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Phylogenetically closely related plant species often share similar trait states (phylogenetic signal), but local assembly may favor dissimilar relatives and thereby decouple the diversity of a trait from the diversity of phylogenetic lineages. Associated fauna might either benefit from plant trait diversity, because it provides them complementary resources, or suffer from it due to dilution of preferred resources. We hence hypothesize that decoupling of trait and phylogenetic diversity weakens the relationship between the plant-trait diversity and the abundance and diversity of associated fauna. Studying permanent meadows, we tested for combined effects of plant phylogenetic diversity and diversity of two functional traits (specific leaf area, leaf dry matter content) on major groups of soil fauna (earthworms, mites, springtails, nematodes). We found that only in phylogenetically uniform plant communities, was uniformity in the functional traits associated with (i) high abundance in springtails, and (ii) high abundance of the sub-group that feeds more directly on plant material (in springtails and mites) or those that are more prone to disturbance (in nematodes), and (iii) high diversity in all three groups tested (springtails, earthworms, nematodes). Our results suggest that soil fauna profits from the resource concentration in local plant communities that are uniform in both functional traits and phylogenetic lineages. Soil fauna would hence benefit from co-occurrence of closely related plants that have conserved the same trait values, rather than of distantly related plants that have converged in traits. This might result in faster decomposition and a positive feedback between trait conservatism and ecosystem functioning.

International audience; Background and aims Soil aggregate stability depends on plant community properties, such as functional group composition, diversity and biomass production. However, little is known about the relative importance of these drivers and the role of soil organisms in mediating plant community effects. Methods We studied soil aggregate stability in an experimental grassland plant diversity gradient and considered several explanatory variables to mechanistically explain effects of plant diversity and plant functional group composition. Three soil aggregate stability measures (slaking, mechanical breakdown and microcracking) were considered in path analyses. Results Soil aggregate stability increased significantly from monocultures to plant species mixtures and in the presence of grasses, while it decreased in the presence of legumes, though effects differed somewhat between soil aggregate stability measures. Using path analysis plant community effects could be explained by variations in root biomass, soil microbial biomass, soil organic carbon concentrations (all positive relationships), and earthworm biomass (negative relationship with mechanical breakdown). Conclusions The present study identified important drivers of plant community effects on soil aggregate stability. The effects of root biomass, soil microbial biomass, and soil organic carbon concentrations were largely consistent across plant diversity levels suggesting that the mechanisms identified are of general relevance.

Resume Les donnees scientifiques recentes permettent de comprendre la grande variabilite des methodes de dosage des anticorps antiphospholipides (APA). Ces anticorps reagissent avec les complexes β2-glycoproteine I (β2GPI)-phospholipides anioniques (PLP). Dans certains cas, ils reagissent aussi avec la β2GPI insolubilisee. Bien qu'il n'y ait que peu de specificite d'espece, certains APA reagissent preferentiellement avec les complexes de β2GPI humaine et de PLP. Nous avons developpe de nouveaux dosages optimises qui utilisent en coating des PLP anioniques satures par un serum humain exempt d'immunoglobulines comme source de β2GPI, et un serum animal (par exemple chevre) pour eviter les reactions non specifiques, serum qui est egalement utilise pour le diluant. Le calibrateur du dosage doit permettre de definir la zone de reactivite positive et la valeur seuil determinee par rapport a au moins 200 plasmas provenant d'individus normaux (moyenne + 3 ecarts types ou 95 % percentiles) et de pathologies exemptes d'APA.

The life cycle of Dendrobaena veneta was studied to assess the potential of breeding this species for the fish-bait market. Development, growth and reproduction were investigated by rearing worms at 10°, 15°, 20° or 25°C on horse manure or on aerobic paper sludge for 6 months. At 10°C, the maturity was slow with a long period of development (104 d) and a low cocoon production. Productivity at 25°C was better than at 20°C or 15°C. The effect of temperature on cocoon production differed according to the source of food; on paper sludge, cocoons were produced at the same rate at 20 or 25°C while on horse manure cocoon production was better at 25°C than at 20°C. Whatever temperature, cocoon production was significantly greater on paper sludge than on horse manure. On paper sludge, maturation of juveniles was faster and adult worms larger. Adults started to produce cocoons at a younger age and more cocoons were produced worm −1 and d −1 . These results showed that the life cycle of D. veneta may be influenced by the type of food and that horse manure is not the best substrate for breeding this species.

Fire is a recurrent disturbance in heathland landscapes of Brittany. Our study considers relationships between landscape heterogeneity, rate of fire spread and fire frequency. Heterogeneity is defined by the diversity and the fragmentation of landscape units at different scales. This approach of fire processes proves that: (1) perceived landscape heterogeneity is scale dependent; (2) fire speed is correlated with land cover heterogeneity at fine scales, but not at coarse scales; (3) heterogeneity increases with frequent fire, while diversity grows with one fire and reduces with higher fire frequency.

