plants were harvested at the chickpea flowering stage. The pH, Pavailability and dissolved Ca were measured in soil as extracted by water and CaCl2 (1 and 10 mM). A set ofthermodynamic models were used (i.e. CD MUSIC; Nica Donnan; ion exchange) to simulate and understandmeasured P availability variations in each treatment.

Published
2013

40. A model-driven decision support system for vineyard water status management: a time-dependant sensitivity analysis

Author

Guaus, Anais, Bsaibes, Aline, Cartailler, Thomas, Prieur, Clémentine, Lebon, Eric, Gerard, Frederic, Jallas, Eric, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), ITK, Modelling, Observations, Identification for Environmental Sciences (MOISE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut National Polytechnique de Grenoble (INPG), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, model, SVAT, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Sobol, water budget, grapevine
Abstract

International audience; The global sensitivity analysis of a dynamic soil water balance model embedded in a Decision Support System for vineyard water management is achieved via the Sobol variance-based method. The sensitivity analysis is applied sequentially at each simulation step so that the variation of parameter influence over time can be followed. Results allow identification of four soil-related parameters having the highest influence at the vine plot scale, and for various climate scenarios. This provides fundamental information for the operational use of the model, i.e. when few input data are available to the end-user.

Published
2013

41. Time-dependent sensitivity and uncertainty analyses of an agro-climatic model for the water status management of vineyard

Author

Guaus, Anais, Bsaibes, Aline, Cartailler, Thomas, Prieur, Clémentine, Lebon, Eric, Gerard, Frederic, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro), ITK, Modelling, Observations, Identification for Environmental Sciences (MOISE), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut National Polytechnique de Grenoble (INPG), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
vignoble, Vegetal Biology, modèle agroclimatique, pilotage de l'irrigation, climat méditerranéen, analyse de sensibilité globale, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, stress hydrique, Biologie végétale
Abstract

International audience; This work describes the global sensitivity analysis (SA) of an agro-climatic model embedded in a decision support system (DSS) for the water status management of vineyard in the Languedoc-Roussillon region, France.

Published
2013

42. Comparison of two modeling approaches for water transfer in the soil-vegetation-atmosphere continuum

Author

GUAUS, Anais, Bsaibes, Aline, Auffray, Valérie, Lebon, Eric, Gerard, Frederic, ProdInra, Archive Ouverte, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), ITK, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro), Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)

Subjects
[SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

As part of a R&D project aiming at providing vineyard managers with a computer-based decision support system for optimizing irrigation, we discuss the validity of two modeling approaches for water transfers in the soil-plant-atmosphere continuum. The two models are an empirical ‘bucketlike’ model and a mechanistic model based on the 1D Richards’ equation. The practical context implying that soil-water parameters are poorly estimated, both models are compared in terms of accuracy and parameterization cost. The models are coupled to the same canopy growth, radiation absorption, evaporation and transpiration models, and the predawn leaf water potential (PLWP) is used as the indicator of soil-water deficit. The parameters of both models are estimated with pedotransfer functions from the single texture and the only additional input for the 1D model is root repartition versus depth. A multi-factor sensitivity analysis relative to the input parameters of the soil-vegetation-atmosphere coupling shows that the hard-to-obtain rooting depth is the key factor of the PLWP sensitivity. It also shows that the computation of PLWP with the 1D model is robust against root distribution uncertainty, so that root distribution can be fixed to a mean value. The accuracy of the two models is evaluated in vineyards varying in soil type, rooting depth and irrigation procedure in the Languedoc region (France), by comparing simulated to measured values of vine transpiration and PLWP. Provided the calibration of rooting depth, both models give results coherent with field measurements, with no significant improvement when the more physical mechanistic model is used.

