• Energy Research
• 15. Life on land close
• 12. Responsible consumption close
• FR close
• ES close
• French close

[Paper in French] The European public policy in favor of the biodiesel consumption is highly debated. Available estimates of the induced land use changes conclude that this policy is inefficient to reduce emissions of GreenHouse Gas. We show that the crop yield evolutions in these estimates are significantly lower than the observed and expected evolutions. This difference is directly related to biased calibration choice of behavioral parameters. We show using the GTAP-BIO framework that a consistent calibration of these parameters leads to a strong reduction (by around 80% in the long run) of the land use changes and induced emissions.

Income source and accompaniment needs of family farms in the cotton growing area of West Burkina Faso Description of the subject. In the western cotton growing area of Burkina Faso, the variability and the diversity of the income levels of family farms (EAFs) mean that these farms require suitable agronomic accompaniment. Objectives. This article gives an account of this diversity and the need for accompaniment according to the type of identified EAF.Method. The data were collected by the active method of participative research and by investigation of the practices of 120 farms in the commune of Koumbia. Principal component analyses with economic indicators of the EAF were applied, followed by an ascending hierarchical clustering. The structural characteristics, the agro-pastoral practices of production, and the perceptions of the EAF regarding the constraints and appropriateness of agricultural production were compared by variance analysis. Results. The results showed three types of farm: farms with a low-income culture (farmers with few animals), those with a high income culture (farmers with a large number of animals) and those deriving income from breeding (stockbreeders). Taking into account the structure of the farms, their production practices, their technico-economic performance and their appropriateness of agricultural production, the form of sustainable accompaniment needed may be identified in relation to several common or specific innovations of the identified farm types. Accompaniments in the case of farm stock management, and good practice in the management of soil fertility and of animals were common to the three types of EAF. The fodder culture, fattening on pasture and the method of dairy production were specific to the farmers with a large number of animals and to the stockbreeders. The improvement of the food value of culture residues and of some aspects of the maintenance of oxen were more appropriate to the farmers with few animals. Conclusions. In order to succeed, the process of accompaniment must take into account both these specificities and the concept of sustainability. Description du sujet. Dans la zone cotonnière ouest du Burkina Faso, la variabilité et la diversité des revenus des exploitations agricoles familiales (EAF) demandent pour ces dernières des accompagnements appropriés. Objectifs. Cet article rend compte de cette diversité et des besoins d’accompagnement selon les types d’EAF identifiés.Méthode. Les données ont été collectées par la méthode active de recherche participative et par enquête auprès d’un échantillon raisonné de 120 exploitations dans la commune de Koumbia. Une analyse en composante principale avec des indicateurs économiques de l’EAF suivie d’une classification ascendante hiérarchique ont été appliquées. Les caractéristiques structurelles, les pratiques de production agro-pastorales, les perceptions des chefs d’EAF sur les contraintes et opportunités de production agropastorale ont été comparées par une analyse de variance.Résultats. Les résultats montrent trois types d’exploitations : les exploitations à faible revenu culture (agriculteurs), à fort revenu culture (agro-éleveurs) et à revenu élevage (éleveurs). À la lumière de leurs structures, pratiques de production, performances technico-économiques et opportunités de production agricole, leur accompagnement peut porter sur plusieurs innovations durables communes ou spécifiques des types identifiés. Des accompagnements sur la gestion des ressources de l’exploitation, les bonnes pratiques de gestion de la fertilité des sols et des animaux sont communs aux trois types d’EAF. Les cultures fourragères, l’embouche et la production laitière sont spécifiques aux agro-éleveurs et éleveurs. L’amélioration de la valeur nutritive des résidus de cultures et l’entretien des bœufs de trait conviennent plus aux agriculteurs.Conclusions. Pour réussir, le processus d’accompagnement doit prendre en compte ces spécificités et la notion de durabilité.

