
Julien Renaud- Research Assistant at Grenoble Alpes University
Julien Renaud
- Research Assistant at Grenoble Alpes University
About
105
Publications
38,238
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
3,619
Citations
Introduction
I'm a research assistant at Laboratoire d'Ecologie Alpine.
My job spans differents aspects of geomatics. It goes from spatial data administration, acquisition, analysis to cartographic production. I also assist researchers in building and administrating relational databases. I'm also developing the data entry interfaces wether online (websites, API) or for field survey purposes (Electronic field notebooks).
Current institution
Publications
Publications (105)
We present a decade-long research initiative of biodiversity genomics, which aimed at sequencing all vascular plant species occurring in the biodiversity hotspot of the European Alps, along with related lineages occurring in other mountain ranges and the arctic region. We detail the sampling and sequencing strategies, an online database for genome...
Three‐quarters of the planet's land surface has been altered by humans, with consequences for animal ecology, movements and related ecosystem functioning. Species often occupy wide geographical ranges with contrasting human disturbance and environmental conditions, yet, limited data availability across species' ranges has constrained our understand...
Recent climate and land use change, and pollution have led to concerning alterations in biodiversity and ecosystem functions, jeopardizing nature’s contributions to people. Mountainous regions are not immune to these threats, experiencing the impacts of global warming, increased recreational activities, and changes in agricultural practices. Levera...
Due to the central role of landscape connectivity in many ecological processes, evaluating and accounting for it has gained attention in both theoretical and applied ecological sciences. To address this challenge, researchers often use generic species to simplify multi‐species connectivity assessments. Yet, this approach tends to oversimplify movem...
The global network of protected areas has rapidly expanded in the past decade and is expected to cover at least 30% of land and sea by 2030 to halt biodiversity erosion. Yet, the distribution of protected areas is highly heterogeneous on Earth and the social-environmental preconditions enabling or hindering protected area establishment remain poorl...
1. Due to the central role of landscape connectivity in many ecological processes, evaluating and accounting for it has gained attention in both theoretical and applied ecological sciences. To address this challenge, researchers often used generic species to simplify multi-species connectivity assessments. Yet, this approach tends to oversimplify m...
Motivation
Accurate estimates of species distributions are crucial for biogeography, spatial conservation, and for assessing the impacts of human activities on species. However, existing approaches to estimate species distributions have typically neglected the influence of land use intensity, potentially overlooking the negative impacts of high‐int...
Arthropods play a vital role in ecosystems; yet, their distributions remain poorly understood, particularly in mountainous regions.
This study delves into the modelling of the distribution of 31 foliar arthropod genera in the French Alps, using a comprehensive approach encompassing multi‐trophic sampling, community DNA metabarcoding and random fore...
Land use intensification favours particular trophic groups which can induce architectural changes in food webs. These changes can impact ecosystem functions, services, stability and resilience. However, the imprint of land management intensity on food‐web architecture has rarely been characterized across large spatial extent and various land uses....
Our knowledge of the factors influencing the distribution of soil organisms is limited to specific taxonomic
groups. Consequently, our understanding of the drivers shaping the entire soil multitrophic network is constrained.
To address this gap, we conducted an extensive soil biodiversity monitoring program in the French Alps,
using environmental D...
Climate is a main driver of species distributions, but all species are not equally affected by climate change, and their differential responses to similar climatic constraints might dramatically affect the local species composition. In the context of climate warming, a better knowledge of the ability of dispersal-limited and habitat-specialist spec...
Background and aims:
Studying trait variability and restricted gene flow between populations species can reveal species dynamics. Peripheral populations commonly exhibit lower genetic diversity and trait variability due to isolation and ecological marginality, unlike central populations experiencing gene flow and optimal conditions. This study foc...
Our knowledge of the factors influencing the distribution of soil organisms is limited to specific taxonomic groups. Consequently, our understanding of the drivers shaping the entire soil food web is constrained. To address this gap, we conducted an extensive soil biodiversity monitoring program in the French Alps, using environmental DNA to obtain...
Motivation
Although dispersal ability is one of the key features determining the spatial dynamics of plant populations and the structure of plant communities, it is also one of the traits for which we still lack data for most species. We compiled a comprehensive dataset of seed dispersal distance classes and predominant dispersal modes for most Eur...
