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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.

Little is known about how areas of high ecological value and biodiversity hotpots will be impacted in the long-term by increasing anthropogenic pressure, added to future climate warming. One such example is the Romanian Carpathians, among the richest biogeographical regions in Europe in terms of biodiversity indicators and home to the largest unmanaged old-growth forests in Europe. This area is currently threatened by forest clearance and other anthropogenic land-use change, poor management practices and increased risk to wildfire. Peat bogs are among the most important palaeo-archives for the reconstruction of past environmental changes and disturbance regimes, with the potential to provide the longer-term perspective at a local to regional scale necessary for a sustainable management and restoration of these areas. Here we reconstruct late Holocene fire history and the relationship with anthropogenic disturbance, particularly mining, in a former mining area located in Lapus Mts, NW Romanian Carpathians, based on two peat sequences.To reconstruct past fire activity, we used sedimentary macroscopic charcoal and also employed macro-charcoal morphologies to determine the type of material burnt (wood, grass, forbs). Past local soil/bedrock erosion and regional atmospheric pollution from historical mining were reconstructed on the basis of abiotic sediment properties such as elemental geochemistry, magnetic mineral characteristics, organic matter content and particle size. Our results show clear variations in macro-charcoal concentration, which coincide with changes in the geochemical, magnetic and grain-size indicators. Specifically, increases in macro-charcoal concentration, particularly the wood charcoal morphotype, were shortly followed in both cores by marked increases in heavy metal concentration and by enhanced soil and bedrock erosion, as inferred from geochemical, magnetic and grain-size proxies. This suggests increased local disturbance during intervals with mining activities and indicates the likelihood that humans used fire to clear the forests and open the access to the mining sites. Such actions likely resulted in topsoil removal and bedrock left exposed to environmental and climatic factors. Over the last centuries, the recovery of the local environment is evident in the proxies, with low fire activity and low soil/bedrock erosion, which coincides with the cessation of local mining activities. By showing both impact and recovery of the landscape, our study offers insight into the past evolution of this area and can be used to predict future possible responses of the local environment to anthropogenic stressors.

International audience; The nutrient-poor grasslands of Western Europe are of major conservation concern because land use changes threaten their high biodiversity. Studies assessing their characteristics show that their past and ongoing dynamics are strongly related to human activities. Yet, the initial development patterns of this specific ecosystem remain unclear. Here, we examine findings from previous paleoecological investigations performed at local level on European grassland areas ranging from several hundred square meters to several square kilometers. Comparing data from these locally relevant studies at a regional scale, we investigate these grasslands' spatiotemporal patterns of origin and long-term dynamics. The study is based on taxonomic identification and radiocarbon AMS dating of charcoal pieces from soil/soil sediment archives of nutrient-poor grasslands in Mediterranean and temperate Western Europe (La Crau plain, Mont Lozère, Grands Causses, Vosges Mountains, Franconian Alb, and Upper-Normandy region). We address the following questions: (1) What are the key determinants of the establishment of these nutrient-poor grasslands? (2) What temporal synchronicities might there be? and (3) What is the spatial scale of these grasslands' past dynamics? The nutrient-poor grasslands in temperate Western Europe are found to result from the first anthropogenic woodland clearings during the late Neolithic, revealed by fire events in mesophilious mature forests. In contrast, the sites with Mediterranean affinities appear to have developed at earlier plant successional stages (pine forest, matorral), established before the first human impacts in the same period. However, no general pattern of establishment and dynamics of the nutrient-poor grasslands could be identified. Local mechanisms appear to be the key determinants of the dynamics of these ecosystems. Nevertheless, this paleoecological synthesis provides insights into past climate or human impacts on present-day vegetation.

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.