Published
2012

43. Adsorption du citrate et disponibilité du phosphate dans les sols : modélisation mécaniste

Author

Duputel, Marek, Devau, Nicolas, Brossard, Michel, Hinsinger, Philippe, Jaillard, Benoît, Gerard, Frederic, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)

Subjects
luvisol, modèle mécaniste, Géochimie, réaction biogéochimique, simulation, Geochemistry, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, approche additive, disponibilité d'éléments nutritifs, citrate, adsorption d'ion, cambisol, ferralsol, propriété du sol, disponibilité du phosphore
Abstract

absent

Published
2012

44. Root-mediated mobilization of soil phosphates: what did we learn from mechanistic modelling ?

Author

Gerard, Frederic, ProdInra, Archive Ouverte, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology
Abstract

Phosphorus is limiting plant growth in many soils. The perspective of scarcity of the P-ore (phosphate rock) reserves urges us to find an alternative to P fertilization, or at least to decrease it while keeping the same yield. An option is to solubilise soil P (i.e. to increase P availability) by relying on the interactions between roots activity (exudation of proton/hydroxyl, organic ligands, etc.) and P-containing soil constituents. However, P-mobilizing processes and mechanisms are poorly known and understand. Mechanistic modelling can be profitably used to fill this gap. The present communication is aimed at reviewing our recent works where we propose a mechanisticequilibrium model for simulating P availability in soil and rhizosphere. We studied neutral oxisols with contrasted mineralogical composition and P fertilization levels. A new root-mediated process, the uptake of Ca ions, was found to play a key role, as it markedly increased P availability in the rhizosphere of Durum wheat as pH increased. Model’s validity was demonstrated by modelling P availability over a range of pH values and salt concentrations.

Published
2012

45. Spatio-temporal variability of soil carbon content in an agricultural environment with carbonates examples of contributions of near infrared spectroscopy

Author

Blavet, Didier, Aholoukpé, H., Ouagga, T., Bensalah, N., Cheggour, Aouatif, Brunet, Didier, Souche, Gerard, Alary, K., Desclaux, Dominique, Gerard, Frederic, Roose, E., Simonneaux, Vincent, Brossard, Michel, Hinsinger, Philippe, Sabir, M., Bernoux, Martial, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut National des Recherches Agricoles du Bénin (INRAB), Ecole Nationale Forestière d'Ingénieurs du Maroc [Salé] (ENFI), Université Cadi Ayyad [Marrakech] (UCA), Analyses des eaux, sols et végétaux (US Analyses), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Domaine expérimental de Melgueil (MONTP MELGUEIL UE), Institut National de la Recherche Agronomique (INRA), Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Ecole Nationale Forestière d'Ingénieurs du Maroc (ENFI), Analyses des eaux, sols et végétaux (Cirad-Persyst-US 49 Analyses), Département Performances des systèmes de production et de transformation tropicaux (Cirad-PERSYST), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), and Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
P33 - Chimie et physique du sol, METHODE D'ANALYSE, EROSION, SOL CULTIVE, SPECTROMETRIE INFRAROUGE, MINERALISATION, CARBONE ORGANIQUE, STOCK ORGANIQUE, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, ANALYSE SPECTRALE, VARIATION SPATIALE, CARBONATE, U30 - Méthodes de recherche, UTILISATION DU SOL, ZONE DE MONTAGNE
Abstract