Aim
Understanding how combinations of ecological traits at the community‐level vary with environmental conditions is crucial to anticipate and respond to the biodiversity crisis. While this topic is popular, most attempts to analyse and predict multiple traits in space and time ignore the inherent correlations between these traits. In doing so, the...
The re‐assembly of plant communities during climate warming depends on several concurrent processes. Here, we present a novel framework that integrates spatially explicit sampling, plant trait information and a warming experiment to quantify shifts in these assembly processes. By accounting for spatial distance between individuals, our framework al...
Land use intensification favours particular trophic groups which can induce architectural changes in food-webs. These changes can deeply impact ecosystem functioning, stability and robustness to extinctions. However, the imprint of land management intensity on food-web architecture has rarely been characterised across large spatial extent and vario...
Biological invasions are one of the greatest threats to biodiversity and ecosystem functioning. However, the constraints imposed by the invaders on native organisms and their associated response, remain poorly understood. Native species can survive invasion through multiple resistance strategies (avoidance, tolerance, or escape), but the relative i...
Aim
Although soil biodiversity is extremely rich and spatially variable, both in terms of species and trophic groups, we still know little about its main drivers. Here, we contrast four long‐standing hypotheses to explain the spatial variation of soil multi‐trophic diversity: energy, physiological tolerance, habitat heterogeneity and resource heter...
Aim
To determine the interplay between climate and land use changes in driving population dynamics in a butterfly species, Coenonympha hero, at the southern limit of its distribution.
Location
French Jura massif and Europe.
Methods
We analysed patterns of genetic diversity distribution at 817 loci in 136 butterflies from 31 sites using NGS to inf...
The evolution of migration routes in birds remains poorly understood as changes in migration strategies are rarely observed on contemporary timescales. The Richard’s Pipit, a migratory songbird breeding in Siberian grasslands and wintering in Southeast Asia, has only recently become a regular autumn and winter visitor to western Europe. Here, we ex...
Plant-pollinator interactions are key components of ecosystem functioning and are therefore increasingly studied. Of all the approaches used to estimate these interactions, the capture of pollinators along transects is a widely used and recognized method. However, specific choices of sampling design can strongly influence observations of insect vis...
Plant–soil interactions can be major driving forces of community responses to environmental changes in terrestrial ecosystems. These interactions can leave signals in aboveground plant functional traits and belowground microbial activities and these signals can manifest in observed covariations. However, we know little about how these plant–soil li...
In the current biodiversity crisis, one of the crucial questions is how quickly plant communities can acclimate to climate warming and longer growing seasons to buffer the impairment of community functioning. Answering this question is pivotal especially for mountain grasslands that experience harsh conditions but provide essential ecosystem servic...
Priorities to protect nature in Europe
There is consensus among conservation scientists that protected areas should be expanded to safeguard biodiversity and ecosystem services, but it is often difficult to prioritize areas for protection. Considering factors that motivate conservation across Europe, an analysis by O'Connor et al. includes the valu...
Protected areas are the flagship management tools to secure biodiversity from anthropogenic impacts. However, the extent to which adjacent areas with distinct protection levels host different species numbers and compositions remains uncertain. Here, using reef fishes, European alpine plants, and North American birds, we show that the composition of...
By altering gene expression and creating paralogs, genomic amplifications represent a key component of short‐term adaptive processes. In insects, the use of insecticides can select gene amplifications causing an increased expression of detoxification enzymes, supporting the usefulness of these DNA markers for monitoring the dynamics of resistance a...
Although the importance of edaphic factors and habitat structure for plant growth and survival is known, both are often neglected in favor of climatic drivers when investigating the spatial patterns of plant species and diversity. Yet, especially in mountain ecosystems with complex topography, missing edaphic and habitat components may be detriment...
Whether variation of winter migration distance among individuals within a population has consequences on their reproductive performance has rarely been assessed. Using individual global location sensor-tracking, we determined variation in migration distance, and its breeding consequences, in a Svalbard colony of the little auk Alle alle , a high-Ar...
Identifying species that are both geographically restricted and functionally distinct, i.e. supporting rare traits and functions, is of prime importance given their risk of extinction and their potential contribution to ecosystem functioning. We use global species distributions and functional traits for birds and mammals to identify the ecologicall...
While soil ecosystems undergo important modifications due to global change, the effect of soil properties on plant distributions is still poorly understood. Plant growth is not only controlled by soil physico‐chemistry but also by microbial activities through the decomposition of organic matter and the recycling of nutrients essential for plants. A...
