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a b s t r a c tThis 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.

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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.

Proper management of the perceived value of any geographic space requires the capacity to interpret research results from spatial, temporal, and environmental points of view, applying the principles of environmental geohistory. Basic concepts such as baseline, threshold, or resilience are discussed from a long-term ecological perspective, with examples that explain the dynamics of fir forests as well as the changes in agricultural cover. Studying the changes in the altitudinal limit of the forest and surveying the wetlands dynamics on the southern slopes of the central Catalan Pyrenees have been shown to be effective tools to develop appropriate management tasks. The arguments presented are useful to enrich the public debate over management policies for natural protected spaces in high-mountain areas.

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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.