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[EN] The tempo and mode of colonization of the Iberian Peninsula (IP) by Cannabis sativa, its further internal spreading and the potential cultural and environmental factors involved remain unknown. The available continental-wide European meta-analyses using pollen and archeological evidence account for only a few IP sites, insufficient for a sound assessment. This paper presents a nearly comprehensive database of almost 60 IP sites with palynological evidence of Cannabis and analyzes the corresponding spatiotemporal patterns. The first scattered records of this pollen type date from the Middle and Upper Paleolithic (150–12 kyr BP) and would have entered the IP by maritime Mediterranean or terrestrial continental pathways, or both. A first burst of introductions, probably in a cultivated form, would have occurred during the Neolithic (7–5 kyr BP) using similar paths. Human participation in these Neolithic introductions remains unclear but cannot be dismissed. A period of reduced Cannabis arrivals (mostly via maritime pathway) occurred between the Chalcolithic and the Roman Epoch (4.5–2 kyr BP), when the innermost parts of the IP were colonized (Late Bronze). A second, likely anthropogenic, introduction acceleration took place in the Middle Ages (1.5 kyr BP onward) using the Mediterranean and the continental pathways. Maximum cultivation and hemp retting activity was recorded during the Modern Ages (16th-19th centuries), coinciding with the increased demand of hemp fiber to supply the Spanish royal navy for imperial expansion and commerce. A potential link between Cannabis colonization/introduction bursts and climatic warmings has been observed that should be tested with future studies. Regional moisture variations seem to be less influential. Further efforts to enhance and improve the database used in this study are encouraged. The results of this paper should be compared with archeological and historical evidence to clarify the role of human migrations and cultural changes in the historical biogeography of Cannabis in the IP., Este artículo está sujeto a una licencia CC BY 4.0

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The vegetation of the National Park of Aigüestortes i Estany de St Maurici is the result of an interaction between climate, plant community dynamics and the human occupation of the territory. The OCUPA project aimed to reconstruct this interaction across the last millennia combining methods from palaeoecology and archaeology. The study focused primarily on the Sant Nicolau valley and built on the multidisciplinary analysis of the sedimentary archive of two lakes (Llebreta and Redó) and a number of archaeological sites located in shelters and outdoors. There is archaeological evidence of human presence since 9000 yr cal BP, and a continuous record since 7500 yr cal BP. At early stages, humans transformed the surroundings of the shelters occupied and lithic tools indicate contacts with locations far away (i.e., the Ebro plains). Since more than 3000 years ago, there has been human impact on the vegetation without interruption until present. Initially, the impacts were mostly related to livestock: use of fire to open grazing lands, soil erosion and, during the medieval period, forestry and eutrophication of lakes. The agriculture impact in the lower part of the valley (e.g., Llebreta) occurred about 2100 yr ago, although some cereal grains and tools for harvesting have been found for the Neolithic. In the medieval period, the impact was higher than during the last centuries. In general, the changes in the human land use approximately follow the major changes in climate, but the specific causal link is likely related to the social and cultural dynamics of a broader territory since the Neolithic., Para el sondeo y estudio mineralógico se ha contado con la colaboración de financiación adicional a través del proyecto «Multidisciplinary research consortium on gradual and abrupt climate changes, and their impacts on the environment (GRACCIE), CSD2007-00067, Programa Consolider 2007»