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1. What is the influence of anthropogenic impact on the population structure of Attalea speciosa Mart. ex Spreng. in the Brazilian Amazonian region?

Author: Alessio Moreira dos Santos, Danielle Mitja, Izildinha de Souza Miranda, Patrice Loisel, Eric Delaître, and Laurent Demagistri
Subjects: Amazon, Attalea speciosa, population structure, anthropogenic impact, Botany, QK1-989
Abstract: ABSTRACT Attalea speciosa (babassu) is a native palm of the primary forest from Amazonian and Cerrado biomes, and has multiple economic and cultural uses. However, this palm can become dominant in open areas, with a long-term persistence in the community. The objective of this study was to compare the population structure and morphology of babassu in three habitat types characterizing forest succession: primary forest, pasture, and babaçual (babassu-dominated secondary forest). For this purpose, we monitored 6,333 individuals for three years at six life stages in 11 sites with 25 plots located in PA-Benfica, Itupiranga-Pará, Brazil. The morphological parameters showed differences between secondary environments (pasture and babaçual) and primary forests, suggesting that this species has a high capacity for phenotypic plasticity. The inverse J-shaped distribution was observed only in primary forests, with the density of all stages constant along the whole study, unlike pastures and babaçual areas. While the density of seedlings is highest in primary forests, stage 4 and 5 juveniles and adults are most numerous in babaçuals. Our results suggest that the higher dominance of A. speciosa in babaçual areas can be associated with the resilience of this species to anthropogenic disturbances.
Published: 2022
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2. Faut-il s’intéresser à la petite et moyenne forêt privée française ?

Author: Bernard Elyakime, Alain Cabanettes, and Patrice Loisel
Subjects: Forestry, SD1-669.5
Abstract: Devant l’importance de la forêt française et des secteurs de la transformation des bois en France, la gestion des interfaces société-forêt-industrie du bois est essentielle. Après avoir décrit cette gestion et précisé ses difficultés, un nouveau projet de gestion de ces interfaces, issu du Gouvernement français, est présenté. Ce projet de régulation en économie forestière s’intéresse aux rapports économiques entre les acteurs forestiers ou industriels et les acteurs publics. Ce projet engagerait l’État sur un vigoureux interventionnisme industriel en première transformation des bois, en s’intéressant à sa modernisation, à sa pérennisation par sa diversification, son intégration vers la seconde transformation mais aussi à l’extension de son approvisionnement en bois. Il chercherait à diversifier et intensifier les modes de vente des bois aux industriels du bois. Cet interventionnisme économique offensif pourrait cependant se dérouler sans avoir auparavant ou parallèlement assuré les conditions d’un développement spécifique des petites et moyennes propriétés forestières de moins de 25 ha, à moins que d’autres conditions de régulation du développement de la forêt privée ne soient aussi mises en place.
Published: 2015
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3. Private environmental incentive contract and a weather signal

Author: Patrice Loisel and Bernard Elyakime
Subjects: Environmental sciences, GE1-350
Published: 2011

4. A filter-based approach for global sensitivity analysis of models with functional inputs.

Author: Sébastien Roux, Patrice Loisel, and Samuel Buis
Published: 2019
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5. A numerical distance based on fuzzy partitions.

Author: Serge Guillaume, Brigitte Charnomordic, and Patrice Loisel
Published: 2011
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6. Fuzzy partitions: A way to integrate expert knowledge into distance calculations.

Author: Serge Guillaume, Brigitte Charnomordic, and Patrice Loisel
Published: 2013
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7. Which early indicator allows for a better understanding of the evolution of the COVID-19 epidemic in France?

Author: Patrice Loisel
Subjects: Coronavirus disease 2019 (COVID-19), business.industry, Disease, Intensive care unit, Asymptomatic, law.invention, law, Intensive care, Medicine, Detection rate, medicine.symptom, business, Relevant information, Demography
Abstract: We provide an explanation for the apparent discrepancy between the dynamic of the positive COVID-19 test rates and of the numbers of COVID-19-related hospital and intensive care admissions and deaths in France. We highlight the existence of a latency period of around 5 weeks between the infections of young individual (generally asymptomatic) to older individuals that may have a severe form of the disease and may be hospitalized. If the overall positive detection rate provided relevant information until the end of August, since the beginning of September the overall positive detection rate has reached a plateau and no longer provides relevant information on the current state of the epidemic. We show that the positive detection rate in the 70+ age group is a relevant and early indicator of the epidemic. Furthermore, we have shown an identical doubling time of around 16 days for the following indicators: the positive tests rate for the 70+ age group, the number of new admissions to hospital, intensive care unit admissions and deaths.
Published: 2020
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8. Under the risk of destructive event, are there differences between timber income based and carbon sequestration based silviculture?

Author: Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), 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)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Subjects: Carbon sequestration, Economics and Econometrics, Sociology and Political Science, [SDV]Life Sciences [q-bio], 0211 other engineering and technologies, 02 engineering and technology, 010501 environmental sciences, Management, Monitoring, Policy and Law, 01 natural sciences, Tipping age, Statistics, Silviculture, 0105 earth and related environmental sciences, Risk adjusted, Event (probability theory), Faustmann value, 021107 urban & regional planning, Forestry, 15. Life on land, Optimal control, 13. Climate action, Optimal trajectory, Environmental science, Very high risk, Calculus of variations
Abstract: International audience; We consider the management of a mono-specific even-aged forest at the stand level. Optimal silviculture based on timber income and sequestered carbon income in an no risk case and a risky case are compared. In this study, using calculus of variations we discuss the validity of using a risk adjusted discount rate (a rate of natural risk added to the discount rate) or using a carbon adjusted discount rate (a rate of natural risk subtracted to the carbon discount rate) without risk to mimic the natural risk case in term of optimal thinnings. Except for very high risk rate values in the risky case, the optimal trajectory for carbon sequestration is very different from that obtained for the timber criterion. We show that without risk or with risk case but moderate risk rate, the optimal cutting age for sequestered carbon will be the senescence age. For higher risk rate the optimal cutting age for sequestered carbon may be more comparable to optimal timber cutting age.
Published: 2020
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9. Stochastic perturbations and fisheries management

Author: Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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 Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)
Subjects: Mathematical optimization, Environmental Science (miscellaneous), [QFIN.RM]Quantitative Finance [q-fin]/Risk Management [q-fin.RM], Piecewise Deterministic Markov Process (PDMP), FOS: Economics and business, 03 medical and health sciences, optimal control, Order (exchange), Bellman equation, 0502 economics and business, FOS: Mathematics, 14. Life underwater, Piecewise-deterministic Markov process, Mathematics - Optimization and Control, 030304 developmental biology, Mathematics, 0303 health sciences, Probability (math.PR), 05 social sciences, Optimal control, Natural resource, [SDE.ES]Environmental Sciences/Environmental and Society, Dynamic programming, value function, [MATH.MATH-PR]Mathematics [math]/Probability [math.PR], Optimization and Control (math.OC), Risk Management (q-fin.RM), Modeling and Simulation, Jump, 050202 agricultural economics & policy, Fisheries management, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], Mathematics - Probability, Quantitative Finance - Risk Management
Abstract: As most natural resources, fisheries are affected by random disturbances. The evolution of such resources may be modelled by a succession of deterministic process and random perturbations on biomass and/or growth rate at random times. We analyze the impact of the characteristics of the perturbations on the management of natural resources. We highlight the importance of using a dynamic programming approach in order to completely characterize the optimal solution, we also present the properties of the controlled model and give the behavior of the optimal harvest for specific jump kernels., Natural Resource Modeling, Wiley, In press
Published: 2019

10. Coviability of social and ecological systems : reconnecting mankind to the biosphere in an era of global change. Vol. 2 : Coviability questioned by a diversity of situations

Author: Eric Delaître, Deiane Jorge Macedo, Izildinha Souza Miranda, Laurent Demagistri, Bénédicte Fontez, Nikolay Sirakov, Hélène Rey-Valette, Maria Regina Teixeira da Rocha, Patrice Loisel, Danielle Mitja, Thérèse Libourel, Sol González-Pérez, Alessio Moreira dos Santos, Institut de Recherche pour le Développement (IRD), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Universidade Federal do Sul e Sudeste do Para (UNIFESSPA), Universidade Federal Rural da Amazônia (UFRA), Universidade Federal do Pará (UFPA), Centre d'Economie de l'Environnement - Montpellier - FRE2010 (CEE-M), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Université de Montpellier (UM), the Foundation Agropolis Open Science program (project sustainable management of the babassu palm, 2014-2017) and the CNES TOSCA program (project CIC-TOOB 2013-2014), Barrière, Olivier (ed.), Behnassi, M. (ed.), David, Gilbert (ed.), Douzal, V. (ed.), Fargette, Mireille (ed.), Libourel, T. (ed.), Loireau, Maud (ed.), Pascal, L. (ed.), Prost, C. (ed.), Ravena Canete, V. (ed.), Seyler, Frédérique (ed.), Morand, S. (ed.), 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 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 de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), 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)
Subjects: 0106 biological sciences, [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, eco-socio-system, écosociosystème, télédétection, Population, 010501 environmental sciences, 010603 evolutionary biology, 01 natural sciences, Amazonian rainforest, remote sensing, Attalea speciosa, education, uses, 0105 earth and related environmental sciences, education.field_of_study, babaçu, [SHS.SOCIO]Humanities and Social Sciences/Sociology, [SHS.STAT]Humanities and Social Sciences/Methods and statistics, biology, Land use, babassu, Agroforestry, 15. Life on land, biology.organism_classification, Tree (data structure), Geography, dynamique de population, [SHS.ENVIR]Humanities and Social Sciences/Environmental studies, Sustainability, extractivism, dynamics of the population, extractivisme, usages, Palm, Forage crop
Abstract: Vol. 2: Coviability Questioned by a Diversity of Situations Chapitre 40 La version en français sera publiée ultérieurement aux éditions Matériologiques en co-édition avec les éditions IRD; International audience; The babassu palm tree (Attalea speciosa Mart. ex Spreng.) is a species native to the Amazonian rainforest. The invasive nature of this palm tree results in a high density of babassu palm trees with a subsequent decrease in forage crop production. This is a serious problem for local farmers who have tried to resolve it by removing mature palms, seedlings and young individuals. Within these conditions, is coviability between the babassu palm tree and society possible? Our work consisted in developing tools and methods with the aim of producing knowledge and providing answers to this issue within a given territory. To understand the eco-socio-system, we have explored the available knowledge in the literature, produced specific field data, tools and methods such as mathematical modeling (dynamics of the palm tree population) and remote sensing (land use analysis thanks to Landsat high-resolution images and automatic detection of mature palm trees using Pleiades and GeoEye very high-resolution images). This multidisciplinary research in progress has already given us a good overview of the current situation of this eco-socio-system, enabling us to consider the best way to ensure its sustainability.
Published: 2019
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11. An optimisation-based approach to generate interpretable within-field zones