Unravelling the precise Holocene altitudinal fluctuation of the highland vegetation communities (>1800 m asl) in the Gredos Range (Central System, Spain) is challenging owing to the complexity of the long-term human-environmental interactions in the area. Aiming at improving the knowledge of these highland dynamics, a pedoanthracological analysis was conducted on six soil profiles located on the northern slope of the central sector of the Gredos Range, following an altitudinal transect between 2200 and 1700 m asl in the Las Pozas valley. The soil charcoal analysis revealed the long-term stability of the Leguminosae shrublands, which have dominated the landscape over 1800 m asl since the Early Holocene. The highest ancient timberline was stimated to be at approximately 1700 m asl in this valley, from the Early Holocene until the beginning of the Late Holocene. This ancient forest contained Pinus gr. sylvestris, with significant numbers of deciduous Quercus. However, scattered individuals or small groves of pioneer deciduous taxa (Betula sp., Populus sp., Salix sp., Maloideae and Prunus sp.) were found to have thrived over the timberline during the Early and Middle Holocene, especially between 1900 and 2000 m asl. The highest treeline was marked by Betula at 2100 m asl. Elevated values of charcoal concentration reflect the intense fire regime of the area. The pattern of fire events accumulation periods that can be inferred from the 23 dated charcoal samples is consistent with previous data, which supports an increase in fire frequency around 2000 cal yr BP, during the first reported period of significant human influence.

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.

This chapter was made possible by two coordinated project grants from Spain’s Ministry of Economics and Competitiveness (MEC), “El uso del fuego y la conformación de los paisajes en la Montaña cantábrica y el Pirineo oriental: estudio comparado de su evolución historica y tendencias actuales” (CSO2012-39680-C02-01), awarded to the Department of Geography, Urban Studies and Land Planning, Universidad de Cantabria and “Geohistoria ambiental del fuego en el Holoceno. Patrones culturales y gestión territorial desde el inicio de la ganadería y la agricultura en la montañana Cantábrica y Pirineo,” awarded to the Department of Geography, Universitat Autònoma de Barcelona (CSO2012-39680-C02-02). In addition, the project was funded by the Catalan government’s applied geography program, ‘Grup de Geografia Aplicada’ (AGAUR, Generalitat de Catalunya, 2014 SGR 1090). Raquel Cunill gratefully acknowledges the Government of the Principality of Andorra, for the research grant on Andorran Issues, APTA007-AND/2014.

Estanilles peat bog, located in the northeastern Iberian peninsula, was studied to determine the anthropogenic changes in the landscape over the past seven millennia. The pollen diagram and sedimentary charcoal analyses from this site permit us to reconstruct the landscape changes in an area of both Mediterranean and Atlantic influence. In addition, Montarenyo ombrotrophic peat bog was studied to strengthen the analysis of data from more recent centuries. This paper attempts a reconstruction of historical cultural landscapes using two complementary palaeobotanical proxies (pollen and charcoal) in high mountain environments. The macroscopic charcoal record shows a fire signal since 7500 cal. b.p. However, the relationship between fire frequency and human impact is not always linear. This divergence is linked to fuel availability and fire activity. Fire has been used repeatedly to clear ground and to maintain open areas, and has been a key tool for the management of these high mountain areas. The intensity of use of the landscape implies the expansion of agricultural areas into higher altitudes, including cereal cultivation above 2,200 m a.s.l., during the Middle Ages. The first clear human influence detected in the pollen percentage data is recorded between 6000 and 7000 cal. b.p. and, until present times, the greatest changes in vegetation and landscape history occurred during periods of particular specialization in socioeconomic activities during the Middle Ages.

The principal objective of this research is to determine the maximum elevation reached by the treeline, as well as its altitudinal variations and composition throughout the Holocene, in a high mountain zone of the Pyrenean range. The temporal intervals of pedoanthracological data begin in 11000 cal. b.p. with the oldest dated charcoal, permitting a study of the entire Holocene period with the capacity to analyze climatic and anthropic situations. This is the first study to apply analysis of soil charcoals to the meridional slope of the Pyrenees for this purpose, and also its first use in research on the Iberian Peninsula. Eight pedoanthracological sites were sampled in a transect from 2,000 to 2,600 m altitude, with an altitudinal resolution of 100 m. The spatial precision provided by this proxy allows us to show that the maximum extension of the upper forest line was 400 m above the current line. This suggests a complete change in the landscape of a zone that is now covered with pasture from 2,000 m to the peak (2,593 m). Although pre-Neolithic fires appear to have a primarily climatic component, the fire origins during and after this period are more complex and far from being explained by a single, unequivocal cause.

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.

