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Contexte : Malgré des be- soins toujours plus pressants de trouver des alternatives aux produits phytopharmaceutiques, force est de constater que le secteur des macro-organismes de biocontrôle peine à se généraliser dans la pratique et, avant tout, à s'imposer dans l'esprit des parties intéressées : les utilisateurs finaux (les agriculteurs), les conseillers techniques, mais également les politiques et les financeurs. Stratégies de lutte : La régulation des bioagresseurs peut se réaliser en favorisant les individus déjà présents dans ou aux alentours des parcelles cultivées : c'est ce que l'on appelle la lutte biologique par conservation. Elle peut également se faire en introduisant certains auxiliaires délibérément dans les parcelles cultivées (acclimatation, augmentation, lutte autocide). Cet article présente les stratégies de biocontrôle à l'aide de macro-organismes (essentiellement des insectes, acariens ou nématodes entomopathogènes), qu'elles soient pratiquées depuis longtemps en France, plus récemment implantées, voire encore prospectives.

The evolutionary reason why many animals display color changes remains a key question. Solving it requires an integrative understanding of the biological significance of colors. In this work, I investigate the structure–function relationship of color-changing ommochrome pigments and their organelles using analytical chemistry, quantum modelling and subcellular multimodal imaging. This interdisciplinary approach reveals that the photochemical and intracellular bases of ommochromes determine both their color-changing capacities and their chemical reactivity, among other pleiotropic functions. My results support the idea that color changes of ommochromes are a multiscale property that affects biologically relevant functions besides coloration, such as redox and metal homeostasis.; L’évolution de la capacité à changer de couleur chez les animaux est un sujet majeur. Son étude requiert une compréhension intégrée de l’importance biologique des couleurs. Dans ces travaux, j’explore la relation structure–fonction, en termes de changement de couleur, des pigments appelés ommochromes et de leurs organites. J’utilise pour cela la chimie analytique, la modélisation quantique et l’imagerie multimodale à l’échelle subcellulaire. Cette approche interdisciplinaire révèle que les bases photochimiques et intracellulaires des ommochromes déterminent, à la fois, leurs capacités à changer de couleur et leur réactivité chimique. Mes résultats renforcent l’idée que les changements de couleur des ommochromes sont une propriété multi-échelle qui a des effets sur des fonctions biologiques au-delà de la coloration, comme l’homéostasie redox et métallique.

Little is known regarding how trophic interactions shape community assembly in tropical forests. Here we assess multi-taxonomic community assembly rules using a rare standardized coordinated inventory comprising exhaustive surveys of five highly-diverse taxonomic groups exerting key ecological functions: trees, fungi, earthworms, ants and spiders. We sampled 36 1.9-ha plots from four remote locations in French Guiana including precise soil measurements, and we tested whether species turnover was coordinated among groups across geographic and edaphic gradients. All species group pairs exhibited significant compositional associations that were independent from soil conditions. For some of the pairs, associations were also partly explained by soil properties, especially soil phosphorus availability. Our study provides evidence for coordinated turnover among taxonomic groups beyond simple relationships with environmental factors, thereby refining our understanding regarding the nature of interactions occurring among these ecologically important groups.

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Prioritization of introduction pathways is seen as an important component of the management of biological invasions. We address whether established alien plants, mammals, freshwater fish and terrestrial invertebrates with known ecological impacts are associated with particular introduction pathways (release, escape, contaminant, stowaway, corridor and unaided). We used the information from the European alien species database DAISIE (www.europe-aliens.org) supplemented by the EASIN catalogue (European Alien Species Information Network), and expert knowledge. Plants introduced by the pathways release, corridor and unaided were disproportionately more likely to have ecological impacts than those introduced as contaminants. In contrast, impacts were not associated with particular introduction pathways for invertebrates, mammals or fish. Thus, while for plants management strategies should be targeted towards the appropriate pathways, for animals, management should focus on reducing the total number of taxa introduced, targeting those pathways responsible for high numbers of introductions. However, regardless of taxonomic group, having multiple introduction pathways increases the likelihood of the species having an ecological impact. This may simply reflect that species introduced by multiple pathways have high propagule pressure and so have a high probability of establishment. Clearly, patterns of invasion are determined by many interacting factors and management strategies should reflect this complexity

The dramatic decline of invertebrates at a global scale is mainly driven by habitat loss, agricultural intensification and urbanization. Alley cropping agroforestry is a land use practice in which arable crops are grown between tree rows. In such systems, understory vegetation strips (UVS) develop in the tree rows, providing habitats undisturbed by soil tillage. We investigated whether UVS are major overwintering habitats for invertebrates. We focused on carabid communities, which are dominant beneficial invertebrates in crop fields, but suffer from agricultural intensification. We described carabid communities with functional traits related to sensitivity to agricultural disturbances and ecological functions (i.e. pest control). Sampling of invertebrates were carried out from February to June 2018 over seven agroforestry fields in Restinclieres Estate (South France), one of the oldest experimental sites in Europe. The study revealed that 55% of invertebrate taxonomic groups were more abundant in UVS, whereas only 14% were more abundant in crop alleys. Crop pests were overwintering mainly in crop alleys while beneficial invertebrates were more dependent on UVS. Finally, UVS hosted carabids sensitive to agricultural disturbances, characterized by large body length, predominantly granivorous diet and overwintering in adult stage. On the other hand, crop alleys were home to smaller carnivorous species overwintering in both larval and adult stages, which can tolerate high levels of disturbance. Environmental and agricultural policies should consider agroforestry systems, especially understory vegetation strips, as valuable habitats for biodiversity conservation and biological control in agricultural landscapes.

