687 research outputs found

    Has the common genet (Genetta genetta) spread into south-eastern France and Italy ?

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    The common genet (Genetta genetta) is a small carnivoran that was probably introduced from Maghreb into south-western Europe. We reassessed its easternmost European distribution from 110-mostly new-data collected in south-eastern France and Italy, and tested for potential habitat selection, to finally re-evaluate the role of the Rhone as a geographic barrier against eastward migrations. The species was more frequent in river valleys, wetlands and low-mountainous areas (south-eastern France), but also occurred in high-mountainous zones at the French-Italian border. Our results evidenced a significant increase of records (13-fold the number of occurrences previously known) and an apparent absence of habitat selection by the common genet, suggesting a recent, natural spread from the right bank of the Rhne through a zone of 30km with artificial bridges. We finally provide a synthetic, re-assessed distribution map of the common genet in France and Italy, combining 4317 occurrences from French national databases and the 110 records collected herein

    Suspended SU-8 structures for monolithic microfluidic channels

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    SU-8 photoresist is commonly used in the field of microfabrication as structural material or for molding of microfluidic devices. One major limitation, however, is the difficulty to process partially freestanding SU-8 structures or monolithic closed cavities and channels on-chip. We propose here a simple method for the fabrication of suspended structures, in particular of monolithic SU-8 microchannels. The method is based on the processing of a SU-8 double-layer. Appropriate modification of the optical properties of the upper layer allows for selective crosslinking in the layer sandwich. This process is suitable for versatile layouts comprising open and hollow SU-8 structures on the same chi

    The role of urban structures in the distribution of wasteland flora in the Greater Paris Area, France

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    International audienceWastelands are likely to host a significant part of urban floristic diversity but have received limited attention because they are not considered interesting green zones. Here, we explore the potential role of wastelands in maintaining urban biodiversity to help define effective urban management plans. We quantified floristic diversity in 98 wasteland sites of Hauts-de-Seine, one of the most densely populated areas in France, and characterized the environmental parameters and spatial distribution of sites to identify some of the factors that influence plant species composition and to explore the impact of urban environment on the floristic interest of wastelands. Their floristic richness represented 58% of the total richness observed in the whole study area. Site richness depended on site area (the largest sites were the richest) and site age, with a maximum in sites of intermediate age (4-13 years). In the largest sites only (>2,500 m 2), the floristic distance among sites was positively correlated with geographic distance, which suggests that migration of species among large sites partly controls local floristic composition. In contrast, the environmental distance among sites was not correlated with floristic distance. Finally, we showed that the presence of collective and individual dwellings within 200 m of a wasteland decreased its floristic rarity, whereas the presence of rivers or ponds increased it. We derive several recommendations to optimize the management of wastelands with respect to conservation of urban biodiversity

    INNOVATION RIGIDITY AND ECOLOGICALECONOMIC RECONCILIATION IN AGRICULTURE

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    N° ISBN - 978-2-7380-1284-5International audienceFor several decades, significant changes in bird biodiversity have been reported, especially in Europe. Agriculture, and more specifically agricultural intensification, is a major driver of these modifications. Taking into account these environmental impacts, agriculture nowadays aims at a more sustainable way of producing which would reconcile its economic and ecological functions. The objective of this paper is to give insights into the impact of public policies and financial incentives on both the conservation of biodiversity and farming production. We therefore develop a macro-regional model combining a community dynamics of 65 bird species impacted by agricultural land-use and an economic decision model for each French region. The ecological dynamic model is calibrated with the STOC (Time Survey of Common Birds) and AGRESTE (French land-uses) databases while the economic model relies on the optimization of the gross margin of the RICA (Network of Agricultural Accountant Information). We investigate different scenarios based on subsidies and taxes to study the impact of public policies on both biodiversity and agricultural economics. We show that simple economic instruments could be used to establish scenarios promoting economic performance and bird populations. The bio-economical analysis shows several solutions for the ecology-economy trade-off. These results suggest that many possibilities are available to develop multi-functional sustainable agriculture. We focus here on the impact of the innovation rigidity and we show that a too big innovation ability is not necessary favourable to the biodiversity because of the inertia of the biological systems

    Analysis of Spatial and Temporal Variations of High Nature Value Farmland and Links with Changes in Bird Populations: A Study on France

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    The 'High Nature Value farming' idea connects the preservation of biodiversity with the need to safeguard the continuation of farming in certain areas and the maintenance of specific farming systems associated with a long-term management approach. The need for measures to prevent the loss of High Nature Value farmland is widely acknowledged. Conservation of biodiversity on agricultural land is an explicit objective of the pan-European Biodiversity and Landscape Strategy, the Bern Convention and, at EU level, the Habitats and Birds Directives and the Rural Development Policy (Community Strategic Guidelines for Rural Development Programming Period 2007-2013). Conserving High Nature Value farmland is a key aspect in achieving future biodiversity targets. In their 2003 ¿Kyiv¿ declaration, the European Environment Ministers have set the goal to identify HNV farmland in Europe and take adequate conservation measures. The COM(2010) 4 final ¿Options for an EU vision and target for biodiversity beyond 2010¿ recognises the need of preserving and enhancing farming and forestry with a high nature value in the context of the CAP. Furthermore, in 2006 the frame of agri-environmental indicators for monitoring the integration of environmental concerns into the common agricultural policy has been formally identified and published in the COM (2006) 508. The High Nature Value farmland indicator is part of the framework, as well as indicators on Population trends in farmland birds. JRC/IES is one of the EC services that are developing such indicators. The aim of this study is to improve the methodology to define HNV farmland areas and investigate more thoroughly the link between bird species and farmland habitat. The French case study is presented in high detail; relevant statistical data were available regarding agriculture practices both at present and past time periods, which provided the information for the development of a national HNV indicator. Data from the French Breeding Bird Census have been used to seek for links between bird species and bird indices, and spatial and temporal distribution of HNV farmland.JRC.DDG.H.5-Rural, water and ecosystem resource

