Résumé
The congruence of ecosystem services (ESs) and the congruence of ES ‘hotspots’ and ‘hotspots’ of biodiversity are receiving growing interest. The thresholds used in such analyses to assess the ES presence vary widely but their effects have not been questioned. We provide an analysis of the effect of the choice of these thresholds on the overlap among ESs and the distribution of hotspots. Focusing on grasslands from the Central French Alps, we first systematically varied thresholds for three ESs (agronomic, regulation and aesthetic values), then considered triplets of thresholds representing three contrasted stakeholder perspectives on the importance of each of these services. Overlap between ESs depended strongly on thresholds. The extent of ES hotspots and their overlap with biodiversity hotspots varied widely across perspectives. Coldspots never overlapped with areas of interest for biodiversity, whatever be the perspective. Overlap was less informative than the diagnostic test of the capacity of individual ESs to capture each other's distribution. Agronomic value poorly captured other ESs. Biodiversity was well captured by regulation and aesthetic values, but poorly captured by service hotspots. This analysis emphasizes the importance of accounting for varying stakeholders' expectations in ES hotspot assessments.
Auteurs, date et publication :
Auteurs Pierre Gos , Sandra Lavorel
Publication : International Journal of Biodiversity Science, Ecosystem Services & Management
Date : 2012
Volume : 8
Issue : 1-2
Pages : 93-106
Catégorie(s)
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Functional variability (FV) of populations can be decomposed into three main features: the individual variability of multiple traits, the strength of correlations between those traits and the main direction of these correlations, the latter two being known as ‘phenotypic integration’. Evolutionary biology has long recognized that FV in natural populations is key to determining potential evolutionary responses, but this topic has been little studied in functional ecology. Here, we focus on the arctico-alpine perennial plant species Polygonum viviparum L.. We used a comprehensive sampling of seven functional traits in 29 wild populations covering the whole environmental niche of the species. The niche of the species was captured by a temperature gradient, which separated alpine stressful habitats from species-rich, competitive subalpine ones. We sought to assess the relative roles of abiotic stress and biotic interactions in shaping different aspects of functional variation within and among populations, that is, the multi-trait variability, the strength of correlations between traits and the main directions of functional trade-offs. Populations with the highest extent of functional variability were found in the warm end of the gradient, whereas populations exhibiting the strongest degree of phenotypic integration were located in sites with intermediate temperatures. This could reveal both the importance of environmental filtering and population demography in structuring FV. Interestingly, we found that the main axes of multivariate functional variation were radically different within and across population. Although the proximate causes of FV structure remain uncertain, our study presents a robust methodology for the quantitative study of functional variability in connection with species' niches. It also opens up new perspectives for the conceptual merging of intraspecific functional patterns with community ecology.
Auteurs, date et publication :
Auteurs Florian C. Boucher , Wilfried Thuiller , Cindy Arnoldi , Cécile H. Albert , Sébastien Lavergne
Publication : Functional Ecology
Date : 2025
Volume : 27
Issue : 2
Pages : 382-391
Catégorie(s)
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Species enter and persist in local communities because of their ecological fit to local conditions, and recently, ecologists have moved from measuring diversity as species richness and evenness, to using measures that reflect species ecological differences. There are two principal approaches for quantifying species ecological differences: functional (trait-based) and phylogenetic pairwise distances between species. Both approaches have produced new ecological insights, yet at the same time methodological issues and assumptions limit them. Traits and phylogeny may provide different, and perhaps complementary, information about species' differences. To adequately test assembly hypotheses, a framework integrating the information provided by traits and phylogenies is required. We propose an intuitive measure for combining functional and phylogenetic pairwise distances, which provides a useful way to assess how functional and phylogenetic distances contribute to understanding patterns of community assembly. Here, we show that both traits and phylogeny inform community assembly patterns in alpine plant communities across an elevation gradient, because they represent complementary information. Differences in historical selection pressures have produced variation in the strength of the trait-phylogeny correlation, and as such, integrating traits and phylogeny can enhance the ability to detect assembly patterns across habitats or environmental gradients.
