Auteurs, date et publication :

Auteurs Najoi El Azhari , Stéphanie Lainé , Valérie Sappin-Didier , Jérémie Beguet , Nadine Rouard , Laurent Philippot , Fabrice Martin-Laurent

Publication : Agriculture, Ecosystems and Environment

Date : 2025

Volume : 158

Pages : 72-82


Catégorie(s)

#INRAE #PRO

Résumé

Climate change and particularly increasing frequency of drought events during the vegetation period may threaten tree vitality and forest biomass productivity in many temperate regions in the future. In that context, the identification of critical environmental factors and a better understanding of their impact on forests are decisive. The water balance is recognized as one of the most important soil factors for stand productivity in temperate forests. Hence, the consequences of short or long term climate change might vary considerably spatially in function of soil type within a given forest. Our study objective was to assess the impact of contrasting soil types on the water balance and stand growth of a beech (Fagus sylvatica) forest ecosystem of similar age and management during four climatically contrasting years. The experimental forest site of Montiers presents different soils with contrasting physicochemical properties (Dystric Cambisol, Eutric Cambisol and Rendzic Leptosol) monitored to quantify water fluxes and stand biomass increment. Using data collected over the period 2012–2015, including a particularly dry year (À24% precipitations in 2015), we also quantified the impact of water shortage on stand productivity at the annual scale as a function of soil type. We evidenced important differences in soil water holding capacities (SWHC) along the studied soil sequence, ranging between 57 mm for the Rendzic Leptosol downhill over limestone and 205 mm for the Dystric Cambisol uphill over detrital sediments. The results show that the canopy intercepted the same amount of incident rainfall in the three plots and that there were no significant differences in annual soil moisture dynamics among the studied soils. We evidenced different rooting patterns depending on soil type. Under a same climate and with stand, site exposition and solar radiation equivalency, trees transpiration was the evident primary driver of the stand potential to produce aboveground biomass. Soil water holding capacity, annual trees transpiration and aboveground biomass production increased in that order: Rendzic Leptosol < Eutric Cambisol < Dystric Cambisol. During the drier year 2015, the decrease in aboveground biomass productivity was of similar amplitude on the three soil types.


Auteurs, date et publication :

Auteurs Gil Kirchen , Christophe Calvaruso , André Granier , Paul-Olivier Redon , Grégory Van der Heijden , Nathalie Bréda , Marie-Pierre Turpault

Publication : Forest Ecology and Management

Date : 2025

Volume : 390

Pages : 89-103


Catégorie(s)

#FORET Montiers #INRAE

Résumé

Chironomidae are a major group of littoral secondary producers whose spatial changes in assemblage structures are shaped by diverse variables. Using their subfossil remains, we aimed at disentangling the relative impact of environmental, topographic, littoral occupation and hydrodynamic variables on the littoral assemblages as well as identifying taxa and sites of primary importance for the b-diversity in a large lake (Lake Bourget). A redundancy analysis coupled with a variance partitioning indicated that 22% of the assemblage variability was explained by slope, carbonate concentration and littoral occupation. A non-negligible fraction of non-separable variance among these variables likely highlights the topographic constraint on anthropogenic development and environmental conditions. Taxonomic turnover overwhelmingly (93.2%) dominated the assemblage changes indicating site-specific taxonomic composition. The taxa contribution to b-diversity was positively correlated with their mean abundances. The local abundances were either positively or negatively correlated with local contribution of sites to b-diversity (LCBD) providing evidence for different contributions of taxa to b-diversity. A couple of taxa (i.e. Cricotopus spp., Microtendipes sp. and Cladotanytarsus sp.) and sites (i.e. LB57, LB31, LB2) clearly supported the major variations of b-diversity and are therefore identified as being of primary importance regarding conservation programs. Both LCBD variations and taxa spatial autocorrelations suggest that chironomid assemblages were the most variable at a spatial-scale ranging from 500 m to 1 km, characterizing the spatial successions of littoral contexts. These results illustrate the need for considering short spatial scales to reveal the extent of the benthic diversity in the littoral areas of large lakes.