International audience; In the present study, we investigated the efficiency of additional wastewater treatment based on powdered activated carbon and its benefit for the ecosystem of a connected river system in the catchment area of Lake Constance, Southern Germany. We focused on the overall health status of gammarids and the integrity of the macrozoobenthic community. Samples were taken up- and down-stream of a wastewater treatment plant (WWTP), as well as before and after its upgrading. The investigations showed that both sex ratio and fecundity of gammarids, as well as the macrozoobenthic community were affected by the effluent prior to the WWTP upgrade. After the upgrade, gammarids from the downstream site did not differ any longer from those collected upstream of the WWTP with respect to the investigated health parameters. Furthermore, the overall number of taxa and, particularly, the number of sensitive taxa within the macrozoobenthic community downstream of the WWTP increased considerably. Therefore, we conclude that the additional treatment with powdered activated carbon was highly efficient to improve invertebrate health and community integrity.

Les études portant sur les émotions chez les vertébrés, les mammifères en particulier, sont abondantes et bien documentées. Toutefois, bien qu’on s’y intéresse de plus en plus, les émotions des invertébrés, elles, suscitent moins l’attention. À telle enseigne que, bien qu’ils composent 97 % du règne animal, les invertébrés sont les grands laissés-pour-compte des études sur la nature et les fonctions de leurs émotions (Willmer, 1990). Tout en donnant écho aux rarissimes études déjà réalisées, nous avons tenté au travers le présent mémoire de dissiper le doute quant à l’existence des émotions chez les invertébrés par deux moyens principaux : d’une part, en étudiant les émotions en tant qu’états émotionnels primaires ou émotions primitives, dépourvus de la dimension subjective normalement rattachée à l’étude des émotions et d’autre part, en analysant les circuits neuronaux, neurotransmetteurs et hormones, ainsi que les patrons d’expression comportementale typiquement associés aux émotions humaines. À travers cette nouvelle façon de conceptualiser les émotions, nos résultats suggèrent que les systèmes émotionnels neuronaux des vertébrés et invertébrés sont possiblement le fruit d’une évolution commune, qui aurait bifurquée il y a des millions d’années. En conséquence, nous concevons les états émotionnels comme universaux et présents dès la naissance., Studies of emotions in vertebrates, especially in mammals, are abundant and well documented. While researchers have expressed a growing interest to study emotions in invertebrates, they generally attract less attention. Although they account for 97% of the animal kingdom, the nature and functions of emotions in invertebrates have been largely overlooked (Willmer, 1990). By relating the rare studies that have been carried out by researchers, this thesis is meant as an attempt to dispel the doubts surrounding the existence of emotions in invertebrates by essentially two means: firstly, by studying emotions as central emotional states or emotion primitives, devoid of the subjective dimension as a defining feature of emotional process; and secondly, by analyzing the neuronal circuits, neurotransmitters and hormones, together with the behavioral patterns typically linked to emotions as a whole. Through this new conceptualization of emotions, our findings suggest that the neural correlates of emotions in vertebrates and invertebrates are possibly the result of a common evolution, which would have diverged millions of years ago. Thus, we promote emotion states as innate and universal throughout the animal kingdom.

International audience; The first French-Swiss workshop on ecotoxicology of freshwater sediment communities was co-organized by the French Research Institute of Science and Technology for Environment and Agriculture (Irstea) and the Swiss Centre for Applied Ecotoxicology (Ecotox Centre EAWAG-EPFL) in Villié-Morgon (Beaujolais Region, France) on April 27-28, 2017. The workshop brought together scientists working in different fields of expertise (ecotoxicologists, ecologists, environmental chemists...), environmental stakeholder groups and managers, as well as economic players (start-ups and consultancies) to better connect research needs of potential end-users with research outputs. The objectives of this workshop were (i) to establish the state of the art of research in the characterization of sediment contamination and in the evaluation of the effects on sediment-associated biological communities and ecosystem functioning and (ii) to give an overview of the French and Swiss regulations dealing with the assessment of contaminated sediments in freshwater ecosystems. The ultimate goal was to collectively identify research needs and knowledge gaps, as well as to highlight ways to improve the ecotoxicological assessment of sediments in freshwater environments by further considering the structure and functions of associated microbial and invertebrate communities.

/ Le poster décrit les étapes de développement d'un nouvel outil, le ToxMate, qui permet de suivre en temps réel et de façon autonome la qualité toxique d'une eau traitée. Cet outil s'appuie sur l'analyse en continu du comportement locomoteur d'invertébrés, connu pour sa grande sensibilité aux contaminants. Après une phase de développement d'une méthodologie reproductible au laboratoire, l'outil a été déployé en condition réelle en sortie de traitement secondaire de station d'épuration.

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International audience; Sediments play a critical role in biogeochemical cycling and in the maintenance of the biodiversity. They are natural sinks for many contaminants which can accumulate over time and impact exposed communities, thereby disturbing the functioning of aquatic ecosystems. However, knowledge about the functional effects of contaminants on benthic communities is scarce and there is a need of ecosystem functioning indicators of ecotoxicological impacts. In the present microcosm study, we assessed the individual and combined effects of Cu and As (40 mg kg dw-1 each, 21 days of exposure) on the capacity of natural micro- and macro-organism communities from an uncontaminated river sediment to consume and decompose particulate organic matter using the bait lamina method (ISO 18311) as well as artificial tablets consisting of cellulose, bran flakes and active coal embedded in an agar matrix. The sediment toxicity was also evaluated using the standardized ostracod toxicity test (ISO 14371:2012). The two tested substrates (i.e. bait lamina and artificial tablets) showed similar results with low effects of As on feeding activity and organic matter breakdown whereas Cu demonstrated a strongest functional effect. When the two metals were combined, a total functional inhibition was observed, whatever the kind of substrate. The ostracod toxicity test also showed high toxicity of Cu-spiked and mixture-spiked sediments and low toxicity of As-spiked sediments. Our results highlight the relevance of artificial organic matter substrates to assess the functional effects of contaminants on sediment micro- and macro-organism communities, opening new perspectives to assess the functional integrity of contaminated sediments.

