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1. Contrasted Successional Trajectories in a Mediterranean Wetland Due to Geomorphic- and Human-Induced Perturbations

Author: Elodie Brisset, Frédéric Guiter, Yoann Poher, Frédéric Médail, Philippe Ponel, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), and ANR-11-LABX-0061,OTMed,Objectif Terre : Bassin Méditerranéen(2011)
Subjects: Ecology, island, [SDE]Environmental Sciences, Environmental Chemistry, ecological succession, Mediterranean, paleoecology, wetland, Ecology, Evolution, Behavior and Systematics, ecological functioning
Abstract: International audience; Wetland ecosystems in water-limited environments locally boost biotic interactions, habitat diversity, and species concentrations, but little knowledge exists on their long-term functioning and susceptibility to regime shifts that might influence conservation and reclamation actions. Here we used a historical ecology approach on a rare Mediterranean peat-bog to reconstruct ecological successions for the last 4 millennia. The reconstruction is used to explore the role of geomorphic thresholds, climate changes, and anthropogenic perturbations as drivers of the ecosystem trajectory in the frame of the projected aridification of the climate. Our findings highlight how the superimposition of pastoral disturbances to river incision, has exacerbated ecosystem sensitivity to climate changes. Considering the long-term trajectory, the disappearance of the ecosystem might occur independently of changes in the precipitation regime. Insights given by Historical Ecology have implications for our understanding of ecosystem responses to perturbations, demonstrating that long-term dynamics must be considered before engaging in strict conservation action
Published: 2022
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2. Pollinator Specific Richness and Their Interactions With Local Plant Species: 10 Years of Sampling in Mediterranean Habitats

Author: Benoît Geslin, Floriane Flacher, Frédéric Guiter, Laurence Affre, Gabriel Nève, Xavier Lair, Lise Ropars, Catherine Fernandez, David Genoud, Clémentine Mutillod, Matthieu Aubert, Lucie Schurr, Coline C. Jaworski, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Observatoire des Abeilles, Department of Zoology [Oxford], University of Oxford [Oxford], Quartier du Pujol, 66730 Sournia, France, and University of Oxford
Subjects: 0106 biological sciences, Pollination, Endangered species, Flowers, Biology, Generalist and specialist species, 010603 evolutionary biology, 01 natural sciences, 03 medical and health sciences, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Pollinator, Animals, Syrphidae, Ecosystem, Ecology, Evolution, Behavior and Systematics, biodiversity, 030304 developmental biology, 0303 health sciences, Near-threatened species, Ecology, conservation, Bees, Plants, 15. Life on land, Pollinator decline, Insect Science, [SDE]Environmental Sciences, Threatened species, France, Species richness, Bombyliidae, Apoidea, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis
Abstract: In the context of global pollinator decline, little is known about the protection status and ecology of many species. This lack of knowledge is particularly important for Mediterranean protected areas that harbor diverse pollinator communities and are subject to considerable anthropogenic pressures. Calanques National Park (85 km2), which is located near Marseille (France), is dominated by Mediterranean low-vegetation habitats, such as phrygana and scrublands. These habitats offer favorable conditions for pollinator species due to the important amount of floral resources. Within a 10-yr period, we recorded bee (Hymenoptera: Apoidea: Anthophila), hover fly (Diptera: Syrphidae), and bee fly (Diptera: Bombyliidae) species and their interactions with the local flora through 10 field campaigns. We caught 250 pollinator species, including 192 bees, 38 hover flies, and 20 bee flies, for a total of 2,770 specimens. We recorded seven threatened bees (six near threatened and one endangered). Among the bee species, 47.9% were below-ground nesting species, and 54.7% were generalist species. Analysis of the pollination network showed that generalist and specialist pollinators do not share the same floral resources. The Cistaceae plant family (Malvales: Cistaceae) acted as a central node in the plant–pollinator network, interacting with 52 different pollinator species, which shows the importance of large open flowers that could be easily visited by both short and long-tongued pollinators in Mediterranean habitats. The occurrence of pollinator species and their ecological traits should strongly contribute to reinforcing the available information to provide or ameliorate the conservation statuses determined by IUCN Red List.
Published: 2020
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3. Paleohydrological history of Lake Allos (2200 m a.s.l) since 13 500 cal a bp in the Mediterranean Alps inferred from an ostracod δ 18 O record

Author: Rosine Cartier, Laurence Vidal, Florence Sylvestre, Corinne Sonzogni, Frédéric Guiter, Elodie Brisset, Cécile Miramont, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Lund University [Lund], Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), and Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS)
Subjects: Arts and Humanities (miscellaneous), Mediterranean Alps, oxygen isotopes, ostracods, [SDE]Environmental Sciences, Earth and Planetary Sciences (miscellaneous), Paleontology, paleohydrology, Lateglacial/Holocene
Abstract: International audience; This paper presents the first Lateglacial/Holocene (the last 13 500 cal a BP) ostracod δ18O record to infer hydroclimate variability in the Southern French Alps. Cytherissa lacustris (δ18Osp) shells extracted from the sediments of Lake Allos allowed a reconstruction of δ18Olake water (δ18Olw) except for the interval 5800–2800 cal a BP. The shape of the Younger Dryas (YD) clearly differed from records documented in the northern Alps. First, δ18Olw values remained close to modern values before a marked drop ca. 12 000 cal a BP. Then, after several oscillations, δ18Olw values increased, reaching the highest value of the record ca. 6100 cal a BP during a thermal optimum for this latitude. Finally, low δ18Olw values occurred from 450 to 100 cal a BP during the Little Ice Age (LIA) following the MedievalClimate anomaly. At the beginning of the YD, δ18Olw probably reflected changes in local glacier dynamics and precipitation sources. The following decrease in δ18Olw values was associated with higher freshwater inputs during the second half of the YD. During the LIA, the low δ18O values are consistent with a higher torrential activity and lower air temperatures
Published: 2022
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4. Late-Glacial palaeotemperatures and palaeoprecipitations in the Aubrac Mountains (French Massif Central) reconstructed from multiproxy analyses (Coleoptera, chironomids and pollen)

Author: Philippe Ponel, Frédéric Guiter, Emmanuel Gandouin, Odile Peyron, Jacques-Louis de Beaulieu, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)
Subjects: Modern analogue method, Insects, Multi-proxy approach, Palaeobotany, Transfer function, MESH: Mutual climatic range method (MCR), Transfer function, Modern analogue method, Multi-proxy approach, Palaeoclimate, Insects, Palaeobotany, [SDE]Environmental Sciences, Palaeoclimate, Earth-Surface Processes, Mutual climatic range method (MCR)
Abstract: International audience; New investigations performed with a multi-proxy approach provide a robust climate reconstruction for the Late-Glacial in the Massif Central, France. The temperature reconstruction from Coleoptera is obtained from the Mutual Climatic Range Method, or “MCR” method, based on the range of climates corresponding to the area occupied today by the species identified in fossil assemblages. The Weighthed Averaging Partial Least Squared (WA-PLS) method is used to produce mean July temperature estimates from Chironomid assemblages. Climate reconstruction from pollen data is performed using an assemblage approach, the Modern Analogue Technique. During the Late-Glacial the July temperature (Tmax) reconstructed from beetles (Coleoptera) was lower than the current Tmax of 18.9 ◦C. Summer conditions were close to the present at the beginning of the Oldest Dryas (17400–14600 cal. BP), and during most of the Allerød (13900–12800 cal. BP). During the Younger Dryas(12800–11700 cal. BP) Tmax estimates ranged from 12 to 13 ◦C, much lower than today. The Tmax increased at the onset of the Holocene (11700 cal. BP), reaching values close to the modern conditions from the beginning of the period. Tmax reconstructed from chironomids shows an initial warming around 15000 cal. BP, with a Tmax rise from 7 ◦C to 11 ◦C. A maximum (13.5 ◦C) was reached around 13800 cal. BP. A second optimum of 16 ◦C occurred after 10800 cal. BP. The Late-Glacial Interstadial (LGI) is marked by temperature decreases (from 13 to 12 to 10–9 ◦C) around 13200–12900 cal. BP. A second climate minimum was reached around 12600 cal. BP, during the Younger Dryas (Tmax about 10 ◦C). The end of the Younger Dryas seems to have been warmer, with a Tmax of about 13 ◦C, just before the early Holocene climate improvement. Pollen-inferred results showed that the Late-Glacial climate at Rousti`eres was characterized by colder and drier winter and summer seasons than today, and by conditions close to the modern ones around 11700 cal. BP, at the onset of the Holocene. Climate conditions comparable to the modern ones were also evidenced at the end of the Allerød, with colder than today conditions evidenced from both Tmax and Tmin (January temperature). During the Oldest and Younger Dryas the coldest month showed a temperature of - 13 ◦C, while summers appeared more moderate (warmest month around 16 ◦C). Cold conditions were also reconstructed during the Bølling, while temperatures comparable to present-day values were reached during the Allerød. A cold oscillation occurred around 13400 cal. BP. Particularly dry conditions were reconstructed during the Oldest Dryas (17000–15800 cal. BP). From 15800 to the end of the Younger Dryas, the precipitation oscillated around 750 mm, but increased during the Allerød and the Holocene periods. These climatic trends reconstructed by the three proxies allowed identifying the temperateperiods (LGI and the Holocene) and the cold events (Younger Dryas) of the Late-Glacial period. However, difficulties due to different sampling resolutions emerged, and several discrepancies linked to the proxy or the methods used are discussed
Published: 2022
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5. Erosion of insect diversity in response to 7000 years of relative sea-level rise on a small Mediterranean island

Author: Valérie Andrieu-Ponel, Yoann Poher, Philippe Ponel, Frédéric Médail, Frédéric Guiter, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU), Institut de Recherche pour le Développement (IRD), Avignon Université (AU), and Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU)
Subjects: 0106 biological sciences, Mediterranean climate, 010504 meteorology & atmospheric sciences, Fauna, Biodiversity, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Wetland, 010603 evolutionary biology, 01 natural sciences, 14. Life underwater, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Nature and Landscape Conservation, geography, geography.geographical_feature_category, Ecology, biology, Tamarix, 15. Life on land, biology.organism_classification, 13. Climate action, [SDE]Environmental Sciences, Threatened species, Species richness
Abstract: International audience; We have investigated the potential effects of global sea-level rise on Mediterranean coastal wetlands by studying the Coleoptera and pollen fossil remains in a 7000-year sedimentary record, which we obtained from a coastal marshy area on a small Mediterranean island (Cavallo, southern Corsica). Using beetle structural diversity and plant composition as recorded prior to marine and human influences as a `past analogue', we reconstructed the impact of the Holocene relative sea-level rise on the coastal ecosystem. Our results show that beetle species richness and diversity were highest when freshwater was predominant, which was the case until about 6200 years ago. We also found that a major increase in salinity had occurred over the last 5300 years, experiencing a peak rate of increase at about 3700 years ago. These changes are clearly reflected in the fossil records of the following key taxa: halophilous beetles (Ochthebius sp., Pterostichus cursor), halophilous plants (Chenopodiaceae, Tamarix) and non-pollen palynomorphs (microforaminiferal linings). In particular, we note that the majority (60%) of wetland beetle fauna became locally extinct in response to the salinity changes, and these changes were exacerbated by the recent aggravation of human pressures on the island. The major part of this diversity loss occurred 3700 years ago, when the relative Mediterranean sea-level rose above -1.5 +/- 0.3 meters. These findings demonstrate the value of fossil beetle assemblage analysis as a diagnostic for the response of coastal wetland biodiversity to past salinity increases, and serve as a means of forecasting the effects of sea-level rise in the future. The conservation of inland freshwater bodies could ultimately prove essential to preserving freshwater insect diversity in threatened coastal environments.
Published: 2017
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6. Palaeoenvironmental change and glacier fluctuations in the high Tian Shan Mountains during the last millennium based on sediments from Lake Ala Kol, Kyrgyzstan

Author: Marine Rousseau, Pierre Sabatier, Elodie Brisset, Philippe Sorrel, Cécile Miramont, François Demory, Frédéric Guiter, Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)
Subjects: 010506 paleontology, Paleomagnetism, [SDE.MCG]Environmental Sciences/Global Changes, Central asia, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Central Asia, Precipitation, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, Little ice age, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, Plateau, Paleohydrology, Paleontology, Glacier, Proglacial lake, Rock magnetism, 13. Climate action, Clastic rock, Physical geography, Geology
Abstract: International audience; A suite of limnological proxies measured in clastic sediments of the glacier-fed Lake Ala Kol (NE Kyrgyzstan) document palaeoenvironmental change and glacier fluctuations in the central Tian Shan over the last millennium. Rock magnetic and geochemical data provide supporting evidence for three glacier expansion episodes occurring in 1200–1400 CE, 1500–1850 CE and 1900–1950 CE and glacier retreat periods during 1000–1200 CE and the intervening periods. The maximal glacier extent, as inferred from high κLF, Si/inc + coh, Ca/inc + coh and low ARM30/ARM, is recorded between 1500 and 1850 CE and corresponds to cold and wet conditions during the Little Ice Age in the high central Tian Shan. Periods of glacier waxing and waning recorded at Lake Ala Kol present a close correspondence to ice accumulation rate in the northern Tibetan Plateau, suggesting that precipitation changes are the main driver of glacier fluctuations in central Tian Shan during the last millennium, although temperature may have exerted a more complex influence on centennial timescales.
Published: 2020
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7. New insights on lake sediment DNA from the catchment: importance of taphonomic and analytical issues on the record quality