Author: Hazaël Jones, Brigitte Charnomordic, Patrice Loisel, Bruno Tisseyre, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), 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 de la Recherche Agronomique (INRA), Information – Technologies – Analyse Environnementale – Procédés Agricoles (UMR ITAP), Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-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: MANAGEMENT CLASSES, Decision support system, Computer science, 0211 other engineering and technologies, 04 agricultural and veterinary sciences, 02 engineering and technology, computer.software_genre, Plot (graphics), Field (computer science), Set (abstract data type), Complementarity (molecular biology), [SDE]Environmental Sciences, 040103 agronomy & agriculture, CONTRAST INDICATOR, 0401 agriculture, forestry, and fisheries, sort, Data mining, General Agricultural and Biological Sciences, Zoning, computer, ZONING CRITERIA, 021101 geological & geomatics engineering, Quantile
Abstract: International audience; The paper proposes a numerical criterion to evaluate zoning quality for a given number of classes. The originality of the criterion is to simultaneously quantify how zones are heterogeneous on the whole field under study and how neighbouring zones are similar. This approach allows comparison between maps either with different zones or different labels, which is of importance for zone delineation algorithms aiming at maximizing inter-zone variability. In addition, this study also proposes an optimisation procedure that yields interpretable within-field zones in which each zone is assigned a clear label. The zoning procedure involves contour delineation based on quantile values. The key point of the paper is to use the proposed numerical zoning quality criterion to guide the optimisation procedure showing the complementarity of both proposals in delineating relevant within-field zones. In order to demonstrate the relevancy of the criterion, the zoning procedure and the implementation of both together, the method was tested on 50 theoretical fields with known variability and known spatial structure. A real plot with yield monitoring data was also used to demonstrate the value of the approach on a real case. Results show the relevancy of the methodology to compare maps with different zones and to sort them. Results also demonstrate the interest of the optimisation procedure to provide a ranked set of possible maps with different within-field zones. This set of relevant maps may constitute a decision support for practitioners who may consider additional expert information to choose the most appropriate map in the specific conditions under consideration.
Published: 2019
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12. Incentives under Upstream-Downstream Moral Hazard Contract

Author: Bernard Elyakime, Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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), Laboratoire d'Economie Forestière (LEF), Ecole Nationale du Génie Rural, des Eaux et des Forêts (ENGREF)-Institut National de la Recherche Agronomique (INRA), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), and AgroParisTech-Institut National de la Recherche Agronomique (INRA)
Subjects: Statistics and Probability, Economics and Econometrics, Moral hazard, media_common.quotation_subject, partnership, environmental good, public environmental policy, spatialized contract, ancillary statistics, bunching, [SHS]Humanities and Social Sciences, Microeconomics, Downstream (manufacturing), [INFO]Computer Science [cs], [MATH]Mathematics [math], health care economics and organizations, media_common, Upstream (petroleum industry), Environmental good, JEL: D - Microeconomics/D.D8 - Information, Knowledge, and Uncertainty, Public good, Payment, [SHS.ECO]Humanities and Social Sciences/Economics and Finance, JEL: Q - Agricultural and Natural Resource Economics • Environmental and Ecological Economics/Q.Q5 - Environmental Economics, Incentive, Order (business), Business, Statistics, Probability and Uncertainty, Spatialized contract, Social Sciences (miscellaneous)
Abstract: Cet article étudie les caractéristiques d’un contrat de production d’un bien public environnemental avec aléa moral entre deux producteurs privés initialement non-associés mais dépendants par un flux physique, l’un étant en amont de l’autre. La performance de la fonction de paiement est étudiée en détail, afin de clarifier la façon dont le contrat avec aléa moral fonctionne. Après avoir présenté et calculé le contrat nous déduisons les fonctions de paiement non-linéaires incitatives. Les résultats du producteur en aval dépendent du résultat du producteur en amont. Les fonctions de paiement héritent donc de cette structure de dépendance : le paiement du producteur en amont ne dépend que de ses résultats alors que le paiement du producteur en aval dépend de ses propres résultats ainsi que de ceux du producteur en amont. Dans certains cas, le comportement de la fonction de paiement aval peut entraîner sa non-acceptabilité par les contractants. Pour y remédier nous proposons l’adjonction d’une contrainte d’acceptabilité : un bunching d’un nouveau type apparaît pour le paiement du producteur aval., This paper explores the characteristics of an upstream-downstream moral hazard contract between two private initially non-associated producers in a spatialized and flow dependence, one upstream of the other, to provide an environmental public good. The performance of the payment function is studied in detail, in order to clarify how the moral hazard contract operates. After having drawn up and calculated the contract, we derive the incentive non-linear payment functions. The results of the downstream producer depend on the result of the upstream producer. Payments producers thus inherit this dependency structure : payment for the upstream contractor only depends on his results whereas payment for the downstream contractor depends on his own results and on those of the upstream contractor. In some cases, the behavior of the downstream payment function can lead to a possible non-acceptability of the payment function by contractors. To remedy the situation we add an acceptability constraint : a new type of bunching appears for the payment of the downstream producer.
Published: 2019
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13. A stage-structured hierarchical Bayes model for the babassu palm tree population dynamics – Estimated from anthropogenic open area data sets

Author: Patrice Loisel, Danielle Mitja, Bénédicte Fontez, Alessio Moreira dos Santos, Thérèse Libourel, Nikolay Sirakov, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), UMR 228 Espace-Dev, Espace pour le développement, Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM)-Université de Guyane (UG)-Université des Antilles (UA), Université de Montpellier (UM), SARH – Instituto Ambiental e de Recursos Hídricos, Universidade Federal Rural da Amazônia (UFRA), This research work has been accomplished as a part of the Open Science research project (under the reference ID 1403-026) financed by the Agropolis Foundation and by the French National Institute of Agronomical Research (INRA) and 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 de la Recherche Agronomique (INRA), Université de Guyane (UG)-Université des Antilles (UA)-Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), and Université des Antilles (UA)-Université de Guyane (UG)-Université de Montpellier (UM)-Université de La Réunion (UR)-Avignon Université (AU)-Université de Perpignan Via Domitia (UPVD)-Institut de Recherche pour le Développement (IRD)
Subjects: 0106 biological sciences, Population dynamics, Population, Bayesian statistics, palmier, 010603 evolutionary biology, 01 natural sciences, Bottleneck, Bayes' theorem, modèle mathématique, Deforestation, [MATH.MATH-ST]Mathematics [math]/Statistics [math.ST], Attalea speciosa, population dynamics, mathematical modelling, education, estimation statistique, education.field_of_study, Mathematical modelling, biology, Amazon rainforest, Agroforestry, 010604 marine biology & hydrobiology, Ecological Modeling, 15. Life on land, biology.organism_classification, modèle bayésien, Tree (data structure), statistical estimation, dynamique des populations, Geography, palm tree, Babassu palm tree, mathematical model
Abstract: The babassu palm tree (Attalea speciosa Mart. ex Spreng.) is an endemic species of Amazon forests, and has social and economical impact/utility. Deforestation highlights this palm tree in anthropogenic open areas (pastures and cultivated fields). Simultaneously, knowledge concerning the sustainable functioning of the species within these manmade environments is sorely lacking: its life cycle is not well known, and its population dynamics remains unstudied. In this study, our objective was to generate a model of the population dynamics of the babassu palm tree, validated by in situ analysis, to understand how babassu, a forest species, adapts to pastureland and, under certain conditions, becomes invasive. We propose a random matrix model with aggregated variables based on the biological stages of the species as the input. The probabilities of the between-stage transition matrix were modelled using a Dirichlet-multinomial model with a hierarchy taking geographical organization, i.e. transect level, into account. The integration of prior information was formulated through a Bayesian approach. This Bayesian hierarchical matrix model enabled us to demonstrate a bottleneck in the population dynamics and a high year-dependent mortality rate at an early stage.
Published: 2019
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14. Insurance and forest rotation decisions under storm risk

Author: Stéphane Couture, Marielle Brunette, Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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), Bureau d'Économie Théorique et Appliquée (BETA), Université de Lorraine (UL)-Université de Strasbourg (UNISTRA)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS), Unité de Mathématiques et Informatique Appliquées de Toulouse (MIAT INRA), Institut National de la Recherche Agronomique (INRA), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), 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 de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Strasbourg (UNISTRA)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), université dauphine, Climate Economics Chair, Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), ANR-11-LABX-0002,ARBRE,Recherches Avancées sur l'Arbre et les Ecosytèmes Forestiers(2011), and Institut National de la Recherche Agronomique (INRA)-Université de Strasbourg (UNISTRA)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Economics and Econometrics, subsidy, 020209 energy, media_common.quotation_subject, Forest management, Climate change, Context (language use), 02 engineering and technology, Management, Monitoring, Policy and Law, [QFIN.RM]Quantitative Finance [q-fin]/Risk Management [q-fin.RM], JEL: G - Financial Economics/G.G2 - Financial Institutions and Services/G.G2.G22 - Insurance • Insurance Companies • Actuarial Studies, [SHS]Humanities and Social Sciences, Faustmann Value, insurance, risk-sharing, storm risk, rotation length, Insurance policy, 0502 economics and business, 0202 electrical engineering, electronic engineering, information engineering, Risque d'orage, [INFO]Computer Science [cs], 050207 economics, [MATH]Mathematics [math], ComputingMilieux_MISCELLANEOUS, media_common, Actuarial science, [QFIN]Quantitative Finance [q-fin], Risk aversion, 05 social sciences, Assurance, Storm, JEL: D - Microeconomics/D.D8 - Information, Knowledge, and Uncertainty/D.D8.D81 - Criteria for Decision-Making under Risk and Uncertainty, Public transfer, 15. Life on land, [SHS.ECO]Humanities and Social Sciences/Economics and Finance, JEL: Q - Agricultural and Natural Resource Economics • Environmental and Ecological Economics/Q.Q2 - Renewable Resources and Conservation/Q.Q2.Q23 - Forestry, 13. Climate action, Partage des risques, Insurance · Storm risk, Psychological resilience, Business, Insurance coverage
Abstract: International audience; Forests are often threatened by storms; and such a threat is likely to increase due to climate change. Indeed, climate change is expected to increase the frequency and intensity of extreme events such as intensive storms. For forest owners, adaptation to climate change will require major adjustments in forest management practices. Then, forest owners will have to take these increasing risks into account through risk-sharing (insurance) and risk-reducing strategies (reduction of rotation length). In this paper, we propose to jointly analyze the forest owner’s insurance decision and the rotation age under storm risk. We extend the Faustmann optimal rotation model under risk, first, considering the forest owner’s preferences towards risk, and second, integrating the decision of insurance. With this analytical model, we show that unless the forest owner’s discount rate and the insurer’s discount rate are sufficiently unequal, it is not optimal for the forest owner to adopt insurance. We prove that the rotation length increases as the insurance premium increases, i.e. substitution between the two coverage mechanisms. Finally, we discuss the potential implications of government policy on the insurance scheme.
Published: 2018
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15. The declining price anomaly in sequential auctions of identical commodities with asymmetric bidders: empirical evidence from the Nephrops norvegicus market in France