[EN] Archaeological survey and test excavations were conducted at high altitude in the western Catalan Pyrenees since 2001 to 2010. Together with palaeoecological studies of lake cores and peat bogs, these studies (including a series of 27 radiocarbon dates) permit one to discuss human occupations of the high mountains from Mesolithic times to the early Bronze Age. We evaluate the role played by mountain areas in the development of prehistoric communities with particular attention to the process of postglacial colonization, the introduction and development of farming and other agricultural practices, as well as complementary economic activities like mining, charcoal-burning and lumber production, with particular attention to the relation of mountain communities to those of other regions., [ES] Este artículo presenta los resultados de las campañas realizadas desde 2001 a 2010 en áreas de alta montaña del Pirineo axial occidental de Catalunya, que han generado unos registros arqueológicos extensos y detallados, así como diversos análisis paleoecológicos de turberas y contextos lacustres. Gracias a las 27 fechas radiocarbónicas obtenidas, se documenta la secuencia del poblamiento prehistórico en medios alpinos y subalpinos desde las primeras evidencias de su ocupación, en el Mesolítico, hasta el inicio de la Edad del Bronce, fundamentalmente. Se proponen nuevas hipótesis para su explicación. Se ha prestando especial interés a los procesos de colonización postglacial de estos espacios, a la introducción de prácticas ganaderas e, hipotéticamente, agrícolas y a su evolución. Se han considerado además actividades complementarias como la minería, la producción de carbón y la extracción de madera, así como las relaciones de las comunidades humanas de ámbitos de montaña con las de otras áreas geográficas., Esta investigación ha sido financiada por los proyectos Prospeccions a l’alta muntanya del Pallars Sobirà (2002ACOM 00028), subvencionados por el Consell Comarcal del Pallars Sobirà y la Generalitat de Catalunya, y Arqueologia de l’Alta muntanya Pirinenca. Ocupació Humana i canvi climàtic al llarg de l’Holocè (2006EXCAVA00022) de la Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) de la Generalitat de Catalunya, dirigidos por Ermengol Gassiot Balbè (UAB). También se ha contado con aportaciones directas del Parc Nacional d’Aigüestortes i Estany de Sant Maurici entre los años 2004 y 2012 y de otras entidades de ámbito regional.

International audience; Depuis 2004, une recherche archéologique et paléoenvironnementale a pris corps dans les monta-gnes de Béarn et Bigorre. Elle se fonde sur trois volets : archéologie pastorale en haute vallée d'Ossau, menée par C. Calastrenc et M. Le Couédic, archéologie minière et métallurgique en Ossau et Aspe, menée par A. Beyrie et É. Kammenthaler, et recherches paléoen-vironnementales dans les vallées d'Ossau et du Gave, menées par D. Galop, C. Cugny et D. Rius. Reposant sur l'articulation des données recueillies grâce à ces différents chantiers, ce programme vise à appréhender les évolutions des économies et des sociétés monta-gnardes en confrontant les rythmes d'anthropisation des paysages aux transformations des systèmes d'exploitation pastoraux et miniers.

10 páginas., Superimposed on the long-term climate variability attributed to orbital forcing, there are other modes of variability covering timescales from interannual to millennial throughout the Holocene. Their signatures in climate proxy archives can differ substantially because of their lower magnitude and regional diversity. However, if identified they can yield better understanding of the physical mechanisms regionally linking causes and effects. Here we describe a high-resolution record of organic matter accumulation in the sediments of Burg lake (Pyrenees, NE Iberian Peninsula), as assessed using loss on ignition (LOI), and compare it with the ice rafted debris (IRD) indexes from the North Atlantic. The LOI record indicates two main phases in the water body, a lacustrine phase as a shallow lake and a palustrine phase as a fen. The latter covers the period 2600—7200 cal. yr BP and within it there is a high coherence between LOI and IRD, which indicates submillennial climate fluctuations in the Pyrenees that can be related to the North Atlantic influence. The Burg’s LOI record suggests wetter (and occasionally colder) situations in the Pyrenees during high IRD in the Atlantic (Bond oscillations). These fluctuations would likely affect the snow covered period in the mountains (winter and spring seasons) the most, the period in which Atlantic westerlies currently have higher influence on precipitation over the Pyrenees. These climatic oscillations could have favoured Abies penetration during the mid Holocene, as evidenced by increased pollen percentages of this taxon during low IRD values (drier conditions). The pollen record also suggests potential relationships between climate and human activity as early as at mid Holocene, as human-related cereals increase during all the low IRD periods. The human signature (charcoal, cereals) becomes particularly evident at around 2800 cal. yr BP; in this oscillation Pinus overtake Abies in the conifer response to low IRD.