The ecotoxicity of different carbon-based nanoparticles (CNPs) was assessed in freshwater organisms, especially in Xenopus laevis. The surface of the CNPs was shown to be the more relevant parameter to describe the growth inhibition in Xenopus, regardless of their allotropic form and their state of dispersion. Micronucleus induction was also studied in Xenopus and graphene oxide (GO) was found genotoxic at low dose. This result was in compliance with the study of genes expression. The involved toxicity mechanisms would be related to the oxidized functions of the CNP. Moreover, GO was also found responsible for genotoxicity in Pleurodeles waltl. and for teratogenicity, development delay and growth inhibition in Chironomus riparius. These organisms have finally been put together in a mesocosm, which has also led to genotoxicity in Pleurodeles in the presence of GO.; L'écotoxicité de différentes nanoparticules de carbone (NPC) a été évaluée chez des organismes aquatiques, en particulier chez Xenopus laevis. Il a été montré que la surface des NPC est le paramètre le plus pertinent pour décrire l'inhibition de croissance chez le xénope, indépendamment de leur forme allotropique et de leur état de dispersion. L'induction des micronoyaux a aussi été étudiée chez le xénope, et l'oxyde de graphène (GO) s'est révélé génotoxique à faible dose, résultat corroboré par l'étude de l'expression des gènes. Les mécanismes de toxicité impliqués seraient notamment liés aux fonctions oxygénées de la particule. De plus, le GO a aussi entrainé de la génotoxicité chez Pleurodeles waltl. et de la tératogénicité, des retards de développement et de l'inhibition de croissance chez Chironomus riparius. La mise en interaction de ces organismes au sein d'un mésocosme a également conduit à l'observation de génotoxicité chez le pleurodèle en présence de GO.

The ecotoxicity of different carbon-based nanoparticles (CNPs) was assessed in freshwater organisms, especially in Xenopus laevis. The surface of the CNPs was shown to be the more relevant parameter to describe the growth inhibition in Xenopus, regardless of their allotropic form and their state of dispersion. Micronucleus induction was also studied in Xenopus and graphene oxide (GO) was found genotoxic at low dose. This result was in compliance with the study of genes expression. The involved toxicity mechanisms would be related to the oxidized functions of the CNP. Moreover, GO was also found responsible for genotoxicity in Pleurodeles waltl. and for teratogenicity, development delay and growth inhibition in Chironomus riparius. These organisms have finally been put together in a mesocosm, which has also led to genotoxicity in Pleurodeles in the presence of GO.; L'écotoxicité de différentes nanoparticules de carbone (NPC) a été évaluée chez des organismes aquatiques, en particulier chez Xenopus laevis. Il a été montré que la surface des NPC est le paramètre le plus pertinent pour décrire l'inhibition de croissance chez le xénope, indépendamment de leur forme allotropique et de leur état de dispersion. L'induction des micronoyaux a aussi été étudiée chez le xénope, et l'oxyde de graphène (GO) s'est révélé génotoxique à faible dose, résultat corroboré par l'étude de l'expression des gènes. Les mécanismes de toxicité impliqués seraient notamment liés aux fonctions oxygénées de la particule. De plus, le GO a aussi entrainé de la génotoxicité chez Pleurodeles waltl. et de la tératogénicité, des retards de développement et de l'inhibition de croissance chez Chironomus riparius. La mise en interaction de ces organismes au sein d'un mésocosme a également conduit à l'observation de génotoxicité chez le pleurodèle en présence de GO.

Benthic ecosystems are important areas both in terms of biodiversity and functioning. They are receiving direct or indirect inputs from the water column or from the watershed and may therefore be accumulating zones for contaminants. Many benthic and epibenthic organisms may be exposed to these substances, with as consequences, disruption of ecological traits and functions at the ecosystem level such as changes in benthic community structure and ecosystem functioning. However, knowledge about the ecotoxicological effects of accumulated contaminants at the benthic community level is scarce. Accordingly, the present study aimed at assessing the functional impact of chronic exposure to environmental concentrations of metals on natural sediment communities. We evaluate the usefulness of assessing/studying feeding activity and organic matter breakdown as endpoints, using two kinds of artificial organic matter substrates.

International audience

International audience

EABIOMEAGROSUP; De par leur structure tridimensionnelle, leur large gamme de porosité, la diversité de leurs caractéristiques physicochimiques et des conditions microclimatiques, les sols abritent un nombre considérable, parfois inestimable d'organismes. Au sein des agroécosystèmes, les enjeux sont de comprendre les relations entre la plante cultivée et son environnement biophysique incluant les interactions biologiques et les effets de la biodiversité des organismes des sols. L’impact de la faune du sol sur la production primaire peut être vu au travers de leur effet sur les fonctions de (i) recyclage des nutriments, (ii) entretien de la stabilité/structure du sol, (iii) contrôle des bioagresseurs et (iv) support de biodiversité. Ces fonctions écosystémiques sont respectivement associées du point de vue des plantes à (i) leur nutrition, (ii) le milieu physique dans lequel les plantes se développent, (iii) leur santé et (iv) les interactions entre plantes. L’effet de la faune du sol sur chaque fonction peut être expliqué par de nombreux processus et mécanismes qui impliquent l’ensemble des organismes des sols. Ces différents processus sont détaillés dans ce chapitre.

Bacillus thuringiensis var. israelensis (Bti) is commonly used for selective control of larval populations of mosquitoes in coastal wetlands. A two year-study was implemented to investigate whether repeated treatments with Bti applied either as a liquid (VectoBac (R) 12AS) or a water-dispersible granule (VectoBac (R) WG) formulation may affect the abundance and diversity of non-target aquatic invertebrates in saltmarsh pools. Taxonomic composition of the invertebrate communities was typical of brackishwater intermittent ecosystems, with a dominance of annelids, crustaceans and nematocerans. Conditions were contrasted between the two years of the survey, both in terms of annual cumulative rainfall and rainfall distribution throughout the year. As a consequence, the hydroperiod and some other environmental characteristics associated with pool drying played a major role in the dynamics of the invertebrate community. In summer 2006, pool drying reduced the abundance of the polychaete worm Nereis diversicolor, of the amphipod crustacean Corophium volutator and of chironomid larvae. These taxa were able to recolonize rapidly the pools after flooding in September 2006. In 2007, rainfall was more regularly distributed across the year, and the pools did not get dry. Hydrozoans, Chironomini and Orthocladiinae larvae, and oligochaetes were more abundant in treated than in control pools, especially in VectoBac (R) WG-treated pools. No adverse effects of the treatments were shown on the abundance of N. diversicolor, C. volutator and midge larvae, suggesting that the availability of these food sources for birds was not negatively affected by Bti applications. It is concluded that, as currently performed in Western France coastal wetlands, land-based treatments of saltmarsh pools for larval mosquito control with Bti, used either as VectoBac (R) 12AS or VectoBac (R) WG, did not adversely impact non-target aquatic invertebrate communities. (C) 2011 Elsevier Inc. All rights reserved.