Author: Gentile Francesco Ficetola, Jérôme Poulenard, Kevin Walsh, Fernand David, Erwan Messager, Elodie Brisset, Pierre Sabatier, Anne-Lise Develle, Laurent Fouinat, Ludovic Gielly, Fabien Arnaud, Rémi Sinet, Manon Bajard, Charline Giguet-Covex, Frédéric Guiter, Pierre Taberlet, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), BioArch-Department of Archaeology, Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Department of Environmental Science and Policy [Milano], Università degli Studi di Milano = University of Milan (UNIMI), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut Català de Paleoecologia Humana i Evolució Social (IPHES), Àrea de Prehistòria, Universitat Rovira i Virgili, Universitat Rovira i Virgili, DiPEE Chambéry-Grenoble (University Grenoble Alpes and University Savoie Mont Blanc), the Zone Atelier Alpes (ZAA), the PEPS de site Grenoble and the Conseil Général of Isère (AAP on biodiversity), the Parc National des Ecrins, Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Università degli Studi di Milano [Milano] (UNIMI), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ecologie Alpine (LECA), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA), Department of Environmental Science and Policy, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU)
Subjects: 0301 basic medicine, 0106 biological sciences, Geologic Sediments, Taphonomy, Earth science, Drainage basin, lcsh:Medicine, EarthArXiv|Physical Sciences and Mathematics|Earth Sciences, EarthArXiv|Life Sciences|Ecology and Evolutionary Biology, 01 natural sciences, bepress|Life Sciences, EarthArXiv|Life Sciences, Limnology, Human Activities, Glacial period, EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Sedimentology, lcsh:Science, ComputingMilieux_MISCELLANEOUS, bepress|Life Sciences|Ecology and Evolutionary Biology|Terrestrial and Aquatic Ecology, Multidisciplinary, geography.geographical_feature_category, EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Geology, Palaeoecology, Agriculture, Plants, [SDE]Environmental Sciences, Erosion, Soil horizon, Molecular ecology, Agricultural landscapes, Environmental Monitoring, bepress|Physical Sciences and Mathematics, bepress|Physical Sciences and Mathematics|Earth Sciences|Sedimentology, [SDE.MCG]Environmental Sciences/Global Changes, 010607 zoology, bepress|Physical Sciences and Mathematics|Earth Sciences, EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Soil Science, bepress|Life Sciences|Ecology and Evolutionary Biology, 010603 evolutionary biology, Article, C2FN, 03 medical and health sciences, Humans, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, EarthArXiv|Life Sciences|Ecology and Evolutionary Biology|Terrestrial and Aquatic Ecology, geography, bepress|Physical Sciences and Mathematics|Earth Sciences|Geology, lcsh:R, Sediment, EarthArXiv|Physical Sciences and Mathematics|Earth Sciences|Geochemistry, DNA, 15. Life on land, [SDE.ES]Environmental Sciences/Environmental and Society, EarthArXiv|Physical Sciences and Mathematics, bepress|Physical Sciences and Mathematics|Earth Sciences|Soil Science, Lakes, 030104 developmental biology, Soil water, Environmental science, bepress|Physical Sciences and Mathematics|Earth Sciences|Geochemistry, lcsh:Q
Abstract: Over the last decade, an increasing number of studies have used lake sediment DNA to trace past landscape changes, agricultural activities or human presence. However, the processes responsible for lake sediment formation and sediment properties might affect DNA records via taphonomic and analytical processes. It is crucial to understand these processes to ensure reliable interpretations for “palaeo” studies. Here, we combined plant and mammal DNA metabarcoding analyses with sedimentological and geochemical analyses from three lake-catchment systems that are characterised by different erosion dynamics. The new insights derived from this approach elucidate and assess issues relating to DNA sources and transfer processes. The sources of eroded materials strongly affect the “catchment-DNA” concentration in the sediments. For instance, erosion of upper organic and organo-mineral soil horizons provides a higher amount of plant DNA in lake sediments than deep horizons, bare soils or glacial flours. Moreover, high erosion rates, along with a well-developed hydrographic network, are proposed as factors positively affecting the representation of the catchment flora. The development of open and agricultural landscapes, which favour the erosion, could thus bias the reconstructed landscape trajectory but help the record of these human activities. Regarding domestic animals, pastoral practices and animal behaviour might affect their DNA record because they control the type of source of DNA (“point” vs. “diffuse”).
Published: 2019
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8. Histoire de l’environnement et des usages anthropiques sur l’île de Cavallo (archipel des Lavezzi, Corse)

Author: Yoann Poher, Frédéric Médail, Philippe Ponel, Frédéric Guiter, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), and PONEL, Philippe
Subjects: [SDE] Environmental Sciences, Ecology, Biodiversity, Forestry, Chalcolithic, 15. Life on land, insularité, paléoécologie, remontée relative du niveau marin, île de Méditerranée, changements environnementaux, impacts humains, language.human_language, Prehistory, Geography, Sea level rise, relative sea-level rise, Mediterranean island, human impacts, insularity, palaeoecology, Environmental changes, 13. Climate action, [SDE]Environmental Sciences, language, 14. Life underwater, Environmental history, Corsican, ComputingMilieux_MISCELLANEOUS, Ecology, Evolution, Behavior and Systematics
Abstract: This study synthetizes the terrestrial environmental history of the Cavallo Island, the largest Corsican satellite island (120 ha), located in the Strait of Bonifacio. Ecosystems dynamics and terrestrial biodiversity have been deciphered for 7,000 years thanks to the paleoecological analysis of fossil pollen and beetle remains. These results underligne the profound changes in the structure and specific composition of terrestrial communities of vascular plants and insects. These changes are related to the relative sea level rise and to anthropogenic impacts. Over time, Cavallo Island represented a hunting territory for prehistoric men from the Neolithic/ Chalcolithic period, then a famous site of granite exploitation by the Romans, a refuge and a haunt for many pirates or corsairs, an “insular enclosure” facilitating the free pastures of cattle brought in “nautical transhumance” by the Bonifaciens. In the early 1970, it became an “island of billionaires” and a territory of lawlessness with a sulfurous reputation. This ultimate episode caused the most impacts on the natural environment : Ecosystems were deeply altered by an uncontrolled urbanization that has had profound consequences on terrestrial biodiversity (destruction and fragmentation of natural habitats ; biological invasions ; filling, pollution and eutrophication of wetlands)., Ce travail dresse l’histoire environnementale terrestre de l’île de Cavallo, l’île satellite corse la plus vaste (120 ha), située dans le détroit de Bonifacio. La dynamique des écosystèmes et de la biodiversité terrestre a pu être reconstituée depuis 7 000 ans grâce à l’analyse paléoécologique conjointe des pollens fossiles et des restes de coléoptères. Ces résultats montrent les profonds changements de structure et de composition spécifique des communautés terrestres de végétaux vasculaires et d’insectes. Ces modifications sont liées à la remontée relative du niveau marin et aux impacts anthropiques. Tour à tour, l’île de Cavallo a représenté un territoire de chasse pour les hommes du Néolithique/ Chalcolithique, puis un site bien connu d’exploitation de granite par les Romains, un territoire refuge et un repaire pour les nombreux pirates ou corsaires, une île-enclos facilitant les libres pâtures du bétail amené en «transhumance marine» par les Bonifaciens. Elle est devenue, au début des années 1970, une «île de milliardaires» et un territoire de non-droit à la réputation sulfureuse. Cet ultime épisode a engendré le plus d’impacts sur le milieu naturel : l’environnement a été profondément altéré par une urbanisation non contrôlée, dont les conséquences sur la biodiversité terrestre ont été profondes (destruction et fragmentation des habitats naturels ; invasions biologiques ; comblement, pollution et eutrophisation des zones humides)., Médail Frédéric, Guiter Frédéric, Poher Yoann, Ponel Philippe. Histoire de l’environnement et des usages anthropiques sur l’île de Cavallo (archipel des Lavezzi, Corse). In: Ecologia mediterranea, tome 43 n°2, 2017. Le patrimoine naturel de l'île de Cavallo (archipel des Lavezzi, Corse) : écologie, biogéographie et conservation. pp. 5-22.
Published: 2017
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9. Diatom-oxygen isotopic record from high-altitude Petit Lake (2200 m a.s.l) in the Mediterranean Alps: shedding light on a climatic pulse

Author: Frédéric Guiter, Anne Alexandre, Rosine Cartier, Corinne Sonzogni, Martine Couapel, Jean-Charles Mazur, Cécile Miramont, Christine Paillès, Florence Sylvestre, and Elodie Brisset
Subjects: Mediterranean climate, Water balance, geography, geography.geographical_feature_category, Erosion, Lake ecosystem, Drainage basin, Environmental science, Climate change, Precipitation, Physical geography, Holocene
Abstract: The 4.2 kyrs event, used as a marker of holocene stratigraphy, has been described as a rapid climate change in the northern hemisphere triggering droughts in the Mediterranean region. However, the severity and geographical extent of this event are still the subject of investigation considering the small number of palaeoclimatic records for this time period, and the presence of contrasted climatic expressions between areas. At Petit Lake (France, Mediterranean Alps, 2200 m a.s.l) a multiproxy study of Holocene lake sediments has revealed major changes in erosion processes and phytoplanktonic assemblages in the lake ecosystem around 4200 cal. BP. According to pollen analysis, deforestation is unlikely to be the main explanation of environmental changes as the watershed was covered by open vegetation for the duration of the study period. To test the implication of climate, our study presents an analysis of oxygen isotopes (δ18O) in diatoms describing hydrological modalities during the 4.2 kyrs event in the Mediterranean Alps. The highest values of δ18Odiatom occur from 4400 to 3900 cal. BP and are interpreted as an increase in water evaporation and/or a decrease in freshwater inputs to the lake system. Changes in water balance might have been associated with a change in precipitation sources towards a greater influence of precipitation coming from the Mediterranean area. These results are concomitant to an increase in erosion in the watershed and high representation of very low-dispersal pollen in the sediments suggesting the presence of intense runoff. This new isotopic record together with previously-published proxy-data, allows us to describe the 4.2 kyrs event at Petit Lake as an increase in Mediterranean climate influences in the region, amounting to a general dry period punctuated by episodes of intense runoff occurring on the catchment slopes.
Published: 2018
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10. Impacts of sea-level rise and responses of Mediterranean coastal wetland biodiversity: lessons from fossil insect assemblages

Author: Yoann, Poher, Philippe, Ponel, Frédéric, Guiter, Kazuyo, Tachikawa, Frédéric, Médail, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Leydet, Michelle, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE] Environmental Sciences, Fossil beetle, Biodiversity changes, [SDE]Environmental Sciences, Corsican back-barrier wetlands
Abstract: This conference aims to facilitate scientific exchange between early-career researchers (ECRs) from a broad range of disciplines working with sea-level change. The conference will include two days of oral and poster presentations by ECRs, invited keynote lectures, a one day field excursion to the Rhine delta and Holland coastal plain with conference dinner, and a public ‘Science and Society’ evening session. The conference is open to ECRs who have obtained or expect to obtain their Ph.D. in 2010 or later.; International audience; Coastal wetland-based archives have an exceptional scientific potential to observe past biodiversity changes and identify key thresholds for particular ecosystems facing relative sea-level rise. In this presentation, we focus on the multiproxy analyses (palaeoentomology, palynology and geochemistry) of two 14C-dated cores from Corsican back-barrier wetlands: the Grecu pond located on a low-laying island (S. Corsica) and the Cannuta marsh situated on a deltaic floodplain (N. Corsica). The respectively 7000-and 5900-year sedimentary records from the two sites show contrasted ecosystem trajectories, stemming mainly from their different geomorphological features. Regarding the Grecu pond, by comparing the beetle fauna present on the island today with fossil beetle assemblages, we find that 60% of past wetland beetle fauna became locally extinct because of the increase in salinity caused by marine intrusions. Most of this diversity loss occurred 3700 years ago, when relative sea-level reported in the region was at ~-1.5 meters. Regarding the Cannuta marsh, fluctuations of calcium and sulphur (used as tracers of Gypsum), show evolution from a brackish lagoon to a freshwater environment. This transition, marked by a diversification of wetland beetle fauna 1000 years ago, is possibly due to relative sea-level stability and floodplain progradation. It is consistent with evidences of soil erosion (inferred from titanium abundance) and of pastoral practices in the watershed. This retrospective approach provides a foreshadowing of potential future insect diversity changes along Mediterranean coastal lagoon ecosystems. We discuss the implications of these findings in terms of resilience and conservation strategies to minimise coastal wetland losses.
Published: 2018

11. Response of two Mediterranean coastal wetlands (Corsica, France) to Holocene relative sea-level rise and land-use changes revealed by fossil Coleoptera records