Author: Patrice Loisel, Frédéric Salladarré, Patrice Guillotreau, Pierrick Ollivier, Institut Universitaire de Technologie de Rennes (IUT de Rennes), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Centre de recherche en économie et management (CREM), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'économie et de management de Nantes Atlantique (LEMNA), FR 3473 Institut universitaire Mer et Littoral (IUML), Université de Bretagne Sud (UBS)-Le Mans Université (UM)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Le Mans Université (UM)-Université d'Angers (UA)-Centre National de la Recherche Scientifique (CNRS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Institut d'Économie et de Management de Nantes - Institut d'Administration des Entreprises - Nantes (IEMN-IAE Nantes), Université de Nantes (UN)-Université de Nantes (UN), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut d'Économie et de Management de Nantes - Institut d'Administration des Entreprises - Nantes (IEMN-IAE Nantes), Université de Nantes (UN)-Université de Nantes (UN)-FR 3473 Institut universitaire Mer et Littoral (IUML), Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Institut Universitaire de Technologie - Rennes (IUT Rennes), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Économie et de Management de Nantes - Institut d'Administration des Entreprises - Nantes (IEMN-IAE Nantes), 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), Coselmar research project - Regional Council of Pays de la Loire, École Centrale de Nantes (ECN)-Université de Nantes (UN)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Le Mans Université (UM)-Université de Bretagne Sud (UBS)-École Centrale de Nantes (ECN)-Université de Nantes (UN)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université d'Angers (UA)-Le Mans Université (UM)-Université de Bretagne Sud (UBS), Université de Rennes (UR), Normandie Université (NU)-Normandie Université (NU)-Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM)-Université d'Angers (UA)-Université de Nantes (UN)-École Centrale de Nantes (ECN)-Université de Bretagne Sud (UBS)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), and Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)
Subjects: Economics and Econometrics, Auction theory, auction, Risk premium, Supply and demand, Microeconomics, norvège, 0502 economics and business, Econometrics, Economics, Market price, Common value auction, 050207 economics, homarus, ComputingMilieux_MISCELLANEOUS, 050205 econometrics, price control, Stylized fact, 05 social sciences, [SHS.ECO]Humanities and Social Sciences/Economics and Finance, Value (economics), seafood market, contrôle des prix, Agronomy and Crop Science, france, Panel data, declining price anomaly
Abstract: International audience; The declining price anomaly for sequential sales of identical commodities challenges auction theory which predicts constant prices within a day. Among other hypotheses explaining the phenomenon stands the dual value of goods including a risk premium in early transactions. We consider that asymmetric bidder groups (primary processors, fishmongers, supermarket buyers) and seasonal landings may also affect the daily price pattern. On the basis of stylized facts and several panel data models, this hypothesis is tested on a Redundant French fish market of homogenous goods (live Nephrops norvegicus) when the time effects (high and low seasons, weekday effect) affecting the demand and supply conditions are taken into consideration. All models support the evidence of a daily declining pattern, but not to the same extent for all days and seasons, and all categories of buyers. Our results also show an earlier and steeper decline on periods of lower supply (or higher demand), supporting the theoretical hypothesis of risk-averse behaviors of bidders, especially fishmongers with respect to primary processors and supermarkets.
Published: 2017
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16. The Faustmann model under storm risk and price uncertainty: A case study of European beech in Northwestern France

Author: Hanitra Rakotoarison, Patrice Loisel, ONF, RDI department, Office National des Forêts (ONF), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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), Economic, Human and Social Science Researchers Network of Ecofor : ECOFOR 2012-24, and Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)
Subjects: Economics and Econometrics, 010504 meteorology & atmospheric sciences, Sociology and Political Science, Natural resource economics, Forest management, gestion prévisionnelle, Management, Monitoring, Policy and Law, 01 natural sciences, forest, Fagus sylvatica, Environmental protection, forêt, Economics, Wood industry, Beech, 0105 earth and related environmental sciences, 040101 forestry, wood industry, biology, modèle économique, Global warming, storm damage, risk assessment, Forestry, Storm, 04 agricultural and veterinary sciences, forest policy, 15. Life on land, biology.organism_classification, Natural resource, price uncertainty, 13. Climate action, 0401 agriculture, forestry, and fisheries, Economic model, gestion des forêts, forecasting management, France, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], évaluation des risques, risks, outil d'aide à la décision, economic model
Abstract: International, economic and environmental contexts in this century are strongly affected by risks and uncertainties. Due to the long-term nature of forest investment, forest managers must integrate risks and uncertainties into their decisions. Our objective is to build a decision support tool to optimize forest management under multiple risks: extreme events and price variations. Our method integrates, into an economic model, different types of models on forest growth, price functions, predicted storm intensity and intervals, and damage functions. A numerical simulation applied to European beech (Fagus sylvatica) in Northwestern France shows that price variation as between 1974 and 2016 produces higher economic loss than does storm damage. We conclude on the need to concentrate forest policy on the development of new technologies and wood industry practices to increase the value of this natural resource. However, future climate change may well influence storm frequency and intensity, and this places limits on our conclusions.
Published: 2017
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17. A filter-based approach for global sensitivity analysis of models with functional inputs

Author: Sébastien Roux, Samuel Buis, Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), 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 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), Université de la Réunion. Le Tampon, REU., French National Institute for Agricultural Research (INRA), and ProdInra, Migration
Subjects: Computer science, 0211 other engineering and technologies, 02 engineering and technology, Type (model theory), Signal, Industrial and Manufacturing Engineering, modèle mathématique, Global sensitivity analysis, Crop model, Safety, Risk, Reliability and Quality, 021110 strategic, defence & security studies, 021103 operations research, Toy model, Building energy, Sobol sequence, Filter (signal processing), Modélisation et simulation, simulation, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Sobol’ indices, Switching variables, Boolean factors, Filtering error, Climatic inputs, mathématiques appliquées, Modeling and Simulation, [INFO.INFO-MO] Computer Science [cs]/Modeling and Simulation, Algorithm, Smoothing
Abstract: 8. International Conference on Sensitivity Analysis of Model Output (SAMO); International audience; We design a method called filter-based global sensitivity analysis (filterbased GSA) to analyze computer models with functional inputs. Understanding the impact of functional inputs is central in many applications like building energy or environmental studies. The present work is a step further in the analysis of the impact of functional inputs signal components on to model responses of interest. To perform filter-based GSA, the functional inputs are modified with filters in order to either enhance or suppress some components in the signal. The influence of filters on the model response is assessed by computing the Sobol’ indices of Boolean factors that trigger the filters application. Two relationships between these indices and the error resulting from the filters application are established. The method is illustrated with smoothing filters applied on the climatic inputs of a toy model simulating crop yield. We show that the high frequencies for three out of the four climatic inputs are not important in the tested configuration. The present method does not require any hypotheses on the model or the type of filters used. It seems promising for model understanding, validation or simplification.
Published: 2016
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18. Bayesian hierarchical modeling: application to the babassu palm tree population dynamics in Brazil

Author: Nikolay Sirakov, Patrice Loisel, Bénédicte Fontez Nguyen The, Danielle Mitja, Thérèse Libourel Rouge, Alessio dos Santos Moreira, Izildinha Miranda, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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 de Recherche pour le Développement (IRD), Universidade Federal Rural da Amazônia (UFRA), 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)-Institut National de la Recherche Agronomique (INRA)
Subjects: population dynamics, babassu palm tree, bayesian modeling, [INFO]Computer Science [cs], [MATH]Mathematics [math]
Abstract: International audience; The babassu palm tree (Attalea speciosa Mart. ex Spreng.) is an endemic species of the amazonian forests. For decades, the progress of the pioneer front highlights this palm tree in the anthropogenic open areas: pastures and cultivated fields. The babassu is one of the "extractive" resources in Brazil: gathering activity followed by marketing of non-timber products. This activity involves people among the most disadvantaged in the country. Despite this fact, the knowledge of long term functioning of the palm tree is sorely lacking. Our goal is to understand its population dynamics in the pastures and to guide local populations towards a sustainable management of the species. Our modelization process is based on field data series collected between 2013 and 2015. This field research work was conducted in situ in the community of Benefica, state of Para, Brazil. First we selected transects inside pastures randomly, then we counted systematically all the individuals inside those transects. We had analyzed the babassu life cycle and we decided to modelize each one of the three major biological processes: mortality, growth and recruitment. We actually develop a multinomial hierarchical model approach which relies on aggregated data: sum of the individuals per stage and per transect. In this talk we present a Bayesian modeling framework analysis with MCMC algorithms for estimate mortality, growth and recruitment rates. Mortality and growth rates are estimated for all six biological stages. We detect and highlight a critical transition between stages 3 and 4. Biologicaly this transition corresponds to the transfer of the bud from the soil to the surface. The vulnerability of babassu thus increases enormously. Our results also underline differences between transects - important location variability.
Published: 2016

19. Incitation salariale et groupement d'employeurs

Author: Bernard Elyakime, Patrice Loisel, ProdInra, Migration, Unité d'économie et sociologie rurales de Toulouse, Institut National de la Recherche Agronomique (INRA), Analyse des Systèmes et Biométrie (ASB), Rapaport, Alain, and Station d'économie et sociologie rurales
Subjects: INCITATION SALARIALE, jel:D70, jel:D81, [INFO.INFO-OH]Computer Science [cs]/Other [cs.OH], CONTRAT INCITATIF, GROUPEMENT D'EMPLOYEURS, [MATH] Mathematics [math], SCIENCE ECONOMIQUE, [INFO] Computer Science [cs], [SHS.ECO]Humanities and Social Sciences/Economics and Finance, jel:J20, jel:J31, jel:J21, [SHS]Humanities and Social Sciences, [INFO.INFO-OH] Computer Science [cs]/Other [cs.OH], [INFO]Computer Science [cs], [SHS] Humanities and Social Sciences, [MATH]Mathematics [math], [SHS.ECO] Humanities and Social Sciences/Economics and Finance, General Economics, Econometrics and Finance
Abstract: Codes JEL : D70 ; D81 ; J20 ; J21 ; J31; Face à la montée du salariat à temps partiel notamment dans les groupements d’employeurs agricoles, nous étudions cette structure afin de rendre plus attractif l’emploi salarié dans un groupement d’employeurs : paiement incitatif des salariés et conditions de son existence. Chaque membre au sein du groupement d’employeurs a sa pondération exogène qui est un paramètre important car il conditionne tant les revenus des membres du groupement que les paiements que ceux-ci donnent au salarié. Il apparaît aussi, en cas d’effort salarial (observable ou non) identique selon les employeurs, qu’il existe une condition suffisante pour qu’un paiement incitatif existe. Le contrat incitatif en cas d’effort salarial (observable ou non) différencié par employeur existe par contre sans condition particulière.
Published: 2008
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20. Coordination, independence or synchronization of individual vigilance in the eastern grey kangaroo?

