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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.

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.

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.

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.

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.

Accepte le 19 novembre 2009 T Western Amazonian basin has long been recognized as supporting one of the highest levels of biological diversity in the world. Insects are particularly abundant and species rich in this region, yet the task of describing new species, discovering their range, understanding the factors that govern their distribution and the degree of alteration in their community structure as a result of habitat degradation is still in its early stages. Th e wide diversity of habitats that Ecuador possesses in a small area makes it an ideal location for biodiversity and ecological research. Although the diversity of many groups (e.g. plants, birds, and frogs) has been the focus of numerous publications data on the entomological fauna in Ecuador are scarce, mostly limited to the response of insect diversity to altitudinal gradients. During the past decades, the Ecuadorian research in Entomology has been dominated by taxonomic studies. Face to the acute environmental awareness and called attention to the pressing problem of biodiversity conservation, this taxonomic knowledge has recently been refocused in an ecological perspective. Th e nine contributions to this special issue aim to present some of the major lines of research developed in ecological entomology in Ecuador, mainly at the Museum of Zoology of the Catholic University of Quito (QCAZ), Invertebrate Section. Th e studies concern diff erent ecosystems of Ecuador such as lowland Amazonian rainforests (Carpio et al. 2009, Checa et al. 2009), Montane cloud forest (Donoso & Ramon 2009) and Andean paramos (Moret 2009). Most studies however cover a wide range of biogeographic regions (Badher et al. 2009, Barragan et al. 2009, Donoso et al. 2009, Dangles et al. 2009) including comparisons with other regions from Latin America (Cardenas et al. 2009). Th e coverage of taxa (e.g. Diptera, Isoptera, Hymenoptera, Lepidoptera, Coleoptera), thematic (e.g. taxonomy, biogeography, community ecology, conservation biology) and methodologies (e.g. multi-dimensional analysis, spatial statistics, niche modeling) was designed to highlight the diverse areas on which QCAZ entomologists have focused during the last years, giving a broad view of some of their scientifi c achievements. In spite of their large topical range, the contributions to this special issue are united by a common theme: a focus on how a good knowledge of species taxonomy plays a crucial role in fostering and underpinning ecological research in the fi eld of entomology. Th is is particularly important in tropical countries like Ecuador where the task of entomologists seems to have a time limit with a clock ticking faster and faster as human disturbance continues to increase. I hope that this special issue will not only provide a fresh view of entomological research performed in Ecuador but also foster interest from entomologists worldwide to come and perform research in this country which shelters one of the most species-rich but also most endangered insect fauna on Earth. Acknowledgements. I am grateful to Brigitte Frerot, Pierre Rasmont, and Yves Carton for their enthusiasm in this special issue project and their support for making it a reality. I also thank all the members of the QCAZ Museum, Invertebrates Section for their dedicated contribution to this issue. Special thanks to Raphael Cardenas, for his help in the coordination of the issue. Financial supports from the Pontifi cia Universidad Catolica del Ecuador (Donacion de Impuesto a la Renta), the IRD (UR-072) and the University of Delaware (Department of Entomology & Wildlife Ecology) for the publication of this special issue are greatly acknowledged.

This paper synthesises information on the food requirements of soil macroinvertebrates and some of their effects on soil organic matter dynamics. Some clues to techniques that would optimise their activities through organic matter management are suggested. Soil macroinvertebrates can consume almost any kind of organic residues in mutualistic association with soil microflora. Significant amounts estimated at several T per ha of predominantly easily assimilable C are used yearly in natural ecosystems as energy to sustain these activities. Sources of C used are highly variable depending on the feeding regime. The largest part of the energy assimilated (e.g., 50% by the tropical earthworm Millsonia anomala) is actually spent in burrowing and soil transport and mixing. Bioturbation often affects several thousand tons of soil per hectare per year and several tenth of m3 of voids are created in soil. A great diversity of biogenic structures accumulate and their nature and persistance over time largely controls hydraulic soil properties. The OM integrated into the compact biogenic structures (termite mounds, earthworm globular casts) is often protected from further decomposition. Most management practices have negative effects on the diversity and abundance of macroinvertebrate communities. Structures inherited from faunal activities may persist for some weeks to years and the relationship between their disappearance and soil degradation is rarely acknowledged. When SOM supply is maintained but diversity is not, the accumulation in excess of structures of one single category may have destructive effects on soil. It is therefore essential to design practices that provide the adequate organic sources to sustain the activity and diversity of invertebrates. Special attention should also be paid to the spatial array of plots and rotations in time.

