60 research outputs found

    Les enjeux de l’équivalence écologique pour la conception et le dimensionnement de mesures compensatoires d’impacts sur la biodiversité et les milieux naturels,

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    L’évolution du contexte réglementaire a renforcé l’obligation de compenser " en nature " les impacts sur la biodiversité qui n’ont pas pu être évités ou réduits. Dans ce contexte, l’évaluation de l’équivalence entre les pertes causées par ces impacts et les gains de biodiversité attendus des actions de compensation suscite des questions scientifiques et techniques quant aux concepts et connaissances à mobiliser et aux méthodes d’évaluation à développer et mettre en ½uvre. On y trouve en particulier l'identification des éléments de biodiversité à considérer, le développement d’indicateurs appropriés permettant de comparer pertes et gains, la sélection d’un état de référence pour le calcul des pertes et gains, et la prise en compte des dynamiques écologiques et des incertitudes dans l’évaluation du devenir des sites de compensation. Par ces questions, l'équivalence écologique donne un cadre de raisonnement explicite à la conception et au dimensionnement de la compensation qui est appropriable par chacun des acteurs concernés. / Since 2007 France has seen a radical strengthening of its legislation concerning the mitigation of development impacts on biodiversity and ecosystems. Under pressure from the European Union and as an outcome of a national consultative process called the “Grenelle de l’Environnement”, the scope of the mitigation hierarchy of avoiding, reducing and offsetting impacts of plans, programs and projects has been expanded. It now includes stronger requirements in terms of monitoring and effective implementation. These changes – which have strong financial and legal implications for developers - have revealed the lack of technical guidelines for designing and sizing offsets. Assessing the ecological equivalence between losses caused by impacts and the gains expected from offset actions raises scientific and technical issues that remain unresolved. These include the identification of relevant components of biodiversity, the development of appropriate indicators, the identification of reference states and the incorporation of ecological dynamics and uncertainties into offset design and sizing

    New handbook for standardised measurement of plant functional traits worldwide

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    Importance and intensity of competition along a fertility gradient and across species

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    International audienceQuestions: 1. Can the importance and the intensity of competition vary independently along a nutrient gradient? 2. Are these variations species dependent? Location: Sub-alpine pastures of the northern French Alps. Methods: Competition intensity measures how much competition decreases the performances of an organism. Competition importance measures how much competition contributes to affect performance, among other processes (such as environmental stress or disturbance). Competition intensity and importance were measured on three co-occurring species: Festuca rubra, a perennial grass, and two forbs of contrasting basal area, Chaerophyllum hirsutum and Alchemilla xanthochlora. A neighbour removal experiment was performed on Festuca rubra in three sub-alpine grassland communities differing in fertility and on Chaerophyllum hirsutum and Alchemilla xanthochlora in the two more fertile of these communities. The importance of competition was quantified using an index proposed by Brooker et al. (2005). Results: Competition intensity and importance showed different patterns of variation along the fertility gradient for Festuca rubra: competition importance decreased with decreasing fertility whereas competition intensity did not change. The largest forb was the least affected by competition. Our results suggest that the importance of competition for all three species depended on their individual tolerance to low nutrient availability. Conclusions: 1. The distinction between the importance and the intensity of competition is helpful to explain conflicting results obtained on the variations of competition indices along productivity gradients. 2. The choice of a phytometer can affect the conclusions drawn from empirical studies

    Zones humides et sports d'hiver dans les Alpes françaises : enjeux et idées innovantes pour la préservation des zones humides au sein des domaines skiables

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    International audienceThis presentation is a synthesis of a symposium held last October in Cemagref, Grenoble with contributions from scientists as well as lift operators, NGO's, and administrations. In the context of global change, ski resorts must rethink their development models.The diversification of the touristic offer is encouraged and thespecificity of the mountain territory is at the heart of a sustainable development. In this context, the preservation of interesting and fragile habitats such as wetlands is topical. Wetlands have many recognized functions: flooding reduction, water remediation, fertilization, biodiversity conservation... In mountain areas, wetlands are small and scattered. They are of special interest in particular for their role in biodiversity conservation and for their cultural and recreational benefits. However, in ski areas, wetlands can interact with the ski activity. Indeed, wetlands can speed up snow melting in spring and they often occupy ledges, which are strategic positions for the establishment of ski resort's facilities. The development of ski resorts can lead to the destruction or the deterioration of wetlands because of hydrologic interferences, fill in, pollution, etc. However, a few judicious steps can be taken to reduce or suppress these negative effects. In the Alps, geographical and administrative tools have been developed to help the decisions of ski-resort's administrators. Meetings between lift-operators, administrators of protected areas scientists and NGO's have also proved efficient when done at an early stage of a project, as shown by the example of the ski-resortLes Saisies