Author: Patrice Loisel, Olivier Pays, Jean-François Gerard, Peter J. Jarman, Unité de recherche Comportement et Ecologie de la Faune Sauvage (CEFS), Institut National de la Recherche Agronomique (INRA), Communauté de Communes de l'Agglomération Annemessienne, Partenaires INRAE, University of New England (UNE), and Analyse des Systèmes et Biométrie (ASB)
Subjects: 0106 biological sciences, MACROPUS GIGANTEUS, media_common.quotation_subject, GROUP SIZE, ETHOLOGIE, Biology, Group living, 010603 evolutionary biology, 01 natural sciences, Synchronization, 0501 psychology and cognitive sciences, 050102 behavioral science & comparative psychology, Ecology, Evolution, Behavior and Systematics, media_common, 05 social sciences, Independence, EASTERN GREY KANGAROO, ALLELOMIMESIS, SCANNING, [SDV.SA.SPA]Life Sciences [q-bio]/Agricultural sciences/Animal production studies, Allelomimetic behavior, Animal Science and Zoology, COLLECTIVE BEHAVIOUR, Social psychology, Demography, Vigilance (psychology)
Abstract: International audience; Vigilance activity is usually considered an adaptive advantage of group living conferring protection against predators. An individual of a prey species is assumed to benefit from an increase in the number of group members by reducing its own investment in vigilance. However, the proximate mechanism generating the decrease in vigilance with increasing group size is unclear. Most models of this relation assume that either individuals coordinate their scans in nonoverlapping bouts of vigilance or animals scan independently of one another.We studied the relation between vigilance and group size in the eastern grey kangaroo, Macropus giganteus, analysing vigilance at two structural levels, individual vigilance and collective vigilance of the group. We tested both assumptions, coordination and independence of scanning. The time that an individual spent vigilant decreased with group size. However, the time during which at least one individual in the group scanned the environment (collective vigilance) increased up to a group size of seven individuals but decreased thereafter. Analyses revealed that individuals neither coordinated their scanning in an asynchronous way nor scanned independently of one another. On the contrary, both the onset and the end of individuals’ scanning bouts were synchronized between group members, producing waves of collective vigilance. Bouts of vigilance and nonvigilance activity tended to be synchronized. Our results appear to support a hypothesis of allelomimetic vigilance
Published: 2007
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21. An optimal standing timber auction?

Author: Patrice Loisel and Bernhard Elyakime
Subjects: Stumpage, Ecology, Geography, Planning and Development, Economics, Econometrics and Finance (miscellaneous), TheoryofComputation_GENERAL, Forestry, Microeconomics, Reservation price, Value (economics), Economics, ComputingMilieux_COMPUTERSANDSOCIETY, Common value auction, Timber volume, Lump sum
Abstract: We focus our study on a lump sum stumpage auction, with bids in total value and secret seller's reserve value. We check that the procedure examined may be ruled by a procedure dealing with total value but in which the seller would disclose his reserve strategic value. Moreover, the procedure with total value and disclosed seller's reserve strategic value may be ruled or not by a procedure on price (not on total value) and public seller's reserve price, in which buyers and seller would use the same real reference of the timber volume of the lot disclosed before the auction.
Published: 2005
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22. Un modèle d'enchères de bois sur pied

Author: Bernard Elyakime and Patrice Loisel
Subjects: TheoryofComputation_MISCELLANEOUS, ComputingMilieux_COMPUTERSANDSOCIETY, TheoryofComputation_GENERAL, Business and International Management, General Economics, Econometrics and Finance
Abstract: Modelling Standing Timber Auctions by Bernard Elyakime and Patrice Loisel In France, standing timber is often sold by auction with a secret reservation price and vaguely defined quantities. We propose two models in which there is an independent private value and different buyers' and sellers' estimates of quantities: one with a known reservation price and then one with a secret reservation price. We study the buyers' and sellers' strategies for working out the seller's expected revenues with and without a secret reserve price. The seller does better in an auction with a secret reservation price under certain market conditions., Un modèle d'enchères de bois sur pied par Bernard Elyakime et Patrice Loisel Les bois sur pied sont souvent vendus en France par enchères avec prix de retrait secret dans lesquelles le produit est mal défini quant à son volume. Nous étudions un modèle en valeur privée indépendante avec un volume de bois estimé différemment par les acheteurs et le vendeur, en prix de retrait public puis secret. Nous déterminons les stratégies des acheteurs et vendeur pour calculer l'espérance d'utilité du vendeur dans chacun des modèles. Celle du modèle à prix de retrait secret est alors supérieure à celle du modèle à prix de retrait public sous certaines conditions de marché., Elyakime Bernard, Loisel Patrice. Un modèle d'enchères de bois sur pied. In: Économie & prévision, n°132-133, 1998-1-2. pp. 93-101.
Published: 1998
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23. Impact of storm risk on Faustmann rotation

Author: Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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), ProdInra, Migration, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), 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)-Institut National de la Recherche Agronomique (INRA)
Subjects: Optimization, Economics and Econometrics, 010504 meteorology & atmospheric sciences, Sociology and Political Science, Yield (finance), animal diseases, Forest management, FOS: Physical sciences, Management, Monitoring, Policy and Law, [QFIN.RM]Quantitative Finance [q-fin]/Risk Management [q-fin.RM], 01 natural sciences, Cutting age, Economics, Econometrics, [QFIN.RM] Quantitative Finance [q-fin]/Risk Management [q-fin.RM], Operations management, Silviculture, 0105 earth and related environmental sciences, Risk adjusted, Expected value, 040101 forestry, Analytical expressions, Silviculture,Optimization,Thinnings,Management,Expected value,Cutting age, Global warming, Forestry, Storm, 04 agricultural and veterinary sciences, 15. Life on land, [SDE.ES]Environmental Sciences/Environmental and Society, Management, Physics - Atmospheric and Oceanic Physics, 13. Climate action, Western europe, Atmospheric and Oceanic Physics (physics.ao-ph), 0401 agriculture, forestry, and fisheries, Thinnings, [SDE.ES] Environmental Sciences/Environmental and Society, Risk assessment
Abstract: International audience; Global warming may induce in Western Europe an increase in storms. Hence the forest managers will have to take into account the risk increase. We study the impact of storm risk at the stand level. From the analytical expressions of the Faustmann criterion and the Expected Long-Run Average Yield, we deduce in presence of storm risk the influence of criteria and of discount rate in terms of optimal thinnings and cutting age. We discuss the validity of using a risk adjusted discount rate (a rate of storm risk added to the discount rate) without risk to mimic the storm risk case in terms of optimal thinnings.
Published: 2014
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24. A tree-growth model to optimize silviculture

Author: Patrice Loisel, Jean-François Dhôte, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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 Office National des Forêts (ONF)
Subjects: 0106 biological sciences, Optimization, Mathematical optimization, 010504 meteorology & atmospheric sciences, 010603 evolutionary biology, 01 natural sciences, Basal area, Economic parameters, Growth model, Control, FOS: Mathematics, Mathematics - Optimization and Control, Silviculture, 0105 earth and related environmental sciences, Mathematics, Applied Mathematics, General Engineering, General Medicine, 15. Life on land, [SDE.ES]Environmental Sciences/Environmental and Society, Computational Mathematics, Tree (data structure), Optimization and Control (math.OC), Ordinary differential equation, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], General Economics, Econometrics and Finance, Analysis
Abstract: International audience; In this paper, we present the description of a simplified model of the dynamic of a mono-specific even-aged forest. The model studied is a tree-growth model based on a system of two ordinary differential equations concerning the tree basal area and the number of trees. The analytical study of this model permits us to predict the behavior of the system solutions. We are trying to highlight the influence of economic parameters and growth parameters on the system solutions, in the framework of the optimization of silviculture.
Published: 2014
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25. Asymétrie dans des enchères à prix de retrait secret

Author: Patrice Loisel and Bernard Elyakime
Subjects: TheoryofComputation_MISCELLANEOUS, Microeconomics, Reservation price, Value (economics), Reservation, Economics, ComputingMilieux_COMPUTERSANDSOCIETY, TheoryofComputation_GENERAL, Common value auction, General Economics, Econometrics and Finance
Abstract: Asymetric auctions with secret reservation prices We examine a first-price sealed-bid auction in which the seller's reservation price is not announced in advance, and in which buyers are not symetrie. We propose a model in private value of these auctions with a secret seller's price reservation. We study this model with only two buyers : one of each type. So we can compute numerically bidders'strategies and we evaluate the expected gain for the seller in this model and in the model with a public reservation price. This last one has the higher expected gain. Another possible explanation is given to the secret reservation price in wood-auctions., Asymétrie dans des enchères à prix de retrait secret Les bois sont le plus souvent vendus en France par enchères avec prix de retrait secret. Celles-ci peuvent être raisonnablement modélisées dans le cadre de la valeur privée. Avec des acheteurs supposés symétriques, le vendeur a alors intérêt à annoncer son prix de retrait. Les acheteurs n'étant pas tous de même type, ce résultat est-il encore vrai ? Pour cela nous proposons un modèle d'enchères asymétriques à valeurs privées, sans annonce du prix de retrait du vendeur. Nous nous limitons à deux acheteurs, un de chaque type, pour déterminer l'espérance d'utilité du vendeur et la comparer à celle d'un modèle à prix de retrait public. Nous montrons que ce dernier modèle procure la plus grande espérance d'utilité au vendeur. Une hypothèse explicative du prix de retrait secret est alors proposée en conclusion., Elyakime Bernard, Loisel Patrice. Asymétrie dans des enchères à prix de retrait secret. In: Revue économique, volume 48, n°4, 1997. pp. 835-851.
Published: 1997

26. Spontaneous Emergence of a Relationship between Habitat Openness and Mean Group Size and its Possible Evolutionary Consequences in Large Herbivores

Author: Patrice Loisel, Jean-François Gerard, Unité de recherche Comportement et Ecologie de la Faune Sauvage (CEFS), Institut National de la Recherche Agronomique (INRA), and Unité de Biométrie et Intelligence Artificielle (UBIA)
Subjects: 0106 biological sciences, Statistics and Probability, Herbivore, General Immunology and Microbiology, Ecology, [SDV]Life Sciences [q-bio], Applied Mathematics, 05 social sciences, Foraging, ETHOLOGIE, General Medicine, Biology, 010603 evolutionary biology, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Intraspecific competition, Predation, Habitat, Modeling and Simulation, Openness to experience, 0501 psychology and cognitive sciences, 050102 behavioral science & comparative psychology, General Agricultural and Biological Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: Group size generally increases with habitat openness in large mammalian herbivores, be it within species or across a given taxonomic family when considering the typical habitat and herd size of each species. This correlation is often considered to be the adaptive outcome of selective pressures arising from predation and from the intraspecific competition that communal foraging may entail. However, the increase of group size with habitat openness, when it occurs within a given species, might be the simple consequence of the instability of groupings and of the increasing possibility of perceiving congeners with environment openness. This is shown in the present paper through the outcomes of a simple model for group fusion and splitting-up, which assumes that the individuals behave independently of habitat openness. Some possible evolutionary consequences of the phenomenon are discussed. The spontaneous increase of group size with environment openness might in particular have initiated the evolutionary trend to large body sizes in the herbivore species which colonized open spaces.
Published: 1995
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27. Faustmann Rotation and population dynamics in the presence of a risk of destructive events