Presence of beta 2 Glycoprotein I (beta 2GPI), in addition to phospholipids, is an absolute requirement for binding APA. This binding is frequently observed with beta 2GPI coated alone, however many APA react only with beta 2GPI complexed to phospholipids, but not with phospholipids alone. We demonstrate that a subgroup of rabbit polyclonal antibodies to human beta 2GPI binds to this protein only when it is coated on a solid surface, but not if it is in solution. In addition, beta 2GPI present in goat serum is strongly fixed by the coated phospholipids and the complexes formed bind as well APA as the rabbit antibodies to beta 2GPI. The diluent used for testing APA, has a strong incidence on APA's reactivity as it can be a source of beta 2GPI. Antibody binding to beta 2GPI, Prothrombin, Protein S, and Annexin V, coated in the presence or in the absence of phospholipids, was tested in 55 patients with the antiphospholipid syndrome. The strongest binding of antibodies was observed in 39 plasma to a mixture of phospholipids and purified human beta 2GPI, however 17 samples also presented a significant reactivity to beta 2GPI alone. Nine plasmas contained antibodies to Prothrombin, 4 to Protein S, 3 to Annexin V, and 1 to Protein C. We conclude that most of the APA are directed to a complex of beta 2GPI and phospholipids although in some patients antibodies to beta 2GPI alone or to other phospholipid binding proteins are present.

International audience; To understand how earthworms could improve soil porosity in no-tillage organic farming systems, the aim of our study was to compare the effect of different tillage systems on earthworm populations, from conventional (traditional mouldboard ploughing, MP and shallow mouldboard ploughing, SMP) to conservation tillage (reduced tillage, RT, direct drilling or very superficial tillage, NT) in three organic arable systems in France (sites A–C). In a second stage, the effect of earthworm activity on soil porosity under the four tillage systems was assessed at sites A and B. Earthworm abundance, biomass and diversity were measured over a 2–3-year period at the 3 sites. During the same period, soil structure (soil profile description and soil bulk density) and open worm burrows in the soil were assessed at sites A and B. After 3 years of experiments, it was found that at 2 sites earthworm abundance and biomass were higher in NT than with ploughing or reduced tillage. The increase of earthworms in NT is mainly due to anecic species increase. Earthworm abundance and biomass tend to decrease regardless of the tillage techniques employed at sites with a ley, and conversely, tend to increase in NT and RT at sites initially ploughed. In the short term, the increase of anecic species in NT has no effect on soil porosity evolution: NT soils were more compacted than those which were ploughed. A long-term experiment is required to assess the effect of biological activity on the physical components of soil in organic farming.

In 1995, the ADEME launched a research program called “Waste Ecocompatibility” in order to define a reliable methodology for measuring the impact of waste in storage or reuse scenarios. The French concept of “Ecocompatibility” is defined as the situation where the pollutant flux from waste disposed of or used in specified conditions is compatible with the environmental acceptance of the receiving environments. The chief feature of this definition is to integrate the evaluation of the three following terms: pollutants emission from the waste, transport of the pollutants from the waste to the receptor cells and the environmental acceptance of the receiving environments. The “Waste Ecocompatibility” program consisted of a literature survey and an experimental part. The literature study aimed to determine factors and waste characteristics to be considered for a reliable ecocompatility assessment, to provide an overview of the available tools for measuring those factors and characteristics and to propose a first approach of the methodology. In the framework of the experimental program, this approach was then applied to three theoretical scenarios to validate the laboratory tools (comparative study of laboratory and field results) and to calibrate the global methodology. This paper deals with the results of the experimental program concerning the impact study on receiving environments: impact on plants and microorganisms living in soil, impacts on soil fauna and aquatic fauna. In other papers we intend to present the operational methodology for the assessment of waste ecocompatibility. It includes bio-assays at laboratory scale (microcosms), pilot scale (mesocosms) and in situ experiments (experimental prairie). To limit the use of in situ experiments other research works are necessary to validate bio-assays at laboratory or pilot scale.

Phospholipid dependent antibodies are usually measured with assays for antiphospholipid/anticardiolipin antibodies (aPLA) or for lupus anticoagulant (LA) activity. Most of them are targeted to complexes of beta 2-glycoprotein I (beta 2-GPI) and anionic phospholipids (PLP) or to prothrombin for some LA. New understandings allow a better standardisation and optimisation of assays' reactivity. Antigenic targets of phospholipid dependent antibodies were studied on plasmas from 38 patients with the antiphospholipid syndrome (APS) and presenting aPLA and/or LA. Using human beta 2-GPI-PLP complexes as solid phase antigen offers the highest sensitivity for measuring aPLA. Many aPLA, but not all, also react with beta 2-GPI coated on solid phase, however there is no evidence until now that this latter reactivity shows a closest association with the clinical context. Most of the patients with LA present an immunological reactivity to beta 2-GPI alone or to prothrombin, when these proteins are coated on solid phase. In two cases there was a reactivity to only beta 2-GPI-PLP complexes. For the various immunoassays, using NUNC type I plates offers a good binding capacity for coating antigens. They are then present at enough density on solid phase for insuring an efficient binding of autoantibodies. This is an important factor for assay sensitivity and reproducibility. Interestingly, in 1 case with LA, autoantibodies were reactive with coated beta 2-GPI alone but not with its PLP-complexes. In another case reactivity to beta 2-GPI was much higher than that to beta 2-GPI-PLP.