The dam reservoirs of the Upper Rhone were drained every three years until 2003, and the water level of the Villebois reservoir was lowered by 1.5 m. This resulted in considerable drying of its littoral habitats and the disappearance of the abundant macro-invertebrates that live in them. This study investigates the response to this drying disturbance of bivalve populations and especially of the life history traits of the two potamic species, Pisidium moitessierianum and Pisidium supinum. The low density of these bivalves observed during the months following the drying of May 2003 until spring 2004 shows that the contribution of drift in population recovery was very limited during this period. Due to the faster turnover of its cohorts and a higher increase in litter size in 2004, P. moitessierianum once again dominated bivalve communities from 2005 onwards. In the Villebois reservoir recovery of bivalve communities in terms of structure and density was total three years after the drying of 2003. Observations suggest an increase in litter size and continuous recruitment: the reproductive strategy adopted by these bivalves represent response to the fall in numbers on the one hand, and to considerable magnitudes of temperature and flow rates on the other hand, enabling the rapid adjustment of populations to drying disturbance and variations in environmental conditions. Taking into account the response of bivalve populations to this event, its effects are comparable to those of a supra-seasonal drought (Lake, 2003, Freshw. Biol., 48, 11611172).

A multipolluted soil sampled from a former coking plant in Lorraine (France) was evaluated for its genotoxic effects on coelomocytes of the Eisenia fetida earthworm using the comet assay. The biological efficiency of thermal desorption of the contaminated soil was also investigated. The untreated polluted soil was shown to be genotoxic to earthworms. Although thermal desorption reduced the concentration of PAHs by 94% ([summation operator]16 PAHs=1846 and 101 mg/kg before and after thermal desorption, respectively), the treatment did not eliminate the genotoxicity of soil pollutants to earthworms but increased it. The concentration of non-volatile metals did not change after thermal desorption. Among metals found in the treated soil, cadmium, chromium and nickel could explain the genotoxicity of the contaminated soil after thermal desorption. The treatment could increase the bioavailability and genotoxicity of heavy metals, through a modification of the soil's organic matter, the speciation of heavy metals and their binding to organic matter. This study underlines the importance of measuring biological effects, in order to evaluate the risk associated with formerly contaminated soils and the efficiency of remediation.

Les biomarqueurs sont des outils mis en oeuvre pour établir un diagnostic de risque environnemental. Leurs usages et leur intérêt, notamment dans la détermination du risque de pollution, sont devenus incontournables surtout depuis que la directive cadre européenne sur l'eau a imposé la surveillance de l'état écologique des cours d'eau.Cependant, le manque de connaissances sur la biochimie, la physiologie et le comportement des organismes aquatiques sentinelles utilisés limitent fortement l'utilisation optimale de ces outils. Quelles sont les connaissances disponibles sur les biomarqueurs ? Comment les utiliser et quelles sont les limites actuelles ? Autant de questions auxquelles cet article tente de répondre.

Laboratory microcosms were used to determine how leaf degradation processes (C–CO2 release and leaf mass loss) are affected by the diversity of soil macro-invertebrate assemblages (comprising earthworms, woodlice and millipedes). The relationships were tested using different measures of diversity (number of species and trait dissimilarities). Net diversity effects and transgressive overyielding were calculated to disentangle the relative impacts of negative, neutral and positive species interactions on the relationships observed. Minimum trait dissimilarities were found to be correlated with leaf mass loss and, to a lesser extent, with C–CO2 release. This suggests that process rates increase as trait similarity in species assemblage decreases. Conversely, increasing the number of species resulted in the saturation of process rates after 1–2 species had been added to a microcosm. The process rates observed could mainly be explained by positive species interactions (40–50% of microcosms being process-dependent), followed by neutral interactions (20–40%) and selection effects or negative interactions (less than 20%). These results thus suggest that the effects of a soil macro-invertebrate assemblage on soil processes are more likely to be driven by complementarity or facilitation than by competition., Es wurden Labormikrokosmen benutzt, um zu bestimmen, wie die Blattzersetzungsprozesse (C CO2-Freisetzung und Blattmassenverlust) durch die Diversität der Boden-Makroinvertebraten-Gemeinschaften (zusammengesetzt aus Würmern, Asseln und Tausendfüsslern) beeinflusst werden. Die Beziehungen wurden untersucht, indem verschiedene Maße der Diversität (Artenzahl und Dissimilarität der Eigenschaften) benutzt wurden. Die Netto-Diversitätseffekte und der transitive Überfluss wurden berechnet, um die relativen Auswirkungen der negativen, neutralen und positiven Interaktionen zwischen den Arten auf die beobachteten Beziehungen zu trennen. Die Dissimilarität sowohl in den Eigenschaften der Faezes als auch in den morphologischen Eigenschaften korrelierten mit dem Verlust der Blattmasse und in geringerem Maße mit der C CO2-Freisetzung und lässt vermuten, dass eine begrenzte Ähnlichkeit zwischen den koexistierenden Arten zu einer höheren Rate des Prozesses führt. Eine Erhöhung der Artenzahl resultierte in einer Sättigung des Prozesses wenn 1–2 Arten zu den Mikrokosmen hinzugefügt wurden. Die beobachteten Raten der Prozesse konnten vor allem mit positiven Interaktionen zwischen den Arten erklärt werden (40% bis 50% der Mikrokosmen waren prozessabhängig), gefolgt von neutralen Interaktionen (20% bis 40%) und Selektionseffekten bzw. negativen Interaktionen (weniger als 20%). Die Ergebnisse lassen daher vermuten, dass die Auswirkungen einer Boden-Makroinvertebraten-Gesellschaft mit größerer Wahrscheinlichkeit durch Komplementarität oder Begünstigung als durch Konkurrenz gesteuert werden.