Author: Patrice Loisel, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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), ProdInra, Migration, Analyse des Systèmes et Biométrie (ASB), Institut National de la Recherche Agronomique (INRA), and Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)
Subjects: Rotation period, 010504 meteorology & atmospheric sciences, Event (relativity), Geography, Planning and Development, Economics, Econometrics and Finance (miscellaneous), Population, Optimal cutting age, [QFIN.RM]Quantitative Finance [q-fin]/Risk Management [q-fin.RM], Rotation, 01 natural sciences, Faustmann rotation, JEL: C - Mathematical and Quantitative Methods/C.C6 - Mathematical Methods • Programming Models • Mathematical and Simulation Modeling/C.C6.C61 - Optimization Techniques • Programming Models • Dynamic Analysis, FOS: Mathematics, [QFIN.RM] Quantitative Finance [q-fin]/Risk Management [q-fin.RM], Quantitative Biology - Populations and Evolution, education, Mathematics - Optimization and Control, 0105 earth and related environmental sciences, 040101 forestry, education.field_of_study, Natural risk, Ecology, Thinning, Populations and Evolution (q-bio.PE), Forestry, JEL: D - Microeconomics/D.D8 - Information, Knowledge, and Uncertainty/D.D8.D81 - Criteria for Decision-Making under Risk and Uncertainty, 04 agricultural and veterinary sciences, 15. Life on land, Geodesy, [SDE.ES]Environmental Sciences/Environmental and Society, JEL: Q - Agricultural and Natural Resource Economics • Environmental and Ecological Economics/Q.Q2 - Renewable Resources and Conservation/Q.Q2.Q23 - Forestry, Optimization and Control (math.OC), FOS: Biological sciences, 0401 agriculture, forestry, and fisheries, Faustmann rotation,Optimal cutting age,Model,Thinning,Natural risk, [SDE.ES] Environmental Sciences/Environmental and Society, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], Geology, Model
Abstract: International audience; The impact of the presence of risk of destructive event on the silvicultural practice of a forest stand is investigated. For that, we consider a model of population dynamics. This model has allowed us to make the comparison without and with risk, and highlight the influence of the presence of risk of destructive event on optimal thinning and optimal rotation period.
Published: 2011
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28. A numerical distance based on fuzzy partitions

Author: Patrice Loisel, Serge Guillaume, Brigitte Charnomordic, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), 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 de la Recherche Agronomique (INRA), and Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
Subjects: 0209 industrial biotechnology, Fuzzy clustering, CLUSTERING, INTERPRETABLE, INTELLIGENCE ARTIFICIELLE, 02 engineering and technology, computer.software_genre, Fuzzy logic, 020901 industrial engineering & automation, Similarity (network science), 0202 electrical engineering, electronic engineering, information engineering, [INFO]Computer Science [cs], [MATH]Mathematics [math], Cluster analysis, Mathematics, business.industry, k-means clustering, Pattern recognition, GROUPAGE, K-MEANS, SIMILARITY, SIMILITUDE, 020201 artificial intelligence & image processing, Data mining, Artificial intelligence, business, computer, EXPERT KNOWLEDGE, Distance based
Abstract: This work studies a new distance function which takes into account expert knowledge by making use of fuzzy partitions. It considers the symbolic distances between concepts and is equivalent to the Euclidean distance for regular partitions made of triangular membership functions. Its behaviour is investigated in comparison with that of the Euclidean distance and its interest is shown for clustering applications.
Published: 2011
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29. Biogeography of soil microbial communities: a review and a description of the ongoing french national initiative

Author: Lionel Ranjard, Samuel Dequiedt, Claudy Jolivet, Nicolas P. A. Saby, Jean Thioulouse, Jérome Harmand, Patrice Loisel, Alain Rapaport, Saliou Fall, Pascal Simonet, Richard Joffre, Nicolas Chemidlin-Prévost Bouré, Pierre-Alain Maron, Christophe Mougel, Manuel P. Martin, Benoît Toutain, Dominique Arrouays, Philippe Lemanceau, Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), InfoSol (InfoSol), Institut National de la Recherche Agronomique (INRA), Ecologie quantitative et évolutive des communautés, Département écologie évolutive [LBBE], Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Water Resource Modeling (MERE), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de la Recherche Agronomique (INRA), Ampère (AMPERE), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Eric Lichtfouse, Marjolaine HAMELIN, Mireille NAVARRETE, Philippe Debaeke, Unité INFOSOL (ORLEANS INFOSOL), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Ampère, Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-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)-Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Unité INFOSOL ( ORLEANS INFOSOL ), Institut National de la Recherche Agronomique ( INRA ), Laboratoire de Biométrie et Biologie Evolutive ( LBBE ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique ( Inria ) -Centre National de la Recherche Scientifique ( CNRS ), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Water Resource Modeling ( MERE ), Inria Sophia Antipolis - Méditerranée ( CRISAM ), Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National de la Recherche Agronomique ( INRA ), École Centrale de Lyon ( ECL ), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Centre d’Ecologie Fonctionnelle et Evolutive ( CEFE ), and Université Paul-Valéry - Montpellier 3 ( UM3 ) -Centre international d'études supérieures en sciences agronomiques ( Montpellier SupAgro ) -École pratique des hautes études ( EPHE ) -Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut de Recherche pour le Développement ( IRD [France-Sud] ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro )
Subjects: 2. Zero hunger, 0303 health sciences, [ SDE.BE ] Environmental Sciences/Biodiversity and Ecology, [SPI.NRJ]Engineering Sciences [physics]/Electric power, microbial communities, 04 agricultural and veterinary sciences, 15. Life on land, bacterial communities, microbial ecology, diversity, Europe, 03 medical and health sciences, soil biogeography, [ SPI.NRJ ] Engineering Sciences [physics]/Electric power, 13. Climate action, soil survey, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, environment, 030304 developmental biology
Abstract: International audience; Microbial biogeography is the study of the distribution of microbial diversity on large scales of space and time. This science aims at understanding biodiversity regulation and its link with ecosystem biological functioning, goods and services such as maintenance of productivity, of soil and atmospheric quality, and of soil health. Although the initial concept dates from the early 20th century (Beijerinck (1913) De infusies en de ontdekking der backterien, in: Jaarboek van de Knoniklijke Akademie van Wetenschappen, Muller, Amsterdam), only recently have an increasing number of studies have investigated the biogeographical patterns of soil microbial diversity. A such delay is due to the constraints of the microbial models, the need to develop relevant molecular and bioinformatic tools to assess microbial diversity, and the non-availability of an adequate sampling strategy. Consequently, the conclusions from microbial ecology studies have rarely been generally applicable and even the fundamental power-laws differ because the taxa-area relationship and the influence of global and distal parameters on the spatial distribution of microbial communities have not been examined. In this article we define and discuss the scientific, technical and operational limits and outcomes resulting from soil microbial biogeography together with the technical and logistical feasibility. The main results are that microbial communities are not stochastically distributed on a wide scale and that biogeographical patterns are more influenced by local parameters such as soil type and land use than by distal ones, e. g. climate and geomorphology, contrary to plants and animals. We then present the European soil biological survey network, focusing on the French national initiative and the "ECOMIC-RMQS" project. The objective of the ECOMIC-RMQS project is to characterise the density and diversity of bacterial communities in all soils in the RMQS library in order to assess, for the first time, not only microbial biogeography across the whole of France but also the impact of land use on soil biodiversity (Reseau de Mesures de la Qualite des Sols = French Soil Quality Monitoring Network, 2200 soils covering all the French territory with a systematic grid of sampling). The scientific, technical and logistical outputs are examined with a view to the future prospects needed to develop this scientific domain and its applications in sustainable land use.
Published: 2011
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30. Biogeography of soil microbial communities: a review and a description of the ongoing french national initiative

Author: Dominique Arrouays, Manuel Martin, Lionel Ranjard, Jérôme Harmand, Richard Joffre, Philippe Lemanceau, Nicolas Chemidlin-Prevost Boure, Claudy Jolivet, Saliou Fall, Nicolas Saby, Benoit Toutain, Pascal Simonet, Christophe Mougel, Pierre-Alain Maron, Alain Rapaport, Jean Thioulouse, Samuel Dequiedt, Patrice Loisel, Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), GenoSol (plateforme de l'université de Bourgogne), Agroécologie [Dijon], Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ) -AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Unité INFOSOL ( ORLEANS INFOSOL ), Institut National de la Recherche Agronomique ( INRA ), Laboratoire de Biométrie et Biologie Evolutive ( LBBE ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique ( Inria ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Water Resource Modeling ( MERE ), Inria Sophia Antipolis - Méditerranée ( CRISAM ), Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National de la Recherche Agronomique ( INRA ), Ampère, Département Bioingénierie ( BioIng ), Ampère, École Centrale de Lyon ( ECL ), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Institut National des Sciences Appliquées de Lyon ( INSA Lyon ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ) -École Centrale de Lyon ( ECL ), Université de Lyon-Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Centre d’Ecologie Fonctionnelle et Evolutive ( CEFE ), Université Paul-Valéry - Montpellier 3 ( UM3 ) -Centre international d'études supérieures en sciences agronomiques ( Montpellier SupAgro ) -École pratique des hautes études ( EPHE ) -Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Université de Montpellier ( UM ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut de Recherche pour le Développement ( IRD [France-Sud] ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), FLAveur, VIsion et Comportement du consommateur (FLAVIC), Etablissement National d'Enseignement Supérieur Agronomique de Dijon (ENESAD)-Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), InfoSol (InfoSol), Institut National de la Recherche Agronomique (INRA), Ecologie quantitative et évolutive des communautés, Département écologie évolutive [LBBE], Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), 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 de la Recherche Agronomique (INRA), Water Resource Modeling (MERE), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de la Recherche Agronomique (INRA), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Ampère, Département Bioingénierie (BioIng), Ampère (AMPERE), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-École Centrale de Lyon (ECL), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-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 de Recherche pour le Développement (IRD [France-Sud]), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement-Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Unité INFOSOL (ORLEANS INFOSOL), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-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)-Université Paul-Valéry - Montpellier 3 (UM3), Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Environmental Engineering, sol, Soil biodiversity, Biodiversity, microbial communities, Biology, microbial ecology, diversity, [ SDV.EE ] Life Sciences [q-bio]/Ecology, environment, Soil survey, 03 medical and health sciences, Pedology, [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences, 030304 developmental biology, diversité, 2. Zero hunger, Soil health, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, 0303 health sciences, écologie microbienne, Land use, 030306 microbiology, business.industry, Ecology, Environmental resource management, 15. Life on land, Soil type, bacterial communities, Soil quality, SOIL BIOGEOGRAPHY, MICROBIAL COMMUNITIES, SOIL SURVEY, MICROBIAL ECOLOGY, DIVERSITY, Agricultural sciences, Europe, soil biogeography, 13. Climate action, soil survey, business, Agronomy and Crop Science, environment, Sciences agricoles
Abstract: International audience; Microbial biogeography is the study of the distribution of microbial diversity on large scales of space and time. This science aims at understanding biodiversity regulation and its link with ecosystem biological functioning, goods and services such as maintenance of productivity, of soil and atmospheric quality, and of soil health. Although the initial concept dates from the early 20th century (Beijerinck (1913) De infusies en de ontdekking der backterien, in: Jaarboek van de Knoniklijke Akademie van Wetenschappen, Muller, Amsterdam), only recently have an increasing number of studies have investigated the biogeographical patterns of soil microbial diversity. A such delay is due to the constraints of the microbial models, the need to develop relevant molecular and bioinformatic tools to assess microbial diversity, and the non-availability of an adequate sampling strategy. Consequently, the conclusions from microbial ecology studies have rarely been generally applicable and even the fundamental power-laws differ because the taxa-area relationship and the influence of global and distal parameters on the spatial distribution of microbial communities have not been examined. In this article we define and discuss the scientific, technical and operational limits and outcomes resulting from soil microbial biogeography together with the technical and logistical feasibility. The main results are that microbial communities are not stochastically distributed on a wide scale and that biogeographical patterns are more influenced by local parameters such as soil type and land use than by distal ones, e.g. climate and geomorphology, contrary to plants and animals. We then present the European soil biological survey network, focusing on the French national initiative and the "ECOMIC-RMQS" project. The objective of the ECOMIC-RMQS project is to characterise the density and diversity of bacterial communities in all soils in the RMQS library in order to assess, for the first time, not only microbial biogeography across the whole of France but also the impact of land use on soil biodiversity (Réseau de Mesures de la Qualité des Sols = French Soil Quality Monitoring Network, 2200 soils covering all the French territory with a systematic grid of sampling). The scientific, technical and logistical outputs are examined with a view to the future prospects needed to develop this scientific domain and its applications in sustainable land use.
Published: 2010
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31. Distribution et déterminisme de la diversité des communautés de champignons telluriques à l'échelle de trois régions françaises

