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The Mirambel woodland on the margins of the Millevaches plateau (Massif Central) is one of the few ancient broad-leaved woodlands in France. Historical sources show that it has occupied the same surface area for the past 250 years, despite being in a region that underwent considerable anthropogenic changes during this period. We explored the Mirambel's Holocene history and ancientness by means of soil charcoal analysis, chosen because of its high accuracy on a local scale. We excavated five pedoanthracological pits in the woodland and its open marginal spaces. The 29 radiocarbon dates ranged from the Atlantic (8700–5500 cal yr. BP) – Subboreal transition to the Subboreal (5500–2800 cal yr. BP) and Subatlantic (2800–0 cal yr. BP, i.e. AD 1950) periods, revealing the existence of fire events corresponding to six contemporaneous cultural periods: Neolithic (ca. 3877–2991 cal yr BC), Neolithic-Chalcolithic transition (ca. 2528–2525 cal yr BC), Protohistory (ca. 147 cal yr BC), Roman period (ca. 326–579 cal AD), Middle Ages (ca. 732–1187 cal AD), and contemporary times (ca. 1781 cal AD to present day). Three Tilia charcoal fragments dating from ca. 3717–2919 cal yr BC indicated the presence of a diversified Mid-Holocene deciduous woodland featuring Tilia and Acer nowadays-absent taxa in this area. Deciduous Quercus and Fagus sylvatica dominated most of the soil profiles, as they do nowadays in the woodlands. Other taxa (Salix, Corylus avellana, Betula) were identified, as well as in the current vegetation. The occurrence of Cytisus-type (Fabaceae) and Calluna vulgaris suggested that there were forest clearing phases at all the points sampled. Widely varying levels of abundances may reflect differences in the duration of these open phases.

This paper presents the use of soil charcoal analyses in order to identify the origin of a Nardus stricta grassland in a mountain system (Mont Lozere, France), and the use of environmental resources and the construction of a cultural landscape. Two opposing theories have been proposed to explain the origin of this open landscape (1450–1700 m altitude): natural or anthropogenic. The identification and radiocarbon dates of charcoal fragments of Fagus sylvatica, which were found in all of the pits located in the current grassland area and dated to 3695–3633 cal BC, demonstrate that this species has been present on the upper part of Mont Lozere since the Middle Neolithic. In addition, the presence of pioneer species (Betula, Salix, Corylus avellana), as well as mid- (Prunus cf avium) and late-successional species (F. sylvatica) supports the hypothesis that the grassland contained both pioneer and mature phases of forest landscapes. The 14C dates, ranging from c. 4200 cal BC to 1200 cal AD, show that fire events occurred with different climatic influences. Fire events may correspond to one or several fires in a short period at the scale of the slope. Moreover, the dates coincide with the early and extensive human impact detected in the Massif Central and Mont Lozere. To explain the regular occurrences of fire events from the Middle Neolithic to the Central Middle Ages, agro-pastoral clearings have been postulated, as have been identified in other areas in the Pyrenees and in the Alps. Such human impact may have been magnified, or least facilitated, by climatic conditions. Comparison with additional data (pollen, archaeology, ecology) demonstrates that this grassland area is not natural and corresponds to an ancient forested system that has been used and transformed by societies since the Neolithic, although climate change may have certainly affected this transformation. The aim of this research is to promote this cultural heritage in collaboration with the National Park of the Cevennes in order to protect its future.

Using an interdisciplinary methodology based on pedoanthracology, palynology and sedimentary charcoals, landscape transformation in the Pyrenees mountains during the Holocene is analyzed, with special attention to altitudinal variation in the treeline. The data sources were eight soil profiles on a transect at 2000–2600 m a.s.l. and a sedimentary record extracted from a very nearby peat bog at 2247 m a.s.l. The combination of three different proxies permits a more viable and qualitatively complementary data set, making it possible to better interpret the vegetation dynamic in this space through the Holocene. Analysis of the data showed that the Pyrenees landscape has undergone important changes during this period. The changing treeline is a good example. There is evidence of the decisive role of fire in the configuration of this landscape. Finally, this study shows that herding and agricultural uses over thousands of years in the study area have had a determining influence on the current configuration of the territory, equal to or more important than climatic factors.

International audience; This article uses a method that combines pedoanthracological and pedo-archaeological approaches to terraces, complemented with archaeological pastoral data, in order to reconstruct the history of ancient agricultural terraces on a slope of the Enveitg Mountain in the French Pyrenees. Four excavations revealed two stages of terrace construction that have been linked with vegetation dynamics, which had been established by analyses of charcoal from the paleosols and soils of the terraces. Pedo-archaeological descriptions of these terrace soils reveal their ancient origins and their long-term use. Their chronology was established by radiocarbon dating of single charcoal fragments and charcoal lenses originating in the paleosols. Combining radiocarbon dating with pedo-archaeology resulted in a more reliable chronology. Moreover, the Bronze Age was found to be a crucial period in the history of land-use. This study also highlights the role of fire in the construction of this land-use pattern.

Differences of collembolan communities within the organo-mineral A layer were studied in relation to physico-chemical changes in humus at nine sites of beech forests (Fagus sylvatica L.) and first generation spruce stands (Picea abies (L.) Karst.), planted on former beech forest 30 years ago (Central Pyrenees, France). Changes in humus form were caused by the spruce plantation and occurred mainly within the fermentation horizon where acidifying litter accumulation increased the horizon depth. The recent replacement of beech by spruce induced a shift from mull towards moder humus forms, which is explained by the decreasing organic matter turnover rate. A significant decrease in the three exchangeable cations and pH under spruce was also observed. Collembolan species diversity within the A horizon was significantly lower under spruce at this early stage of the silvogenetic cycle. Differences between species composition of Collembola between the two forest stands is related to changes in environmental conditions (e.g. nutrient availability, soil porosity, soil moisture). This study shows how forest management practices are susceptible to modify biological activity within the A horizon under exotic conifer plantations.