International audience; BACKGROUND: New, practical models of central nervous system regeneration are required and should provide molecular tools and resources. We focus here on the tunicate Ciona intestinalis, which has the capacity to regenerate nerves and a complete adult central nervous system, a capacity unusual in the chordate phylum. We investigated the timing and sequence of events during nervous system regeneration in this organism. METHODOLOGY/PRINCIPAL FINDINGS: We developed techniques for reproducible ablations and for imaging live cellular events in tissue explants. Based on live observations of more than 100 regenerating animals, we subdivided the regeneration process into four stages. Regeneration was functional, as shown by the sequential recovery of reflexes that established new criteria for defining regeneration rates. We used transgenic animals and labeled nucleotide analogs to describe in detail the early cellular events at the tip of the regenerating nerves and the first appearance of the new adult ganglion anlage. CONCLUSIONS/SIGNIFICANCE: The rate of regeneration was found to be negatively correlated with adult size. New neural structures were derived from the anterior and posterior nerve endings. A blastemal structure was implicated in the formation of new neural cells. This work demonstrates that Ciona intestinalis is as a useful system for studies on regeneration of the brain, brain-associated organs and nerves.

Les échantillons ont été prélevés de janvier 1982 à janvier 1983 dans les franges à #Panicum grumosum$ et à #Polygonum acuminatum$ des îles Palomera et Choui, qui sont situées sur le Parana à 45 km en aval de sa confluence avec le Paraguay. Durant la période d'étude, des périodes de hautes et de basses eaux ont été observées, y compris une crue exceptionnelle au cours des derniers mois. En période de basses eaux, les invertébrés associés à la végétation suivent une distribution d'abondance log-normale, avec une forte densité et une diversité de 3,81 bits. Les Copépodes, Cladocères, Oligochètes, et Ostracodes forment les groupes les plus abondants. Lors des périodes prolongées de forte crue, l'abondance et la diversité diminuent, et la distribution est du type géométrique. Durant les crues de plus faible durée, la distribution d'abondance relative est semblable à celle des basses eaux. (Résumé d'auteur)

International audience; This study highlights the effects of interaction between microbial, macro- and meiofauna on NO3−-N and DOC reduction in macroporous stream sediment. The tested hypotheses are: the transformation of nutrients and dissolved organic matter (1) is influenced by the presence of invertebrates, (2) is more effective when the diversity of the vertical benthic community increases. These hypotheses were tested using microcosms reproducing a portion of a river bed water-sediment interface that was colonized with different levels of invertebrate biodiversity. Experimental treatments were abiotic sediment (AS); sediment and biofilm (SB); sediment, biofilm and meiofauna (SBM); and sediment, biofilm, meiofauna and macrofauna community assemblage, which corresponds to the total benthic community of a river bed (SBMM). Reduction rates of nitrates (NO3−-N) and dissolved organic carbon (DOC) in the microcosms were measured and considered as a function of the different levels of biodiversity. Nutrient reduction rates were monitored by their decrease from the aqueous phase. Nitrate reduction rates increased significantly with increasing the vertical biodiversity level. After 56 days of biofilm development, NO3−-N reduction rates ranged from 3.76 ± 0.35 in SB treatment to 8.92 ± 0.69 mg N d−1 kg−1sediment Fresh Weight (sed FW) in the treatment with the maximum biodiversity (SBMM). Denitrification rates increased by a factor of 6 in presence of meiofauna and macrofauna compared to that measured in sediment without invertebrates. DOC reduction rates also varied significantly with biodiversity levels but in a lesser extent than nitrate reduction rates (41.89 ± 2.24 mg C d−1 kg−1sed FW with biofilm alone (SB) to 51.00 ± 1.39 mg C d−1 kg−1sed FW with the addition of meiofauna community) (SBM).

International audience; Despite strong investments dedicated to river physical restoration, it is still difficult to assess the ecological effects of restoration operations. This is largely due to the difficulty of organizing long-term scientific surveys that anticipate operations and allow comparisons of their effects over multiple years in multiple sites. It is even more difficult to assess how ecohydraulic models can predict actual biological responses to stream restoration. As other large rivers in Europe, the Rhône River has been regulated for navigation, irrigation and hydroelectricity since the 19th century. A restoration program of the river started officially in 1998. It has involved minimum flow increases in bypassed main channels, the modifications of the connections of several dozens floodplain channels with the main river and the dredging of their sediments. So far, four bypassed mainchannel sections and 26 floodplain channels have been restored. We used the Rhône restoration project as a template for testing the predictive power of several ecohydraulic models. In particular, we developed models to predict how fish and macroinvertebrate communities should respond to the physical restoration of the river. Some of these were based on hydraulic microhabitat models, that predicted how observed microhabitat preference of fish and invertebrate taxa should result in community changes after restoration. Other models were based on observed correlations between community structure and the degree of connectivity of floodplain channels with the main river. Several years after restoration, important community changes were observed in the restored sites and partly matched model predictions. Most reliable predictions corresponded to situations with strong physical contrasts (e.g. minimum discharge rate multiplied by 10, or reconnection between the floodplain and the main channel). Observations also revealed complex population dynamics and the development of invasive taxa that were not predicted by the models. Such results show the potential of ecohydraulic models for guiding management plans and contribute to quantify their uncertainty.