Author: Yoann, Poher, Philippe, Ponel, Frédéric, Médail, Kazuyo, Tachikawa, Frédéric, Guiter, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), and Leydet, Michelle
Subjects: [SDE] Environmental Sciences, Sea-level rise, Biodiversity changes, [SDE]Environmental Sciences, Corsica, Lagoon ecosystems, Fossil Coleoptera
Abstract: International audience; Coastal wetland-based archives have an exceptional scientific potential to observe past biodiversity changes and identify key thresholds for particular ecosystems facing relative sea-level rise (RSLR). In this presentation, we focus on the fossil Coleoptera analysis-supplemented by pollen and geochemical data-of two 14C-dated cores from Corsican back-barrier wetlands: the Grecu pond located on a low-laying island (S. Corsica) and the Cannuta marsh situated on a deltaic floodplain (N. Corsica). The respectively 7000-and 5900-year sedimentary records from the two sites show contrasted ecosystem trajectories, stemming mainly from their different geomorphological features. Regarding the Grecu pond, by comparing the beetle fauna present on the island today with fossil beetle assemblages, we find that 60% of past wetland beetle fauna became locally extinct because of the increase in salinity caused by marine intrusions. Most of this diversity loss occurred 3700 years ago, when relative sea-level reported in the region was at ~-1.5 meters. These local extinctions have been exacerbated by the aggravation of human pressures over the last decades, with the artificial reduction of the wetland surface area. Regarding the Cannuta marsh, fluctuations of calcium and sulphur (used as tracers of Gypsum), show evolution from a brackish lagoon to a freshwater environment. This transition, marked by a diversification of wetland beetle fauna 1000 years ago, is possibly due to relative sea-level stability and floodplain progradation. It is consistent with evidences of soil erosion (inferred from titanium abundance) and of pastoral practices in the watershed. We demonstrate the efficacy of fossil beetles for reconstructing the environmental changes in coastal lagoon ecosystems, their resilience, and their response to the Holocene RSLR in the western Mediterranea. This retrospective approach also provides a foreshadowing of potential future insect diversity changes along Mediterranean coastal lagoon ecosystems.
Published: 2018

12. Multiproxy analyses of Lake Allos reveal synchronicity and divergence in geosystem dynamics during the Lateglacial/Holocene in the Alps

Author: Kazuyo Tachikawa, Frédéric Guiter, Hélène Bruneton, Cécile Miramont, Edward J. Anthony, Florence Sylvestre, Elodie Brisset, Christine Paillès, Rosine Cartier, Edouard Bard, Collège de France - Chaire Evolution du climat et de l'océan, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Chaire Evolution du climat et de l'océan, and Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU)
Subjects: 010506 paleontology, Archeology, Watershed, 010504 meteorology & atmospheric sciences, Alpine lakes, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Forcing (mathematics), 01 natural sciences, Intra-Holocene boundaries, C2FN, Palaeolimnology, Ecosystem, Holocene stratigraphy, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Global and Planetary Change, Multiproxy analysis, Lake ecosystem, Palaeoecology, Geology, 15. Life on land, 13. Climate action, Paleoecology, Period (geology), Sedimentary rock, Physical geography, European Alps
Abstract: International audience; Palaeoenvironmental reconstructions of ecosystem responses to external forcing are generally limited by the difficulty of understanding the geosystem as a whole, because of the complex interactions between ecological compartments. Therefore, identifying which geosystem compartments or proxies co-vary is a prerequisite in unravelling the propagation of disturbances (e.g. climatic or anthropogenic) from one compartment to another. A multiproxy study of a continuous 13,500-year sedimentary profile cored in Lake Allos (European Alps, 2200 m a.s.l) was carried out on the basis of high-resolution sedimentological, geochemical, and botanical analyses, as well as determination of aquatic biotic proxies (diatoms, ostracods). These multiproxy datasets are rare at these high altitudes. Major changes occurred in the course of the palaeoenvironmental history of this alpine watershed at 12,000, 8600, 7200 and 3000 cal. BP. During the Holocene, two main transitions were recorded in all the ecological compartments (8600 and 3000 cal. BP), but the period 4500-3000 cal. BP stands out because of major changes that concerned only the lacustrine ecosystem. The frequent switches in lake level might correspond to the 4.2 ka climatic event. Proximity of this alpine lake to climatically-sensitive thresholds (ice-cover, thermal stratification, hydrological balance) may have amplified climatic signals in the lake ecosystem. This study illustrates the difficulties inherent to the use of common intra-Holocene stratigraphical limits, given that ecological compartments are likely to have different responses to forcing factors depending on the characteristics of the watershed and its capacity to accommodate disturbances. (C) 2018 Elsevier Ltd. All rights reserved.
Published: 2018
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13. Lateglacial-Holocene abrupt vegetation changes at Lago Trifoglietti in Calabria, Southern Italy: The setting of ecosystems in a refugial zone

Author: Giovanni Zanchetta, Liliana Bernardo, Sabine Wulf, Jacques-Louis de Beaulieu, Frédéric Guiter, Odile Peyron, Elisabetta Brugiapaglia, Damien Rius, Sébastien Joannin, Agnès Stock, Michel Magny, Julien Didier, Institut méditerranéen de biodiversité et d'écologie marine et continentale ( IMBE ), Université d'Avignon et des Pays de Vaucluse ( UAPV ) -Aix Marseille Université ( AMU ) -Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique ( CNRS ), Dipartimento de Scienze Animali, Vegetali e dell' Ambiente, Università del Molise, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Dipartimiento di Scienze della Terra, Università di Pisa, Laboratoire de chrono-écologie ( LCE ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, University of Pisa - Università di Pisa, Università degli Studi del Molise = University of Molise (UNIMOL), Laboratoire Chrono-environnement (UMR 6249) (LCE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Archeology, 010504 meteorology & atmospheric sciences, Evolution, [SDE.MCG]Environmental Sciences/Global Changes, 01 natural sciences, Lago Trifoglietti, [ SDE ] Environmental Sciences, Behavior and Systematics, Ice age, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Glacial period, Younger Dryas, Stadial, Glacial refuges, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Global and Planetary Change, Archeology (arts and humanities), Ecology, Temperate forest, Calabrian Mountains, Lake sediments, LGI-early Holocene, Pollen record, Preboreal oscillation, Tephrochronology, Geology, 15. Life on land, [ SDE.MCG ] Environmental Sciences/Global Changes, Deciduous, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, [ SDU ] Sciences of the Universe [physics]
Abstract: International audience; Retrospective science such as palaeoecology deeply depends on the preservation of archives in sensitive places. As an example, mountains of medium altitude from Mediterranean peninsulas have long been identified by biogeographers as refuges zones allowing the survival of European temperate taxa during the ice ages, but archives to validate this hypothesis are scarce, especially in Southern Italy. Here we present a new sequence from Lago Trifoglietti (1048 m a.s.l.) in the Calabrian Mountains, which covers the Late Glacial Interstadial (LGI, corresponding to the Bolling€-Allerod€ period in northern-central Europe) and the transition to the Holocene. The independent chronology based on seven radiocarbon dates is supported by the evidence of three tephra layers already identified in other regional sequences. During the LGI, besides the high diversity of non arboreal pollen grains, a great number of pollens of temperate forest trees are present or abundant (mostly deciduous oaks and fir). These assemblages suggest that the site was above but not far from the upper limit of diversified woodland stands. They confirm a local survival during the last glacial. The Younger Dryas is not marked by major changes, and oak percentages are even higher, suggesting a resilient expansion at lower altitude. Surprisingly the site remains above the timberline until an aridity crisis centered at 11,100 cal 14 C yr PB, which is correlated with the Pre-boreal Oscillation (PBO). This event is immediately followed by the local settlement of a dense fir and beech forest around the lake. A comparison with other Italian key sequences aims at explaining the climate forcing factors that governed this original vegetation dynamic. Further investigations using additional proxies are needed for a more robust climate reconstruction. (O. Peyron), l.bernardo@unical.it (L. Bernardo), Julien.Didier@ univ-fcomte.fr (J. Didier), agnes.stock@univ-fcomte.fr (A. Stock), Damien.Rius@ univ-fcomte.fr (D. Rius), Michel.Magny@univ-fcomte.fr (M. Magny).
Published: 2017
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14. Reconstructing the landscape evolution and the human occupation of the Lower Sagone River (Western Corsica, France) from the Bronze Age to the Medieval period

Author: Matteo Vacchi, Frédéric Guiter, Claude Vella, Philippe Dussouillez, Doriane Delanghe, Yannick Crest, Daniel A. Contreras, Daniel Istria, Andrés Currás, Matthieu Ghilardi, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire d'Archéologie Médiévale et Moderne en Méditerranée (LA3M), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Fondation Maison des sciences de l'homme (FMSH), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université de Perpignan Via Domitia (UPVD), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD), Centre National de la Recherche Scientifique (France), Currás, Andrés, and Currás, Andrés [0000-0002-1828-7455]
Subjects: Palynology, 010506 paleontology, Archeology, geography, geography.geographical_feature_category, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDE.MCG]Environmental Sciences/Global Changes, Drainage basin, Vegetation, 15. Life on land, 010502 geochemistry & geophysics, 01 natural sciences, Archaeology, [SDE.ES]Environmental Sciences/Environmental and Society, Alluvial plain, law.invention, Bronze Age, law, Sedimentary rock, Radiocarbon dating, Chronostratigraphy, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology, 0105 earth and related environmental sciences
Abstract: This paper aims to reconstruct the landscape evolution together with the vegetation history of the lower Sagone Valley, Western Corsica, which was occupied from the Bronze Age to the Medieval Period. Adopting a geoarchaeological approach, the combination of sedimentological, palynological, and geophysical data enables the reconstruction of various stages in the landscape evolution of the Lower Sagone River over the last 4000 years, together with the history of human occupation. The methods consist of a palaeoenvironmental study of 9 boreholes drilled in the modern deltaic plain, at a maximum distance of 500 m from the present-day shoreline. The laboratory analyses included mollusk identification and measurements of the grain-size distribution (by wet sieving). A series of 21 radiocarbon dates on charcoal, plant remains, wood fragments, and marine mollusk samples formed the basis for a chronostratigraphy. In order to reconstruct the vegetation history of the catchment, with particular attention to anthropogenic activity, pollen analysis was conducted on clay samples from the deepest borehole, and they revealed a semi-open forest during the Bronze Age and Late Iron Age with extensive pastoral activity and limited cereal cultivation. Electric Resistivity Tomography (ERT) of 3 profiles across the alluvial plain was conducted in order to reveal the geometry of the sedimentary bodies. The salient features are the presence of a freshwater lake during the Mid- to Late Bronze Age (from 1500 to 1100 cal. BCE), its transformation into an open marine bay from ca. 1100 until 500 cal. BCE, and the formation of a confined lagoon from 500 cal. BCE to 200 cal. CE.
Published: 2017
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15. The overlooked human influence in historic and prehistoric floods in the European Alps

Author: Frédéric Guiter, Cécile Miramont, Rosine Cartier, Emmanuel Malet, Pierre Sabatier, Edward J. Anthony, Tiané Troussier, Elodie Brisset, Yoann Poher, Fabien Arnaud, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), and Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU)
Subjects: Hydrology, 010506 paleontology, 010504 meteorology & atmospheric sciences, Flood myth, Reforestation, Fluvial, Climate change, Geology, 15. Life on land, 01 natural sciences, Natural (archaeology), Forest restoration, C2FN, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Soil retrogression and degradation, Physical geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Holocene, 0105 earth and related environmental sciences
Abstract: International audience; Understanding the role of climate and humans in generating mountain slope instability is crucial because such instability influences downstream fluvial activity and is a major threat to societies. Here, we use the sedimentary archive of Lake Allos (southeastern France), a mountain lake in the European Alps, to characterize mountain flood deposits and vegetation dynamics over the past 7000 yr. Our results support the interpretation of a critical threshold in catchment sensitivity to erosion at 1700 calibrated (cal.) yr B.P. (A.D. 250) probably resulting from long-term, uninterrupted impacts of human activity. The frequency and severity of floods increased dramatically after this date. These results demonstrate that underestimation of human impacts over the Holocene may pose a challenge to a clear understanding of past climate changes because paleoflood records are highly likely to have been affected by geomorphic thresholds. Natural reforestation since the end of the 19th century does not appear to be sufficient to induce a flood regime comparable to that which occurred prior to 1700 cal. yr B.P. This poses the question as to whether forest restoration in high-altitude environments is liable to foster a return to a low-erosion regime over the next decades, or whether the overall severity of soil degradation has been such as to preclude a return to previous conditions.
Published: 2017
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16. Novel insights from coleopteran and pollen evidence into the Lateglacial/Holocene transition in Aubrac, French Massif Central

