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International audience; Questions Seedling recruitment is a key step in any seed-based ecological restoration project. There is a controversial discussion (a) whether soil preparation is required to reduce competition of pre-existing vegetation, or whether vegetation cover facilitate seedling recruitment, and (b) whether grazing should be excluded in initial stages of grassland restoration to protect seedlings, because grazing exclusion may also favour competitive ruderal species. We set up a combined soil preparation and grazing experiment to evaluate the effect of both factors on seedling recruitment of seeds transferred from a species-rich donor site.Location Upper Durance valley, Hautes-Alpes, France.Methods The experiment was set up using a full factorial split-plot design with five replicate sites. The treatments included soil preparation (harrowed or not) and grazing (excluded or not). Seeds were transferred using plant material brushed in a non-degraded reference grassland. The individuals of all occurring species were counted on the restoration sites, and the survival and reproduction of two focal species, Bromopsis erecta and Rhinanthus alectorolophus, were recorded for three months.Results Soil preparation by harrowing reduced the density of spontaneously emerging species and increased the seedling density of species transferred from the donor site. Grazing had only a weak negative effect on the recruitment of transferred species. The main effect of both treatments on seedling survival was not significant, but a significant interaction indicated that the grazing effect depended on soil preparation, with a negative effect of grazing only in non-harrowed plots.Conclusions The reduction of competition by soil preparation before seed addition of brush material had a positive effect on the seedling recruitment of transferred species and can thus clearly be recommended in our study system. The weak negative effect of grazing may not always justify fencing costs.

International audience; Industrial effluents discharged into the environment may have ecotoxic effects even if they come up to regulatory standards. Chemical evaluation of treatment performance by end-of-pipe treatment systems is thus not sufficient, especially when mixtures of metallic and organic contaminants are concerned. Given that contamination may alter biological characteristics of the environment, biomonitoring studies may provide information on integrated ecotoxical effects. However, there is a need for bioassays purpose-designed for direct use at industrial sites. Many biomonitoring tools already exist and have been proved to be efficient for evaluating the ecotoxicity of contaminated waters, but most of them require laboratory equipment. In this study, an experiment in microcosms under controlled conditions of pollution was carried out to assess the morphological responses of five helophytes exposed to mixtures of organic and/or metallic pollutants. The criteria of plant growth and development, i.e. aerial elongation and leaf senescence, that were the most relevant for reflecting the ecotoxicity of contaminant mixtures and that could be monitored on-site with a user-friendly method, were then selected. Focusing on these selected criteria, a new bioindicator tool, named the Helophyte Development Index (HDI), was created. Our results suggest that the HDI is a promising tool to use on-site for assessing the ecological state of waters released in aquatic environment by industrial factories, following the recommendations of the European Water Agency. (C) 2015 Elsevier B.V. All rights reserved.

International audience; After the examination of many specimens, the authors give new data on centipedes of the Mercantour National Park, the Alpes-Maritimes department and their surroundings. These examinations improve the knowledge of the distribution of several fairly rare species and allow to describe a remarkable new species from Entrevaux (Alpes-de-Haute-Provence department): Lithobius (Lithobius) lemairei n. sp. This new species occurs in superficial subterranean environments (MSS) and maybe deeper in caves or crevices; it exhibits morphological troglomorphic adaptations such as reduction of ocelli and an increased size of the Tomosvary's organ. It also has lateral-internal sulci on femora, tibiae, tarsi one and two of the 15th legs, and secondarily on the same articles of the 14th legs. These traits clearly distinguish this species from the others belonging to the genus Lithobius Leach, 1814 in this geographical area. After a reexamination of the published records and of the specimens recorded from the Alpes-Maritimes, Eupolybothrus (Eupolybothrus) fasciatus (Newport, 1845) must to be removed from the French. After our research of the halophilous and halobiontic species of geophilomorphs on the littoral of Alpes-Maritimes, it appears that these species have at least strongly declined in this area. An ecological synthesis is done on all the observed species, by cumulating the new data and the preceding contributions on the Alpes-Maritimes. A checklist of the centipedes known in the Mercantour National Park and/or in the Alpes-Maritimes department is given. It includes data on: 1) endemism at local and/or national level(s); 2) their presence in their limits of distribution; and 3) some remarkable ecological particularities (troglobiontic, halobiontic, orophilous species). Some local endemics and some stenoecious species seem to be potentially threatened, or even in a decline according to our observations. A preliminary list of these “vulnerables species” is proposed.