L'aquaculture est l'une des composantes principales de l'apport en protéines dans le monde, surtout en Asie. Elle croît, alors que la pêche, qu'elle a dépassée en tonnage comme en valeur, décline. Selon les écosystèmes et les méthodes employées, elle peut contribuer à valoriser, mais aussi à dégrader les milieux aquatiques. Dans la zone côtière, espace riche et productif au plan biologique mais convoité, l'aquaculture conserve un potentiel de développement si sa mise en œuvre intègre les principes de la durabilité. Celle-ci peut être éclairée par la prospective avec des méthodes d'analyse adaptées à chaque projet. L'analyse de l'expérience de 33 ans en aquaculture de D. Lacroix est faite en trois temps. D'abord, il s'agit de vérifier la qualité de ses travaux de recherche scientifique menés dans des contextes et avec des responsabilités variés en suivant la grille d'analyse de référence d'un doctorat. Ensuite, l'analyse consiste à prendre un recul critique sur les bilans de réalisations majeures (Antilles, Guyane…) en mobilisant l'approche de M. Callon dont la théorie de la traduction permet de construire le réseau des acteurs et de le projeter dans la problématique. Cette grille d'analyse est complétée par l'étude des aspects de temporalité, légitimité et d'acceptabilité pour chaque réalisation. Ce travail sur diverses situations d'intervention permet de préparer une réflexion sur la proposition méthodologique qui suit et son adaptation à des conditions variables. Enfin, les connaissances acquises sont synthétisées afin de construire une méthode de prospective qui permettrait de gagner en temps, en efficacité et en moyens sur des projets à venir. Pour cela, l'analyse s'appuie sur la vision de R. Passet, qui structure les éléments de tout projet dans la hiérarchie des composantes de la durabilité. Le système dynamique qui en résulte peut être alors croisé avec divers scénarios afin d'en simuler les conséquences et donc d‟éclairer les choix. Cette méthode, dite Aster, est testée sur le cas « modèle » et bien documenté de l'élevage de la crevette Macrobrachium rosenbergii en Guyane française. Elle permet d'aboutir à des recommandations précises et argumentées en matière de recherche comme de développement pour tout décideur impliqué. Aquaculture is one of the main supply of protein in feed for mankind, notably in Asia. It increases and had exceeded the level of production of world fisheries, which is decreasing. According to sites and rearing methods, aquaculture contributes to add value but also in some cases to impact negatively the aquatic ecosystems. In the coastal area, a rich and productive zone, but also a place of conflicts, this activity presents a high potential for development if it takes into account the rules of sustainability. The conditions of this sustainability may be cleared with appropriate methods of foresight analysis applied for each development project. The analysis of the professional experience of D. Lacroix for 33 years in aquaculture is structured in three steps. Firstly, the work is to check the scientific value of the research conducted under his responsibility in various contexts and for different responsibilities. This study refers to the requirements of a PhD. In the second part of the work, the results of few major projects (French West Indies, French Guyana….) are analysed with the support of the theory of translation (Callon et al) which allows to build a network of actors and to project it into the context. This way of study includes a special attention to the aspects of time planning, legitimacy and acceptability. Finally, the author examines how this knowledge gained from experience could help building a method for foresight analysis aiming at a shorter planning, a better timing and less means for future projects. To achieve this goal the author integrates the vision of the economist R. Passet which structures any project in an ecosystemic framework, including criteria of sustainability. The mix of these two approaches (Callon & Passet) entails in a new tool for foresight analysis, called Aster, which originality is to offer the possibility to test various scenarios and related consequences to help decision -makers. This new method of foresight analysis, is then tested on the well known case study of the development of prawn Macrobrachium rosenbergii in French Guyana. The test shows to be successful as it delivers precise and arguable recommendations about research and development for all stakeholders.

[ES] Este trabajo presenta una parte de los resultados obtenidos durante el proyecto de cooperación internacional PIRAGUA (EFA210/16), co-financiado por el Programa Interreg EFA (España-Francia-Andorra). Entre 2018 y 2021, el proyecto PIRAGUA abordó, mediante la cooperación transfronteriza, la evaluación del ciclo hidrológico y los recursos hídricos en los Pirineos, en el presente y en futuro, en el contexto del cambio climático. Para ello, los socios del proyecto unificaron y homogeneizaron la información hidrológica existente, propusieron indicadores hidrológicos, analizaron las tendencias observadas en dichos indicadores, desarrollaron modelos de simulación para conocer en detalle los distintos componentes del balance hídrico, y realizaron simulaciones numéricas a partir de proyecciones climáticas bajo distintos escenarios de emisiones de gases de efecto invernadero para evaluar las consecuencias del cambio climático sobre el ciclo hidrológico y los