Environmental features impacting the spread of invasive species after introduction can be assessed using population genetic structure as a quantitative estimation of effective dispersal at the landscape scale. However, in the case of an ongoing biological invasion, deciphering whether genetic structure represents landscape connectivity or founder e...
Intraspecific trait variability (ITV) is an important component of functional ecology studies. While functional biogeography requires us to understand broad-scale patterns of trait distribution, ITV remains inadequately studied. Due to isolation of ranges, habitat fragmentation and sharp topoclimatic gradients over short distances, temperate mounta...
Aim: Global variation in animal colouration has inspired ecogeographical rules that suggest common patterns of recurrent adaptations to climate. However, little attention has been paid to the relative influence of the different climatic conditions encountered by species during their annual life cycle. We explored this question by testing whether br...
By altering gene expression and offering a hold for selection by creating paralogs, genomic duplications represent a key component of short-term adaptive processes. In insects, the use of insecticides can select gene duplications causing an increased expression of detoxification enzymes, supporting their usefulness for monitoring the dynamics of re...
Effective conservation of biodiversity should build on a strong basis of taxonomic and spatial distribution knowledge. The Carpathian Mountains, an iconic centre of biodiversity in temperate Europe, harbour a remarkable number of endemic vas-cular plants. Current knowledge on their taxonomic status, spatial distribution and genetic diversity is, ho...
Effective conservation of biodiversity should build on a strong basis of taxonomic and spatial distribution knowledge. The Carpathian Mountains, an iconic centre of biodiversity in temperate Europe, harbour a remarkable number of endemic vas-cular plants. Current knowledge on their taxonomic status, spatial distribution and genetic diversity is, ho...
Local adaptation patterns have been found in many plants and animals, highlighting the genetic heterogeneity of species along their range of distribution. In the next decades, global warming is predicted to induce a change in the selective pressures that drive this adaptive variation, forcing a reshuffling of the underlying adaptive allele distribu...
Local adaptation patterns have been found in many plants and animals, highlighting the genetic heterogeneity of species along their range of distribution. In the next decades, global warming must induce a change in the selective pressures that drive this adaptive variation, forcing a reshuffling of the underlying adaptive allele distributions. For...
Invasive species can encounter environments different from their source populations, which may trigger rapid adaptive changes after introduction (niche shift hypothesis). To test this hypothesis, we investigated whether postintroduction evolution is corre‐ lated with contrasting environmental conditions between the European invasive and source rang...
Aim
Seasonal bird migration is one of the most fascinating global ecological phenomena. Yet, the biogeographic scenarios and climatic drivers that led single species or entire lineages to evolve seasonal migration between disjunct breeding and wintering ranges remain unclear. Based on distribution and phylogenetic data for all birds worldwide, we e...
The Western Paleartic species of Neocrepidodera Heikertinger (Coleoptera: Chrysomelidae: Galerucinae: Alticini) mostly occur in medium and high elevation ecosystems particularly sensitive to climate change.
Here, using ensemble projections from state‐of‐the‐art habitat suitability modelling techniques, we investigated how climate change and associa...
While there is a clear demand for scenarios that provide alternative states in biodiversity with respect to future emissions, a thorough analysis and communication of the associated uncertainties is still missing. Here, we modelled the global distribution of ~11,500 amphibian, bird and mammal species and project their climatic suitability into the...
Modelling cultural ecosystem services is an enduring challenge, raising issues about the integration and spatialization of immaterial values and benefits, and their contingency on local preferences. Building on the Recreation Opportunity Spectrum framework, we present a novel methodology for assessing the recreation service using GPS tracks downloa...
Outdoor activities not accounted for in the Grelou model.
(PDF)
ROS implementation details.
(PDF)
Proximity of natural landscapes and waterscapes: quantitative details.
(PDF)
Number of GPS tracks or recreation sites per activities.
(PDF)
Intermediate factor maps.
(PDF)
Maps of spatial extent of opportunity factors.
(PDF)
Site-based activities quantitative details.
(PDF)
Protection statuses used to compute the ‘Conservation factor’.
(PDF)
Description of results from the online survey.
(PDF)
Results from the online survey.
(PDF)
Itinerary-based activities quantitative details.
(PDF)
Attractiveness-weighted remoteness quantitative details.