Author: Valérie Andrieu-Ponel, Nathalie Van der Putten, Christine Paillès, Frédéric Guiter, Philippe Ponel, Patrick Rioual, Emmanuel Gandouin, Michelle Leydet, Morteza Djamali, Jacques-Louis de Beaulieu, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Institute of Geology and Geophysics, Chinese Academy of Sciences, Faculty of Science, Lund University, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lund University [Lund], and Earth and Climate
Subjects: 010506 paleontology, 010504 meteorology & atmospheric sciences, Oldest Dryas, Lateglacial, Palaeoenvironments, Older Dryas, Oceanography, medicine.disease_cause, 01 natural sciences, Pollen, medicine, Stadial, Younger Dryas, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, Plateau, geography.geographical_feature_category, Ecology, Paleontology, Massif central, Vegetation, 15. Life on land, Coleoptera, 13. Climate action, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology
Abstract: International audience; The aim of this study is to describe the environmental and climate changes that occurred in the mountains of Aubrac at the transition between the Lateglacial and the Holocene, from a comparative analysis of fossil Coleoptera and pollen, and a series of 23 C-14 dates. The changes affecting the ecological categories of Coleoptera lead to a division of the sequence into 5 beetle assemblage zones (BAZ): the lowermost BAZ A is characterized by extremely poor assemblages (periglacial environment); BAZ B (Oldest Dryas and Lateglacial Interstadial) is marked by regular occurrences of taxa associated with open environments, aquatic taxa associated with running and highly oxygenated water, and cold adapted taxa with relatively low numbers; BAZ C (Younger Dryas) corresponds to two important events: a particular abundance of cold adapted taxa and a marked decrease of running water taxa, beetles associated with herbaceous vegetation and open environments are also well represented; BAZ D (Early Holocene) corresponds to the total disappearance of cold adapted taxa; the transition BAZ C/BAZ D is marked also by a dramatic peak of running water taxa; the uppermost BAZ E (Early/Mid Holocene) is marked by a total absence of running water taxa which are replaced by standing water or taxa tolerant of a range of water conditions, a particular abundance of wetland taxa, and taxa associated with herbaceous vegetation and open environments. Beetle and pollen data suggest that the harsh climatic conditions prevailing in the Aubrac mountains did not allow warm dependent fauna and trees to establish during the Lateglacial Interstadial, at least in the Roustieres region, and that wide open landscapes occupied the plateau at that time. The Older Dryas, a cold spell previously recorded at La Taphanel (Cantal), is not visible in the Roustieres record, probably because of the higher altitude at Roustieres, whereas the Younger Dryas is strongly expressed. During the Holocene, concordant beetles and pollen data enable to reconstruct the rapid recolonization of the plateau by mesophilous trees (Ulmus, Quercus), suggesting the possible presence of refugia to the southern slopes of the Aubrac plateau. Insect/pollen comparisons provide evidence for hydrological changes in the former lake of Roustieres and suggest that lacustrine water level changes often used as indicator of precipitation regime changes should be taken with caution. (C) 2016 Elsevier B.V. All rights reserved.
Published: 2016
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17. Environmental and climate reconstruction of the late-glacial-Holocene transition from a lake sediment sequence in Aubrac, French Massif Central: Chironomid and diatom evidence

Author: Patrick Rioual, Stephen J. Brooks, D. Belkacem, Philippe Ponel, Christine Paillès, Michelle Leydet, N. Van der Putten, Morteza Djamali, J.-L. de Beaulieu, Harry John Betteley Birks, J.N. Haas, Emmanuel Gandouin, Valérie Andrieu-Ponel, Frédéric Guiter, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institute of Geology, Chinese Academy of Sciences [Beijing] (CAS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Department of Life Sciences, Natural History Museum, Department of Biology and Bjerknes Centre for Climate Research, Environmental Change Research Centre, University College London, University of Innsbruck, Institute of Botany, Lund University, Faculty of Science, Institute of Geology and Geophysics [Beijing] (IGG), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Bjerknes Centre for Climate Research (BCCR), Department of Biological Sciences [Bergen] (BIO / UiB), University of Bergen (UiB)-University of Bergen (UiB), University College of London [London] (UCL), Institute of Botany [Innsbruck], Universität Innsbruck [Innsbruck], Lund University [Lund], Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Petrology, and Earth and Climate
Subjects: Subfossil insects, 010506 paleontology, Peat, 010504 meteorology & atmospheric sciences, Oldest Dryas, [SDE.MCG]Environmental Sciences/Global Changes, Climate change, Western Europe, Oceanography, 01 natural sciences, Paleontology, Palaeolimnology, SDG 14 - Life Below Water, Glacial period, Younger Dryas, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, biology, Past aquatic ecosystem, Massif, 15. Life on land, biology.organism_classification, Corynocera ambigua, Diatom, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Temperature reconstruction, Physical geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology
Abstract: International audience; The analysis of fossil chironomid and diatom assemblages from a sedimentary record from Les Roustieres peat bog (Massif Central, France, 1196 m asl) allows the reconstruction of past environmental and climate changes during the late-glacial and early Holocene. Chironomid assemblages showed that the infilling of the palaeolake had commenced during the Oldest Dryas (GS-2b) as suggested by the rapid decrease in chironomid species associated with the cold and deep zone of lakes and by their replacement by littoral and eutrophic taxa. Quantitative July temperature reconstructions, based on the chironomid data, suggest that mean July air temperature (Tjul) ranged between 6 degrees C and 11 degrees C at the termination of the Oldest Dryas period (GS-2b). Climate began to warm at the start of the Bolling period (GI-1e), between 15,000 and 14,800 cal yr BP, with a rise in Tjul of about 4 degrees C. This climate warming is contemporaneous with lake eutrophication as suggested by diatoms and chironomids. Maximum temperatures of 13-14 degrees C were reached around 13,600 cal yr BP during the Allered period (GI-1c-GI-1a). The Younger Dryas period (GS-1) is marked by a return to cold conditions with Tjul of about 10 degrees C during a first phase, then 13 degrees C in its terminal part. A probable increase in the duration of the ice-cover may have favoured arctic and alpine diatom species. The early-Holocene climate improvement is marked by a rise in Tjul of about 3 degrees C. (C) 2016 Elsevier B.V. All rights reserved.
Published: 2016
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18. Coprophilous Coleoptera vs fungal spores, examples from Iran and from the Alps

Author: Philippe Ponel, Valérie Andrieu-Ponel, Monika Badura, De Beaulieu Jacques-Louis, Mona Court-Picon, Morteza Djamali, Frédéric Guiter, Hamid Lahijani, Michelle Leydet, Marjan Mashkour, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Faculty of Civil and Environmental Engineering Gdańsk University of Technology Gdańsk Poland, Institut Royal des Sciences Naturelles de Belgique (IRSNB), Iranian National Institute for Oceanography and Atmospheric Sciences (INIOAS), Archéozoologie, archéobotanique : sociétés, pratiques et environnements (AASPE), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016

19. A hundred year record of industrial and urban development in French Alps combining Hg accumulation rates and isotope composition in sediment archives from Lake Luitel

Author: Pierre Sabatier, Frédéric Guiter, Anne-Lise Develle, Carole Desplanque, David Amouroux, Caiyan Feng, Jean Louis Reyss, Fabien Arnaud, Laurent Charlet, Julien Barre, Stéphane Guédron, Institute F.-A. Forel, University of Geneva, Versoix, Switzerland, Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Office National des Forêts, 9 quai Créqui, 38000 Grenoble, France, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Océan et Interfaces (OCEANIS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux (IPREM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: Delta, mercury, 010504 meteorology & atmospheric sciences, chemistry.chemical_element, Fractionation, 010501 environmental sciences, 01 natural sciences, C2FN, Isotopes, Geochemistry and Petrology, 11. Sustainability, Industry, isotopes, 0105 earth and related environmental sciences, Hydrology, geography, Radionuclide, geography.geographical_feature_category, industry, Isotope, Terrigenous sediment, Urban area, Geology, Mercury, Mass-independent fractionation, Mercury (element), lake sediment, Lake sediment, chemistry, 13. Climate action, Environmental chemistry, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Water well, urban area
Abstract: International audience; This study reconstructs the history of multiple industrial and urban mercury (Hg) emissions recorded in the sediment archive of Lake Luitel (France) from AD similar to 1860 to AD 2011. For this purpose, we provide a well constrained short-lived radionuclides continuous age-depth relationship of the sediment sequence (mean accumulation rate of 5.18 +/- 0.28 mm.yr(-1)) with Hg accumulation rates (Hg AR), Hg isotopic composition and extensive historical data. Hg AR were stable around 45 mu g.m(-2).y(-1) from 1860 to WWI and rose to reach their maximum at the end of WWII (250 mu g m(-2) y(-1)) followed by a gradual decreased to reach about 90 mu g m(-2) y(-1) in the current period. Normalization to a terrigenous Hg proxy highlighted the dominance of atmospheric Hg inputs to the lake. The combination of Hg AR with isotopic signatures through the use of binary mixing (Delta Hg-199 vs 1/Hg AR) models and isotopic plots (and comparison to literature data) allowed us to identify the main industrial and urban historical inputs. The major outcome of this study is that the Hg mass independent fractionation (MIF) signature did not enable the identification of particular anthropogenic sources but reflected an integrated pool of industrial and urban emissions which tend to shift to less negative MIF values (mean: -0.15 +/- 0.04%) during their period of maximum emissions. Temporal MIF and Hg AR variations depict the rising Hg emissions from the industrial revolution (1860-1910) to the modern industrial and urban development period (1950-1980). Mass dependent fractionation (MDF) signatures enabled the identification of major contributors in relation to their relative intensities lying between two endmember pools: (i) the combustion activities (smelters, cement factories and urban heating) with more negative delta Hg-202 values, and (ii) the chemical and electrometallurgical activities (electrochemistry, chlor-alkali) with higher delta Hg-202 values. Unconformities of MIF and MDF signatures were observed during WWI, WWII and interwar period, and were attributed to drastic and rapid changes in regional industrial activities. Finally, recent laws regarding Hg emissions (1998-2011) prove their efficiency as Hg AR decreased with a return to more negative MIF and MDF signatures such as during the industrial revolution period. Our study highlights that the combination of Hg isotopic data with Hg AR in sediment archives is a useful tool for reconstructing the history of anthropogenic Hg emissions, and has the potential to identifiy their relative contributions. (C) 2016 Elsevier B.V. All rights reserved.
Published: 2016
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20. Nouvelles contributions à l’histoire tardiglaciaire et holocène de la végétation en Algérie : analyses polliniques de deux profils sédimentaires du complexe humide d’El-Kala

Author: Mohamed Benslama, Jérémy Migliore, Morteza Djamali, Maurice Reille, Jacques-Louis de Beaulieu, Frédéric Guiter, and Valérie Andrieu-Ponel
Subjects: Geography, General Immunology and Microbiology, North africa, Forestry, General Medicine, General Agricultural and Biological Sciences, Vegetation dynamics, General Biochemistry, Genetics and Molecular Biology
Abstract: Resume Deux sequences polliniques provenant des marais littoraux d’El-Kala ont ete etudiees en vue de retracer l’histoire de la vegetation regionale. Les assemblages polliniques etayes par huit datations 14 C ont revele, dans le marais de Bourdim une histoire recente dominee localement par une aulnaie-saulaie ; l’abondance d’ Erica arborea indique que la vegetation regionale est constituee par une suberaie tres degradee. La sequence de Garaat El-Ouez presente deux periodes distinctes : les assemblages superieurs sont comparables a ceux de Bourdim ; par contre, ceux de la base sont domines par Pinus , des Poaceae et diverses herbacees heliophiles, avec presence de Cedrus . Ils temoignent d’une vegetation forestiere ouverte attribuee par trois datations a la fin de la derniere glaciation et demontrent l’existence de refuges regionaux de Cedrus sous un climat relativement clement.
Published: 2010
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21. 5000 years of lacustrine ecosystem changes from Lake Petit (Southern Alps, 2200m a.s.l.): Regime shift and resilience of algal communities

Author: Cécile Miramont, Florence Ruaudel, Edward J. Anthony, Rosine Cartier, Florence Sylvestre, Elodie Brisset, Frédéric Guiter, Christine Paillès, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
Subjects: Archeology, BP event, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Pediastrum, catchment–lake interaction, reference conditions, diatoms, catchment-lake interaction, Ecosystem, Regime shift, Holocene, Earth-Surface Processes, Total organic carbon, Global and Planetary Change, Ecology, biology, Aquatic ecosystem, Paleontology, alpine lake, 15. Life on land, biology.organism_classification, reference, Diatom, Productivity (ecology), 4200 cal. BP event, 4200 cal, Environmental science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, conditions
Abstract: International audience; Sediments from Lake Petit (2200m a.s.l., Southern Alps) are particularly relevant for analysis of coupled landscape palaeoecology and palaeolimnology. Diatom assemblages, organic matter composition of sediments (total nitrogen and organic carbon) and Pediastrum boryanum concentrations were obtained from a 144-cm-long core, enabling the reconstruction of the aquatic ecosystem over nearly the last 5000 cal. BP. From 4800 to 4300 cal. BP, Lake Petit was a stable diatom-productive water body dominated by alkaliphilous diatoms (Staurosirella pinnata). During this period, nutrients and cations were supplied by the chemical weathering of podzols that developed under conifer woodlands. This overall stability was suddenly interrupted at 4200 cal. BP by a major detrital pulse that was probably climate linked (4200 cal. BP event) and that triggered a drop in diatom productivity and diversity. From 4100 to 2400 cal. BP, diatom productivity progressively decreased, whereas Pediastrum developed. Diatom assemblages were more diversified (predominance of Pseudostaurosira robusta, P. brevistriata and P. pseudoconstruens) and reflected a regime of continuous erosion, whereas slopes were colonised by grazed grasslands. Finally, from 2400 cal. BP to the present day, diatom assemblages reveal a slight acidification and nutrient enrichment of waters concomitant with increasing human pressure in the catchment. These results demonstrate the close links between ecosystems and the ready propagation of disturbances throughout watersheds that might lead to abrupt regime shifts in such alpine environments.
Published: 2015
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22. Lateglacial/Holocene environmental changes in the Mediterranean Alps inferred from lacustrine sediments