recursos hídricos de los Pirineos. El objetivo de este volumen es realizar una caracterización de los recursos hídricos superficiales y subterráneos de los Pirineos, así como de la gestión y uso de dichos recursos (Capítulo 1); analizar los registros de caudal, niveles de acuíferos e inundaciones para determinar patrones espaciales y determinar las tendencias temporales observadas en las últimas décadas (Capítulo 2); aplicar herramientas de simulación para ampliar el conocimiento sobre los distintos componentes del balance hídrico de los Pirineos (Capítulo 3); y realizar una serie de experimentos de simulación numérica para determinar los posibles cambios del balance hídrico y los recursos hídricos de los Pirineos a lo largo del siglo XXI, en un contexto de cambio climático (Capítulo 4). [FR] Ce travail présente une partie des résultats d'un projet de coopération internationale du Programme Interreg EFA (Espagne-France-Andorre). Entre 2018 et 2021, le projet PIRAGUA (EFA210/16) a abordé, par le biais de la coopération transfrontalière, l'évaluation du cycle hydrologique et des ressources hydriques dans les Pyrénées, pour le présent et l'avenir, dans le contexte du changement climatique. Pour cela, les partenaires du projet ont unifié et homogénéisé les informations hydrologiques existantes, proposé des indicateurs hydrologiques, analysé les tendances observées pour ces indicateurs, développé des modèles de simulation pour connaître les détails du bilan hydrique et réalisé des expériences de simulation numérique, afin d'évaluer les conséquences de scénarios de changement climatique sur le cycle hydrologique et les ressources hydriques des Pyrénées. L'objectif de ce volume est de réaliser une caractérisation des ressources hydriques de surface et souterraines des Pyrénées, de la gestion et de l'emploi des ressources (Chapitre 1) ; analyser les registres de débit, le niveau des aquifères et les inondations afin de déterminer des schémas spatiaux ainsi que les tendances temporelles observées ces dernières décennies (Chapitre 2) ; appliquer des outils de simulation pour réaliser un diagnostic des différents éléments du bilan hydrique des Pyrénées (Chapitre 3); réaliser une série d'expériences de simulation pour déterminer les éventuels changements du bilan hydrique et des ressources hydriques des Pyrénées tout au long du XXIᵉ siècle, dans un contexte de changement climatique (Chapitre 4). [EN] This volume presents part of the results obtained during the international cooperation project PIRAGUA (EFA210/16), co-financed by the Interreg EFA Program (Spain-France-Andorra). Between 2018 and 2021, the PIRAGUA project addressed, through cross-border cooperation, the evaluation of the hydrological cycle and water resources in the Pyrenees, in the present and in the future, in the context of climate change. To do this, the project partners unified and homogenized the existing hydrological information, proposed hydrological indicators, analyzed the trends observed in said indicators, developed simulation models to know in detail the different components of the water balance, and carried out numerical simulations based on projections under different scenarios of greenhouse gas emissions to assess the consequences of climate change on the hydrological cycle and the water resources of the Pyrenees. The objective of this volume is to carry out a characterization of the surface and underground water resources of the Pyrenees, as well as the management and use of said resources (Chapter 1); analyze flow records, aquifer levels, and floods to determine spatial patterns and determine temporal trends observed in recent decades (Chapter 2); apply simulation tools to expand knowledge about the different components of the water balance of the Pyrenees (Chapter 3); and carry out a series of numerical simulation experiments to determine possible changes in the water balance and water resources of the Pyrenees throughout the 21st century, in a context of climate change (Chapter 4). This report was developed within the project EFA210/16 PIRAGUA (“Evaluación y prospectiva de los recursos hídricos de los Pirineos en un contexto de cambio climático, y medidas de adaptación con impacto en el territorio / Evaluation et prospective des ressources en eau des Pyrénées dans un contexte de changement climatique, et mesures d’adaptation avec un impact sur le territoire”), co-funded by the European Regional Development Fund (ERDF) through the Interreg V-A Spain France Andorra program (POCTEFA 2014-2020) (65%) and the project’s partners: CSIC, UPV/EHU, UB, OE, IGME, CNRS, BRGM, INRAE and OBSA (35%). [FR] Un fichier PDF avec la version pré-imprimée du document; [EN] One PDF files with the pre-print version of the document; [ES] Un archivo PDF con la versión de pre-impresión del documento. Peer reviewed