    IgM autoantibodies to 180- and 230- to 240-kd human epidermal proteins in pregnancy

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    BACKGROUND AND DESIGN: A previous study has suggested that there is a novel entity among the polymorphous eruptions of pregnancy (PEP) associated with circulating anti-basement membrane zone IgM autoantibodies. To determine if the presence of anti-basement membrane zone IgM autoantibodies is a feature of PEP, serum samples from 52 patients with a PEP, 69 healthy pregnant women, and 42 nonpregnant women were prospectively evaluated by indirect immunofluorescence using salt-split human skin as substrate. Serum samples were also tested by immunoblotting using keratinocyte extracts and anti-human IgM antibodies. The reactivity of some serum samples was examined using two recombinant bullous pemphigoid antigen proteins. RESULTS: The percentage of women with a PEP, healthy pregnant women, and nonpregnant women who had anti-basement membrane zone IgM antibodies by indirect immunofluorescence was similar: 12%, 10%, and 14% of cases, respectively. By immunoblotting, 14% of the serum samples from the patients with a PEP, 12% of the serum samples from the healthy pregnant women, but only 2% of the serum samples from the nonpregnant women contained IgM antibodies that reacted with epidermal proteins of 180 and/or 230 to 240 kd. The recombinant bullous pemphigoid antigen proteins were not recognized by any of the serum samples that showed a reactivity by immunoblotting using keratinocyte extracts. CONCLUSION: There is no evidence for the existence of a novel entity of pregnancy defined by circulating anti-basement membrane zone IgM autoantibodies. Immunoblotting detects IgM autoantibodies that react with epidermal proteins of 180 and/or 230 to 240 kd. These autoantibodies appear to be more frequent in pregnant than in nonpregnant women. Although the nature of the target antigen(s) remains to be established, pregnancy may be associated with low levels of IgM autoreactivity against epidermal proteins

    Le vécu de la prise en charge en salle de naissance ::une étude qualitative comparative

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    Le but de cette étude était d’étudier le vécu des mères insatisfaites de la prise en charge en salle de naissance en le comparant avec celui de mères satisfaites, à partir des données recueillies par évocations hiérarchisées dans l’Étude du Vécu de l’Accouchement (EVA). Il s’agissait d’une étude qualitative, contrôlée par témoins, en population, réalisée au sein de 25 maternités françaises d’un même territoire (Réseau AURORE). Les expressions recueillies par l’évocation hiérarchisée, appelées verbatim, ont été regroupées en sous-thèmes, thèmes et méta-thèmes. Le critère principal de jugement était le pourcentage de patientes ayant cité au moins un mot appartenant à un sous-thème. Six cent quarante-deux mères ont été incluses dans l’étude EVA. Soixante et onze mères ont répondu « insuffisamment » et/ou « pas du tout » à au moins un des items du questionnaire de satisfaction. Elles ont toutes été incluses dans notre étude et constituaient le groupe de cas (insatisfaites). Le groupe témoin (satisfaites) appariés comprenait 144 mères. Le sous-thème de la peur a été significativement plus évoqué par le groupe de mères insatisfaites que par le groupe témoin (42 versus 22 %, p = 0,02). Concernant le sous-thème de la douleur, aucune différence significative n’a été observée entre les deux groupes (45 versus 33 %, p = 0,09). Les résultats incitent à porter plus d’attention à la réassurance des mères en salle de naissance. Identifier les mères inquiètes en cours de grossesse et au moment de l’accouchement doit être une priorité pour les soignants.The objective of our study was to analyze the experience of childbirth care in the delivery room of unsatisfied mothers by comparing it to satisfied mothers. The data was collected using the hierarchical evocation method from the EVA study (Étude du Vécu de l’Accouchement). It was a comparative qualitative study carried out in 25 French maternity hospitals (Réseau AURORE). The words collected using the hierarchical evocation method, called verbatim, have been regrouped into sub-themes, themes and metathemes. The primary outcome was the percentage of mothers who quoted at least one word belonging to a sub-theme. Six hundred and forty-two mothers were included in the EVA study. Seventy-one mothers reported dissatisfaction and they were included in our study. A control group was formed with 144 satisfied mothers selected on a propensity score. The contextual element that emerges as significantly associated with the declaration of dissatisfaction is the fear expressed by 42% of the mothers declaring themselves dissatisfied, compared to 22% of those declaring themselves satisfied with childbirth care (P = 0.02). Regarding the sub-theme of pain, there was no significant difference between the two samples (45 versus 33%, P = 0.09). The results suggest that more attention should be paid to preparing and reassuring mothers in the delivery room. The identification of fear during pregnancy and childbirth should be a priority for the caregivers
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