Auteurs, date et publication :

Auteurs Victor Frossard , Philippe Marchand

Publication : Knowledge & Management of Aquatic Ecosystems

Date : 2025

Issue : 419

Pages : 45


Catégorie(s)

#INRAE #OLA

Résumé

While considerable insights on the ecological consequences of climate change have been gained from studies conducted on remote lakes, little has been done on lakes under direct human exposure. Ecosystem vulnerability and responses to climate warming might yet largely depend on the ecological state and thus on local anthropogenic pressures. We tested this hypothesis through a paleolimnological approach on three temperate large lakes submitted to rather similar climate warming but varying intensities of analogous local forcings (changes in nutrient inputs and fisheries management practices). Changes in the structure of the cladoceran community were considered as revealing for alterations, over the time, of the pelagic food web. Trajectories of the cladoceran communities were compared among the three study lakes (Lakes Geneva, Bourget, and Annecy) over the last 70–150 years. Generalized additive models were used to develop a hierarchical understanding of the respective roles of local stressors and climate warming in structuring cladoceran communities. The cladoceran communities were not equally affected by climate warming between lakes. In Lake Annecy, which is the most nutrient-limited, the cladoceran community was essentially controlled by local stressors, with very limited impact of climate. In contrast, the more nutrient-loaded Lakes Geneva and Bourget were more sensitive to climate warming, although the magnitude of their responses and the pathways under which climate warming affected the communities varied between the two lakes. Finally, our results demonstrated that lake vulnerability and responses to climate warming are modulated by lake trophic status but can also be altered by fisheries management practices through changes in fish predation pressure. Key words: climate change; food web; human stressors; lake; paleolimnology; time series modeling.


Auteurs, date et publication :

Auteurs Benjamin Alric , Jean-Philippe Jenny , Vincent Berthon , Fabien Arnaud , Cecile Pignol , Jean-Louis Reyss , Pierre Sabatier , Marie-Elodie Perga

Publication : Ecology

Date : 2025

Volume : 94

Issue : 12

Pages : 2767-2780


Catégorie(s)

#INRAE #OLA

Résumé

Estuaries are considered as key habitats for the early life stages of fish. However, in the face of massive destruction of many estuarine intertidal areas, management and conservation measures are needed. Fish condition indicators may be used as a proxy of habitat quality and provide valuable information for management of coastal areas. In this study, the larvae of golden mullet (Chelon auratus) and European glass eels (Anguilla anguilla) were sampled in three sites of the Gironde Estuary. Different lipid classes and fatty acids were quantified: phospholipids (globally, phosphatidylethanolamine and phosphatidylcholine), triglycerides, omega-3 (particularly docosahexaenoic and eicosapentaenoic acids), omega-6 and C18:1. These biomarkers provide information on the nutritional status of the larvae as well as on prey availability and larvae diet between sites. One site significantly differed from the others as it seemed to offer abundant and better-quality prey. The very high levels of omega-3 contained in mullet larvae suggested that this site provided a high amount of diatoms. However, the mullet larvae that colonized this site also showed physiological stress that could be explained by exposure to pollutants through their prey. This work constitutes an essential baseline for developing biomarkers to assess the quality of habitats in a global change context.


Auteurs, date et publication :

Auteurs Elorri Arevalo , Nicolas Mazzella , Henrique N. Cabral , Aurélie Moreira , Gwilherm Jan , Bertrand Villeneuve , Carl Possémé , Mario Lepage

Publication : Journal of Fish Biology

Date : 2025

Volume : 105

Issue : 1

Pages : 201-213


Catégorie(s)

#INRAE #XPO

Résumé

Aim: Our understanding of the mechanisms that maintain forest diversity under changing climate can benefit from knowledge about traits that are closely linked to fitness. We tested whether the link between traits and seed number and seed size is consistent with two hypotheses, termed the leaf economics spectrum and the plant size syndrome, or whether reproduction represents an independent dimension related to a seed size–­seed number trade-­off.