In the Mediterranean area, surface waters often have low discharge or renewal rates, hence metal contamination from industrialised catchments can have a high negative impact on the physico-chemical and biological water quality. In a context of climate and anthropological changes, it is necessary to provide an integrative approach for the prevention and control of metal pollution, in order to limit its impact on water resources, biodiversity, trophic network and human health. For this purpose, introduction of constructed wetlands (CWs) between natural aquatic ecosystems and industrialised zones or catchments is a promising strategy for eco-remediation. Analysis of the literature has shown that further research must be done to improve CW design, selection and management of wetland plant species and catchment organisation, in order to ensure the effectiveness of CWs in Mediterranean environments. Firstly, the parameters of basin design that have the greatest influence on metal removal processes must be identified, in order to better focus rhizospheric processes on specific purification objectives. We have summarised in a single diagram the relationships between the design parameters of a CW basin and the physico-chemical and biological processes of metal removal, on the basis of 21 mutually consistent papers. Secondly, in order to optimise the selection and distribution of helophytes in CWs, it is necessary to identify criteria of choice for the plant species that will best fit the remediation objectives and environmental and economic constraints. We have analysed the factors determining plant metal uptake efficiency in CWs on the basis of a qualitative meta-analysis of 13 studies with a view to determine whether the part played by metal uptake by plants is relevant in comparison with the other removal processes. Thirdly, we analysed the parameters to consider for establishing suitable management strategies for CWs and how they affect the whole CW design process. Finally, we propose monitoring and policy measures to facilitate the integration of CWs within Mediterranean industrialised catchments. Keywords: Constructed wetlands, Metal pollution, Plant species selection, Design methodologies, Management strategies, Industrialized Mediterranean Catchments

International audience; To counteract acidification of terrestrial ecosystems due to decades of acid atmospheric depositions two catchments were limed (2.5t ha(-1)) in fall 2003. Four years later, the effects of liming on soil macroinvertebrate community from both catchments were investigated by comparing the two limed catchments with two adjacent acidified control sites. During two seasons (fall and spring) and for each catchment, 21 samples of soil and litter-dwelling macroinvertebrates were extracted along a transect in order to evaluate the effect of liming on community structure. A canonical correspondence analysis (CCA) was used to evaluate which chemical soil factors could better explain the trends of structure changes of macroinvertebrate communities. Results showed that the taxonomic richness was not improved by liming. However, the total abundance was significantly lower for the two limed catchments as compared to control sites. Communities strongly differed as 42 taxa (52.2%) were different between the granite limed site and its adjacent control and 34 taxa (55.7%) on sandstone. The CCA revealed that liming affected soil communities mainly via changes in Ca concentration and soil pH which tended to favour some taxa such as Curculionidae while it exerted a negative effect on other zoological groups such as spiders that were preferentially found on control soils. These results tend to demonstrate that liming can be considered as a disturbance that have marked effects upon soil macro-invertebrate through species-dependant response to soil chemical changes.

International audience; We developed a synthetic index of biological soil quality (IBQS) based on soil macro-invertebrate community patterns to assess soil quality. In 22 sites representing the diversity of agroecosystems encountered in France, invertebrate communities co-varied significantly with a set of 14 parameters describing the physical and chemical properties of soil (co-inertia, p < 0.001; RV¼ 0.70). Using hierarchical classification, sites could be separated into four homogeneous groups and, using the 'indicator value' method, 46 indicator taxa characteristic of one or another of these groups were identified.We then used a formula that takes into account the abundance of indicator species and their respective indicator values to score soils from 1 to 20. IBQS was able to detect the effects of management practices on soil quality. Soil quality varied from 6 to 20 in forests, 7 to 9 in pastures and 2 to 9 in crops respectively. This suggests that well-managed crops and pastures may have better soil quality than some forests. Our results confirm that soil macro-invertebrates provide an integrative measure of soil quality and that the proposed index can be used either in short- or long-term monitoring, provided that it is calibrated and validated with respect to the regional context of the study.