5 research outputs found

    Benefits of protected areas for nonbreeding waterbirds adjusting their distributions under climate warming

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    Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993-2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming

    Les services culturels récréatifs et éducatifs des zones humides en Méditerranée : des services sous-estimés malgré les avantages qu'ils procurent, résultats d'études en Méditerranée

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    Cette synthĂšse donne un aperçu des principaux rĂ©sultats et analyses des Ă©tudes conduites en France et au Maghreb entre 2012 et 2014 sur les services culturels rĂ©crĂ©atifs et Ă©ducatifs que procurent les zones humides mĂ©diterranĂ©ennes. L'Observatoire des zones humides mĂ©diterranĂ©ennes (OZHM), gĂ©rĂ© par la Tour du Valat dans le cadre de l'initiative mĂ©diterranĂ©enne de Ramsar (MedWet), en a coordonnĂ© le travail. En partenariat avec l'Institut Agronomique MĂ©diterranĂ©en de Montpellier (IAMM), la synthĂšse des neuf sites Ă©tudiĂ©s a Ă©tĂ© rĂ©alisĂ©e en 2015, ce qui a permis une premiĂšre analyse rĂ©gionale et sous-rĂ©gionale. Ce travail a aussi pour vocation d'Ă©tablir un premier Ă©tat de rĂ©fĂ©rence qualitatif utile pour les suivis ultĂ©rieurs. Ce travail n'aurait pas pu ĂȘtre rĂ©alisĂ© sans la participation active des gestionnaires et associations des neufs sites Ă©tudiĂ©s et des institutions publiques qui ont facilitĂ© le travail: la Direction gĂ©nĂ©rale des ForĂȘts en AlgĂ©rie et en Tunisie et le Haut Commissariat des Eaux et ForĂȘts et de la Lutte contre la DĂ©sertification au Maroc

    Imputation of incomplete large‐scale monitoring count data via penalized estimation

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    In biodiversity monitoring, large datasets are becoming more and more widely available and are increasingly used globally to estimate species trends and conservation status. These large-scale datasets challenge existing statistical analysis methods, many of which are not adapted to their size, incompleteness and heterogeneity. The development of scalable methods to impute missing data in incomplete large-scale monitoring datasets is crucial to balance sampling in time or space and thus better inform conservation policies. We developed a new method based on penalized Poisson models to impute and analyse incomplete monitoring data in a large-scale framework. The method allows parameterization of (a) space and time factors, (b) the main effects of predictor covariates, as well as (c) space–time interactions. It also benefits from robust statistical and computational capability in large-scale settings. The method was tested extensively on both simulated and real-life waterbird data, with the findings revealing that it outperforms six existing methods in terms of missing data imputation errors. Applying the method to 16 waterbird species, we estimated their long-term trends for the first time at the entire North African scale, a region where monitoring data suffer from many gaps in space and time series. This new approach opens promising perspectives to increase the accuracy of species-abundance trend estimations. We made it freely available in the r package ‘lori’ (https://CRAN.R-project.org/package=lori) and recommend its use for large-scale count data, particularly in citizen science monitoring programmes

    Gap analysis of the Ramsar site network at 50: over 150 important Mediterranean sites for wintering waterbirds omitted

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    The Mediterranean Basin is a biodiversity hotspot. Wetlands make a key contribution to this status, but many of them remain outside the Ramsar network fifty years after the establishment of the Ramsar Convention. Here we evaluate the extent to which the Mediterranean Ramsar network covers wetlands of international importance for wintering waterbirds using the Ramsar Convention criteria 2 (species of conservation concern), 5 (> 20,000 waterbirds) and 6 (1% of a population). These criteria were applied to 4186 sites in 24 Mediterranean countries using counts of 145 wintering waterbird species from 1991 to 2017. We identified 161 sites of international importance for waterbirds that have not yet been declared as Ramsar sites, which could be added to the 180 current Mediterranean Ramsar sites established based on waterbird criteria (criteria 5 and/or 6). Among these sites, a subset of 32 very important sites reached double the required level for at least one criterion and 95 were not protected by any site conservation status. Coastal wetlands represented half of the Ramsar gap for waterbirds. We identified that an additional 1218 monitored sites could be provisionally considered as internationally important and thus require more survey efforts to assess their status. This study highlights a lack of participation of the Mediterranean countries to build the Ramsar network for wetland protection. Our results should help policymakers and managers to prioritize future Ramsar site designation, notably in the Middle East and Western European region where important gaps were identified

    Abstracts of 1st International Conference on Computational & Applied Physics

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    This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria
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