Auteurs, date et publication :
Auteurs Marc Cadotte , Cecile H. Albert , Steve C. Walker
Publication : Ecology Letters
Date : 2025
Volume : 16
Issue : 10
Pages : 1234-1244
Catégorie(s)
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Auteurs Patrick Saccone , Samuel Morin , Florence Baptist , Jean-Marc Bonneville , Marie-Pascale Colace , Florent Domine , Mathieu Faure , Roberto Geremia , Jonathan Lochet , Franck Poly , Sandra Lavorel , Jean-Christophe Clément
Publication : Plant and Soil
Date : 2025
Volume : 363
Issue : 1-2
Pages : 215-229
Catégorie(s)
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Mountain grassland ecosystems are particularly vulnerable to direct climate impacts and to indirect climate change impacts through farmers’ management adaptation. We modelled expected spatio-temporal trajectories of land management of a mountain grassland landscape in the French Alps under a range of short-term climate and socio-economic scenarios which were constructed using an advanced participatory approach with a variety of stakeholders. First, regional experts from nature conservation and agricultural extension were involved in the co-development of detailed qualitative climate and socioeconomic scenarios, expressed as coherent storylines. Second, to map land management adaptation to these storylines, we used a role playing game whereby farmers were put in an imaginary future situation and asked to make decisions under scenario constraints. For each scenario, game outcomes were used to map future land management at parcels to landscape scales. Main adaptations were conversion from mowing to grazing and increasing manured area, with varying proportions and locations for these two types of changes differing across scenarios, though overall small. These results highlight the limited adaptability of current farmers given a strongly constraining natural and social context. Beyond research outputs, this framework generated interesting outcomes for stakeholders and raised their awareness about the socio-ecological system’s vulnerability to future changes.
Auteurs, date et publication :
Auteurs Pénélope Lamarque , Aloïs Artaux , Cécile Barnaud , Laurent Dobremez , Baptiste Nettier , Sandra Lavorel
Publication : Landscape and Urban Planning
Date : 2025
Volume : 119
Pages : 147-157
Catégorie(s)
#CNRS #Lautaret #UGARésumé
The airborne plant pathogenic bacterium Pseudomonas syringae is ubiquitous in headwaters, snowpack and precipitation where its populations are genetically and phenotypically diverse. Here, we assessed its population dynamics during snowmelt in headwaters of the French Alps. We revealed a continuous and significant transport of P. syringae by these waters in which the population density is correlated with water chemistry. Via in situ observations and laboratory experiments, we validated that P. syringae is effectively transported with the snow melt and rain water infiltrating through the soil of subalpine grasslands, leading to the same range of concentrations as measured in headwaters (102–105 CFU l−1). A population structure analysis confirmed the relatedness between populations in percolated water and those above the ground (i.e. rain, leaf litter and snowpack). However, the transport study in porous media suggested that water percolation could have different efficiencies for different strains of P. syringae. Finally, leaching of soil cores incubated for up to 4 months at 8°C showed that indigenous populations of P. syringae were able to survive in subalpine soil under cold temperature. This study brings to light the underestimated role of hydrological processes involved in the long distance dissemination of P. syringae.
Auteurs, date et publication :
Auteurs Caroline L. Monteil , François Lafolie , Jimmy Laurent , Jean-Christophe Clement , Roland Simler , Yves Travi , Cindy E. Morris
Publication : Environmental Microbiology
Date : 2025
Volume : 16
Issue : 7
Pages : 2038-2052
Catégorie(s)
#CNRS #Lautaret #UGARésumé
High-alpine geomorphosites are poorly understood and developed, mostly because of the heavy constraints of high mountain areas. Meanwhile, they are geoheritage areas that are often extremely vulnerable to global warming: glaciers and permafrost areas are currently affected by major changes due to increasing air temperature. To deal with the high spatial variability of landforms and processes, research on alpine geomorphosites often needs the use of advanced methods of high-resolution topography, among which terrestrial laser scanning plays an increasingly crucial role. Carried out on some tenth of high-elevation sites across the Alps since the beginning of the 2000s, this method is particularly interesting for the recognition and development of high-alpine geomorphosites. Indeed, it can be implemented for identifying and characterizing the geomorphic objects (survey, monitoring and mapping), helping planning and protection policies and serving geotouristic development (communication about the processes involved, basis for documents).