The species composition and spatial distribution of macrofaunal assemblages in intertidal sands of Arcachon Bay, on the southwestern Atlantic coast of France, were investigated through a quantitative sampling of twenty stations representative of the various sandy habitats found in the bay, excluding the exposed beaches. Sampling was done on a single occasion, during the winter of 1988. A total of 150 macrobenthic species (> 1 mm) were collected. The abundance of macrofauna ranged from 89 to 52000 ind.m-2 (with a high dominance of the gastropod Hydrobia ulvae in some sites) and the biomass ranged from 1.3 to 42.5 g.m-2 dry weight. Thirteen additional species (belonging to temporary meiofauna and small macrofauna) were also sampled in the sieving fraction comprised between 1 mm and 100 mum. In this size fraction, the highest densities were those of H. ulvae juveniles in the inner bay and the small polychaete Parapionosyllis gestans in the outer bay. Mean abundance of total fauna > 100 mum (excluding permanent meiofauna) was about 35000 ind.m-2 in both sheltered and semi-exposed stations. A correspondence analysis of the distribution of species among stations followed by an automatic hierarchical classification identified six benthic assemblages, which were also characterized in terms of species dominance, constancy and fidelity. Two assemblages, corresponding to the boreal Macoma community, were distinguished in the sands at mid-tide level in the inner part of the bay: station-group A was characterized by Neomysis integer and Streblospio shrubsolii, together with a low number of species occurring in low-salinity estuarine waters; station-group B, with Cerastoderma edule, Arenicola marina, and Nereis diversicolor as characteristic species, was a sandy facies of the Macoma community dominated by C. edule. Three other assemblages, each with a high species richness, included several species of the boreal Lusitanian Tellina community: station-group C: a Eunice vittata-Tubificoides benedeni assemblage at lower tidal levels in the central part of the bay; station-group D: a Ruditapes decussatus-Goniada emerita assemblage at mid-tidal levels of the outer bay; station-group E: an Echinocardium cordatum-Magelona mirabilis-Aonides oxycephala assemblage at lower tidal levels of the outer bay. A sixth assemblage (station-group F) was an Ophelia bicornis-Bathyporeia sarsi assemblage in fine dune sands of the outer bay. A discriminant analysis including five environmental variables (tidal level, salinity, sediment median, fine particles and organic contents) revealed the first two variables to be the most important factors in the ordination of stations. With these five variables, only 65 % of the stations were correctly classified in the station-groups identified by correspondence analysis. Among the other possible factors governing the distribution of benthic assemblages, the importance of both exposure and circulation of water masses is stressed. Sheltered stations had a mean biomass of 22.8 g.m-2 dry weight and a mean species richness of 17.7 species; in semi-exposed stations, these values were 11.5 g.m-2 dry weight and 36.1 species.

Aquaculture is an economic activity which is characterised by a great dependence on environmental conditions. Therefore aquaculture development is subdued to institutional context which defines the rules for use and conservation of the environment. This paper analyses the impact of marine environment regulations on economic operating of aquaculture enterprises and on industrial dynamics. Because aquaculture enterprises use a collective good, an economic approach of aquaculture has to take into account not only the relations between enterprises and environment, but also the relations between the enterprises themselves, through production externalities. In this study, several economic tools are considered in order to incite enterprises to integrate pad of the cost of their effects on the environment. But these public policies have to take into account the youth of the activity, the specific economic situation of the enterprises and the place of aquaculture in global coastal management. [NOT CONTROLLED OCR] L'aquaculture est confrontée à un cadre institutionnel définissant les conditions d'accès d'utilisation et de protection du milieu marin. La réglementation sur l'environnement va avoir un impact sur le fonctionnement économique des entreprises et sur la dynamique sectorielle de l'aquaculture. A partir de l'étude de la nature des relations entre entreprises et milieu, on peut proposer un certain nombre d'outils économiques permettant de faire prendre en compte par les entreprises une partie du coût de leurs effets sur l'environnement. Dans le cas particulier de l'aquaculture marine, cette réglementation doit cependant tenir compte de la jeunesse de l'activité, de la situation économique des entreprises et de leur rôle dans une politique d'aménagement du littoral. [OCR NON CONTRÔLE]

On the bathyal slope for continental margins, steep and rocky substrates punctuated with cliffs and collapsing zones are frequently found. As survey and sampling with the classical technics from the sea surface is practically impossible in such an environment, in situ exploration with a submersible allows significant advances in ecology, with implications in paleoenvironment reconstruction. Mixing of material from shallow-water and deep-sea origins into bathyal sedimentation suggests that the so-called "fossil assemblages of outer platform" were frequently misinterpreted. Dense populations of animals closely related to fossil groups which were only considered as relict of the Past ("living fossils") and previously interpreted as shallow-water inhabitants during geological times can be discovered living in such bathyal communities. The role of bathyal ecological niches during global bioevents brings a new vision of the history of life in the Ocean through geological time and has to be further investigated. Examples from cruises monitoring the diving saucer Cyana (SP 3000) in the Bay of Biscay and off New Caledonia are given.