Author: Emmanuel Malet, Cécile Miramont, Edward J. Anthony, Frédéric Guiter, Elodie Brisset, Jacques-Louis de Beaulieu, Fabien Arnaud, Marie Revel, Claire Delhon, Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institut Universitaire de France, Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Gestion des ressources naturelles , environnements et sociétés (GReNES), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, and Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Archeology, cirque glacier, Lateglacial, [SDE.MCG]Environmental Sciences/Global Changes, Holocene climatic optimum, Rock glacier, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Paleontology, Deglaciation, Younger Dryas, Glacial period, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, Gyttja, Global and Planetary Change, geography, geography.geographical_feature_category, pollen stratigraphy, Mediterranean Alps, Geology, Glacier, 14C ages, 15. Life on land, Cirque glacier, Lake sediment, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, [SDE]Environmental Sciences
Abstract: International audience; This study investigates sediment cores from the Mediterranean alpine lakes located in upvalley cirques upper than 1700 metres a.s.l. using sedimentological, palynological and geomorphological studies, in order to document environmental changes following the last phase of glacier retreat. These results are considered in the framework of the deglaciation characterized from 16 sediment cores from high-altitude lakes and mires including 104 14C ages and geomorphological studies of the Mediterranean Alps. Considering each sediment core proxy as an independent observation, i.e., comparisons between 14C ages and palynostratigraphy, between 14C ages and lithostratigraphy, between palynostratigraphy and lithostratigraphy, these data are aimed at contributing to a better understanding of the timing of postglacial environmental changes. The 14C ages combined with pollen biostratigraphy indicate that the deglaciation of cirque catchments is dated between 14,500 and 13,000 cal. BP, i.e., during the Lateglacial Interstadial (Greenland Interstadial-1e). The sixteen lacustrine and mire sediment records are systematically characterized by three units from bottom to top: organic-poor blue clay, beige to light-brown silty clay and organic rich dark brown gyttja lithotype. During the Younger Dryas, lakes located below 2300 m a.s.l. were ice-free and their pollen record indicates steppe conditions. The sedimentary facies also informs on the timing of glacial-dominated processes. The onset of organic-rich gyttja is dated at 11,000 cal. BP suggesting the last influence of cirque glaciers in these lakes at the beginning of the Holocene. The timing of the onset of this organic rich unit differs in sites (±2000 years) probably due to an altitudinal and exposure gradient of the glacial cirques. The presence of gyttja from 11,000 cal. BP to Present indicates biogenic infilling lake for all the Holocene. Even though the literature have indicated rock glacier advances occurred during the Holocene (Subboreal and LIA) in the south of the Alps, no significant sedimentological patterns related to glacier fluctuations are recorded in Lake Vens. The glacier fluctuations in the Mediterranean Alps are concomitant with those dated in the non-Mediterranean Alps, thus suggesting a main common climate forcing. However, the increase in terrigenous sediment inputs since 1800 cal. BP is mainly due to human activities.
Published: 2015
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23. About the presence of Eemian peats in the Geneva basin and its implications: a reply to comments by Preusser et al

Author: Gérard Nicoud, Jean-Pierre Hebrard, Anne Triganon, Philippe Ponel, Frédéric Guiter, Valérie Andrieu-Ponel, and J.-L. de Beaulieu
Subjects: Archeology, Global and Planetary Change, Eemian, Geology, Physical geography, Structural basin, Archaeology, Ecology, Evolution, Behavior and Systematics
Published: 2006
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24. Lateglacial palaeoenvironments and palaeoclimates from Conty and Houdancourt, northern France, reconstructed from Beetle remains

Author: Nicole Limondin-Lozouet, Chantal Leroyer, Jean-François Pastre, Russell Coope, Pierre Antoine, André-Valentin Munaut, Frédéric Guiter, Philippe Ponel, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Royal Holloway [University of London] (RHUL), Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Ministère de la Culture et de la Communication (MCC), Centre National de Préhistoire (CNP), Université Catholique de Louvain = Catholic University of Louvain (UCL), and Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Archeology, Global and Planetary Change, geography, geography.geographical_feature_category, Floodplain, Fauna, Geology, Vegetation, Older Dryas, 010502 geochemistry & geophysics, medicine.disease_cause, 01 natural sciences, [SHS]Humanities and Social Sciences, Allerød oscillation, Paleontology, Pollen, [SDE]Environmental Sciences, Geochronology, medicine, Sedimentology, ComputingMilieux_MISCELLANEOUS, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences
Abstract: Two Lateglacial insect sequences are described (a) from Conty, in the Selle valley and (b) from Houdancourt in the Oise valley, both in northern France. These investigations are part of a multidisciplinary investigation involving archaeology, sedimentology, geomorphology, geochronology and palaeontology (pollen, macroscopic plant remains, vertebrates, molluscs and insect fossils). The sequences of insect assemblages date from the latter part of the Bolling to the end of the Allerod periods. Environmental analysis of these faunas shows that rivers with riffles and pools meandered across flood plains. The river was extensively fringed with reedy vegetation. The only trees growing close to the river were of Salix and/or Populus . All the insect assemblages indicate that the thermal climates during the Bolling and Allerod periods were similar to one another and during both periods were very nearly as warm as that of the present day. No insect fossils were recovered from the sediments attributed to the Older Dryas interval though other evidence from these sites suggests that this event was decidedly colder than those immediately preceding and succeeding it. Comparisons are made between Lateglacial climatic patterns in northern France with those elsewhere in Europe.
Published: 2005
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25. Vegetation dynamics in north-western Mediterranean regions: Instability of the Mediterranean bioclimate

Author: Valérie Andrieu-Ponel, Jacques-Louis de Beaulieu, Yannick Miras, and Frédéric Guiter
Subjects: Mediterranean climate, Palynology, Geography, Orbital forcing, Ecology, Sclerophyll, Interglacial, Macrofossil, Plant Science, Evergreen, Ecology, Evolution, Behavior and Systematics, Holocene
Abstract: Pollen and plant macrofossil records from a selection of sites in Spain, France and Italy are used to explore the origin and the development of the Mediterranean vegetation. The role of evergreen and summergreen taxa is discussed. The expansion of sclerophyllous trees during the Pleistocene interglacials is well correlated with the orbital forcing. During the Holocene, the large number of data illustrates latitudinal and longitudinal differences in vegetation dynamics. Multidisciplinary studies identify short terms climatic fluctuations. The debate is still open between those who attribute an increase of sclerophyllous forests during the late Holocene to a trend toward aridity and those who consider this dynamic as human-induced.
Published: 2005
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26. First evidence of 'in situ' Eemian sediments on the high plateau of Evian (Northern Alps, France): implications for the chronology of the Last Glaciation

Author: Jean-Pierre Hebrard, Gérard Nicoud, Frédéric Guibal, Simon Brewer, Jacques-Louis de Beaulieu, Valérie Andrieu-Ponel, Frédéric Guiter, Philippe Ponel, Anne Triganon, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Laboratoire d'Hydrogéologie d'Avignon (LHA), Avignon Université (AU), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, Archeology, 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Context (language use), Evian, 01 natural sciences, Eemian sediments, Deglaciation, Glacial period, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, Geomorphology, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, Global and Planetary Change, geography, Eemian, geography.geographical_feature_category, Plateau, Macrofossil, Geology, Glacier, Last Glacial Maximum, 15. Life on land, last glaciation, Northern Alps, France, Physical geography
Abstract: International audience; A 2 m profile of organic sediments, interbedded between two tills, was taken from the Evian high plateau at Hameau de Maravant, 860 m a.s.l. (Haute-Savoie, Western Alps, France). Pollen, plant macrofossils and insect remains were used to reconstruct the local palaeoenvironment, which consisted of a moss and Carex mire, surrounded by a dense Abies and Picea mixed forest. Pollen and macrofossil data indicate that this peat layer was deposited at the end of the Eemian interglacial. The lower till should therefore be assigned to the penultimate glaciation and the upper till to the maximum extent of the Rhône glacier during the Würm. A comparison of the results with previous studies carried out in the Geneva area and other alpine valleys has yielded a detailed reconstruction of the past fluctuations of the Rhône glacier: 1. a first Early/Lower Würmian advance, reaching the region around Lyon; 2. a subsequent retreat of ice; 3. a second moderate readvance, restricted to the surroundings of Geneva, followed by a final deglaciation. A continuous lacustrine sequence has been obtained from the nearby Roseire peat-bog (890 m a.s.l). Pollen and radiometric results show the establishment of a former palaeolake during the Upper Pleniglacial, probably before ca. 22 450±850 cal years BP, thus implying that the high plateau was ice-free from that time. These new data appear to suggest that the maximal extension of the Rhône glacier occurred prior to the Last Glacial Maximum (OIS 2) and, according to a well-documented geomorphological context, probably during the Lower Würmian Pleniglacial.
Published: 2005
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27. The last climatic cycles in Western Europe: a comparison between long continuous lacustrine sequences from France and other terrestrial records

Author: Valérie Andrieu-Ponel, Frédéric Guiter, Claude Goeury, Rachid Cheddadi, Jacques-Louis de Beaulieu, Maurice Reille, Philippe Ponel, Thierry Keller, and Marianne Calvez
Subjects: Ecological succession, Vegetation, medicine.disease_cause, Oceanography, Ice core, Western europe, Pollen, Interglacial, medicine, Stadial, Glacial period, Physical geography, Geology, Earth-Surface Processes
Abstract: During the last two decades, numerous studies applied to various continental deposits have highly improved the knowledge of environmental changes in Western Europe during the last climatic cycles. Here we review a set of available data, and try to correlate and compare the three long lacustrine sequences from France (La Grande Pile, Les Echets and Le Velay) with other west European discontinuous limnic deposits, fluvial systems and lœss accumulations. Limnic sequences provide the best records of the last Interglacial and Early Glacial (ca. 125–75 kyr) allowing a clear picture of environmental changes during this interval. Nevertheless, there are divergent interpretations on the timing and climate regime of the last Interglacial. During the last Glacial, in the North Atlantic deep-sea cores and Greenland ice cores, short-term abrupt climatic fluctuations (Bond events, Dansgaard–Oeschger events) which are poorly or partly reflected on the continent have been recognised. The classical subdivision in a Lower (ca. 75–55 kyr) (very cold), Middle (ca. 55–29 kyr) (cold) and Upper Pleniglacial (ca. 29–15 kyr) (very cold) is confirmed both by limnic and terrestrial sequences. In the Rhine valley, north-eastern France, Belgium and the Netherlands, subcontinuous lœss accumulation, river systems and associated periglacial features provide quantitative climate reconstructions that are compared with those obtained from limnic sequences. Interstadial events may be correlated with the major warm oscillations of the GRIP core. During the Upper Pleniglacial, no clear vegetation changes are apparent from lacustrine pollen sequences, whereas thick lœss accumulations have registered a succession of climatic changes. The timing of the Lateglacial warming is now well documented from rare annually laminated lake sediments.
Published: 2003
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28. A historical ecology of the Ecrins (Southern French Alps): Archaeology and palaeoecology of the Mesolithic to the Medieval period