Author: Nicolas Chemidlin Prévost-Bouré, Dequiedt, Samuel S., Rémy Doyen, Lelievre, Mélanie M., Claudy Jolivet, Manuel Martin, Nicolas Saby, Benoit Toutain, Dominique Arrouays, Jerome Harmand, Patrice Loisel, Jean Thioulouse, Pierre-Alain Maron, Lemanceau, Philippe P., Lionel Ranjard, Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Unité de service Infosol ( INFOSOL ), Institut National de la Recherche Agronomique ( INRA ), Infosol, Unité INFOSOL ( ORLEANS INFOSOL ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Ecosystem Management, Armidale, University of New England ( UNE ), ProdInra, Archive Ouverte, Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), InfoSol (InfoSol), Institut National de la Recherche Agronomique (INRA), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut National de la Recherche Agronomique (INRA)-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), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Association Francophone d'Ecologie Microbienne (AFEM). FRA., Unité INFOSOL, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), and Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro )
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, stomatognathic diseases, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, régions françaises, communauté de champignon tellurique régions françaises, [ INFO.INFO-OH ] Computer Science [cs]/Other [cs.OH], [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences, communauté de champignon tellurique
Abstract: aeres : C-ACTN; National audience; no abstract
Published: 2009

32. Patterns biogéographiques de la diversité bactérienne des sols à l'échelle du territoire national

Author: Dequiedt, Samuel S., Lelievre, Mélanie M., Claudy Jolivet, Martin, Manuel M., Saby, Nicolas N., Toutain, Benoit B., Arrouays, Dominique D., Nicolas Chemidlin Prévost-Bouré, Harmand, Jerome J., Patrice Loisel, Jean Thioulouse Thioulouse, Pierre-Alain Maron, Lemanceau, Philippe P., Lionel Ranjard, Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Unité de service Infosol ( INFOSOL ), Institut National de la Recherche Agronomique ( INRA ), Infosol, Unité INFOSOL ( ORLEANS INFOSOL ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Ecosystem Management, Armidale, University of New England ( UNE ), Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), InfoSol (InfoSol), Institut National de la Recherche Agronomique (INRA), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut National de la Recherche Agronomique (INRA)-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), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), SDAR Occitanie Montpellier (SDAR), Labo/service de l'auteur, Ville service., Unité INFOSOL, Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), ProdInra, Archive Ouverte, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), and SDAR Occitanie Montpellier ( SDAR )
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, PEDOLOGIE, [ INFO.INFO-OH ] Computer Science [cs]/Other [cs.OH], [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences, ComputingMilieux_MISCELLANEOUS
Abstract: aeres : C-COM; National audience; no abstract
Published: 2009

33. Vigilance and its complex synchrony in the red-necked pademelon, Thylogale thetis

Author: Peter J. Jarman, Patrice Loisel, Olivier Pays, Anne W. Goldizen, Anne-Laure Dubot, Paysages et Biodiversité, Université d'Angers (UA), School of Integrative Biology, University of Queesland, University of Queensland [Brisbane], Analyse des Systèmes et Biométrie (ASB), Institut National de la Recherche Agronomique (INRA), Ecosystem Management, Armidale, University of New England (UNE), School of Integrative Biology, Brisbane, and School of Integrative Biology, University of Queensland
Subjects: 0106 biological sciences, RED-NECKED PADEMELON SURVIVAL ESTIMATION ANIMAL BEHAVIOR PREDATOR CONTROL ANTIPREDATOR BEHAVIOR INDEPENDENT SCANNING NEIGHBOR EFFECT SYNCHRONIZATION OF VIGILANCE VIGILANCE ECOLOGIE COEXISTENCE DES ESPECES, biology, Neighbor effect, Ecology, Pademelon, 05 social sciences, Foraging, [INFO.INFO-OH]Computer Science [cs]/Other [cs.OH], Red necked, 15. Life on land, biology.organism_classification, 010603 evolutionary biology, 01 natural sciences, Predation, Vigilance (behavioural ecology), 0501 psychology and cognitive sciences, Animal Science and Zoology, 050102 behavioral science & comparative psychology, Natural enemies, Thylogale thetis, Ecology, Evolution, Behavior and Systematics
Abstract: Several adaptive functions, including gaining information from other group members and detecting predators, are generally ascribed to vigilance in groups of animals subject to predation. Most studies of the effects of neighbors on vigilance have focused on individual vigilance. We investigated the effects of neighbors on vigilance in wild red-necked pademelons Thylogale thetis foraging at night in nonpersistent aggregations in a clearing in rain forest. Neither the total number of pademelons in the clearing nor the numbers at various distances around focal individuals affected the individual vigilance of focal animals. However, focal animals' individual vigilance did change with the distance to their nearest neighbor and also with distance to cover. Pairs of individuals closer than 10 m apart tended to synchronize their bouts of individual vigilance and foraging. The degree of synchrony within pairs increased with both distance to cover and the total number of pademelons foraging in the area and decreased with increasing distance to the pair's nearest neighbor but did not vary with the distance separating the members of the pair. Thus, despite their individual vigilance being unaffected by the number of other pademelons in the feeding aggregation, pademelons were nonetheless sensitive to the presence of conspecifics and adjusted their behavior in relation to their separation from neighbors. Thus, some vigilance benefits may be obtained from the presence of conspecifics even in species that aggregate only temporarily on food patches without forming more permanent social groups. Copyright 2009, Oxford University Press.
Published: 2009
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34. How to model marine reserves?

Author: Pierre Cartigny, Patrice Loisel, Analyse des Systèmes et Biométrie (ASB), Institut National de la Recherche Agronomique (INRA), Groupement de Recherche en Économie Quantitative d'Aix-Marseille (GREQAM), École Centrale de Marseille (ECM)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École des hautes études en sciences sociales (EHESS), Ecosystem Management, Armidale, University of New England (UNE), École des hautes études en sciences sociales (EHESS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Rapaport, Alain, 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 de la Recherche Agronomique (INRA), and ProdInra, Migration
Subjects: [INFO.INFO-OH]Computer Science [cs]/Other [cs.OH], CALCULUS OF VARIATION, Safeguarding, 01 natural sciences, DYNAMICAL SYSTEM, HALIEUTICS RESOURCES DYNAMICAL SYSTEM CALCULUS OF VARIATION INFINITE HORIZON MARINE RESERVE BIOECONOMIC MODEL ECOLOGIE VARIATION DE CALCUL HORIZON INFINIE BIODIVERSITE MARINE, [STAT.AP] Statistics [stat]/Applications [stat.AP], BIOECONOMIC MODEL, 0502 economics and business, MARINE RESERVE, FOS: Mathematics, Economics, 14. Life underwater, 0101 mathematics, Mathematics - Optimization and Control, HALIEUTICS RESOURCES, [STAT.AP]Statistics [stat]/Applications [stat.AP], BIODIVERSITE MARINE, Applied Mathematics, 05 social sciences, Marine reserve, Principal (computer security), General Engineering, General Medicine, Bioeconomics, Optimal management, [INFO.INFO-OH] Computer Science [cs]/Other [cs.OH], 010101 applied mathematics, INFINITE HORIZON, Computational Mathematics, HORIZON INFINIE, Work (electrical), Optimization and Control (math.OC), 13. Climate action, VARIATION DE CALCUL, Infinite horizon, 050202 agricultural economics & policy, [MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC], General Economics, Econometrics and Finance, Mathematical economics, Analysis, ECOLOGIE
Abstract: aeres : C-COM; International audience; The safeguarding of resources is one of the principal subjects of halieutics studies. Among the solutions proposed to avert the disappearance of species, the setting in place of preservation (no take) reserves is often mentioned. Most work on this subject, theoretical as well as applied, was undertaken in recent years. In this paper, we seek to compare two different models presented in existing literature by highlighting their underlying assumptions. Both models were derived from what is often referred to as the "model of Schaefer-Clark" (reference to the work of the last author on Mathematical Bioeconomics: Clark [C.W. Clark, Mathematical Bioecomics: The Optimal Management of Renewable Resources, 2nd ed., John Wiley and Sons, New-York, 1990]). We show that various variations of this model lead to properties that can be very different.
Published: 2009
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35. Microbial-biogeography of France by the use of molecular tools applied to the French soil quality monitoring network (RMQS)

Author: Lionel Ranjard, Dequiedt, Samuel S., Lelievre, Mélanie M., Claudy Jolivet, Saby, Nicolas N., Martin, Manuel M., Jean Thioulouse Thioulouse, Harmand, Jerome J., Patrice Loisel, Arrouays, Dominique D., Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Unité INFOSOL, Institut National de la Recherche Agronomique (INRA), SDAR Occitanie Montpellier (SDAR), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Institut National de la Recherche Agronomique ( INRA ), SDAR Occitanie Montpellier ( SDAR ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), InfoSol (InfoSol), 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 Labo/service de l'auteur, Ville service, Pays service.
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, rmqs, sol, microorganisme, biologie du sol, PEDOLOGIE, adn, réseau de mesures, europe, france, [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences, analyse de sol, qualité du sol
Abstract: absent
Published: 2008

36. Prédiction du comportement des solutions d’un modèle de type Fagacée

Author: Patrice Loisel, Pierre Cartigny, Jean-François Dhôte, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Groupement de Recherche en Économie Quantitative d'Aix-Marseille (GREQAM), École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École des hautes études en sciences sociales (EHESS), Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, 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 de la Recherche Agronomique (INRA), École Centrale de Marseille (ECM)-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), AgroParisTech-Institut National de la Recherche Agronomique (INRA), ProdInra, Archive Ouverte, École des hautes études en sciences sociales (EHESS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), and Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)
Subjects: [SDV] Life Sciences [q-bio], HETRE, [SDV]Life Sciences [q-bio], FAGACEA, CHENE
Abstract: absent
Published: 2008