(PDF)
Calculation of the scenic beauty factor (mountain only).
(PDF)
Overview of the online validation survey.
(PDF)
Aim
Translocation remains a controversial strategy in species conservation. Here, we utilise the unusual scenario of invasive alien species (IAS) threatened with extinction in their native range to address key challenges in deciding ‘whether’, ‘where’, and ‘when’ to implement translocation, and how best to approach conservation under seemingly cont...
Organisms have evolved a diversity of life-history strategies to cope with variation in their environment. Persistence as adults and/or seeds across recruitment events allows species to dampen the effects of environmental fluctuations. The evolution of life cycles with overlapping generations should thus permit the colonization of environments with...
Aim
When modelling the distribution of animals under current and future conditions, both their response to environmental constraints and their resources’ response to these environmental constraints need to be taken into account. Here, we develop a framework to predict the distribution of large herbivores under global change, while accounting for ch...
The European Union (EU) 2020 Biodiversity strategy aims at guaranteeing and enhancing the future supply of ecosystem services (‘ES’) in the member states. In an ex-ante assessment of plausible environmental policies, we projected the supply of 10 ES under 3 policy alternatives of land-use change (‘Nature Protection’, ‘Payment for carbon sequestrati...
Aim
We aimed to assess the relative influence of the historical and contemporary processes determining global patterns of current β‐diversity. Specifically, we quantified the relative effects of contemporary climate and historical plate tectonics on β‐diversity at different phylogenetic scales.
Location
Global.
Time Period
Contemporaneous.
Major...
Plant endemism in the European Alps is clustered into particular geographic areas. Two contrasted and non exclusive hypotheses have been suggested to explain these hotspots of endemism: (i) those areas were glacial refugia, where endemism reflects survival-recolonisation dynamics since the onset of Pleistocene glaciations, (ii) those are high eleva...
Aim:
Plants occurring on high-alpine summits are generally expected to persist due to adaptations to extreme selective forces caused by the harshest climates where angiosperm life is known to thrive. We assessed the relative effects of this strong environmental filter and of other historical and stochastic factors driving plant community structure...
Plant endemism in the European Alps is clustered into particular geographic areas. Two contrasted and non exclusive hypotheses have been suggested to explain these hotspots of endemism: (i) those areas were glacial refugia, where endemism reflects survival-recolonisation dynamics since the onset of Pleistocene glaciations, (ii) those are high eleva...
Convergent adaptive evolution of species' ecological niches-i.e., the appearance of similar niches in independent lineages-is the result of natural selection acting on niche-related species traits ("traits" hereafter) and contrasts with neutral evolution [1-4]. Although trait convergences are recognized as being of importance at the species scale,...
Tracking long-term environmental changes in the French Alps Permanent plots resurveyed every 5 years Plots located along elevational gradients covering 1000m or more Gradients capturing the ecosystem diversity of mountain landscapes Sites distributed from the Maritime Alps to Mont-Blanc
Assembly of grassland communities has long been scrutinized through the lens of functional diversity. Studies generally point to an overwhelming influence of climate on observed patterns of functional diversity, despite experimental evidence demonstrating the importance of biotic interactions. We postulate that this is because most observational st...
Despite the recognition that some species might quickly adapt to new conditions under climate change, demonstrating and predicting such a fundamental response is challenging. Morphological variations in response to climate may be caused by evolutionary changes or phenotypic plasticity, or both, but teasing apart these processes is difficult. Here w...
During the last decades, describing, analysing and understanding the phylogenetic structure of species assemblages has been a central theme in both community ecology and macro-ecology. Among the wide variety of phylogenetic structure metrics, three have been predominant in the literature: Faith's phylogenetic diversity (PDFaith), which represents t...
In analogy to the species-area relationship (SAR), one of the few laws in Ecology, the phylogenetic diversity-area relationship (PDAR) describes the tendency of phylogenetic diversity (PD) to increase with area. Although investigating PDAR has the potential to unravel the underlying processes shaping assemblages across spatial scales and to predict...
Quantifying relationships between snow cover duration and plant community properties remains an important challenge in alpine ecology. This study develops a method to estimate spatial variation in energy availability in the context of a topographically complex, high-elevation watershed, which was used to test the explanatory power of environmental...
