Session Q12

Session 1: The Quaternary environments of human occupations : dynamics, varaibilities and mutations vs. adaptations, territorial strategies and environmental modifications

Grégory Dandurand – INRAP Grand-Sud-Ouest / Poitiers, Anaëlle Vayssière – LGP / Meudon, Mathieu Rué – Paléotime et Marylise Onfray – Trajectoires, Paris

Over the past twenty years, increased geoarchaeological studies enable not only to reconstruct past environments and their morpho-sedimentary dynamics, but also to specify the formation processes of archaeological records. In return, the many archaeological results obtained from these investigations enable to reconstruct more accurately chronostratigraphic and chronocultural frameworks and to characterize the activity systems and space organisation of settlements and their exploited territories, from Paleolithic to historic period. Thus, are invited to this session all contributions which, involve a synthetic geoarchaeological approach dealing with social-environmental interactions with multidisciplinary work (i.e., geomorphology, stratigraphic analysis, micromorphology, geochemistry…). This will allow us to discuss some specific aspects to the geoarchaeological approach, such as taphonomy, scale of analysis and resilience. Therefore, we accept papers explaining the over- or under-representation of some periods of occupation due to problems of differential conservation of the remains. Moreover, through a local or regional approach, the question of anthropisation of soil and paleoenvironments according to the forcing human activities in quaternary systems are welcomed. Finally, we will pay special attention to questions such as the ability of environments to regenerate despite anthropo-disturbances and adaptability of human behaviours to the environment.

Session 2: Palaeoclimate, palaeoenvironmental and archaeological records from Middle/Late Pleistocene continental successions over the Mediterranean

Valentina Villa – LGP / Meudon, Alison Perreira – Ecole Française de Rome / Italie, Giovanni Zanchetta et Biagi Giaccio – Université de Pise / Italie

The impressive increase of palaeoenvironmental, palaeoclimatic but also archaeological data over the last few years has been decisive for the Western Europe Middle/Late Pleistocene studies. Recent works provided on continental successions from the Mediterranean basin and the Balkan’s area give a new vision of the landscape evolution that occurred in these territories. Recent advances in geochronology and tephrostratigraphy for this timescale have improved our ability to correlate various palaeoenvironmental records with confidence and accuracy thanks to robust chronological constrains available for these continental successions. This session aims to bring together specialists of different disciplines (paleolimnology, geomorphology, quaternary geology, geochronology, archaeology, paleoclimatology…etc) to discuss different aspects of the Middle to late Pleistocene landscapes evolution of the Mediterranean and then define the new targets for the future.

Session 3: Structures and dynamics of past and modern periglacial environments

Olivier Moine, Pierre Antoine– LGP / Meudon, Frédéric Bouchard et Antoine Séjourné – GEOPS / Orsay

Session en partenariat avec l’Association Française du Périglaciaire

Periglacial and glacial environments are complex entities requiring a comparison between their past and modern changes for a better understanding of their future evolution. This session aims to develop the links between two communities working on periglacial and glacial environments though at very different timescales. It will gather communications that will mainly focus on the importance of mutual enrichments that may result from the crossing of Quaternary and palaeoenvironmental reconstructions and associated structures with the study of environments and processes in the modern periglacial and glacial domains (Arctic).

In this context will be privileged:

(1) studies of past and/or modern periglacial structures (morphology, large ice wedge casts, thermokarst, etc.) and associated deposits (aeolian, fluvial, slope) and their dating resulting on a better understanding of processes and dynamics;

(2) studies on the dynamics of landscapes, palaeoenvironments and populations in periglacial areas at all timescales, whether it is in the recent Arctic domain or at mid-latitudes during glacial times to allow for past-modern comparisons and to arouse crossed discussions between concerned communities;

(3) studies presenting results from analogic or numeric models in connection with past and modern periglacial structures and environments.

Session 4: Continental biodiversity and the spatio-temporal variability of Quaternary environments

Salomé Granai – Geoarchéon et LGP / Meudon, Aline Garnier – LGP / Meudon et Yannick Miras – HNHP, MNHN-CNRS

In recent palaeoenvironmental studies, research has mainly focused on the correlations between local records and global climate events and rarely on fluvial, aeolian or anthropogenic sedimentary environments. This can be explained by the discontinuity and heterogeneity of these records and by the complex taphonomic interpretation of their biological content. This session aims to explore how the use of high-resolution multi-proxy analyses including the study of complementary micro and macro biological records preserved in these records allows to overcome the taphonomic constraints inherent to continental environments and to improve the accuracy of environmental interpretations. Besides these methodological considerations, this session focuses on the characterisation of temporalities (crises, trajectory) and transitional areas (changing boundaries of habitats) in biodiversity dynamics. Presentations of case-studies originating from all latitudes and concerning the Pleistocene and the Holocene are expected and will illustrate how bioindicators contribute to the discrimination of factors influencing spatial and temporal variabilities of Quaternary environments.