Effective protection of environmental resources requires an understanding of spatial and temporalvariation of soil properties, and its causes and its consequences. However, the acquisition of data on thisvariability requires datasets whose achievement is limited by the cost of physico-chemical analyses, and also insome cases by the amount of material available. For studies related to carbon sequestration in soils and theirvulnerability to land use and climate changes, additional limitations appear in carbonate soils as organic formsand inorganic carbon must be distinguished. Assuming that the near-infrared spectroscopy (NIRS) could helpovercome these limitations, this paper presents some results obtained with NIRS through two examples ofstudies in carbonate environment, one in the watershed the Rheraya (High Atlas of Morocco) and the other inthe plain of Languedoc (France). These examples show that depending on the particular case studied andphysicochemical methods implemented a procedure for prediction by NIRS may be efficient to predict the Corgand inefficient for predicting carbonates or moderately efficient in predicting the Corg and very efficient to predictthe carbonates.; La protection efficace des ressources environnementales nécessite une bonne connaissancedes variations spatiales et temporelles des propriétés des sols, ainsi que de ses causes et de sesconséquences. Cependant, l'acquisition de données sur cette variabilité nécessite des jeux dedonnées dont l'obtention est limitée par le coût des analyses physico-chimiques, mais aussi, danscertains cas, par la quantité de matériau disponible. Pour les études liées à la séquestration ducarbone dans les sols et à leur vulnérabilité aux changements d’usage et aux changementsclimatiques, des limites supplémentaires apparaissent dans les sols carbonatés, car les formesorganiques et inorganiques du carbone doivent être distinguées. Partant de l’hypothèse que laspectroscopie proche infrarouge (SPIR) pourrait permettre de dépasser ces limites, cettecommunication présente quelques résultats obtenus avec la SPIR à travers deux exemples d'étudesen milieu agricole carbonaté, l’un dans le bassin versant de la Rhéraya (Haut-Atlas du Maroc) etl’autre dans la plaine languedocienne (France). Ces exemples montrent notamment que selon le casétudié et les méthodes physico-chimiques mises en œuvre, une procédure de prédiction par SPIRpeut être soit efficiente pour prédire le Corg et non efficiente pour prédire les carbonates, soitmoyennement efficiente pour prédire le Corg et très efficiente pour prédire les carbonates

Published
2011

46. Spéciation, mécanismes d’acquisition de la composition chimique des solutions du sol et modélisation des cycles biogéochimiques

Author

Gerard, Frederic, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Université Montpellier 2 (Sciences et Techniques), Doyle Mc Key, and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)

Subjects
Geochemistry, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Géochimie, hdr, cycle biogéochimique
Published
2008

48. The Peculiarities of Low-Cost Carrier Development in Europe

Author

Jolanta Sabaitytė, Vida Davidavičienė, and Gerard Frederick Van Kleef

Subjects
low-cost carrier, development, airline industry, airline issues, transport industry, industry growth, Technology
Abstract

Low-cost carriers (LCCs) have been growing by 11.4% in revenue passenger kilometers over 2017 and changed the airline industry radically. It drove down prices in the industry. Southwest Airlines (USA) designed the LCC blueprint model, and Ryanair copied it within Europe, followed by other airlines. This research aims to fulfill the gap in contemporary research upon LCC successfulness in Europe by a description of the current situation within Europe (2018 and January 2019) and the development issues it faced, which are mapped by the Ishikawa fishbone diagram. Furthermore, to rank the airlines on strength and vulnerability, The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) methodology was used for meeting LCC characteristics and airline success. By comparison of meeting the LCC characteristics and the rank of the successfulness, the results of the TOPSIS analysis showed that the airlines meeting the most LCCs characteristics are seemingly less vulnerable to the development issues that airlines are facing, as Wizz Air and Ryanair are meeting most characteristics and are the most successful. Concluded is that airlines meeting the most LCC characteristics are the least vulnerable to current issues. However, major disruptions can still form an issue and limit growth. This research can be useful for comparing and positioning airlines in the market, based on issues and operational choices.

Published
2020
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49. Frederic Francis Gerard's letters to his daughters

Author

Gerard, Frederic Francis, 1829-1913 and Gerard, Frederic Francis, 1829-1913

Abstract

A series of four letters written by Frederic Francis Gerard to his four daughters. Gerard talks about General Custer and the Battle of the Little Bighorn, admonishes them for their homesickness at boarding school, chides them into doing their homework, and about a life insurance policy. He also mentions Father De Smet, and writes in the 1883 letter to his daughter Virginia about her taking her vows as a nun.

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