72 research outputs found

    Quels objectifs de restauration pour un ancien polder de la basse vallée du Vistre ?

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    In areas deeply modified by human activities, the target ecosystems for restoration and/or rehabilitation projects can seldom be related to known reference systems accepted by all parties. Such projects are hence constructed around objectives defined with the owner according to a combination of biological, hydrological, social and political criteria. The rehabilitation on the Vistre marshes (Gard, France) was in such a way orientated by multiple objectives. The change of the fallow land towards a wetland with floodplain functions, a regional patrimonial value, can be considered a success. The area is dry by the end of summer and is filled annually by autumn floods. lt supports fish communities that attract fish eating birds. The colony of tree nesting herons is one of the most important of the region, and hosts a significant proportion of the French population of Squacco Heron (Ardeola ralloides). Moreover, it was turned into a Nature Reserve before the end of the project. However, a detailed analysis leads to a more critical evaluation of the multi-objective choice done initially. It led to abundant and costly monitoring studies that did not necessarily provide useful answers. It was for example not possible to conclude to what extent the area was a sink for nutrients. The need for social and economic studies was under-evaluated despite objectives of human use (hunting, grazing and reed harvesting). lt was concluded that such a project should be more strictly aimed to few targets, monitored and evaluated rigorously. Additional biological, hydrological, economical or social issues, in that case would be taken into account only when compatible with the priority objectives set. The initial choices have to be defined carefully and agreed upon by ali stakeholdersDans des zones fortement modifiées par les activités humaines, les systèmes visés par des projets de restauration et/ou de réhabilitation ne peuvent que rarement être définis par rapport à des écosystèmes de référence connus et acceptés par tous. Les projets sont donc construits autour d'objectifs déterminés avec les commanditaires selon des critères biologiques, hydrologiques, sociaux et politiques. La réhabilitation de marais dans la basse vallée du Vistre (Gard, France) a ainsi été orientée par de multiples objectifs. Le retour d'une friche agricole à une zone humide qui assure son rôle de plaine d'inondation, et qui a une valeur patrimoniale régionale, peut être considéré comme un succès. La colonie de hérons arboricoles y est une des plus importantes de la région et abrite une proportion significative de la population française de Héron crabier (Ardeola ralloides). L'analyse détaillée des divers aspects amène cependant à une évaluation plus critique du caractère multi-objectifs du projet qui a conduit à de nombreux suivis dont certains n'ont pas répondu aux questions posées. Il n'a pas été possible par exemple de conclure sur le caractère source ou puits pour les nutriments. L'importance des études sociales et économiques, malgré des objectifs d'usage, n'a pas été assez prise en compte. Nous concluons qu'un tel projet doit être centré sur peu d'objectifs, suivis et évalués avec rigueur, et qui auront été l'objet d'un consensus initial. Les autres demandes, biologiques, hydrologiques, économiques ou sociales, des acteurs et/ou commanditaires, ne seront prises en compte que si elles sont compatibles avec ces objectifs prioritaires et serviront surtout à définir les limites d'interventio

    The Plants of Mediterranean temporary pools: do we know enough for their conservation?

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    Mediterranean wetlands combine high conservation value and intense pressure from human activities and climate change. Temporary pools, which are important habitats for biodiversity in the Mediterranean region, are particularly exposed to destruction following their small size and depth. They show high species richness including many rare and specialized species, as well as high beta and gamma diversity resulting from the range of environmental conditions they encompass

    6. Peatland Conservation

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    Expert assessors Stephanie Boudreau, Canadian Sphagnum Peat Moss Association, Canada Emma Goodyer, IUCN UK Peatlands Programme, UK Laura Graham, Borneo Orangutan Survival Foundation, Indonesia Richard Lindsay, University of East London, UK Edgar Karofeld, University of Tartu, Estonia David Locky, MacEwan University, Canada Nancy Ockendon, University of Cambridge, UK Anabel Rial, Independent Consultant & IUCN Species Survival Commission, Colombia Sarah Ross, Penny Anderson Associates, UK Nigel..

    Bellis prostrata Pomel (Asteraceae), a new species for Morocco

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    Investigations conducted in temporary wetlands of the coastal Meseta of W Morocco (Benslimane region) lead to the discovery of Bellis prostrata in a small endoreic temporary pool (ca. 1 ha) of the quartzitic-limestone plateau of Benslimane

    Seventeen ‘extinct’ plant species back to conservation attention in Europe

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    Seventeen European endemic plant species were considered extinct, but improved taxonomic and distribution knowledge as well as ex situ collecting activities brought them out of the extinct status. These species have now been reported into a conservation framework that may promote legal protection and in situ and ex situ conservation.info:eu-repo/semantics/publishedVersio

    Puntos de inflexión en los gradientes de composición de las comunidades de plantas acuáticas de diferentes continentes

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    Unravelling patterns and mechanisms of biogeographical transitions is crucial if we are to understand compositional gradients at large spatial extents, but no studies have thus far examined breakpoints in community composition of freshwater plants across continents. Using a dataset of almost 500 observations of lake plant community composition from six continents, we examined, for the first time, if such breakpoints in geographical space exist for freshwater plants and how well a suite of ecological factors (including climatic and local environmental variables) can explain transitions in community composition from the subtropics to the poles. Our combination of multivariate regression tree (MRT) analysis and k-means partitioning suggests that the most abrupt breakpoint exists between temperate to boreal regions on the one hand and freshwater plant communities harbouring mainly subtropical or Mediterranean assemblages on the other. The spatially structured variation in current climatic conditions is the most likely candidate for controlling these latitudinal patterns, although one cannot rule out joint effects of eco-evolutionary constraints in the harsher high-latitude environments and post-glacial migration lags after Pleistocene Ice Ages. Overall, our study supports the foundations of global regionalisation for freshwater plants and anticipates further biogeographical research on freshwater plant communities once datasets have been harmonised for conducting large-scale spatial analyses.publishedVersio

    A More Effective Ramsar Convention for the Conservation of Mediterranean Wetlands

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    The Ramsar Convention is the multilateral agreement aimed at protecting wetlands globally. Wetlands are particularly recognized for their role in the Mediterranean biodiversity hotspot by providing key habitats for endemic and migratory species, directly contributing benefits to the lives of people and being an integral part of their culture. In response to this importance, the Mediterranean Wetlands Observatory publishes Mediterranean Wetland Outlooks (MWOs) on the state and trends of Mediterranean wetlands; the first edition in 2012 (MWO1) and the second edition in 2018 (MWO2). In this paper, we used the results of the two Mediterranean Wetland Outlooks to highlight ways to increase the impact of the Ramsar Convention by identifying the spatial dimensions of detected biodiversity trends as well as the societal developments and estimated impacts of global change and protection status
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