Author: Suzi Richer, Florence Mocci, R. Sinet, Frédéric Guiter, J.-L. de Beaulieu, Stephan Tzortzis, Kevin Walsh, Brigitte Talon, Mona Court-Picon, Dept of Archaeology, University of York [York, UK], Institut royal des Sciences naturelles de Belgique - IRSNB (BELGIUM), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Centre Camille Jullian - Histoire et archéologie de la Méditerranée et de l'Afrique du Nord de la protohistoire à la fin de l'Antiquité (CCJ), Aix Marseille Université (AMU)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), ECCOREV - ARCHIPEL-Ecrins « ARCHéologie, Impact anthropique et PaléoEcoLogie dans le massif des Ecrins », Conséquences des dynamiques de peuplement humain sur le paysage, depuis l’étage montagnard jusqu’à l’étage alpin (coord. B. Talon, IMEP), du GDR 'JurAlp' « Dynamique holocène de l’environnement dans le Jura et les Alpes:du climat à l’homme » 2006-2009 (Sections 31, 32 et 20 du CNRS) ( dir. M. Magny, M. Desmet et F. Mocci), Programme FRECHALP : La haute vallée de FReissinières : Empreinte humaine et CHangements des paysages d’un espace ALPin depuis 10 000 ans (Hautes Alpes, Parc national des Ecrins), Projet Appel Ouvert Conseil Régional PACA-CNRS-ECCOREV (dir. F. Mocci), ECCOREV, Institut Royal des Sciences Naturelles de Belgique (IRSNB), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Bronze Age, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Iron Age, Context (language use), Roman, Neolithic, Mountain, palynology, Mesolithic, Holocene, pedo- and archaeo-anthracology, Earth-Surface Processes, Palynology, Ecology, archaeology, Chalcolithic, 15. Life on land, landscape, Alpine, Archaeology, 13. Climate action, (Post)Medieval, holocene, Historical ecology, Geology, human–environment, pastoralism
Abstract: International audience; This paper elucidates the nature of human–environment interactions in a mountainous landscape (the southern zone of the Ecrins, French Alps) from the Mesolithic through to the Post-Medieval Period. We present an integrated programme of palynology, pedo- and archaeo-anthracology, and archaeology. These data permit the development of a historical ecology that allows us to differentiate between climatic and anthropogenic influences on vegetation, and the development of anthropogenic landscapes in an Alpine region. This study is of profound relevance for the broader understanding of human–environment interactions in ecologically sensitive environments both within the Alpine arc, but also beyond this region.We identify and explain evidence for possible human landscape management practices in a high altitude landscape. Palynology defines the broad floral context and evolution of the environment through the Holocene. Palynology also permits an assessment of human activities and practices (arable agriculture, pastoralism and haymaking). The combination of these data with anthracological and archaeological evidence permits a nuanced assessment of human interaction with the landscape. We consider phases of anthropological–ecological succession across the range of altitudes, from valley-bottom to the alpine zones in the Ecrins National Park.Four important stages of landscape use and change have been inferred from our evidence: the Mesolithic, the Chalcolithic/Bronze Age, Iron Age and Roman, and (Post)Medieval. During the Mesolithic (c. 8000–4500 BC), a major event is the expansion of fir in the montane stage. At higher altitudes, people exploit the ecotone, defined by the forest edge (or tree-line): an ideal zone for hunting. The Neolithic sees low-altitude clearances, but a continuation of hunting and low levels of human impact on high-altitude vegetation. The Chalcolithic/Bronze Age (2400–1000 BC) sees complex interplay of climatic changes, and the appearance of direct human intervention in the high altitude landscape as part of a new transhumant system. Although the Roman Period is characterised by phases of climatic amelioration after the deterioration of the Iron Age, the increase in human activity that is usually seen in low-lying areas is not reflected in the sub-alpine and alpine altitudes. The Medieval Period, including the Little Ice Age, witnesses a steady increase in human use of these landscapes, with forest manipulation and clearance becoming the defining characteristics of these areas. Despite the supposed inclement nature of the Little Ice Age, human activity achieves its zenith, and the combination people and climate produces the most open and managed landscape of the Holocene.
Published: 2014
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29. Données nouvelles sur la chronologie de la déglaciation dans la vallée du Haut-Verdon (lac d’Allos, Alpes françaises du sud)

Author: Eric Chaumillon, Edward J. Anthony, Elodie Brisset, Yoann Poher, Frédéric Guibal, Fabien Arnaud, Rosine Cartier, Frédéric Guiter, Claire Delhon, Cécile Miramont, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Ecosystèmes continentaux et risques environnementaux (ECCOREV), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés - UMR 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Gestion des ressources naturelles , environnements et sociétés (GReNES), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS)
Subjects: lac, Southern French Alps, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Lateglacial, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Geology, Tardiglaciaire, deglaciation, Archaeology, moraine, 13. Climate action, [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy, Deglaciation, Physical geography, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, lake, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Alpes françaises du Sud, Earth-Surface Processes, Chronology, déglaciation
Abstract: International audience; This study presents new 14C AMS ages obtained from the sedimentary sequence of Lake Allos (elevation: 2,230 m, Verdon valley, Southern Alps, France). These ages provide new evidence on the last deglaciation over the Southern Alps, enabling us to revise the chronological framework previously established. Sedimentation in the lake began between 12,300 and 13,500 cal. yr BP (2 sigma interval). The two glacial stages identified in a cirque downstream of Lake Allos (at 1,900 m a.s.l.) and on the glacial threshold (at 2,300 m a.s.l.) are hence older. Our results are in good agreement with previous conclusions based on palynological evidence from high-elevations peat bogs and lakes that suggested an earlier deglaciation, at the onset of the Lateglacial.; Cet article présente les datations 14C AMS obtenues dans la séquence sédimentaire du lac d’Allos (alt. 2 230 m, vallée du Verdon, Alpes du Sud, France). Ces données contribuent à la connaissance de la chronologie de la déglaciation à l’échelle des Alpes du Sud et permettent de revoir le cadre chronologique proposé antérieurement sur ce site. La sédimentation lacustre démarre entre 12 300 et 13 500 ans cal. BP (2 sigmas). Les deux stades glaciaires identifiés en aval du lac à 1 900 m et sur le verrou glaciaire à 2 300 m sont par conséquent plus anciens. Nous rejoignons ici les conclusions des travaux antérieurs sur les tourbières et lacs d’altitude qui, sur la base des données polliniques, suggéraient une déglaciation très précoce remontant au début du Tardiglaciaire.
Published: 2013
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30. Overview of Last Deglaciation sedimentological, palynostratigraphical and 14C chronologies in mountain lake sediments: Towards improved knowledge of the MIS2/MIS1 transition in the Mediterranean Alps

Author: Frédéric Guiter, Elodie Brisset, Cécile Miramont, Bourles, D. L., Regis Braucher, Edward Anthony, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire de Recherche en Chimie Marine des Organometalliques (RCMO), Université de Toulon (UTLN), Brisset, Elodie, Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDV.EE]Life Sciences [q-bio]/Ecology, environment, [SDV.EE] Life Sciences [q-bio]/Ecology, environment, [SHS.ARCHEO] Humanities and Social Sciences/Archaeology and Prehistory, [SDU.STU.GM] Sciences of the Universe [physics]/Earth Sciences/Geomorphology, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2013

31. Non-reversible geosystem destabilisation at 4200 cal. BP: Sedimentological, geochemical and botanical markers of soil erosion recorded in a Mediterranean alpine lake

Author: Jérôme Poulenard, Edouard Bard, Claire Delhon, Jean-Dominique Meunier, Edward J. Anthony, Kazuyo Tachikawa, Frédéric Guiter, Cécile Miramont, Elodie Brisset, Franck Sumera, Fabien Arnaud, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Chaire Evolution du climat et de l'océan, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Centre Camille Jullian - Histoire et archéologie de la Méditerranée et de l'Afrique du Nord de la protohistoire à la fin de l'Antiquité (CCJ), Aix Marseille Université (AMU)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Collège de France - Chaire Evolution du climat et de l'océan, Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)
Subjects: Mediterranean climate, 010506 paleontology, Archeology, human pressure, 010504 meteorology & atmospheric sciences, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Erosion des sols, tipping point, 01 natural sciences, Stage (stratigraphy), Forest cover, impact anthropique, Destabilisation, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, Environmental history, Evènement de 4200 cal. BP, point de bascule, 0105 earth and related environmental sciences, Earth-Surface Processes, 4.2 ka event, Global and Planetary Change, soil erosion, Ecology, Mediterranean Alps, Paleontology, 15. Life on land, Tipping point (climatology), Alpes Méditerranéennes, 13. Climate action, Soil water, Human pressure, Physical geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, Geology, XRF core scanner
Abstract: International audience; A 144-cm-long core was obtained in Lake Petit (2200 m a.s.l., Mediterranean French Alps) in order to reconstruct past interactions between humans, the environment and the climate over the last five millennia using a multidisciplinary approach involving sedimentological, geochemical and botanical analyses. We show a complex pattern of environmental transformation. From 4800 to 4200 cal. BP, podzol-type soils progressively developed under forest cover. This stable situation was interrupted by a major detrital pulse at 4200 cal. BP that we consider as a tipping point in the environmental history. At this point, pedogenetic processes drastically regressed, leading to the development of moderately weathered soils. More frequent detrital inputs are recorded since 3000 cal. BP (AD 1050) as the human impact significantly increased in the catchment area. We conclude that destabilisation of the environment was triggered by climate and exacerbated by human activities to a stage beyond resilience.
Published: 2013
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32. POLLEN RECORDS, LATE PLEISTOCENE | Middle and Late Pleistocene in Southern Europe

Author: Frédéric Guiter, Valérie Andrieu-Ponel, P.C. Tzedakis, and J.-L. de Beaulieu
Subjects: Paleontology, Pleistocene, Stratigraphy, Pollen, Temperate climate, Ice age, medicine, Physical geography, Glacial period, Vegetation, Vegetation dynamics, medicine.disease_cause, Geology
Abstract: Most of the Pleistocene reference pollen sequences have been described in northern Europe (Eem, Holstein, Cromer?). Nevertheless southern Europe provides numerous long pollen records that contributed to the renewal of the Pleistocene stratigraphy. After a short review of the main pollen sites from southern Europe, this article summarizes the general trends in vegetation dynamics since the beginning of the Ice Age. The authors discuss southern Europe's role in providing refuge for temperate plants during cold episodes and the climate forcing governing vegetation cycles.
Published: 2013
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33. Approche multidisciplinaire d’une séquence lacustre holocène dans les alpes du sud au Lac Petit (Mercantour, alt. 2 200 m, France) : histoire d’un géosystème dégradé

Author: Edward J. Anthony, Jean-Robert Disnar, Cécile Miramont, Jérôme Poulenard, Bruno Wilhelm, Jean-Dominique Meunier, Elodie Brisset, Fabien Arnaud, Claire Delhon, Christine Paillès, Frédéric Guiter, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, human impact, 010504 meteorology & atmospheric sciences, sédiments lacustres, 01 natural sciences, Sequence (geology), Multidisciplinary approach, évènement de 4 200 cal. BP, végétation, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes, 4.2 ka event, French Southern Alps, soil erosion, sédiment lacustre, lacustrine sediment, érosion des sols, Sediment, Geology, 15. Life on land, [SDE.ES]Environmental Sciences/Environmental and Society, anthropisation, Alpes du Sud, 13. Climate action, pollen, Physical geography, Holocène
Abstract: L’analyse multiproxies à haute résolution d’une séquence sédimentaire prélevée dans le Lac Petit (alt. 2 200 m, vallon des Millefonts, Mercantour, France) a permis d’étudier les interactions climat-environnement-Homme à l’Holocène récent en contexte de haute montagne dans les Alpes du Sud. Grâce aux analyses lithostratigraphiques, géochimiques et palynologiques, trois grandes phases ont pu être reconstituées : (1) une période de stabilité relative de l’écosystème de 4 750 à 4 350 cal. BP, caractérisée par une sédimentation lacustre dominante et des sols développés sur les versants, (2) de 4 350 à 1 550 cal. BP, une augmentation des apports érosifs contemporaine d’une dégradation des sols superficiels et du couvert forestier, (3) une phase de déstabilisation intense et définitive des versants depuis 1 550 cal. BP. Le climat a certainement joué un rôle dans la dynamique du bassin-versant, mais l’Homme, dont l’impact reste discret jusqu’à 1 550 cal. BP, pourrait être un facteur majeur de perturbation des écosystèmes du vallon des Millefonts pendant le Subatlantique. Enfin, la récurrence d’apports terrigènes pourrait témoigner d’évènements orageux de forte intensité dont les conséquences érosives ont pu être amplifiées localement par l’augmentation de la pression agro-pastorale et des activités minières. High resolution multiproxy analyses, including sedimentological, geochemical and palynological investigations, were carried out on a 144-cm-long sediment profile from Lake Petit (2 200 m a.s.l., Vallon des Millefonts, Mercantour, in the French Southern Alps). This allowed us to reconstruct complex interactions between climate, environment and human during the Late Holocene. We identify three phases: (1) a first phase (4 750 to 4 350 cal. BP) characterized by a dominant lake sedimentation and developed soils on slopes, (2) a second period (4 350 to 1 550 cal. BP) marked by an abrupt switch in sediment source and an input of organic allochthonous matter linked with soil erosion and a more open landscape, (3) a final phase (since 1 550 cal. BP) of intense destabilization of slopes. Even if climate could have triggered such drastic changes, discreet but continuous human impact until 1 550 cal. BP might be the main factor of degradation of slopes and ecosystems in the valley. The record of abundant terrigenous input also suggests that high-intensity rainfall events might have occurred, while agro-pastoralism and local mining activities continuously weakened slopes.
Published: 2012
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34. 1400 years of extreme precipitation patterns over the Mediterranean French Alps and possible forcing mechanisms

Author: Edouard Bard, Jean-Jacques Delannoy, Pierre Sabatier, Eric Chaumillon, Jean-Louis Reyss, Kazuyo Tachikawa, Bruno Wilhelm, Frédéric Guiter, Jean-Robert Disnar, Elodie Brisset, Fabien Arnaud, Christian Crouzet, Emmanuel Malet, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés - UMR 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Chaire Evolution du climat et de l'océan, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Océan et Interfaces (OCEANIS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Collège de France - Chaire Evolution du climat et de l'océan, LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Mediterranean climate, 010506 paleontology, 010504 meteorology & atmospheric sciences, Atmospheric circulation, [SDE.MCG]Environmental Sciences/Global Changes, Solar activity, Drainage basin, Forcing (mathematics), 01 natural sciences, Arts and Humanities (miscellaneous), Flood intensity, Precipitation, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, Flood myth, Paleoflood, 13. Climate action, North Atlantic oscillation, Climatology, Erosion, General Earth and Planetary Sciences, Last millennium, North Atlantic Oscillation, Geology
Abstract: Investigation of Lake Allos sediments revealed ~ 160 graded layers, interpreted as flood deposits, over the last 1400 yr. Comparisons with records of historic floods support the interpretation of flood deposits and suggest that most recorded flood events are the result of intense meso-scale precipitation events. As there is no evidence for any major changes in erosion processes in the catchment since the Medieval Warm Period (MWP), we interpret the Allos record in terms of repeated intense precipitation events over the last millennium, with a low flood frequency during the MWP and more frequent and more intense events during the Little Ice Age. This interpretation is consistent with the pattern of increasingly humid conditions in the northwestern Mediterranean region. This long-term trend is superimposed on high frequency oscillations that correlate with solar activity and autumnal North Atlantic Oscillation (NAO). Finally, a comparison of flood records across the northwestern Mediterranean region showed that intense precipitation events in Allos (east of the Rhône Valley) were out of phase with events in the Cévennes (west of the Rhône) but in phase with events in eastern Spain. Supported by meteorological analyses, this suggests an oscillation in atmospheric circulation patterns over the northwestern Mediterranean.
Published: 2012
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35. The Holocene deposits of Lake Petit (2200 m a.s.l., Southern French Alps) : climatic and anthropogenic controls on mountain sediment dynamics ?

