• Energy Research
• 15. Life on land close
• 11. Sustainability close
• FR close
• US close
• GB 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.

Metadata only record This document presents an analysis of Fulani pastoral farming systems that focuses on how pastoralists use silvopastoral land. It aims to provide the missing knowledge needed to implement the resource management ('gestion des terroirs') approach at village level. In this region the influence of pastoral land use on the environment appears to be less pronounced than that of crop cultivation, even though levels of animal production are reasonable. The carrying capacity of the region has not yet been attained. Current constraints to pastoral land use in the region arise from the encroachment of cropland at the expense of pastoral land, and the increase in animal numbers. To develop sustainable natural resource management at village level that includes Fulani pastoral land use, the key factors appear to be the integration of livestock husbandry and cropland cultivation at household level, agreements between pastoralists and cropland farmers on land tenure and resource management, and support targeting of Fulani households (which have so far been neglected). Specific recommendations are given. (CAB Abstract)

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.

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.

Description du sujet. La baisse et l’irrégularité des pluies modifient considérablement les saisons culturales, ce qui oblige les paysans à une restructuration du calendrier agricole en s’appuyant sur les savoirs locaux. Objectifs. L’objectif de cette étude est de valoriser les savoirs locaux utilisés par les paysans dans la gestion du calendrier agricole. Les objectifs spécifiques sont, d’une part, d’inventorier les indicateurs biophysiques utilisés dans la définition des calendriers culturaux et, d’autre part, de déterminer les espèces végétales repères communes aux trois zones écologiques étudiées. Méthode. Ce but fut atteint grâce à des interviews semi-directes individuelles et via des focus groups auprès d’un échantillon de 689 agriculteurs répartis dans 65 localités. Résultats. Il ressort que la totalité des paysans enquêtés utilisent des marqueurs temporels dans la définition des calendriers culturaux, surtout dans la reconnaissance des débuts de saison pluvieuse (période de semis) et de saison sèche (période de récolte). Il s’agit principalement des indicateurs biologiques tels que la phénologie des plantes (en saison sèche : Triumfetta rhomboidea Jacq. [floraison], Spathodea campanulata P.Beauv. [floraison], Vitellaria paradoxa C.F.Gaertn. [fructification] et en saison pluvieuse : Millettia thonningii (Schum. & Thonn.) Baker [floraison], V. paradoxa [floraison], Delonix regia (Hook.) Raf. [floraison], Ceiba pentandra (L.) Gaertn. [éclatement du fruit]). Au total, 67 espèces végétales ont été recensées comme indicateurs des variations des saisons agricoles. Outre les espèces végétales, la migration saisonnière des oiseaux (73 %), l’apparition des insectes (48 %), mais aussi des indicateurs abiotiques comme le sens du vent (100 %), les observations des étoiles (82 %) et le déplacement des nuages (69 %) sont utilisés comme repères dans la gestion des périodes agricoles. Conclusions. La connaissance de ces signaux permet aux paysans d’anticiper sur d’éventuelles variabilités climatiques et suivre, diriger et adapter leurs activités culturales. Ces savoirs locaux constituent dès lors une aubaine pour l’adaptation aux changements climatiques.

From Rio to Rio: A global carbon price signal to escape the great climate inconsistency Two decades after the 1992 Rio Conference,we must admit to collective failure in combating human induced climate change. We cannot escape serious climate disruption if we keep going down that road. We must change direction, and we must move quickly. To this end, we call in this paper for a fine tuning of the international negotiations on climate. We propose refocusing these international efforts on negotiating a global carbon price signal, harmonized in principle but flexible in practice, instead of doggedly spending the next few years attempting to convince countries to accept stricter national targets for quantitative reduction of their greenhouse gas (GHG) emissions.

Metadata only record The paper proposes a theory of technology development for semi-arid regions. It then evaluates the theory by reviewing the characteristics of technologies successfully introduced into the regions. Modeling is then used to identify some constraints to further technology introduction of the type proposed. Some specific policy recommendations to accelerate technology introduction are made.