Immunity in invertebrates was for long analyzed in terms of the overall response; this resulted in misunderstandings concerning specificity and memory. Recent reports of maternal transmission of immunity, and the discovery of the high diversity of receptors-effectors, have required the status of innate immunity to be reconsidered. There are few examples of obvious specificity towards some pathogens, but this cannot be generalized to all invertebrate species. The existence of memory is even more controversial. Here, we suggest looking for immune memory by quantifying key molecular effectors (i) within single individuals following first and second exposures to a pathogen and (ii) in primed mother and her offspring.

/ Ce poster a pour objectif de présenter de manière vulgarisée le travail des équipes EMHA et Ecotox d'Irstea Lyon et notamment leur utilisation des communautés microbiennes et des invertébrés pour évaluer l'impact des perturbations dans les rivières.

International audience; In naturally disturbed systems, harsh environmental conditions act as filters on the regional species pool, restricting the number of taxa able to form a local community to those with traits promoting resistance or resilience. Thus, communities in highly disturbed ecosystems may be less sensitive to a given disturbance than those in less disturbed ecosystems. We explored this idea by examining the response of aquatic invertebrate communities to flow intermittence in gravel-bed, braided rivers (BRs). Flow intermittence is considered a major driver of communities in rivers, but its influence on communities in BRs, which are recognized as naturally highly disturbed environments, is relatively unexplored. We used a multisite Before-After–Control- Impact (BACI) design to quantify the effects of drying events of different durations (moderate: 2–3 wk, severe:1–3 mo) on invertebrate communities in 8 BRs in southeastern France. As predicted, no effects of flow intermittence were detected 1 to 4 mo after flow resumption on taxonomic richness, composition, or functional diversity of communities facing moderate drying events. Communities subjected to severe drying events were similar to those in perennial reaches as few as 19 d after flow resumption. Moreover, communities showed functional redundancy and no loss of functional diversity after drying events. These results differ from those of studies in other river systems, where persistent effects of flow intermittence on communities generally have been found, and highlight the need for cross-system comparisons that explore the effects of drying on communities. Identifying the processes (e.g., niche selection, cotolerance) and habitat features (e.g., hyporheic zone refugia) that promote community resilience in BRs will advance our understanding of how anthropogenic stressors and climate change may affect communities in freshwater ecosystems.

Description du sujet. L’article traite de la macrofaune du sol, composante clé du fonctionnement biologique du sol.Objectifs. Cette étude, réalisée en 2015, a eu pour objectif de tester l’effet de pratiques culturales et de systèmes de culture sur la macrofaune du sol dans une zone d’agriculture-élevage des Hautes-Terres de Madagascar. Cinq systèmes de culture ont été étudiés : cultures annuelles labourées annuellement avec apport de fumier modéré (LAMF) ou élevé (LAEF), cultures fourragères pérennes sans labour et avec apport de fumier élevé (CFEF), cultures annuelles en agriculture de conservation sans labour et apport de fumier modéré (ACMF) et pâturages permanents, non labourés et sans apport de fumier (PP0F).Méthode. Pour chaque système de culture, 12 parcelles d’expérimentation ou d’exploitation agricole ont fait l’objet d’un échantillonnage de la macrofaune du sol avec cinq monolithes de sol par parcelle, sur 30 cm de profondeur. Résultats. Cinquante-deux espèces d’invertébrés, classées en 15 ordres taxonomiques et 6 groupes fonctionnels, ont été identifiées. Pour les cultures annuelles sans labour, l’absence de travail du sol a favorisé la diversité taxonomique et la densité de la macrofaune, n’a pas réduit la densité des vers blancs (larves de Coléoptères Scarabeoideae) rhizophages mais a entrainé une diminution des densités de vers de terre par rapport au mode de culture fourragère. En systèmes labourés, l’intensité d’application du fumier n’a eu d’effet ni sur les vers blancs ni sur les vers de terre.Conclusions. Cette étude sur la macrofaune du sol dans cette région de Madagascar a permis de mieux percevoir les pratiques et les systèmes les plus favorables aux invertébrés utiles (comme les vers de terre) et plus défavorables aux invertébrés nuisibles (comme les vers blancs). Ceci permettra d’orienter les paysans dans la gestion de leurs terres., Crop management and soil macrofauna diversity in the Highlands of MadagascarDescription of the subject. This article deals with soil macrofauna as a key component of soil biological functioning.Objectives. This original study, performed in 2015, aimed to compare the effect of contrasted land uses and cultural practices on soil macrofauna in a crop-livestock area in the Madagascar Highlands. Five cropping systems were investigated: annual crops under tillage with low (LAMF) and high (LAEF) manure inputs, permanent tilled forage crops with high manure inputs (CFEF), crops under conservation agriculture without tillage or permanent mulch cover and with medium manure inputs (ACMF), and permanent pastures without tillage and without manure (PP0F).Method. In each of these five cropping systems, soil macrofauna was sampled in 12 plots from experimental trials and smallholder farms at the end of the rainy season. In each plot, soil macrofauna was hand-sorted from five soil monoliths at a 0-30 cm depth.Results. Fifty-two species were identified and organized into 15 orders and six functional groups. In the annual cropping systems (ACMF), the absence of tillage and the presence of a permanent soil cover increased soil macrofauna diversity and density without reducing harmful white grubs (Scarabeoid beetle larvae), while earthworm density was reduced in comparison with the CFEF system. In conventional tillage cropping systems, manure input intensity (LAMF versus LAEF) had no specific effects on white grubs or earthworms.Conclusions. This study on soil macrofauna in the Highlands of Madagascar helped to establish which agricultural practices and farming systems are favourable to beneficial soil invertebrates such as earthworms, and unfavourable to harmful insects such as white grubs. This will help farmers to achieve a more sustainable crop management.