Author: Franck Sumera, Fabien Arnaud, Cécile Miramont, Bruno Wilhelm, Christine Paillès, Elodie Brisset, Jean-Robert Disnar, Claire Delhon, Frédéric Guiter, Edward J. Anthony, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre d'Études Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Centre Camille Jullian - Histoire et archéologie de la Méditerranée et de l'Afrique du Nord de la protohistoire à la fin de l'Antiquité (CCJ), Aix Marseille Université (AMU)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
Subjects: Mediterranean climate, Palynology, 010506 paleontology, geography, geography.geographical_feature_category, Sediment, Massif, 15. Life on land, 010502 geochemistry & geophysics, 01 natural sciences, Deposition (geology), Oceanography, Productivity (ecology), [SDU]Sciences of the Universe [physics], Period (geology), Geology, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: International audience; Numerous archaeological studies carried out in high-elevation areas of the Southern French Alps have documented ancient human occupation of mountains, mainly characterized by pastoral and mining activities. Besides, the area was affected by both continental and Mediterranean climate instability throughout the Holocene. Lake Petit, located in the Mercantour massif, was investigated in order to reconstruct past interactions between humans, the environment and climate, using a multidisciplinary approach. This study was carried out on a 144 cm-long gravity core providing a continuous record spanning the last 5000 years. Our multi-proxy investigation (sedimentological, geochemical and palynological analyses), allowed us to reconstruct three main phases, evidencing a progressive destabilization of the local environment. The first phase (ca. 4800 to 4300 cal. BP) was characterized by relatively stable environmental conditions, as attested by a high lake productivity (deposition of pure diatomite) and by the local presence of trees (presence of conifer stomata). The second phase (ca. 4300 to 1500 cal. BP) could correspond to a drastic cleaning of landscapes since the lake record highlights an abrupt switch in sediment source marked by an input of terrestrial organic matter. Regular occurrences of anthropogenic pollen assemblages might indicate early pastoral activity in the lake vicinity, while wetter conditions characteristic of the Neoglacial period may have trigger hillslopes destabilization. The most recent phase (since ca. 1500 cal. BP) is marked by a final degradation of the environment: the lake productivity dramatically decreased contemporaneously with a fall of the AP/NAP pollen curve. This phase also exhibits the highest values of anthropogenic pollen taxa and concentrations of lead. It undoubtedly corresponded to one of an intensive agro-pastoral pressure as well to local mining activities.
Published: 2011

36. The Alpine mediterranean highlands : geosystems under long-lasting natural and anthropogenic pressures (Millefonds catchment, southern alps, France )

Author: Elodie Brisset, Frédéric Guiter, Cécile Miramont, Claire Delhon, Fabien Arnaud, Kazuyo Tachikawa, Marta Garcia, Jean-Robert Disnar, Jean-Dominique Meunier, Pagès Gaspard, Bruno Wilhelm, Christine Paillès, Franck Sumera, Edward Anthony, Edouard Bard, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Culture et Environnements, Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Service Interdisciplinaire sur les Systèmes Moléculaires et les Matériaux (ex SCM) (SIS2M UMR 3299), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut de Recherches sur les Archéomatériaux (IRAMAT), Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne-Centre National de la Recherche Scientifique (CNRS), Centre Camille Jullian - Histoire et archéologie de la Méditerranée et de l'Afrique du Nord de la protohistoire à la fin de l'Antiquité (CCJ), Aix Marseille Université (AMU)-Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS), Géochimie & géochrono, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Chaire Evolution du climat et de l'océan, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Collège de France - Chaire Evolution du climat et de l'océan, Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université de Technologie de Belfort-Montbeliard (UTBM)-Université d'Orléans (UO)-Université Bordeaux Montaigne (UBM)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE]Environmental Sciences, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology
Abstract: Mediterranean mountains are very sensitive geosystems to erosion processes. These environments combine three steep gradients: topographic, ecologic and climatic. They are extremely vulnerable to both anthropogenic and climate-driven global changes. We propose a multiproxy approach from sediments sequence of Petit Lake (2200m, Millefonts catchment, Mercantour massif, France). We combine sedimentological, geochemical and palaeoecological analyses in order to resolve conjointly each compartment of this high elevation geosystem: vegetation dynamics, lacustrine productivity variability, modalities and rhythms of erosion processes. The 5 millennia drastic collapse of the geosystem is the result of intense precipitations on slopes already affected by human activities (e.g. pastoralism, ore smelting). Natural and Human agencies are necessary both the causes of landscape disturbance of this environment.
Published: 2011

37. Structure and dynamics of ecosystems during the recent glaciations of the Quaternary in Medio-European and Mediterranean areas

Author: Valérie Andrieu-Ponel, Jacques-Louis de Beaulieu, Soumaya Belmecheri, Svante Björck, Simon Brewer, Jacques Brulhet, Pascal Campagne, Coste, G., Emmanuel Gandouin, Frédéric Guiter, Didier Kéravis, George Kukla, Elisabeth Lallier-Vergès, Michelle Leydet, Gérard Nicoud, Philippe Ponel, Frank Preusser, Maurice Reille, Patrick Rioual, Nicolas Thouveny, Daniel Veres, Linda Ampel, Ulrich von Grafenstein, Barbara Wohlfarth, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, University of Utah, Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), and Leydet, Michelle
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2010

38. Organisation et dynamique des écosystèmes pendant les glaciations récentes du Quaternaire dans les régions médio-européennes et méditerranéennes

Author: Valérie Andrieu-Ponel, Jacques-Louis de Beaulieu, Soumaya Belmecheri, Svante Björck, Simon Brewer, Jacques Brulhet, Coste, G., Emmanuel Gandouin, Frédéric Guiter, Didier Kéravis, George Kukla, Elisabeth Lallier-Vergès, Michelle Leydet, Gérard Nicoud, Frank Preusser, Maurice Reille, Patrick Rioual, Nicolas Thouveny, Daniel Veres, Linda Ampel, Ulrich von Grafenstein, Barbara Wohlfarth, Leydet, Michelle, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), University of Utah, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2010

39. 10,000 years of vegetation history of the Aa palaeoestuary, St-Omer Basin, northern France

Author: Valérie Andrieu-Ponel, Jacques Brulhet, Philippe Ponel, Brigitte Van Vliet-Lanoë, Morteza Djamali, Maryse Alvitre, Emmanuel Gandouin, Jacques-Louis de Beaulieu, Evelyne Franquet, Murielle Meurisse, Marcel Brocandel, Frédéric Guiter, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Processus et bilan des domaines sédimentaires (PBDS), Université de Lille, Sciences et Technologies-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Domaines Océaniques (LDO), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Observatoire des Sciences de l'Univers-Institut d'écologie et environnement-Centre National de la Recherche Scientifique (CNRS), Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA), and Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1
Subjects: 010506 paleontology, human impact, Fluvial, Wetland, Structural basin, 010502 geochemistry & geophysics, medicine.disease_cause, 01 natural sciences, Pollen, medicine, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Ecology, Paleontology, 15. Life on land, Preboreal, pollen analysis, Paleobotany, Subatlantic, flood plain, Physical geography, medicine.symptom, Vegetation (pathology), [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, marine transgression
Abstract: International audience; The analysis of sediments and pollen from three sedimentary profiles in the St-Omer basin (Pas-de-Calais, France) has allowed the reconstruction of local and regional vegetation history from the late Preboreal to the Subatlantic. Hydrological changes induced vegetation changes, with freshwater marshy vegetation dominating during fluvial episodes, and halophilous grasslands, typical of shore areas, dominating during episodes of salt water input (five marine episodes, so-called St-Omer I to St-Omer V). Pollen markers indicative of human presence and agricultural activities, along with contemporaneous signals of forest disturbance, are recorded from ca 4000 cal BP onwards.
Published: 2009
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40. A late Holocene pollen record from Lake Almalou in NW Iran: evidence for changing land-use in relation to some historical events during the last 3700 years

Author: Emmanuel Gandouin, Mojtaba Salimian, Valérie Andrieu-Ponel, Manuel Berberian, Philippe Ponel, Frédéric Guiter, M. Shah-Hosseini, Jacques-Louis de Beaulieu, Naomi F. Miller, Hamid Lahijani, Morteza Djamali, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), AUTRES, University of Pennsylvania Museum of Archaeology and Anthropology (Penn Museum), Iranian National Center for Oceanography, and Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1
Subjects: 010506 paleontology, Archeology, History, 010504 meteorology & atmospheric sciences, Environmental change, Climate change, Wetland, Iran, medicine.disease_cause, 01 natural sciences, Pollen, medicine, Holocene, 0105 earth and related environmental sciences, 2. Zero hunger, geography, geography.geographical_feature_category, Sahand, Vegetation, 15. Life on land, Archaeology, 13. Climate action, Iron Age, [SDE]Environmental Sciences, Period (geology), Anthropogenic activities, Pollen record, Fruticulture
Abstract: International audience; A pollen diagram was prepared from Lake Almalou, a volcanic crater wetland located on the eastern flanks of the Sahand Volcanic Complex in NW Iran. The core provides a 3700-year record of human activity and environmental change in an upland region. We attempt to relate vegetation changes to both climatic change and historical events. Variations of anthropogenic pollen indicators suggest several phases of intensified human activities. Two strongly expressed agricultural phases are dated at about 2450-2220 cal BP (Achaemenid Empire) and 230-30 cal BP (collapse of Safavid Dynasty to the modern period). Historical rather than climatic events appear to be the main controlling factors for upland land-use dynamics. Fru-ticulture has been practiced in the region at least since the Iron Age, reaching its maximum importance 1500-1250 cal BP during the reign of Sassanid Empire; it declined by the time of Islamic conquest of Iran (651 AD). The Little Ice Age is tangibly recorded by higher lake water levels most probably due to both lower summer temperatures and higher annual precipitations. Low values of cereal-type and cultivated tree pollen during this period may indicate a change in the lifestyle from the cultivation of fields and orchards to a more nomadic life dominated by summer pasture. The modern period (1850 AD onwards) is characterized by expansion of agricultural activities to upland areas and intensified pastoralism.
Published: 2009
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41. Vegetation and climate changes in the French Alps for the last 140 000 yr

Author: Valérie Andrieu-Ponel, Jacques-Louis de Beaulieu, Soumaya Belmecheri, Simon Brewer, Jacques Brulhet, Emmanuel Gandouin, Frédéric Guiter, George Kukla, Elisabeth Lallier-Vergès, Michelle Leydet, Anson Mackay, David Morley, Gérard Nicoud, Philippe Ponel, Frank Preusser, Maurice Reille, Patrick Rioual, Nicolas Thouveny, Daniel Veres, Ulrich von Grafenstein, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), University of Utah, Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, and Leydet, Michelle
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2009

42. [Pollen analysis from two littoral marshes (Bourdim and Garaat El-Ouez) in the El-Kala wet complex (North-East Algeria). Lateglacial and Holocene history of Algerian vegetation]

Author: Mohamed, Benslama, Valérie, Andrieu-Ponel, Frédéric, Guiter, Maurice, Reille, Jacques-Louis, de Beaulieu, Jérémy, Migliore, and Morteza, Djamali
Subjects: Geologic Sediments, Quercus, Algeria, Climate Change, Wetlands, Radiometric Dating, Pollen, Pinus, Poaceae, Cedrus, Ecosystem, History, Ancient, Trees
Abstract: The study of two pollen sequences from El-Kala marshes allowed the reconstruction of the regional vegetation history supported by eight radiocarbon dates. Pollen assemblages from Bourdim site were dominated by local input of Alnus and Salix, while regional vegetation was characterized by scattered Quercus suber forests with a well-developed Erica arborea matorral. While the vegetation dynamics recorded at Bourdim is recent (Late Holocene), the majority of the pollen diagram from Garaat El-Ouez is contemporaneous to the Late Pleniglacial and is characterized by open woodlands with Pinus, Poaceae and several heliophilous herbs. The significant values of Cedrus pollen identified in this period indicate that the region of El-Kala most probably played the role of a refugium for this tree.
Published: 2009

