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In this paper we assess the relationship between the frequency of clonal traits and environmental factors in plant communities facing abiotic constraints imposed by an alpine environment. The study was conducted in the Vanoise Massif,inner part of the French Alps, at 1,620 to 2,800 m a.s.l. We sampled 169 communities that encounter a broad set of environmental constraints, and that were distributed over the entire Massif. For all species, we documented clonal traits using data available in the literature (e.g., the CLOPLA database), completed by other sources and our own measurements. Four traits that have previously been shown to be correlated with abiotic stress and disturbances were considered: duration of clonal integration, clonal production, spreading rate, and bud-bank size. Clonal characteristics of plant communities (aggregated traits) along the two main environmental gradients (altitude and duration of snow cover) were assessed. The distribution of clonal traits was significantly but weakly correlated with environmental factors. The duration of clonal integration and bud-bank size increased with altitude, and clonal production decreased. The duration of clonal integration and the size of the bud bank were also higher in snow beds. Scree communities were characterized by a high spreading rate and a large bud bank. The duration of integration was unexpectedly shorter in disturbance-prone habitats, and spatial mobility was unexpectedly higher in one of the most stressed habitats. [ABSTRACT FROM AUTHOR]

The European Birds Directive (EBD) prevents hunting during spring migration, primarily to facilitate birds' use of habitats before and during the prenuptial journey. In line with the EBD requirements, the hunting season for waterfowl in southern France was shortened by two months during February–March since the mid-1950s. However, consequences of such hunting bans for late winter habitat use have not been evaluated. We investigated a 55-years dataset from a major international wintering ground to assess whether the EBD-related changes in hunting legislation have led to increased regional teal Anas crecca numbers during late winter. Teal abundance in the Camargue during late winter increased over the last decades: the ban on hunting in February was the best predictor of teal numbers during that month, leading to a sudden 50% increase in relative abundance. In March a more gradual temporal increase since the mid-1960 was instead recorded. Whether the increase in teal during late winter resulted from locally wintering birds or those from elsewhere stopping in the Camargue cannot be discerned. Nonetheless, the increase in teal numbers supports the basis for the EBD, in that a ban on hunting during late winter is associated with a greater use of habitats during this crucial part of the annual cycle, especially in February. [ABSTRACT FROM AUTHOR]

Understanding the population dynamics of rare and endangered plant species is essential to elaborate correct management plans for their conservation. Demographic monitoring of individual species provides valuable information here. However, demographic studies are limited to species for which one can follow individuals through their life history. They are also time consuming, making it difficult to make simultaneous studies of several species with different populations in order to have a more general assessment of rare species dynamics in a given region. In this paper, we illustrate how the use of an approach based on transition frequencies allows for the simultaneous study and comparison of trends in 32 populations of six species with very different life histories and growth forms in the Mediterranean region of the South of France. The results show significant effects of spring rainfall deficit on annual population dynamics but not for perennial species that show a delayed response, and illustrate population declines due to direct human impacts on populations in the study region. Our study illustrates the alarming overall vulnerability of populations and is simple and rapid to apply in a multi-population and multi-species context. It could thus be used by conservation management staff to construct assessments of population vulnerability elsewhere. [ABSTRACT FROM AUTHOR]

In Europe, African swine fever virus (ASFV) is one of the most threatening infectious transboundary diseases of domestic pigs and wild boar. In September 2018, ASF was detected in wild boar in the South of Belgium. France, as a bordering country, is extremely concerned about the ASF situation in Belgium, and an active preparedness is ongoing in the country. One of the questions raised by this situation relates to disturbing activities that may affect wild boar movements and their possible impact on the spread of ASFV. Despite evidence of disturbance related to hunting practices, there is a paucity of information on the impact of forestry and human leisure activities. To assess this impact on wild boar movements, a systematic review was first conducted but very few useful data were obtained. For this reason, an expert elicitation was carried out by the French Agency for Food, Environmental and Occupational Health & Safety in order to deal with this knowledge gap. A total of 30 experts originating from France and adjacent neighbouring countries (Spain, Belgium and Switzerland) were elicited about the relative importance of six factors of spatial disturbance of wild boar (noise, smell, invasion of space, modification of the environment, duration and frequency of the activity). Then, for each factor of disturbance, they were asked about the impact of 16 different commercial forestry and human leisure activities. A global weighted score was estimated in order to capture the variability of a wide range of territorial conditions and the uncertainty of expert elicitation. This estimate permitted ranking all 16 activities and aggregating them in three groups according to their potential for disturbance of wild boar, using a regression tree analysis. The results of this expert elicitation provide a methodological approach that may be useful for French and other European decision makers and stakeholders involved in the crisis management of ASF. [ABSTRACT FROM AUTHOR]