37. Modeling the Time Dependence of Nitrogen Uptake in Young Trees

Author: Patrice Loisel, D. Wallach, R. Habib, Bruno Goffinet, Unité de Biométrie et Intelligence Artificielle (UBIA), Institut National de la Recherche Agronomique (INRA), and Unité d'écophysiologie et horticulture
Subjects: 0106 biological sciences, Polynomial, Mean squared error, [SDV]Life Sciences [q-bio], chemistry.chemical_element, 04 agricultural and veterinary sciences, Function (mathematics), 01 natural sciences, Nitrogen, Efficiency factor, Prunus, Agronomy, chemistry, PECHER, Botany, Statistics, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Tree (set theory), Agronomy and Crop Science, ComputingMilieux_MISCELLANEOUS, Fruit tree, 010606 plant biology & botany, Mathematics
Abstract: In order to develop improved fertilization strategies for fruit trees, it is necessary to have a quantitative understanding of the dynamics of N uptake. This study was conducted to select a mathematical model for describing N uptake in young peach trees (Prunus persica (L.) Batsch). In 1985 young peach trees were grown outdoors in Avignon, France, in sand-filled containers from late February to late September. At each of nine dates total tree N was measured by destructive sampling of three trees. The differences in total N between dates are related to N uptake. The models considered all take the form of a Michaelis-Menten equation, with maximum uptake expressed as the product of total root weight and uptake efficiency. The models differ in that they express the efficiency factor as different order polynomial functions of time. The criterion used for selecting a best model was related to the squared error of prediction integrated over time. The value of the criterion was estimated for each model, and it was found that the model that expressed efficiency as a third-order polynomial function of time had the smallest value of the criterion, and was therefore the model of choice. According to this model, N uptake efficiency increased from near zero in mid-April to a maximum of 3.1 pg N/g root/d in late May, and then decreased again to near zero in late September.
Published: 1990
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38. Le projet ECOMIC-RMQS ou comment faire de la microbiogéographie à l'échelle de la France

Author: Dequiedt, Samuel S., Lelievre, Mélanie M., Claudy Jolivet, Manuel Martin, Nicolas Saby, Dominique Arrouays, Jerome Harmand, Patrice Loisel, Jean Thioulouse, Lemanceau, Philippe P., Lionel Ranjard, Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Unité INFOSOL, Institut National de la Recherche Agronomique (INRA), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), SDAR Occitanie Montpellier (SDAR), InfoSol (InfoSol), Institut National de la Recherche Agronomique (INRA)-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), Labo/service de l'auteur, Ville service, Pays service., ProdInra, Archive Ouverte, Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Institut National de la Recherche Agronomique ( INRA ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), and SDAR Occitanie Montpellier ( SDAR )
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, PEDOLOGIE, ecomic-rmqs, [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences
Abstract: absent
Published: 2007

39. Probability distribution of haplotype frequencies under the two-locus Wright-Fisher model by diffusion approximation

Author: Patrice Loisel, Simon Boitard, Unité de Biométrie et Intelligence Artificielle (UBIA), Institut National de la Recherche Agronomique (INRA), Analyse des Systèmes et Biométrie (ASB), and ProdInra, Migration
Subjects: WRIGHT–FISHER MODEL, [SDV]Life Sciences [q-bio], Monte Carlo method, Population, Linkage Disequilibrium, Gene Frequency, POPULATION GENETICS, Statistics, Quantitative Biology::Populations and Evolution, Statistical physics, education, Ecology, Evolution, Behavior and Systematics, METHODE DES DIFFERENCES FINIES, Mathematics, KOLMOGOROV FORWARD EQUATION, FREQUENCE, [SDV.EE]Life Sciences [q-bio]/Ecology, environment, education.field_of_study, Models, Genetic, FINITE DIFFERENCE SCHEME, HAPLOTYPE FREQUENCY, Numerical analysis, Finite difference, Heavy traffic approximation, Quantitative Biology::Genomics, Markov Chains, METHODE MONTE CARLO, DIFFUSION PROCESSES, [SDV] Life Sciences [q-bio], WRIGHT-FISHER MODELE, Genetics, Population, Diffusion process, Haplotypes, Kolmogorov equations, Probability distribution, GENETIQUE DES POPULATIONS, Monte Carlo Method, WRIGHT-FISHER MODEL
Abstract: The probability distribution of haplotype frequencies in a population, and the way it is influenced by genetical forces such as recombination, selection, random drift … is a question of fundamental interest in population genetics. For large populations, the distribution of haplotype frequencies for two linked loci under the classical Wright–Fisher model is almost impossible to compute because of numerical reasons. However the Wright–Fisher process can in such cases be approximated by a diffusion process and the transition density can then be deduced from the Kolmogorov equations. As no exact solution has been found for these equations, we developed a numerical method based on finite differences to solve them. It applies to transient states and models including selection or mutations. We show by several tests that this method is accurate for computing the conditional joint density of haplotype frequencies given that no haplotype has been lost. We also prove that it is far less time consuming than other methods such as Monte Carlo simulations.
Published: 2007
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40. Prey synchronize their vigilant behaviour with other group members

Author: Maud Petit, Olivier Pays, Jean-François Gerard, Pierre-Cyril Renaud, Peter Jarman, Patrice Loisel, Université d'Angers (UA), Programme ECOFAC / PDZCV, Partenaires INRAE, Analyse des Systèmes et Biométrie (ASB), Institut National de la Recherche Agronomique (INRA), Unité de recherche Comportement et Ecologie de la Faune Sauvage (CEFS), and University of New England (UNE)
Subjects: 0106 biological sciences, [SDV]Life Sciences [q-bio], Population, GROUP SIZE, ETHOLOGIE, 010603 evolutionary biology, 01 natural sciences, Statistics, Nonparametric, General Biochemistry, Genetics and Molecular Biology, Synchronization, Predation, SYNCHRONISATION, Predatory behavior, DEFASSA WATERBUCK, Group (periodic table), Animals, 0501 psychology and cognitive sciences, [INFO]Computer Science [cs], 050102 behavioral science & comparative psychology, [MATH]Mathematics [math], education, VIGILANCE, General Environmental Science, education.field_of_study, Behavior, Animal, General Immunology and Microbiology, 05 social sciences, Videotape Recording, Ruminants, General Medicine, KOBUS ELLIPSIPRYMNUS DEFASSA, ANTI PREDATOR BEHAVIOUR, Central African Republic, Vigilance (behavioural ecology), ALLELOMIMESIS, Predatory Behavior, Linear Models, Allelomimetic behavior, AFRICAN ANTILOPE, General Agricultural and Biological Sciences, Psychology, Social psychology, Research Article
Abstract: It is generally assumed that an individual of a prey species can benefit from an increase in the number of its group's members by reducing its own investment in vigilance. But what behaviour should group members adopt in relation to both the risk of being preyed upon and the individual investment in vigilance? Most models assume that individuals scan independently of one another. It is generally argued that it is more profitable for each group member owing to the cost that coordination of individual scans in non-overlapping bouts of vigilance would require. We studied the relationships between both individual and collective vigilance and group size in Defassa waterbuck, Kobus ellipsiprymnus defassa , in a population living under a predation risk. Our results confirmed that the proportion of time an individual spent in vigilance decreased with group size. However, the time during which at least one individual in the group scanned the environment (collective vigilance) increased. Analyses showed that individuals neither coordinated their scanning in an asynchronous way nor scanned independently of one another. On the contrary, scanning and non-scanning bouts were synchronized between group members, producing waves of collective vigilance. We claim that these waves are triggered by allelomimetic effects i.e. they are a phenomenon produced by an individual copying its neighbour's behaviour.
Published: 2007
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41. Denaturing gradient electrophoresis (DGE) and single-strand conformation polymorphism (SSCP) molecular fingerprintings revisited by simulation and used as a tool to measure microbial diversity

Author: Claude Lobry, Patrice Loisel, Eric Latrille, Jérôme Harmand, Olivier Zemb, Jean Philippe Delgenes, Jean-Jacques Godon, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Water Resource Modeling (MERE), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de la Recherche Agronomique (INRA), 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 Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)
Subjects: DNA, Bacterial, Swine, Microbial diversity, In silico, Biology, Microbiology, Feces, 03 medical and health sciences, Microbial ecosystem, DENATURING GRADIENT ELECTROPHORESIS, Animals, Polymorphism, Single-Stranded Conformational, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, 0303 health sciences, SINGLE STRAND CONFORMATION POLYMORPHISM, Bacteria, 030306 microbiology, Single-strand conformation polymorphism, respiratory system, DNA Fingerprinting, Molecular biology, Electrophoresis, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Evolutionary biology, Data Interpretation, Statistical, Log-normal distribution, Electrophoresis, Polyacrylamide Gel, human activities
Abstract: Summary The exact extent of microbial diversity remains unknowable. Nevertheless, fingerprinting patterns (denaturing gradient electrophoresis (DGE), single- strand conformation polymorphism (SSCP)) provide an image of a microbial ecosystem and contain diversity data. We generated numerical simulation fingerprinting patterns based on three types of distribution (uniform, geometric and lognormal) with a range of units from 10 to 500 000. First, simulated patterns containing a diversity of around 1000 units or more gave patterns similar to those obtained in experiments. Second, the number of bands or peaks saturated quickly to about 35 and were unrelated to the degree of diversity. Finally, assuming lognormal distribution, we used an estimator of diversity on in silico and experimental fingerprinting patterns. Results on in silico patterns corresponded to the sim- ulation inputs. Diversity results in experimental pat- terns were in the same range as those obtained from the same DNA sample in molecular inventories. Thus, fingerprinting patterns contain extractable data about diversity although not on the basis of a number of bands or peaks, as is generally assumed to be the case.
Published: 2006
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42. Incentive contract and weather risk

Author: Patrice Loisel, Bernard Elyakime, Analyse des Systèmes et Biométrie (ASB), Institut National de la Recherche Agronomique (INRA), and Station d'économie et sociologie rurales
Subjects: Economics and Econometrics, Moral hazard, media_common.quotation_subject, Weather risk, Contract management, Social Welfare, Management, Monitoring, Policy and Law, Environmental economics, Payment, [SHS.ECO]Humanities and Social Sciences/Economics and Finance, Ecosystem services, Microeconomics, Incentive, Economics, Production (economics), media_common
Abstract: We study contracts designed to remunerate a farmer for the production of an ecosystem service with the payment dependent on the results of the farmer’s actions and on weather conditions. Two contracts are proposed: the first takes into account both the results of the farmer’s actions and a weather variable that reflects the actual atmospheric conditions during the life of the contract; the second bases the payment on the results alone incorporating only the average effect of weather. Social welfare is optimal when both the results and the specific atmospheric conditions are taken into account; however, this type of contract may be less acceptable to the farmer due to his perception of the level of risk involved.; Les auteurs centrent leur démarche sur un contrat incitatif. Ce contrat permet de rémunérer un agriculteur afin qu'il produise une externalité positive désirée et rémunérée par la société. Le principal dispose, en plus de la loi de densité de probabilité sur la production (indicée par les actions), d'un signal climatique qui influence la production. Les auteurs mettent en évidence un premier contrat avec paiement selon le niveau de production de l'externalité et selon la valeur d'une variable climatique puis un autre contrat dans lequel l'effet climatique est pris en moyenne. L'utilité sociale est optimale dans le premier contrat mais ce type de contrat peut être peu acceptable pour le contractant au terme de prise de risque.
Published: 2006
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43. Herd size in large herbivores: encoded in the individual or emergent?