43. Palynostratigraphy of some Pleistocene deposits in the Western Alps: A review

Author: Frédéric Guiter, Jacques-Louis de Beaulieu, Bernard Blavoux, Philippe Ponel, Gérard Nicoud, Valérie Andrieu-Ponel, Emmanuel Gandouin, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Avignon Université (AU), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Hydrogéologie d'Avignon (LHA), and Environnements, Dynamiques et Territoires de la Montagne (EDYTEM)
Subjects: Palynology, 010506 paleontology, 010504 meteorology & atmospheric sciences, Pleistocene, Outcrop, [SDE.MCG]Environmental Sciences/Global Changes, Context (language use), 01 natural sciences, Paleontology, Interglacial, [SDE]Environmental Sciences, Sedimentary rock, Stadial, Glacial period, Geology, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: International audience; In the Alps, interglacial and interstadial deposits are rarely preserved due to the intense erosive effect of glaciers in the valleys. Fortunately, some outcrops and cored sequences located in the field area ranging from Lyon to Evian provided sedimentary profiles datable by palynostratigraphy in a highly documented geomorphological context. An overview of several palynological sequences studied in this large area is proposed, and their position in a general chronostratigraphical pattern is discussed. Particular attention is paid to palynostratigraphical evidence whose relevance is tested with systematic comparisons with long reference European pollen sequences spanning several glacial cycles. Minimum ages are suggested for non-glacial episodes corresponding to the deposits studied. r
Published: 2008
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44. Contrôle de la construction de l'ensemble détritique de la région d'Evian par trois phases glaciaires durant le Würm

Author: Bernard Blavoux, Frédéric Guiter, Gérard Nicoud, Anne Triganon, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010506 paleontology, würm, lemanic basin, 010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, datation, ensemble détritique, glaciation, glaciaire, Geology, speed fluctuations, deglaciation, 01 natural sciences, 13. Climate action, Würm, fluctuations rapides, bassin lémanique, marge glaciaire, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, dating, 0105 earth and related environmental sciences, Earth-Surface Processes
Abstract: La réalisation récente de sondages carottés sur l’ensemble du versant d’Evian permet de réaliser des observations détaillées des dépôts détritiques d’épaisseur hectométrique. Ceux-ci sont constitués de sédiments hétérogènes de type glacio-lacustre, glaciaire de fond, glaciaire latéral, avec de nombreux dépôts ligneux et tourbeux. Trois complexes sont mis en évidence, du plus ancien au plus récent :• un complexe inférieur, à dominante glacio-lacustre, mis en place avant 30 000 ans, mais après le maximum glaciaire würmien,• un complexe dit du « Plateau de Gavot », de marge glaciaire active, accumulé entre 30 000 et 27 000 BP. Il enregistre une quinzaine d’oscillations latérales du glacier du Rhône dont certaines de plus d’un kilomètre,• un complexe emboîté, riche en sédiments glacio-lacustres, mis en place entre 25 000 et 21 000 ans BP. Il correspond vers l’aval, à Thonon, à la limite entre les hautes et les basses terrasses de kame. Recent corings have been carried out in the Evian area, allowing us to describe in details new hectometric profiles of detritical sedimentary deposits. Various sediments have been observed throughout the Quaternary sequences: glacio-lacustrine facies, basal and lateral till, and organic-rich layers (including lignite and peat). Three major stratigraphical units have been identified:• The “Complexe Inférieur”, mainly composed of glacio-lacustrine sediments, dated before 30 000 yr B.P. and prior to the L.G.M.• The “Complexe du Plateau Gavot”, deposited between 30 000 and 27 000 yr B.P., in the sedimentological context of active glacial margin.Therefore, this unit recorded at least fifteen lateral fluctuations of the Rhône glacier margin. Some oscillations could have exceeded one kilometer of extension in latitude,• The “Complexe emboîté”, mainly composed of glacio-lacustrine sediments, deposited between 25 000 and 21 000 yr. BP. This Unit fits well with the boundary between high and low kame terraces located in the surroundings of Thonon-Les-Bains.
Published: 2008

45. Réponse des écosystèmes ouest-européens aux fluctuations rapides du climat (Heinrich et Dansggard-Oeschger) pendant le glaciaire wurmien (OIS 4 à OIS 2)

Author: Valérie Andrieu-Ponel, Linda Ampel, Jacques-Louis de Beaulieu, Soumaya Belmecheri, Svante Björck, Simon Brewer, Jacques Brulhet, Coste, G., Emmanuel Gandouin, Frédéric Guiter, Didier Kéravis, George Kukla, Elisabeth Lallier-Vergès, Michelle Leydet, Anson Mackay, David Morley, Gérard Nicoud, Philippe Ponel, Frank Preusser, Maurice Reille, Patrick Rioual, Nicolas Thouveny, Daniel Veres, Ulrich von Grafenstein, Barbara Wohlfarth, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, University of Utah, Leydet, Michelle, and Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2008

46. Response of the Western-European ecosystems to rapid climatic fluctuations (Heinrich and Dansggard-Oeschger) during glacial times (OIS 4 to OIS 2)

Author: Valérie Andrieu-Ponel, Linda Ampel, Jacques-Louis de Beaulieu, Soumaya Belmecheri, Svante Björck, Simon Brewer, Jacques Brulhet, Coste, G., Emmanuel Gandouin, Frédéric Guiter, Didier Kéravis, George Kukla, Elisabeth Lallier-Vergès, Michelle Leydet, Anson Mackay, David Morley, Gérard Nicoud, Philippe Ponel, Frank Preusser, Maurice Reille, Patrick Rioual, Nicolas Thouveny, Daniel Veres, Ulrich von Grafenstein, Leydet, Michelle, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, University of Utah, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDE] Environmental Sciences, [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2008

47. Insect evidence for environmental and climate changes from Younger Dryas to Sub-Boreal in a river floodplain at St-Momelin (St-Omer basin, northern France), Coleoptera and Trichoptera

Author: Philippe Ponel, Evelyne Franquet, Valérie Andrieu-Ponel, G. Russell Coope, Brigitte Van Vliet-Lanoë, Jacques Brulhet, Marcel Brocandel, Emmanuel Gandouin, Frédéric Guiter, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), University of London [London], Processus et bilan des domaines sédimentaires (PBDS), Université de Lille, Sciences et Technologies-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA), and Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU)
Subjects: 010506 paleontology, Floodplain, Range (biology), Lateglacial, Fauna, [SDE.MCG]Environmental Sciences/Global Changes, Holocene climatic optimum, Palaeoenvironment, 010502 geochemistry & geophysics, Oceanography, Palaeoclimate, 01 natural sciences, Younger Dryas, Ecology, Evolution, Behavior and Systematics, Holocene, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, Ecology, Trichoptera, Paleontology, 15. Life on land, Coleoptera, Boreal, 13. Climate action, [SDE]Environmental Sciences, MCR, Chronozone, Physical geography, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, Geology
Abstract: International audience; The St-Omer area is a rapidly subsiding basin in which long sequences of Weichselian and Holocene sediments are preserved. A core 21 m long, extracted from near St-Momelin about ten km north of St-Omer, has been analysed for insect fossils. Four Faunal Units (SMi-1 to SMi-4) are described based on changes in both coleopteran and trichopteran assemblages. The basal Faunal Unit (SMi-1) includes many cold-adapted species and is attributed to the Younger Dryas chronozone. The transition to Holocene sedimentation was abrupt. Faunal units SMi-2 to SMi-4 are attributable to the Holocene. They lack all the cold-adapted species found in the basal sediments and in their place are insect assemblages very similar to the present day fauna in this region. This sequence spans the period from the Pre-Boreal to the Sub-Boreal. Faunal Unit SMi-2 includes insects from the Pre-Boreal, the Boreal and most of the Atlantic periods. This fauna was fairly sparse and made up largely of species living in freshwater habitats. The Faunal Unit SMi-3 includes the insect assemblages from the Late-Atlantic to Sub-Boreal periods. This fauna was much more diverse and indicated a river meandering across its floodplain and bordered by a mature forest at a time when the climate was warmer than that of the present day. This chronostratigraphical sequence of events is supported by 14C dates and by lithological data. Thermal climatic conditions have been quantified using the Mutual Climatic Range method. During the Younger Dryas period (SMi-1), Tmax (the mean July temperature) was in the region of 10 °C and Tmin (the mean temperature of January/February) was close to − 11/− 12 °C. After the sudden climatic amelioration at the start of the Holocene (SMi-2 to SMi-4) Tmax probably fluctuated throughout the early Holocene between 16 °C to 19 °C and Tmin between 0 °C to 5 °C; figures that are close to those of the present day. This climatic history is compared with others in northern Europe.
Published: 2007
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48. Past environment and climate changes at the last Interglacial/Glacial transition (Les Échets, France) inferred from subfossil chironomids (Insecta)

Author: Elisabeth Lallier-Vergès, Jacques Brulhet, Daniel Veres, Valérie Andrieu-Ponel, Jacques-Louis de Beaulieu, Emmanuel Gandouin, Maurice Reille, Frédéric Guiter, Philippe Ponel, Didier Kéravis, Ulrich von Grafenstein, Evelyne Franquet, Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA), Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochrononologie Traceurs Archéométrie (GEOTRAC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Department of Physical Geography and Quaternary Geology, Stockholm University, The study is part of a large multiproxy palaeoecological program supported by ANDRA, CNRS, NSF, the Lund University and IMEP., Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)
Subjects: 0106 biological sciences, 010506 paleontology, Pleistocene, [SDE.MCG]Environmental Sciences/Global Changes, Mid Europe, Palaeoenvironment, Biozone, Lake water level, 01 natural sciences, Paleolimnology, Chironomids, Palaeolimnology, 92.60.Ry, Littoral zone, Climate change, 14. Life underwater, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, 0105 earth and related environmental sciences, Global and Planetary Change, Eemian, Subfossil, Ecology, 010604 marine biology & hydrobiology, 15. Life on land, Geography, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Interglacial, General Earth and Planetary Sciences
Abstract: International audience; Subfossil chironomid assemblages spanning the last Interglacial/Glacial transition at Les Échets (France) highlight the environmental and climatic changes that took place at this crucial period. The Early Eemian warming is marked by increased percentages of warmwater taxa and decreased percentages of coldwater taxa. In the Middle Eemian, a lowering in water level is indicated by a rise of littoral taxa. In the Late Eemian, chironomids indicate anoxic deep waters and rise of water level, probably induced by increased rainfall. Mélisey I and II and the beginning of the glacial period are marked by the reappearance of coldwater taxa, lower percentages of warmwater taxa, and dominance of littoral taxa, probably correlated with lower water level and climate aridity. St Germain I and II are marked by higher percentages of warmwater taxa, lower percentages, or absence of both coldwater and littoral taxa.
Published: 2007
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49. [Palynological evidence of anthropogenic pressure: effect on pollination dynamics in the Evian area since the middle Neolithic: the pollen record of La Beunaz (971 m a.s.l., northern Alps, France)]

Author: Frédéric, Guiter, Valérie, Andrieu-Ponel, Jacques-Louis, de Beaulieu, Philippe, Ponel, Gérard, Nicoud, and Bernard, Blavoux
Subjects: Geography, Fossils, Plant Development, Pollen, Germination, Carbon Radioisotopes, France, Environment, Plant Physiological Phenomena, Demography
Abstract: This paper presents a pollen diagram from La Beunaz peat-bog (southeast of Evian, Haute-Savoie, France), which provides the first detailed record of human impact on vegetation of the southern bank of Lake Geneva since the Middle Neolithic. The radiocarbon-dated pollen profile is correlated with micro-charcoal record and archaeological data. The results suggest that several phases of deforestations since 4615+75/-70 years BP occurred, in relation to human activities (agriculture, pastoralism). Tombs and vestiges of lacustrine villages indicate that the region was intensively and recurrently occupied by man during at that time.
Published: 2005

50. Impact anthropique sur la végétation de la région d'Évian depuis le Néolithique moyen : l'enregistrement pollinique de la Beunaz (971 m n.g.f., Haute-Savoie, France)

Author: Valérie Andrieu-Ponel, Frédéric Guiter, Philippe Ponel, Jacques-Louis de Beaulieu, Bernard Blavoux, Gérard Nicoud, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
Subjects: 2. Zero hunger, 010506 paleontology, General Immunology and Microbiology, [SDE.MCG]Environmental Sciences/Global Changes, Néolithique, Forestry, General Medicine, 15. Life on land, 010502 geochemistry & geophysics, Vegetation dynamics, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Haute-Savoie, Anthropisation, Geography, 13. Climate action, France, General Agricultural and Biological Sciences, Anthropogenic factor, Micro-charbons, Analyse pollinique, [SDU.STU.AG]Sciences of the Universe [physics]/Earth Sciences/Applied geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: Resume L'etude paleoecologique d'un profil sedimentaire preleve dans la tourbiere de la Beunaz (au sud-est d'Evian, Haute-Savoie, France) a permis, pour la premiere fois, de reconstituer en detail l'evolution de la vegetation du plateau d'Evian. Les donnees polliniques, radiometriques et micro-anthracologiques ont montre que le couvert forestier a subi de profondes perturbations des 4615 + 75 / – 70 ans BP, notamment en raison d'episodes reguliers de deforestation. Il s'agissait probablement de defrichements a vocation agro-pastorale, car de nombreux vestiges archeologiques contemporains de ces periodes attestent une occupation humaine dense sur l'ensemble de la rive sud du lac Leman. Pour citer cet article : F. Guiter et al., C. R. Biologies 328 (2005).
Published: 2005

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