The trait-based approach aims to detect functional patterns in vegetation beyond specific sites or taxa. In most cases, plant traits are assumed to be linearly related to environmental gradients such as grazing intensity. To generalize results beyond specific sites, it is important to know to which extent environment-trait relationships are non-linear. Non-linearity can be a source of inconsistency among different studies according to length and studied portion of a gradient. In this study, we test if and to what extent traits relate non-linearly to a grazing gradient using data from a grassland-matorral interface in the Mediterranean rangeland of “La Crau” (SE France). Because quantification of grazing by itinerant sheep flocks is difficult, we use a marker plant, Phillyrea angustifolia, and several independent pasture indicators to estimate grazing intensity. First, we related traits to grazing using a multivariate three-table ordination method (RLQ), which assumes linear reactions of traits. To evaluate the importance of non-linearity, we applied generalized additive models (GAMs) to our data. This revealed that a third of traits studied here showed non-linear relationships to grazing. These non-linear responses cover a large spectrum including seed mass, life form, phenology dispersal- and leaf traits. The high part of non-linear relations compromises a general assumption of linear trait-environment relationships. Future works should therefore more often consider non-linear relationships using methods with no constraints on shape of response, e.g., GAM in the analysis of functional trait studies. In this way, non-linear relationships can reveal new aspects of species and community response to global change and deepen our understanding of trait-environment relations. [ABSTRACT FROM AUTHOR]

Ranunculus communities have been identified by the European Community Directive on Conservation of Natural and Semi-Natural Habitats as a key habitat in need of protection. The ecological requirements and floristic composition of three Ranunculus communities were investigated in North-Eastern France. We also aimed to determine the relationships between environmental parameters, Ranunculus abundance and species richness. R. Fluitans communities clearly differed from the other communities by a higher evenness and species richness and by the occurrence of specific species. In contrast, R. Penicillatus and R. Peltatus communities displayed similar floristic content. Three different sub-associations were however identified within these communities. If alkalinity was determinant in isolating R. Fluitans communities from the other stretches, the ecological ranges of the three communities strongly overlapped while considering parameters linked with other resources or with physical constraints. Further, no significant correlations were highlighted between environmental parameters, Ranunculus abundance and species richness. With respect to conservation, these observations may indicate the particular difficulty in defining each Ranunculus habitat on a European scale, and identify several key points which need to be taken into account when evaluating their status. [ABSTRACT FROM AUTHOR]

In the last few decades, trampling has become a cause of major disturbance to natural areas. Trampling can occur regularly either seasonally or throughout the year, or as a single impact depending on a recreational activity or an event. This study, carried out on a coastal heathland in north Brittany (France), was based on the hypothesis that the vegetation response can differ depending on whether the trampling is repeated or due to a single event. The aim was to compare the resistance and the short-term recovery capacity of selected species in coastal heathland communities subjected to a trampling experiment, applied once or five times (with equal total number of passes from 0 to 800). The temporal distribution of the trampling did not affect the response of Erica ciliaris, whereas for Erica cinerea and Ulex gallii, trampling was slightly less damaging when applied once rather than five times. These differences could be linked to the lower resistance and the higher recovery capacity of E. ciliaris, compared with the two other species. This study also emphasized the influence of site location by comparing observations with previous studies. Plant resistance calculated here appeared to be lower than that calculated for a less stressful site. The relationship between plant traits and response to trampling was also investigated. The effects of the different times between disturbance application and observations of the short-term response of woody vegetation to experimental trampling is also discussed. [ABSTRACT FROM AUTHOR]