List of contributors Foreword Introduction Serge Morand, Boris Krasnov and Tim Littlewood Part I. Evolutionary Ecology of Parasite Diversity: 1. Quantifying parasite diversity Robert Poulin 2. Relationships between parasite diversity and host diversity Boris Krasnov and Robert Poulin 3. Patterns of diversity and distribution of aquatic invertebrates and their parasites Tommy L. F. Leung, Camilo Mora and Klaus Rohde 4. Under the changing climate: how shifting geographic distributions and sexual selection shape parasite diversification Lajos Rozsa, Piotr Tryjanowski and Zoltan Vas 5. Impacts of parasite diversity on wild vertebrates: limited knowledge but important perspectives Frederic Bordes and Serge Morand Part II. The Evolutionary History of Parasite Diversity: 6. Revealing parasite diversity using brute force molecular techniques and gently persuasive microscopy Aurelie Chambouvet, Thomas A. Richards, David Bass and Sigrid Neuhauser 7. Evolution of simian retroviruses Ahidjo Ayouba and Martine Peeters 8. The diversity and phylogeny of Rickettsia Lucy A. Weinert 9. Advances in the classification of Acanthocephalans: evolutionary history and evolution of the parasitism Martin Garcia-Varela and Gerardo Perez-Ponce de Leon 10. The study of primate evolution from a lousy perspective David L. Reed, Julie M. Allen, Melissa A. Toups, Bret Boyd and Marina Ascunce 11. Host correlates of diversification in avian lice Lajos Rozsa and Zoltan Vas 12. Evolutionary history of Siphonaptera: fossils, origins, vectors Katharina Dittmar, Qiyun Zhu, Michael W. Hastriter and Michael F. Whiting 13. Bat fly evolution from the Eocene to the present (Hippoboscoidea, Streblidae and Nycteribiidae) Katharina Dittmar, Solon F. Morse, Carl W. Dick and Bruce D. Patterson 14. The evolution of parasitism and host associations in mites Ashley Dowling 15. Nematode life-traits diversity in the light of their phylogenetic diversification Serge Morand, Steve Nadler and Arne Skorping 16. Phylogenetic patterns of diversity in the cestodes and trematodes Timothy J. Littlewood, Rodney A. Bray and Andrea Waeschenbach 17. Patterns of diversification in the parasites of Caribbean Anolis lizards Bryan G. Falk and Susan L. Perkins Part III. Combining Ecology and Phylogenetics: 18. Comparative analysis - recent developments and uses with parasites Yves Desdevises, Serge Morand, Boris R. Krasnov and Julien Claude 19. Phylogenetic signals in ecological properties of parasites Boris R. Krasnov, Serge Morand and Robert Poulin 20. Parasite species coexistence and the evolution of the parasite niche Andrea Simkova and Serge Morand 21. A community perspective on the evolution of virulence Hadas Hawlena and Frida Ben-Ami 22. Host-specificity and species jumps in fish-parasite systems Maarten P. M. Vanhove and Tine Huyse 23. When is cophylogeny evidence of coevolution? Timothee Poisot 24. Bringing together phylogenies and behaviour in host-parasite interactions Tania Jenkins and Philippe Christe 25. The evolutionary epidemiology of the Hepatitis C virus Peter V. Markov, Rebecca R. Gray, James Iles and Oliver G. Pybus Conclusion and perspectives Armand Kuris Index.

International audience

Soil science integrates specific contributions from physics, chemistry, biology, and the human sciences. During the last 2 decades, these approaches, which had primarily developed separately and at different speeds, have been progressively integrated. Ecology has contributed a significant number of integrative concepts and questions, some, such as nutrient cycling and energy budgets, that are rather old, and others, such as soil engineering by microinvertebrates, the relationship between biodiversity and soil function, and the impact of landscape fractionation, that are more recent. An important issue common to all disciplines in soil science is that of scales. Ecological studies have shown that similar activities, e.g., the building of solid structures by invertebrates for their sheltering or gut transit of soil for digestion, may affect soil function at different scales, affecting the rates of processes in sometimes opposite directions. The concept of functional domains in soil, derived from soil ecological research, defines a scale at which physical, chemical, and biological processes can be studied efficiently in a true multidisciplinary approach. Functional domains are specific sites in soils defined by a main organic resource (leaf litter or soil organic matter), a major regulator, biotic (i.e., an invertebrate "engineer" or roots) or abiotic (like freezing/ thawing or drying/rewetting alternates), a set of structures created by the regulator (for example fecal pellets, galleries, or cracks), and a community of dependent invertebrates of smaller size microorganisms that live in these structures. Functional domains may be physically identified in soils and specifically studied using the different disciplinary approaches. Specific micromorphologic, isotopic, and other techniques allow us to address issues at this scale adequately... (D'après résumé d'auteur)

The effect of organic enrichment on earthworm activity and soil structure was studied in two French vineyards, by comparing control and test plots. In each vineyard the organic matter quantitatively increased the abundance and biomass of the earthworm community. These increases were associated with a higher level of species diversity and a higher evenness corresponding to the development of endogeic community. These earthworm community changes were associated with an increase in granular bioturbated areas and in macroporosity in the top soil layer. The micromorphological approach incorporated an original process of image analysis which appeared to be an appropriate method for characterizing pore morphology in this study. The pores when characterized by their size and shape could be related to ecological groups and growth stages of earthworms.

Members of the family Iridoviridae are animal viruses that infect only invertebrates and poikilothermic vertebrates. The invertebrate iridoviruses 22 (IIV22) and 25 (IIV25) were originally isolated from a single sample of blackfly larva (Simulium spp., order Diptera) collected from the Ystwyth river near Aberystwyth, Wales. Recently, the genomes of IIV22 (197.7 kbp) and IIV25 (204.8 kbp) were sequenced and reported. Here, we describe the complete genome sequence of IIV22A, a variant that was isolated from the same pool of virions collected from the blackfly larva from which the IIV22 virion genome originated. The IIV22A genome, 196.5 kbp, is smaller than IIV22. Nevertheless, it contains 7 supplementary putative ORFs. Its analysis enables evaluation of the degree of genomic polymorphisms within an IIV isolate. Despite the occurrence of this IIV variant with IIV22 and IIV25 in a single blackfly larva and the features of their DNA polymerase, we found no evidence of lateral genetic transfers between the genomes of these two IIV species.