The study of macroscopic charcoal particles from peat bogs has led to a better understanding of climate, vegetation and fire history, and human impacts. To determine the relationship between human activities and the role of fire events in vegetation change during the last 3300. cal yr BP, we present the results of a multi-proxy approach based on the analysis of sediment characteristics, sedimentary charcoal, organic matter and pollen, as well as historical sources. This multi-proxy research permits high resolution palaeoenvironmental and fire history reconstruction of a mountain area located in the southern central Pyrenees (Spain). In the Pyrenees, fire is typically attributed to human activities since the beginning of the Bronze Age and may be correlated with slash-and-burn cultivation, metallurgy and pasturing activities. The data indicate a good linkage between high fire signals and Poaceae and Cerealia pollen, which reveals the impact of agro-pastoral practices. This study also shows two periods, 2900-2650. cal yr BP and 1850-1550. cal yr BP, for which higher frequencies of fire occurred, suggested by high arboreal pollen (AP) concentrations, and confirming the need for arboreal biomass to sustain fires. From the beginning of the Middle Ages, it seems that a change occurred in the anthropogenic use of fire, from a tool for agro-pastoral forest clearance to a means of maintaining open spaces. © 2011 Elsevier B.V., This work was supported by 1) a research grant from the Comunitat de Treball dels Pirineus (2007ITT 00001): Environmental dynamic of the Pyrenees over the past 20,000 years: A study of the impact of changes in climate and land use on forest ecosystems for the development of possible scenarios (Dinàmica ambiental pirinenca dels darrers 20.000 anys: estudi de l'impacte dels canvis climàtics i dels usos del sòl sobre els ecosistemes forestals per a l'elaboració d'escenaris prospectius) and 2) a project of the Catalan government (Generalitat de Catalunya — 2006EXCAVA00022): Archaeology of the high Pyrenees mountains.

International audience

International audience

Les travaux d'archéologie pastorale entrepris à Anéou depuis 2004 sont inclus dans le PCR " Dynamiques sociales, spatiales et environnementales dans les Pyrénées centrales " co-dirigé par Ch. Rendu et D. Galop (CR au CNRS). Ils visent à saisir, à partir d'une zone atelier restreinte (l'estive d'Anéou), l'histoire et les transformations des systèmes d'estivage de la haute vallée d'Ossau dans la longue durée. La première étape de cette recherche comprend la prospection exhaustive des 1256 ha de ce quartier de pâturage (débutée en 2004) et la datation, par sondage, des principaux types de sites observés à partir des relevés de surface (entrepris depuis 2005). Fin 2006, 11 sondages avaient été réalisés qui documentaient principalement, l'âge du Bronze, la transition Antiquité/Haut Moyen âge et l'époque moderne. Les travaux 2007 se sont structurés sur les bases des deux campagnes précédentes (2005 et 2006). 18 sondages archéologiques ont été réalisés en première partie de campagne ; la deuxième partie a permis l'achèvement des prospections pédestres systématiques de l'estive avec GPS différentiel. Les 18 sondages réalisés visaient essentiellement à documenter le hiatus du VIIe au XVIIe siècle de notre ère. La difficulté à repérer, d'après les images de surface des sites, une catégorie d'arasement intermédiaire entre les structures à micro-relief et celles conservées sur plusieurs niveaux d'assises a contraint à choisir les constructions apparaissant comme les plus anciennes des structures en élévation. Ces dernières ont fait l'objet de 10 des 18 sondages réalisés. Les 8 autres sondages ont été consacrés à des structures à l'état de micro-relief et visaient à compléter l'approche diachronique des entités et des secteurs abordés.

International audience

Dans cet article on analysera l’histoire et les caractères des pratiques de gestion de l’espace forestière dans la plaine du Po, la plus grande plaine fluviale de la péninsule italienne, pendant le Moyen Âge. Pour faire ça, on utilisera en particulière les sources écrites, mais aussi archéologiques. L’article est divisé en trois partie: la première relative à la situation du haute Moyen Âge (VIIIe-XIe siècle); la deuxième relative à la situation du bas Moyen Âge (XIIe-XVe siècle) ; enfin la troisième reprend le transformation de le rapport entre homme et foret pendant ces siècles, influencée par l’évolution des pratiques de gestion de l’espace forestière. Fondamental a été la période entre l’XIe et le XIIe siècle, qui a changé radicalement le forme de gestion du paysage rural padane et, en conséquence, aussi le rapport entre homme et foret.