Quel statut pour les espaces de montagne durant l'âge du Bronze? Regards croisés sur les approches société-environnement dans les Pyrénées occidentales

National audienceAprès avoir été longuement négligé, le milieu montagnard apparaît désormais comme un terrain de recherche privilégié pour l'analyse des anthroposystèmes et, en particulier, pour celle des interactions entre les sociétés et leur environnement. Le développement récent de plusieurs programmes inter-disciplinaires ou fédératifs de recherches, tant dans les Alpes que dans les Pyrénées, révèle l'intérêt et les enjeux scientifiques qui s'y concentrent. Dans les Pyrénées, les travaux conduits au Pays basque illustrent tout l'intérêt de développer des approches inter-disciplinaires à grande échelle, diachroniques, et à l'appui de chronologies à haute résolution. En croisant les données environnementales et archéologiques, se dessine, outre la dynamique de peuplement, le caractère fonctionnel de certains espaces. Pastoralisme, agriculture, exploitations des ressources minérales, structurent alors le territoir

Cinq millénaires de métallurgie en montagne basque. Les apports d'une démarche intégrée alliant palynologie et géochimie isotopique du plomb

National audienceUne démarche intégrée alliant palynologie et géochimie isotopique du plomb a été engagée dans une tourbière du Pays Basque, au coeur d'une région reconnue comme étant un foyer métallurgique ancien. Elle permet de reconstituer l'histoire des activités minières et métallurgiques et d'en apprécier l'impact sur l'environnement forestier au cours des cinq derniers millénaires. Plusieurs phases d'activités ont été repérées entre le début du IIIè millénaire av. J.-C. et l'époque moderne (Bronze moyen, Bronze final, Antiquité, époque moderne). La plupart sont clairement associées à des indices polliniques de réduction du couvert forestier, toutefois il ressort que localement l'impact de la métallurgie au bois sur les forêts n'atteint son paroxysme qu'à partir des XVè-XVIè siècles

Quel statut pour les espaces de montagne durant l’âge du Bronze ?

Après avoir été longuement négligé, le milieu montagnard apparaît désormais comme un terrain de recherche privilégié pour l’analyse des anthroposystèmes et, en particulier, pour celle des interactions entre les sociétés et leur environnement. Le développement récent de plusieurs programmes inter-disciplinaires ou fédératifs de recherches, tant dans les Alpes que dans les Pyrénées, révèle l’intérêt et les enjeux scientifiques qui s’y concentrent.Dans les Pyrénées, les travaux conduits au Pays basque illustrent tout l'intérêt de développer des approches inter-disciplinaires à grande échelle, diachroniques, et à l'appui de chronologies à haute résolution. En croisant les données environnementales et archéologiques, se dessine, outre la dynamique de peuplement, le caractère fonctionnel de certains espaces. Pastoralisme, agriculture, exploitations des ressources minérales, structurent alors le territoire.After having been neglected for some time, mountain environments have now become an important research area for the study of anthropogenic impact on the environment and the interactions of societies with their environments. The recent development of several interdisciplinary programs in the Alps and in the Pyrenees reveals the interest and the scientific questions associated with these domains. In the Pyrenees, the work undertaken in the Basque Country illustrates the utility of the development of multidisciplinary research on a large scale, which is both diachronic and has a high resolution chronology. Combining environmental and archaeological data, allows us to present an image of population dynamics, and the function of certain spaces. Such areas were structured by activities such as pastoralism, farming and the exploitation of minerals

Environmental impact of early Basque mining and smelting recorded in a high ash minerogenic peat deposit

International audienceMore than four metres of core, covering almost 5000 years of deposition, were collected in a high ash minerogenic peat deposit located in the High Aldudes valley (Basque country), an area well known for its mineral abundance, exploited from Roman Times at least.Although minerogenic peatlands are not generally considered as the best archives to reconstruct past atmospheric metal deposition history, lead isotopic geochemistry demonstrates the integrity of the Pb record at least within the three upper meters; that is to say over the last four millennia.Zn, Cd and Cumay have been widely redistributed either by biological cycling, advective groundwater movements, or diffusional processes.Anthr opogenic lead input phases are clearly pinpointed by positive shifts in PbySc ratios with concomitant sharp drops in 206Pby207Pb ratios.They are often accompanied by significant declines in tree taxa, interpreted as increasing demand for wood to supply energy for local mining andyor metallurgical operations.Periods of mining andyor smelting activity are identified during Antiquity and Modern Times, and are also confirmed by textual and field evidence.Inputs from the Rio Tinto (Southern Spain), often invoked as a major lead contributor to the European atmosphere during Roman Times, were not detected here.This remote source was probably masked by local inputs. Other mining andyor smelting phases, only suspected by archaeologists, are here identified as early as the Bronze Age.Although the durations of these phases are possibly overestimated because of detrital inputs consequent to the release of lead from polluted soils over a long period of time after major pollutant inputs, the periods at which pollution peaks occur are in good agreement with archaeological knowledge and palaeo-botanical data.Thecombination of geochemical and palaeo-botanical techniques with field archaeology, therefore provides a powerful tool in studying the interaction of early human societies with their environment, as regards early mining and smelting

doi:10.1016/j.envpol.2007.06.054

Kinetically defined metal fractions mimic mobility aspects of heavy metals. Abstract Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (Q M1 ) and less labile (Q M2 ). In citrate extractions, total extractability (Q M1 þ Q M2 ) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar Q M1 /Q M2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth

Environmental impact of early palaeometallurgy: pollen and geochemical analysis

International audienceInterdisciplinary research was carried out in mid-level mountain areas in France with the aim of documenting historical mining and smelting activities by means of pollen and geochemical analyses. These investigations were made on cores collected in French peatlands in the Morvan (northern Massif Central), at Mont Lozère (southern Massif Central) and in the Basque Country (Pyrénées). Different periods of mining were recognised from Prehistory to modern times through the presence of anthropogenic lead in peat. Some of these were already known from archaeological dates or historical archives, especially for mediaeval and modern periods. However prehistoric ancient mining activities, as early as the Middle Bronze Age (ca. 1700 b.c.), were also discovered. They had all led to modifications in plant cover, probably related in part to forest clearance necessary to supply energy for mining and smelting

Revisiting and exploring Middle-Late Triassic vertebrate tracksites in Ardèche (southern France)

.

Unearthing the past. French peat bog reveals thousands of years of mining pollution

article écrit par M. Peplow paru dans les News de Nature (janv. 2004) résumant l’article Monna et al., 200