Vertebrate females transfer antibodies via the placenta, colostrum and milk or via the egg yolk to protect their immunologically immature offspring against pathogens. This evolutionarily important transfer of immunity is poorly documented in invertebrates and basic questions remain regarding the nature and extent of parental protection of offspring. In this study, we show that a lipopolysaccharide binding protein/bactericidal permeability increasing protein family member from the invertebrate Biomphalaria glabrata (BgLBP/BPI1) is massively loaded into the eggs of this freshwater snail. Native and recombinant proteins displayed conserved LPS-binding, antibacterial and membrane permeabilizing activities. A broad screening of various pathogens revealed a previously unknown biocidal activity of the protein against pathogenic water molds (oomycetes), which is conserved in human BPI. RNAi-dependent silencing of LBP/BPI in the parent snails resulted in a significant reduction of reproductive success and extensive death of eggs through oomycete infections. This work provides the first functional evidence that a LBP/BPI is involved in the parental immune protection of invertebrate offspring and reveals a novel and conserved biocidal activity for LBP/BPI family members., Author Summary Vertebrate immune systems not only protect adult organisms against infections but also increase survival of offspring through parental transfer of innate and adaptive immune factors via the placenta, colostrum and milk or via the egg yolk. This maternal transfer of immunity is critical for species survival as embryos and neonates are immunologically immature and unable to fight off infections at early life stages. Parental immune protection is poorly documented in invertebrates and how the estimated 1.3 million of invertebrate species protect their eggs against pathogens remains an intriguing question. Here, we show that a fresh-water snail, Biomphalaria glabrata massively loads its eggs with a lipopolysaccharide binding protein/bactericidal permeability increasing protein (LBP/BPI) displaying expected antibacterial activities. Remarkably, this snail LBP/BPI also displayed a strong biocidal activity against water molds (oomycetes). This yet unsuspected activity is conserved in human BPI. Gene expression knock-down resulted in the reduction of snail reproductive success and massive death of eggs after water mold infections. This work reveals a novel and conserved biocidal activity for LBP/BPI family members and demonstrates that the snail LBP/BPI represents a major fitness-related protein transferred from parents to their clutches and protecting them from widespread and lethal oomycete infections.

An examination of Palaeozoic sections west of Cochabamba, and west of Lake Poopo, in western Bolivia, was conducted during a field expedition in 1991. The Rio Iglesiani valley, west of Cochabamba, surprisingly yielded a Middle Devonian age to all the visited sites, originally supposed to be Ordovician. This result is based on spores, shelly faunas (brachiopods and bivalves), and trilobites. The Copacabana de Andamarca section, west of Lake Poopo, is also dated as Middle Devonian on account of its rather rich fauna (bryozoans, corals, brachiopods, conulariids, hyolithids, tentaculitids, ostracodes, trilobites, crinoids, vertebrates). Both localities correlate to the Icla and/or Huamampampa Formation of the Tarabuco area and Subandean belt, and to the Belen and/or Sica Sica Formation of the northern Altiplano.

In animals, the population genomic literature is dominated by two taxa, namely mammals and drosophilids, in which fully sequenced, well-annotated genomes have been available for years. Data from other metazoan phyla are scarce, probably because the vast majority of living species still lack a closely related reference genome. Here we achieve de novo, reference-free population genomic analysis from wild samples in five non-model animal species, based on next-generation sequencing transcriptome data. We introduce a pipe-line for cDNA assembly, read mapping, SNP/genotype calling, and data cleaning, with specific focus on the issue of hidden paralogy detection. In two species for which a reference genome is available, similar results were obtained whether the reference was used or not, demonstrating the robustness of our de novo inferences. The population genomic profile of a hare, a turtle, an oyster, a tunicate, and a termite were found to be intermediate between those of human and Drosophila, indicating that the discordant genomic diversity patterns that have been reported between these two species do not reflect a generalized vertebrate versus invertebrate gap. The genomic average diversity was generally higher in invertebrates than in vertebrates (with the notable exception of termite), in agreement with the notion that population size tends to be larger in the former than in the latter. The non-synonymous to synonymous ratio, however, did not differ significantly between vertebrates and invertebrates, even though it was negatively correlated with genetic diversity within each of the two groups. This study opens promising perspective regarding genome-wide population analyses of non-model organisms and the influence of population size on non-synonymous versus synonymous diversity., Author Summary The analysis of genomic variation between individuals of a given species has so far been restricted to a small number of model organisms, such as human and fruitfly, for which a fully sequenced, well-annotated reference genome was available. Here we show that, thanks to next-generation high-throughput sequencing technologies and appropriate genotype-calling methods, de novo population genomic analysis is possible in absence of a reference genome. We characterize the genomic level of neutral and selected polymorphism in five non-model animal species, two vertebrates and three invertebrates, paying particular attention to the treatment of multi-copy genes. The analyses demonstrate the influence of population size on genetic diversity in animals, the two vertebrates (hare, turtle) and the social insect (termite) being less polymorphic than the two marine invertebrates (oyster, tunicate) in our sample. Interestingly, genomic indicators of the efficiency of natural selection, both purifying and adaptive, did not vary in a simple, predictable way across organisms. These results prove the value of a diversified sampling of species when it comes to understand the determinants of genome evolutionary dynamics.