Author: Carole Marchal, Eric Bideau, Jean-François Gerard, Patrice Loisel, Marie-Line Maublanc, Unité de recherche Comportement et Ecologie de la Faune Sauvage (CEFS), Institut National de la Recherche Agronomique (INRA), Analyse des Systèmes et Biométrie (ASB), and ProdInra, Migration
Subjects: 0106 biological sciences, Empirical data, Property (philosophy), [SDV]Life Sciences [q-bio], Biology, 010603 evolutionary biology, 01 natural sciences, Models, Biological, Animals, 0501 psychology and cognitive sciences, Ecosystem, 050102 behavioral science & comparative psychology, ComputingMilieux_MISCELLANEOUS, Population Density, Herbivore, Behavior, Animal, Ecology, Deer, 05 social sciences, Adaptive response, Biological evolution, Biological Evolution, [SDV] Life Sciences [q-bio], Habitat, Evolutionary biology, Herd, General Agricultural and Biological Sciences
Abstract: In large mammalian herbivores, the increase of group size with habitat openness was first assumed to be an adaptive response, encoded in the individual. However, it could, alternatively, be an emergent property: if groups were nonpermanent units, often fusing and splitting up, then any increase of the distance at which animals perceive one another could increase the rate of group fusion and thus mean group size. Dynamical models and empirical data support this second hypothesis. This is not to say that adaptive modifications of mean herd size cannot occur. However, this changes the way in which we can envisage the history of gregariousness in large herbivores during the Tertiary.
Published: 2002

44. Detecting a major gene in an F2 population

Author: G. Montes De Oca, Patrice Loisel, Bruno Goffinet, Hervé Monod, Unité de Biométrie et Intelligence Artificielle (UBIA), Institut National de la Recherche Agronomique (INRA), and Unité de recherche Biométrie (UB)
Subjects: 0106 biological sciences, Statistics and Probability, Biometry, [SDV]Life Sciences [q-bio], Positive-definite matrix, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Normal distribution, 010104 statistics & probability, symbols.namesake, Statistics, Animals, 0101 mathematics, Fisher information, Crosses, Genetic, Mathematics, Models, Statistical, General Immunology and Microbiology, Models, Genetic, Applied Mathematics, General Medicine, Plants, Major gene, Likelihood-ratio test, F2 population, symbols, General Agricultural and Biological Sciences, 010606 plant biology & botany
Abstract: The aim of this paper is to study the behavior of the likelihood ratio test for the detection of a major gene in an F2 population. The model is a mixture of three normal distributions where the proportions are known. The information matrix is not positive definite, and therefore classical results cannot be used. An example concerning beans is given.
Published: 1994

45. Effect of parameter estimation on fertilizer optimization

Author: D. Wallach, Patrice Loisel, Unité de Biométrie et Intelligence Artificielle (UBIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: Statistics and Probability, education.field_of_study, Estimation theory, [SDV]Life Sciences [q-bio], Population, Estimator, Value (computer science), engineering.material, Confidence interval, Statistics, engineering, Production (economics), Profitability index, Fertilizer, Statistics, Probability and Uncertainty, education, Mathematics
Abstract: It is important to optimize the amount of fertilizer applied to a crop, both to improve profitability and to reduce environmental damage. Previous work has concentrated mainly on modelling the response of production to fertilizer. Here we complement this work by concentrating on the effect of parameter estimation on the value of the objective function. A simple expression for confidence intervals for the value of the true optimal strategy is obtained. Also, a risk function for the effect of using an estimated optimal strategy is proposed, and a simple estimator derived. The results are applied first to fertilizer optimization for a single field, and then for a population of fields.
Published: 1994

46. Testing in normal mixture models when the proportions are known

Author: Bruno Goffinet, Patrice Loisel, Béatrice Laurent, Unité de Biométrie et Intelligence Artificielle (UBIA), and Institut National de la Recherche Agronomique (INRA)
Subjects: Statistics and Probability, Applied Mathematics, General Mathematics, [SDV]Life Sciences [q-bio], Variance (accounting), GENETIQUE, Mixture model, Agricultural and Biological Sciences (miscellaneous), Likelihood-ratio test, Statistics, A priori and a posteriori, Statistics, Probability and Uncertainty, General Agricultural and Biological Sciences, Statistic, Mathematics, Curse of dimensionality
Abstract: SUMMARY The aim of this paper is to study the behaviour of the likelihood ratio test statistic in mixture models when the proportions of the distributions are known a priori. The results depend on the value of the proportion, the dimensionality of the problem and whether or not the variance of the distributions is known.
Published: 1992

47. Auctioning and Bargaining: An Econometric Study of Timber Auctions with Secret Reservation Prices

Author: Quang Vuong, Jean-Jacques Laffont, Bernard Elyakime, and Patrice Loisel
Subjects: TheoryofComputation_MISCELLANEOUS, Statistics and Probability, Bargaining problem, Economics and Econometrics, Reservation, TheoryofComputation_GENERAL, Outcome (game theory), Microeconomics, Reservation price, Bayesian game, Economics, ComputingMilieux_COMPUTERSANDSOCIETY, Common value auction, Statistics, Probability and Uncertainty, Mathematical economics, Social Sciences (miscellaneous)
Abstract: This article considers a first-price sealed-bid auction at which the seller's reservation price is not announced in advance. We allow for a second round of bargaining and consider the Nash bargaining outcome when the object is unsold after the auctioning round. We characterize the bidders' and seller's Bayesian Nash equilibrium strategies. The distributions of the buyers' and seller's private values are estimated by nonlinear least squares from auction data on standing timber, while solving numerically the differential equations characterizing the seller's and buyers' equilibrium strategies. The performance of the estimated model is then compared to a model in which the players behave myopically.
Published: 1997
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48. Prey synchronize their vigilant behaviour with other group members.

Author: Olivier Pays, Pierre-Cyril Renaud, Patrice Loisel, Maud Petit, Jean-FranÃ§ois Gerard, and Peter J. Jarman
Subjects: PREDATION, WATERBUCK, SPECIES diversity, DEATH (Biology)
Abstract: It is generally assumed that an individual of a prey species can benefit from an increase in the number of its group's members by reducing its own investment in vigilance. But what behaviour should group members adopt in relation to both the risk of being preyed upon and the individual investment in vigilance? Most models assume that individuals scan independently of one another. It is generally argued that it is more profitable for each group member owing to the cost that coordination of individual scans in non-overlapping bouts of vigilance would require. We studied the relationships between both individual and collective vigilance and group size in Defassa waterbuck, Kobus ellipsiprymnus defassa, in a population living under a predation risk. Our results confirmed that the proportion of time an individual spent in vigilance decreased with group size. However, the time during which at least one individual in the group scanned the environment (collective vigilance) increased. Analyses showed that individuals neither coordinated their scanning in an asynchronous way nor scanned independently of one another. On the contrary, scanning and non-scanning bouts were synchronized between group members, producing waves of collective vigilance. We claim that these waves are triggered by allelomimetic effects i.e. they are a phenomenon produced by an individual copying its neighbour's behaviour. [ABSTRACT FROM AUTHOR]
Published: 2007
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49. Microbiogéographie à l'échelle du territoire national

Author: Dequiedt, Samuel S., Lelievre, Mélanie M., Claudy Jolivet, Martin, Manuel M., Saby, Nicolas N., Arrouays, Dominique D., Harmand, Jerome J., Patrice Loisel, Jean Thioulouse Thioulouse, Lemanceau, Philippe P., Lionel Ranjard, Microbiologie du Sol et de l'Environnement (MSE), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Unité INFOSOL, Institut National de la Recherche Agronomique (INRA), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), SDAR Occitanie Montpellier (SDAR), InfoSol (InfoSol), 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), Labo/service de l'auteur, Ville service, Pays service., ProdInra, Archive Ouverte, Microbiologie du Sol et de l'Environnement ( MSE ), Institut National de la Recherche Agronomique ( INRA ) -Université de Bourgogne ( UB ), Institut National de la Recherche Agronomique ( INRA ), Laboratoire de Biotechnologie de l'Environnement [Narbonne] ( LBE ), Institut national de la recherche agronomique [Montpellier] ( INRA Montpellier ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie ( MISTEA ), Institut National de la Recherche Agronomique ( INRA ) -Institut national d’études supérieures agronomiques de Montpellier ( Montpellier SupAgro ), and SDAR Occitanie Montpellier ( SDAR )
Subjects: [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, [SDV.SA] Life Sciences [q-bio]/Agricultural sciences, PEDOLOGIE, [ SDV.SA ] Life Sciences [q-bio]/Agricultural sciences
Abstract: absent

50. Modelling the population dynamics of a native plant: application to sustainable management of the babassu palm tree in Brazil

Author: Nikolay Sirakov, Patrice Loisel, Danielle Mitja, Thérèse Libourel Rouge, Santos, A. M. D., Souza Miranda, I., ProdInra, Migration, Mathématiques, Informatique et STatistique pour l'Environnement et l'Agronomie (MISTEA), Institut National de la Recherche Agronomique (INRA)-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 de Recherche pour le Développement (IRD), UMR 228 Espace-Dev, Espace pour le développement, Université de Guyane (UG)-Université des Antilles (UA)-Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM), Université Montpellier 2 - Sciences et Techniques (UM2), Universidade Federal Rural da Amazônia (UFRA), 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)-Institut National de la Recherche Agronomique (INRA)
Subjects: [STAT.AP]Statistics [stat]/Applications [stat.AP], [STAT.AP] Statistics [stat]/Applications [stat.AP]
Abstract: National audience; Largely represented in Brazil, the babassu palm (Attalea speciosa Mart. ex Spreng.) is an endemic species of the primary forests in South America. In these forests the progress of the pioneer front has highlighted the babassu in the henceforth man-made open areas: pastures and cultivated fields. Babassu is a part of the "extractive" resources: gathering activity followed by marketing of non-timber products. According to estimates, this activity involves two million people among the most disadvantaged in the country. Despite this fact, the knowledge of sustainable functioning of this species among these anthropic environments are sorely lacking. Our work serves to clarify this functioning and to provide support of local populations to guide them towards a sustainable management of the babassu. This work is organized around the selection and the implementation of a mathematical model of population dynamics. The matrix transition models (integrating only stages) are the most commonly used. However, we have selected a model from those used for modelling Arecaceae which is based on the cohorts (integrates stage and age). We finally confronted these two models. The results obtained in this study have shown that the model we have proposed is more suitable than the currently used matrix transition models. This substitution model can better integrate the concept of annual variability in population caused by both the external and internal factors. We have proved that the concept of age of the individual is essential and inseparable from that of stage. The results obtained from simulations based on our model indicate that the unstationarity and stochasticity can be introduced for both parameters. Currently our team conducts a three years field study in Brazil. The results will allow us to have a clearer outline of the structure of our model. Moreover, these data will serve to feed and calibrate the model.

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