This article sheds light on the issue of financing the 2030 Agenda. First of all, we highlight the analytical inconsistency of market financing strategies based on neoclassical theory. We then put forward the elements of an alternative strategy based on the issuance of a new category of financial instruments: the ecological sovereign security (ESS). Then, we develop "Philia 1.1", a new 32-equation stock-flow coherent model (SFC) to analyze the effects of issuing TSE on macroeconomic dynamics and the ecological transition process. Simulations suggest that the issuance of TSEs could help to drive an expansionary macroeconomic dynamic beneficial to employees, while embedding the additional activity in new ecological and social criteria. TSE emissions could therefore play a driving role in the pursuit of Sustainable Development Goals (SDGs). Cet article apporte l’éclairage de la Théorie Financière Écologique sur la question du financement de l’Agenda 2030. Nous mettons en évidence l’incohérence analytique du financement par les marchés, fondé sur la théorie néoclassique. Nous avançons une stratégie alternative reposant sur l’émission d’une nouvelle catégorie d’instruments financiers : le titre souverain écologique (TSE). Puis, nous développons « Philia 1.1 » un nouveau modèle stock-flux cohérent. Les simulations suggèrent que l’émission de TSE pourrait impulser une dynamique macroéconomique expansionniste bénéfique aux salariés tout en encastrant le surcroit d’activité dans de nouveaux critères écologiques et sociaux. L’émission de TSE pourrait jouer un rôle moteur dans la poursuite des Objectifs du Développement Durable (ODD).

Eco-anthropology in Lower Loire river : collectives to the test of the tide, the mild, the dry At the mouth of the Loire, from the upstream of Nantes to Saint-Nazaire, the floodplain is composed of various wetlands. This area is the site of many marshland activities, subject to the hazards of the "last wild river in Europe" : variations in discharge, tides, sedimentary and biological flows. Eco-anthropological research is currently underway in this area, aimed at describing some practices and uses, and their place in the effective management of the Lower Loire ecosystem. The research approach is inspired by a symmetrical anthropology that leaves place for non-humans, considering a hybrid sociality in which the categories of nature and culture are set aside. It is based mainly on ethnographic materials acquired during field surveys. Through this paper, we pay attention to the ways in which some of the collectives are recomposed. These assemblages are tested by the increase in the oscillating volume of the tide induced by the intensification of dredging in the estuary since 1976, as well as by the consequences of the episode of mild winter weather and insufficient rainfall, particular to the 2016-1017 period. We think that the « mere description » of these singular relations is a way of co-producing knowledge with the beings of these hybrid collectives, and that reporting it may strengthen their consistency. We present a table of different modes of coexistence of these collectives of things, beasts, humans and plants in the trial of strength of the Capitalocene, and conclude by emphasizing the necessity to develop there a relational ecology through the practice of an « art of attention ». Keywords : eco-anthropology, Loire estuary, Brière, Brivet, hybrid collectives, low water, climate change, planning, Capitalocene À l'embouchure de la Loire, de l'amont de Nantes à Saint-Nazaire, le lit majeur du fleuve est composé de diverses zones humides. Cet espace est le lieu de nombreuses activités palustres, soumises aux aléas du fleuve : variations de débits, marées, flux sédimentaires et biologiques. Une recherche éco-anthropologique est actuellement en cours sur cet espace, visant à décrire certaines pratiques et certains usages, et leur place dans la gestion effective de l'écosystème de la Basse-Loire. La démarche de recherche s'inspire d'une anthropologie symétrique laissant la place aux non-humains, considérant une socialité hybride où les catégories de nature et de culture sont mises de côté. Il s'appuie principalement sur les matériaux ethnographiques acquis lors d'enquêtes de terrain. Dans cet article, nous prêtons attention aux évolutions de ces agencements face à l‘augmentation du volume oscillant de la marée induit par l'intensification des dragages de l'estuaire depuis 1976, ainsi qu'aux effets de l'épisode de douceur hivernale et de déficit pluviométrique particulier à la période 2016-1017. Nous pensons que la « simple description » de ces relations singulières est un mode de co-production du savoir avec les êtres qui peuplent ces collectifs hybrides, et que le fait d'en rendre compte est susceptible de renforcer leur cohérence. Nous présentons un tableau de différents modes de coexistence de ces collectifs de choses, de bêtes, d'hommes et de plantes à l'épreuve du Capitalocène, et concluons en soulignant la nécessité d'y développer l'écologie des relations par la pratique d'un « art de l'attention ». Mots-clés : éco-anthropologie, estuaire de la Loire, Brière, Brivet, étiage, changement climatique, aménagement, collectifs hybrides, Capitalocène