International audience; Phenol is a major pollutant in aquatic ecosystems due to its chemical stability, water solubility and environmental mobility. To date, little is known about the molecular modifications of invertebrates under phenol stress. In the present study, we used Solexa sequencing technology to investigate the transcriptome and differentially expressed genes (DEGs) of midges (Chironomus kiinensis) in response to phenol stress. A total of 51,518,972 and 51,150,832 clean reads in the phenol-treated and control libraries, respectively, were obtained and assembled into 51,014 non-redundant (Nr) consensus sequences. A total of 6,032 unigenes were classified by Gene Ontology (GO), and 18,366 unigenes were categorized into 238 Kyoto Encyclopedia of Genes and Genomes (KEGG) categories. These genes included representatives from almost all functional categories. A total of 10,724 differentially expressed genes (P value

International audience; A long-term programme of hydrological and ecological restoration has been conducted on the French Rhone River since 1998. Its main components are i the increase of the minimum flow in the river sections bypassed by an hydro-power plant, ii the direct reconnection of cut-off channels to the river, iii the dredging of isolated pools within the channels. The presentation highlights a selection of key findings from the pre- and post-restoration monitoring of fish and macroinvertebrate assemblages in the River and its floodplain, carried out in four different sectors since 1995.

International audience; This article documents the addition of 299 microsatellite marker loci and nine pairs of single-nucleotide polymorphism (SNP) EPIC primers to the Molecular Ecology Resources (MER) Database. Loci were developed for the following species: Alosa pseudoharengus, Alosa aestivalis, Aphis spiraecola, Argopecten purpuratus, Coreoleuciscus splendidus, Garra gotyla, Hippodamia convergens, Linnaea borealis,Menippe mercenaria,Menippe adina, Parus major, Pinus densiflora, Portunus trituberculatus, Procontarinia mangiferae, Rhynchophorus ferrugineus, Schizothorax richardsonii, Scophthalmus rhombus, Tetraponera aethiops, Thaumetopoea pityocampa, Tuta absoluta and Ugni molinae. These loci were cross-tested on the following species: Barilius bendelisis, Chiromantes haematocheir, Eriocheir sinensis, Eucalyptus camaldulensis, Eucalyptus cladocalix, Eucalyptus globulus, Garra litaninsis vishwanath, Garra para lissorhynchus, Guindilla trinervis, Hemigrapsus sanguineus, Luma chequen. Guayaba, Myrceugenia colchagu¨ensis, Myrceugenia correifolia, Myrceugenia exsucca, Parasesarma plicatum, Parus major, Portunus pelagicus, Psidium guayaba, Schizothorax richardsonii, Scophthalmus maximus, Tetraponera latifrons, Thaumetopoea bonjeani, Thaumetopoea ispartensis, Thaumetopoea libanotica, Thaumetopoea pinivora, Thaumetopoea pityocampa ena clade, Thaumetopoea solitaria, Thaumetopoea wilkinsoni and Tor putitora. This article also documents the addition of nine EPIC primer pairs for Euphaea decorata, Euphaea formosa, Euphaea ornata and Euphaea yayeyamana.

From 2 investigations in may and September on 40 sites of the River Sensee, 6 indices have been applied on Diatoms and Invertebrates . Biologic , physical and chemical data have been treated by a P.C. A . Unlike the invertebrates, Diatomic indexes seem to be weakly correlated with the different physicial and chemical parameters used for the assessment of the water quality. It is both linked to the instantaneous feature of chemical analysis and the different integrating power of the two kinds of bioindicators. Diatom indices traduce the eutrophication and give more expressive results than macroinvertebrates indices. Use of Diatom and Diatom indices in heterogeneous rivers is really a problem linked to the gap in standardized methods., Deux campagnes de prélèvements hydrobiologiques ont été réalisées en mai et en septembre sur le bassin versant de la rivière Sensée. Sur l’ensemble des 40 stations ont été calculés six indices diatomiques et deux indices invertébrés. Les données biologiques et physico-chimiques ont été traitées en analyse en composantes principales. Contrairement aux indices invertébrés, les indices diatomiques apparaissent peu corrélés aux différents paramètres chimiques indicateurs de la qualité de l’eau. Ceci est du au caractère instantané des analyses chimiques mais aussi à la différence de pouvoir intégrateur entre ces deux types de bioindicateurs. Les indices diatomiques intègrent les phénomènes d’ eutrophisation et donnent des résultats beaucoup plus nuancés que les indices invertébrés. L’ utilisation des diatomées et des indices diatomiques dans des milieux très hétérogènes n’est cependant pas sans poser de problèmes en raison du manque de standardisation des méthodes., Prygiel Jean. Comparaison de six indices diatomiques et deux indices invertébrés pour l’estimation de la qualité de l’eau de la rivière Sensée (France). In: Ecologia mediterranea, tome 20 n°1-2, 1994. pp. 121-133.

Background Flexible genomes facilitate bacterial evolution and are classically organized into polymorphic strain-specific segments called regions of genomic plasticity (RGPs). Using a new web tool, RGPFinder, we investigated plasticity units in bacterial genomes, by exhaustive description of the RGPs in two Photorhabdus and two Xenorhabdus strains, belonging to the Enterobacteriaceae and interacting with invertebrates (insects and nematodes). Results RGPs account for about 60% of the genome in each of the four genomes studied. We classified RGPs into genomic islands (GIs), prophages and two new classes of RGP without the features of classical mobile genetic elements (MGEs) but harboring genes encoding enzymes catalyzing DNA recombination (RGPmob), or with no remarkable feature (RGPnone). These new classes accounted for most of the RGPs and are probably hypervariable regions, ancient MGEs with degraded mobilization machinery or non canonical MGEs for which the mobility mechanism has yet to be described. We provide evidence that not only the GIs and the prophages, but also RGPmob and RGPnone, have a mosaic structure consisting of modules. A module is a block of genes, 0.5 to 60 kb in length, displaying a conserved genomic organization among the different Enterobacteriaceae. Modules are functional units involved in host/environment interactions (22-31%), metabolism (22-27%), intracellular or intercellular DNA mobility (13-30%), drug resistance (4-5%) and antibiotic synthesis (3-6%). Finally, in silico comparisons and PCR multiplex analysis indicated that these modules served as plasticity units within the bacterial genome during genome speciation and as deletion units in clonal variants of Photorhabdus. Conclusions This led us to consider the modules, rather than the entire RGP, as the true unit of plasticity in bacterial genomes, during both short-term and long-term genome evolution.