    Community richness and stability in agricultural landscapes: the importance of surrounding habitats

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    Abstract In this paper, the role played by habitat diversity in the landscape on species richness and on the stability of farmland bird communities was investigated. Species richness was estimated on 374 samples monitored in farmland by the French breeding bird survey during the 2001-2005 period. A capture-recapture approach was used to estimate species richness accounting for the variation in detection probability among species of the 100 most common species detected in farmland. Landscape structure and composition were measured both in farmland and in adjacent habitats. The independent effect of each variable on community richness and stability was further assessed using hierarchical variance partitioning and taking spatial autocorrelation into account. A strong matrix effect was detected: non-cropped land deeply influenced richness and stability of bird assemblages.

    Identification of High Nature Value Farmland in France through Statistical Information and Farm Practices Surveys

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    The Concept of High Nature Value (HNV) farmland has been evolving over the last fifteen years in Europe. In the European Union this has been closely linked to the aim of integrating environmental concerns in the Common Agricultural Policy. The idea that nature values, environmental qualities, even cultural heritage are linked to or dependent on farming, also underlies and supports the concept of a multifunctional 'European model of farming' which provides benefits other than food. The 'High Nature Value farming' idea thus ties the preservation of biodiversity and wildlife value of the countryside to the need to safeguard the continuation of farming in certain areas with maintenance of specific farming systems associated to the long-term management of these areas. The work presented in the report aims at better identifying and characterising HNV farmland at national level (France) with a farm system approach based on FSS statistical data and specific national surveys, taking into account the whole farm with the total agricultural area and its characteristics. In a first step relevant variables have been selected to calculate the “crop diversity” indicator at NUTS 5. In a second step the crop diversity indicator has been combined overlaid with other data sets from other surveys (“Grassland” Survey and “Forestry” Survey) to build “the landscape elements” and “the extensive crops and grasslands” indicators. In a third step these three indicators have been weighted to calculate a final score and draw maps at municipality scale (NUTS 5).JRC.H.5-Rural, water and ecosystem resource

    How does the economic risk aversion affect biodiversity?

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    The present paper analyses the role played by risk aversion in the reconciling of agricultural income and biodiversity. A bio-economic mode which articulates bird community dynamics and representative farmers selecting land uses within an uncertain macro-economic context is developed. It is spatialized and calibrated at a regional scale for France through national databases. The impact of risk aversion is assessed on economic, agricultural and ecological outputs through projections at the 2050 horizon. A high enough aversion proves sufficient to promote global bio-economic performance and multi-functional agriculture. This occurs through a diversification mechanism on regional land-uses. Spatial disparities however suggest that public incentives could be necessary to reinforce the diversification and bio-economic effectiveness.Agriculture, Aversion, Bio-economic modeling, Bird, Biodiversity, Diversification, Public good, Spatial

    Impacts of global change on species distributions: obstacles and solutions to integrate climate and land use

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    Aim The impact of multiple stressors on biodiversity is one of the most pressing questions in ecology and biodiversity conservation. Here we critically assess how often and efficiently two main drivers of global change have been simultaneously integrated into research, with the aim of providing practical solutions for better integration in the future. We focus on the integration of climate change (CC) and land-use change (LUC) when studying changes in species distributions. Location Global. Methods We analysed the peer-reviewed literature on the effects of CC and LUC on observed changes in species distributions, i.e. including species range and abundance, between 2000 and 2014. Results Studies integrating CC and LUC remain extremely scarce, which hampers our ability to develop appropriate conservation strategies. The lack of CC-LUC integration is likely to be a result of insufficient recognition of the co-occurrence of CC and LUC at all scales, covariation and interactions between CC and LUC, as well as correlations between species thermal and habitat requirements. Practical guidelines for the study of these interactive effects include considering multiple drivers and processes when designing studies, using available long-term datasets on multiple drivers, revisiting single-driver studies with additional drivers or conducting comparative studies and meta-analyses. Combining various methodological approaches, including time lags and adaptation processes, represent further avenues to improve global change science. Main conclusions Despite repeated claims for a better integration of multiple drivers, the effects of CC and LUC on species distributions and abundances have been mostly studied in isolation, which calls for a shift of standards towards more integrative global change science. The guidelines proposed here will encourage study designs that account for multiple drivers and improve our understanding of synergies or antagonisms among drivers
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