Session 5: Quaternary Geochronology: Coupling Methodological Advances to Innovative Case Studies

Mathieu Duval – Griffiths University / Australie, Sebastian Kreutzer – URAMAP-CRP2A / Bordeaux, Claire Rambeau – Université de Freiburg / Allemagne et Gilles Rixhon – Ecole Nationale du Génie de l’Eau et de l’Environnement / Strasbourg

Quaternary Geochronology is a scientific discipline in constant evolution. Unfortunately, the perfect dating method potentially applicable to all situations (i.e., regardless of the sedimentary context or the age range considered) does not exist. Hence, there is a continuous demand to improve the reliability of current dating tools and develop new techniques. This session will cover all chronometric and relative dating methods typically applied in Quaternary Geochronology (e.g., but not restricted to, luminescence, electron spin resonance, U-series, radiocarbon, Argon-Argon, cosmogenic nuclides, dendrochronology, tephrochronology, palaeomagnetism, biochronology, amino acid racemisation). We welcome both dating application studies and methodological investigations. Particular emphasis will be given to multi-techniques dating studies and applying new and innovative approaches (e.g., Bayesian modelling). The presentation of preliminary data and work in progress are equally welcome.

Session 6: Long-term environmental trajectories for sustainable ecosystem management and restoration

Laurent Lespez – LGP / Meudon, Didier Galop – GEODE / Toulouse, Laurent Schmitt – LIVE / Strasbourg et Axel Beauchamp – LETG / Caen

 Palaeoecological, palaeoenvironmental and geoarchaeological records provide valuable long-term perspectives on the dynamics of contemporary ecosystems¹. The hybridity or the novelty of the contemporary ecosystems prevent past systems from being used as a target for restoration projects². However, long-term studies contribute to the reconstitution of trajectories of biodiversity and/or the state and the functions of the ecosystems which support them. As such, they can contribute to the ontological reflexion of “what is natural” today. Furthermore, they are not simply useful to tell the story of ecosystem’s degradation under human pressure, but they are also useful to understand the role of legacies and anticipate tipping points in a context of climate and land use changes. Thus, the knowledge of ecosystem trajectories is crucial to characterize the recovery potential, the range of potential future dynamics and to open the discussion on expected functioning as well as the sustainability of ecological management and restorations. In this session, we would like to welcome researchers working on ecosystem trajectories and using them to develop reflections on sustainable management and restoration. All palaeo-records and environments are welcome (lakes, rivers, wetlands, forests, meadows, moors and heath…) as well as all regions of the world (temperate, tropical, polar, mountains...). The reference period can be the Quaternary, the Holocene but can also be focused on the last centuries (from modern times to the present).

¹ Willis, K.J., Birks, H.J.B., 2006. What is natural? The need for a long-term perspective in biodiversity conservation. science, 314, 5803, 1261-1265.

² Hobbs, R.J., Higgs, E., Hall, C.M., Bridgewater, P., Chapin, F. S., Ellis, E. C., ... & Jackson, S.T., 2014. Managing the whole landscape: historical, hybrid, and novel ecosystems. Frontiers in Ecology and the Environment, 12, 10, 557-564.

Session 7: Climatic response to orbital forcing, from the Pliocene to today

Gilles Ramstein, Franck Bassinot, Fanny Lhardy – LSCE / Gif-sur-Yvette et Thibaut Caley – EPOC / Bordeaux

 We begin to grasp the geographic and geological settings at the time of Greenland glaciation and the links between low levels of CO2 reached at the end of the Pliocene and the amplification of climatic response to orbital forcing. This session aims at documenting and better understanding how orbital changes affect the intensity and spectral content of Earth’s climate variations from the Plio-Pleistocene to the late Holocene. This session is, therefore, climatic processus-oriented and will focus on state-of-the-art results from models (transient simulation using EMICs as well as GCMs results) and from paleoclimatic reconstructions using continental, marine and ice records. By bringing together a wide spectrum of scientific communities working on past climate dynamic, the crux of this session will be to push forward future joint actions combining modelisation and paleo-data to improve our understanding of climatic evolution beyond the EPICA timescale and throughout the Mid-Pleistocene Transition.

Session 8: Role of climate and environment on the dynamics of human populations from their appearance to the establishment of civilizations.

Thibaut Caley, Bruno Malaizé – EPOC / Bordeaux, Antoine Souron et William Banks – PACEA / Bordeaux

 This session aims to better document and understand the links between climate and environmental changes and

(1) the evolution of the first hominids since their appearance until their dispersion and

(2)  the settlement of ancient or recent civilizations.

 To achieve these objectives, we solicit contributions that will compare recent data about the evolution of hominids and their settlements with the climatic and environmental reconstructions obtained from various natural archives (marine, continental or glacial) and using a wide range of parameters and / or proxies. The session will also be the opportunity to compare these "field" data with approaches based on numerical modeling of environmental and population changes.