Auteurs, date et publication :
Auteurs L. Ravanel , X. Bodin , P. Deline
Publication : Geoheritage
Date : 2025
Volume : 6
Issue : 2
Pages : 129-140
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Marie-Lise Benot , Patrick Saccone , Emmanuelle Pautrat , Rachel Vicente , Marie-Pascale Colace , Karl Grigulis , Jean-Christophe Clément , Sandra Lavorel
Publication : Ecosystems
Date : 2025
Volume : 17
Issue : 3
Pages : 458-472
Catégorie(s)
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Mountain regions are key for humanity's water supply, and their water yield depends on climatic, soil and vegetation effects. Here we explore the effects of vegetation composition and structure on the water balance of high elevation grasslands with different climatic conditions across the Alps. Using a total of 220 deep seepage collectors with intact soil-vegetation monoliths in different types of mountain grasslands in the Austrian, French and Swiss Alps, we solved the water balance equation for evapotranspiration (ET) and related the results to biomass, the abundance of certain plant functional types and structural and functional vegetation properties. While daily mean ET during the growing season was similar at all sites, ET to precipitation ratios were significantly higher and ET to potential ET ratios significantly lower at the drier French sites than at the more humid Swiss and Austrian site. Large variability of ET, seepage and soil moisture within all sites pointed at a high influence of vegetation on the water balance. While ET increased significantly with biomass at all sites, the influence of other vegetation properties was site specific. At the more humid, subalpine Austrian site the effects of vegetation on ET were stronger and more diverse than at the higher elevation Swiss site and the drier French sites, where climatic drivers dominated ET. The potential to influence ET and water yield of mountain areas by manipulating the plant canopy with systematic land management is therefore higher in regions with good growing conditions than in areas with harsh climate. Copyright © 2014 John Wiley & Sons, Ltd.
Auteurs, date et publication :
Auteurs N. Obojes , M. Bahn , E. Tasser , J. Walde , N. Inauen , E. Hiltbrunner , P. Saccone , J. Lochet , J. C. Clément , S. Lavorel , U. Tappeiner , Ch Körner
Publication : Ecohydrology
Date : 2025
Volume : 8
Issue : 4
Pages : 552-569
Catégorie(s)
#CNRS #Lautaret #UGARésumé
Recent observations and geodetic measurements in the European Alps show that changes are occurring on rock glacier dynamics, ranging from moderate velocity variations to strong acceleration or even total collapse. These changes can be related to the ground temperature and to climate warming. In most cases, rock glaciers do not represent any serious hazard, except the instability of their surface and local rockfalls at the steep front. The surface movements, though moderate, can nevertheless cause damages to sensible infrastructures like cableways or buildings, if these are not designed to adapt to surface movements. The strong accelerations observed on some rock glaciers, however, induce a change of magnitude, and may threaten in some cases downslope areas. Thus, the presence of active or inactive rock glaciers with high ice content must be considered not only with regard to present conditions and dynamics, but with respect to possible evolutions due to climate change.
Auteurs, date et publication :
Auteurs Giorgio Lollino , Andrea Manconi , John Clague , Wei Shan , Marta Chiarle , P. Schoeneich , X. Bodin , T. Echelard , V. Kaufmann , A. Kellerer-Pirklbauer , J. -M. Krysiecki , G. K. Lieb
Date : 2025
Volume : 1
Pages : 223-227