This axis is dedicated to the study of physico-chemical exchanges at the hydrosphere / biosphere / atmosphere interfaces. The research activities and associated projects focus on current and ancient soils and hydrosystems, and on the measurement of the anthropogenic pressures they undergo over time.
Interactions and transfers in soils and hydrosystems
The objective is to improve our knowledge of the interactions and transfers in the Critical Zone and the connections between its components (surface water, groundwater, soil, altered rocks, biocenoses). GEODE is particularly interested in hydrosystems and soils (peatlands, karst and alluvial aquifers, permafrost) which are essential in terms of water resources, climate regulation and biodiversity conservation. The group seeks to better understand their biogeochemical functioning and to quantify the impacts of the anthropogenic and natural forcings to which they are subjected. Innovative and interdisciplinary approaches (imaging, remote hydrodynamic monitoring, fine detection of contaminants) are thus developed to characterise the structure and spatio-temporal evolution of these often heterogeneous and inaccessible environments. It is also a question of specifying the interactions between the various compartments and objects of the Critical Zone (karst / peat bog, karst / lake, etc.) in order to respond to problems such as the location of reservoirs and springs or the drying up of rivers or lakes (e.g. in the Jura). One of the aims is to propose new management and preservation frameworks for these environmental environments. To do this, the group relies on the acquisition of high-resolution, long-term data.
It actively participates in the management of national observatories (OZCAR ➔ SNO KARST, SNO Tourbières, SNO H+, SNO RENOIR - RZA ➔ ZAAJ) and is involved in training and transmission for the setting up of observatories in developing countries (GDR Rift).
Paleoenvironments and geoarchaeology
Paleoclimatic reconstructions are an essential tool for understanding the Earth’s natural environmental variability in the past. Part of the research conducted in GEODE is to determine the magnitude and nature of climatic variations and anthropisation of the natural environment during the recent Quaternary (Tardiglacial and Holocene) in order to better understand current environmental variations associated with climate change. The group brings geological expertise (mineralogy, sedimentology, geochemistry, isotopy) to the study of natural and anthropised palaeoenvironments in interaction, at the laboratory scale, with projects developed within the BIODIV’, POLLUTION and SOPAST themes. The long-term relationship between humans and their environment is explored, in particular (1) the construction, management and transformation of territories and landscapes (e.g. mining environments and ancient exploitation of mineral resources), (2) the fluctuation of different populations and their impact and/or adaptation to a particular environment and its evolution linked to climatic variations (e.g. impact of the last deglaciation in mountainous massifs or boreal zones, impacts of sea level variations on coastal populations). The combined analysis of archaeological data and palaeoclimatic archives from geological outcrops, palustrine, lacustrine and coastal sedimentary archives allows the environmental context of human evolution and mobility to be determined.