Auteurs, date et publication :

Auteurs Michal Bogdziewicz , Marie‐Claire Aravena Acuña , Robert Andrus , Davide Ascoli , Yves Bergeron , Daniel Brveiller , Thomas Boivin , Raul Bonal , Thomas Caignard , Maxime Cailleret , Rafael Calama , Sergio Donoso Calderon , J. Julio Camarero , Chia‐Hao Chang‐Yang , Jerome Chave , Francesco Chianucci , Natalie L. Cleavitt , Benoit Courbaud , Andrea Cutini , Thomas Curt

Publication : Global Ecology and Biogeography

Date : 2025

Volume : 32

Issue : 5

Pages : 683-694


Catégorie(s)

#CNRS #FORET OPTMix #INRAE

Auteurs, date et publication :

Auteurs D. Gerdeaux , E. Dufour

Publication : Knowledge and Management of Aquatic Ecosystems

Date : 2025

Issue : 416

Pages : 35


Catégorie(s)

#INRAE #OLA

Résumé

The bouquets of ecosystem services rendered by permanent hay meadows Permanent grasslands produce high-quality forage and host very diverse plant communities. They also play a key role in carbon storage. However, we still understand little about how pedoclimatic conditions and plant community management or functioning help generate ecosystem services. This study analysed 32 grasslands in Normandy, Lorraine, and Auvergne that offer different ecosystem services. Certain grasslands had high values for service indicators. However, no synergies among services were observed, which suggests that determinant factors were different. A functional traits approach showed that plant community functioning directly affected forage quality. Plant diversity was tied to agricultural management and is also likely related to grassland history and landscape structure. Carbon storage levels were related to the clay content of soils.


Auteurs, date et publication :

Auteurs E Tasset , A Morvan-Bertrand , B Amiaud , K Klumpp , R Vecrin , P Mischler , S Husse , S Lemauviel-Lavenant

Publication : Fourrages

Date : 2025

Pages : 13


Catégorie(s)

#ACBB #ACBB Theix #INRAE

Résumé

Pour étudier les impacts de l’agriculture sur l’environnement, rien de mieux que de pratiquer. Des chercheurs du Laonnois exploitent une ferme expérimentale depuis 10 ans.


Auteurs, date et publication :

Auteurs Virginie Guennec

Publication : Journal L'Union abonné

Date : 2020


Catégorie(s)

#ACBB #ACBB Mons #INRAE

Résumé

Environmental sciences depend heavily on observational data. Successful studies of ecological processes in lakes require in-situ data that cover the relevant temporal scales from milliseconds to entire seasons. Temporal and spatial coverage requirements represent a non-trivial challenge in lake sciences, which have traditionally used sampling campaigns conducted from research vessels or anchored moorings. These come with various logistical tasks and impose constraints on data coverage. An open water platform can overcome many of these limitations by providing continuous access and a wide range of analytical capabilities in direct contact with the lake environment. A consortium of five partner institutions constructed a 10 × 10 m, open-water, multipurpose platform on Lake Geneva (Switzerland/France) for a broad range of limnological research. The LéXPLORE platform, anchored since February 2019 at a position reaching 110 m depth off the lake's north-shore, provides workspace for a large number of instruments and up to 16 staff working in parallel on individual or integrated multidisciplinary projects. The safe, dry and protected floating laboratory offers direct access to the lake environment for high-sensitivity, high-throughput analyses including those which might advance sensor technology. The platform provides flexible workspace for both high-resolution measurements and investigations of larger-scale external forcing. It thus supports multidisciplinary empirical research in limnology, atmospheric sciences, and remote sensing. This article describes the platform and how it will advance aquatic sciences. The large number of projects that have already requested access to the platform demonstrate the efficacy and necessity of the LéXPLORE concept. This article is categorized under: Water and Life > Conservation, Management, and Awareness Water and Life > Methods


Auteurs, date et publication :

Auteurs Alfred Wüest , Damien Bouffard , Jean Guillard , Bastiaan W. Ibelings , Sébastien Lavanchy , Marie-Elodie Perga , Natacha Pasche

Publication : WIREs Water

Date : 2025

Volume : 8

Issue : 5

Pages : e1544


Catégorie(s)

#INRAE #OLA