Protected areas (PAs) are pivotal tools for biodiversity conservation on the Earth. Europe has had an extensive protection system since Natura 2000 areas were created in parallel with traditional parks and reserves. However, the extent to which this system covers not only taxonomic diversity but also other biodiversity facets, such as evolutionary...
Aim
To incorporate changes in alpine land cover (tree line shift, glacier retreat and primary succession) into species distribution model ( SDM ) predictions for a selection of 31 high‐elevation plants.
Location
Chamonix Valley, French Alps.
Methods
We fit linear mixed effects ( LME ) models to historical changes in forest and glacier cover and p...
Le projet CHAMOIS avait pour principal objectif de cartographier les milieux ouverts
d’altitude (pelouses, prairies et landes) de l'Isère à une résolution métrique. Il s'agit d'un défi
technique et scientifique car une telle entreprise n'a jamais été conduite sur des territoires de
montagne aussi vastes. Pour mener à bien cette recherche, le projet...
The role of competition for light among plants has long been recognised at local scales, but its importance for plant species distributions at larger spatial scales has generally been ignored. Tree cover modifies the local abiotic conditions below the canopy, notably by reducing light availability, and thus, also the performance of species that are...
Nowadays the use of remote sensing for vegetation mapping over large areas is becoming progressively common, with the increase of satellites providing a good trade-off between metric spatial resolution and large swath (e.g. Spot 5, RapidEye). In France, the government launched an ambitious project to map all terrestrial habitats of the national ter...
Despite considerable efforts devoted to investigate the community assembly processes driving plant invasions, few general conclusions have been drawn so far. Three main processes, generally acting as successive filters, are thought to be of prime importance. The invader has to disperse (1st filter) into a suitable environment (2nd filter) and succe...
Background
Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role pollutants play in the decline of amphibian populations remains unclear. Amongst the most common aquatic contaminants, polycyclic aromatic hydrocarbons (PAHs) have been shown to induce several adverse effects on amphibi...
Understanding decadal-scale land-cover changes has the potential to inform current conservation policies. European mountain landscapes that include numerous protected areas provide a unique opportunity to weigh the long-term influences of land-use practices and climate on forest-grassland ecotone dynamics. Aerial photographs from four dates (1948,...
Aim Phylogenetic diversity patterns are increasingly being used to better understand the role of ecological and evolutionary processes in community assembly. Here, we quantify how these patterns are influenced by scale choices in terms of spatial and environmental extent and organismic scales. LocationEuropean Alps.
Methods We applied 42 sampling...
We investigate patterns of phylogenetic diversity in relation to species diversity for European birds, mammals and amphibians, to evaluate their congruence and highlight areas of particular evolutionary history. We estimate the extent to which the European network of protected areas (PAs) network retains interesting evolutionary history areas for t...
Aim
To define biome‐scale hotspots of phylogenetic and functional mammalian biodiversity ( PD and FD , respectively) and compare them with ‘classical’ hotspots based on species richness ( SR ) alone.
Location
Global.
Methods
SR , PD and FD were computed for 782 terrestrial ecoregions using the distribution ranges of 4616 mammalian species. We use...
Cushion plants have long fascinated botanists for their ability to cope with extreme environments in most mountains and arctic regions of the world. One century ago, a first worldwide catalogue of species forming cushions was published by Hauri and Schröter (Bot Jahrb Syst Pflanzengesch Pflanzengeogr 50:618–656, 1914). Here, we defined a simplified...
Climate and land cover changes are important drivers of the plant species distributions and diversity patterns in mountainous regions. Although the need for a multifaceted view of diversity based on taxonomic, functional and phylogenetic dimensions is now commonly recognized, there are no complete risk assessments concerning their expected changes....
Despite the recognized joint impact of climate and land cover change on facets of biodiversity and their associated functions, risk assessments have primarily evaluated impacts on species ranges and richness. Here we quantify the sensitivity of the functional structure of European avian assemblages to changes in both regional climate and land cover...
Distribution of functional distinctiveness and functional vulnerability values for 846 coral reef fishes, 2,979 alpine plants, and 662 tropical trees. Functional distinctiveness, expressed as a proportion of the maximum observed value, quantifies the uniqueness of species biological traits from the rest of the pool in the ecosystem. Functional vuln...
Number of species for each statistical analysis, each scale, each dataset, and each functional vulnerability level if any.
(XLSX)
List and details of functional traits for fish, plants, and trees.
(DOC)