The primary production (phytoplankton and microphytobenthos) of a coastaL shallow water ecosystem (0.5 m) was investigated in two sandy areas, differing by their wave exposure. The physical and chemical parameters, the functional chlorophyll and pheopigments as well as the primary production were measured monthly, throughout a two-year study. The bivalve Ruditapes decussatus was the dominant species in the sheltered station (RD), whereas Donax trlmcu/us inhabited the other station (DT) which was exposed to the open-sea waves. Microphytic biomasses were determined after extracting chlorophyll a and pheopigments in 90% acetone. by spectrophotometric measurements before and after acidification. Gross hourly primary production was estimated by measuring the oxygen balance in light and dark enclosures. The mlcrophytobenthos was considered in the upper centimetre. The main characteristics of the water. temperature. salinity and dissolved oxygen were more variable in the sheltered area; the redox potential was generally lower in this sediment and the vertical profile revealed a "redox potential discontinuity"• which usually did not appear in the open site. In the water column (phytoplankton seasonal fluctuations were similar in both stations. The annual average values of Chla and primary production were equivalent (1.40±0.56 and 1.94±078 mg Chla.m2: 19.60±11.09 and 20.29±8.45mgCm- 2.h- 1 in RD and DT respectively). On the other hand. for the microphytobenthos. the autumn blooms were more pronounced in the sheltered station (RD) than in the wave-exposed one (DT). The annual average value of the biomass (ChIa in upper cm of sediment) was Il times higher at the RD than the DT station (42.89 ± 6.86 and 3.87 ± 1.84 mg Chla.m• 2) and the annual average of primary production 4 limes higher (19.94±6.13 and 4.77 ± 3.12 mgC m-2 .h-1). The benthic biomass was 30 times higher at the sheltered station (RD) than the planktonic one. whereas the primary production values were similar. In the wave-exposed station (DT), the benthic biomass was only twice that of the planktonic one and the planktonic primary production 4 times higher than the benthic one. The P/E ratios (assimilation numbers) indicated a better efficiency at the planktonic level [14 mgC(mg ChIa) -1.h-1 for the sheltered site and 10.46 for the open station]. They were only of 0.46 and 1.23 mgC(mg Chla) -1 - h-1 for the benthos. Such results revealed that the primary production did not exhibit the same difference between the two stations as the chlorophylI A correlation analysis gave evidence of strong relationships between both stations for the pelagic parameters, but no correlations were found between the two sites at the benthic level. When considering the primary producers (plankton + benthos) as a whole. the sheltered station was richer and more productive than the wave-exposed one. The waters were similar in both sites. indicating a common origin, but the productivity was more important in the sheltered area. due to the richness of the benthic microflora On a comparé durant deux années la biomasse (Chla fonctionnelle) et la production primaire (bilans d'oxygène) des microphytes benthiques et planctoniques de deux plages de sables fins (0,5 m de profondeur), soumises à des conditions hydrodynamiques différentes. La station de mode calme (RD) abrite notamment un peuplement de Ruditapes decussatus (pélécypode) tandis que la station de mode agité (DT) soumise à l'influence du large, est habitée par des peuplements d'un autre pélécypode, Donax trunculus. Dans le compartiment pélagique (phytoplancton) les variations saisonnières sont à peu près identiques dans les deux stations. Les moyennes annuelles de la biomasse et de la production primaire sont sensiblement équivalentes (1.40 ± 0,56 et 1,94 ± 0,78 mg Chla.m - 2: 19,60 ± 11.09 et 20,29 ± 8.45 mgc.m - 2.h -1 respectivement en RD et DT). En revanche, dans le compartiment benthique (microphytobenthos), des floraisons d'automne sont plus accentuées à la station de mode calme (RD) qu'à la station de mode agité (DT). La moyenne annuelle de biomasse (1er cm d'épaisseur du sédiment) est Il fois plus élevée à la station RD qu'à la station DT (42,89 ± 6,86 et 3,87 ± 1,84 mg Chla.m- 2) et la moyenne de la production primaire 4 fois supérieure (19,94 ± 6,13 contre 4,77 ± 3,12 mgC.m- 2.h- 1). Dans la station RD (calme), la biomasse benthique (1er centimètre) est 30 fois supérieure à la biomasse planctonique, alors que les productions primaires sont équivalentes. Dans la station de mode agité (DT) la biomasse benthique est seulement double de la biomasse planctonique et la production primaire planctonique est 4 fois supérieure à la production benthique. L'étude des corrélations montre que des liaisons étroites existent entre les deux stations pour les paramètres du domaine pélagique, alors que dans le domaine benthique, les moyennes et les évolutions sont différentes dans les deux sites. La station de sables fins de mode calme est, au total. à l'échelon primaire (plancton + benthos), plus riche et plus productive que la station de mode agité.