Human-environment interaction during the Mesolithic-Neolithic transition in the NE Iberian Peninsula. Vegetation history, climate change and human impact during the Early-Middle Holocene in the Eastern Pre-Pyrenees

The synthetic analysis of several pollen records from sub-Mediterranean lowland Pre-Pyrenean regions evidences expansion of forests during the Early Holocene in Northeastern Iberia and the establishment of dense deciduous broadleaf forests during the Holocene Climate Optimum. Pollen records show the broadleaf deciduous forests resilience against cooling phases during the Mid-Holocene period, with slight regressions of oak woodlands and expansion of conifers or xerophytic taxa contemporary to some cooling episodes (i.e. 8.2 and 7.2 kyr cal. BP). Major vegetation changes influenced by climate change occurred in the transition to the Late Holocene, in terms of the start of a succession from broadleaf deciduous forests to evergreen sclerophyllous woodlands. The lack of evidence of previous occupation seems to support the Neolithisation of the NE Iberian Peninsula as a result of a process of migration of farming populations to uninhabited or sparsely inhabited territories. In that context, remarkable changes in vegetation were recorded from 7.3 kyr cal. BP onwards in the Lake Banyoles area, where the establishment of permanent farming settlements caused the deforestation of oak woodlands. In La Garrotxa region, short deforestation episodes affecting broadleaf deciduous forests, together with expansion of grasslands and presence of Cerealia-t were documented in the period 7.4–6.0 kyr cal. BP. Finally, in the coastal area, where less evidence of Early Neolithic occupations is recorded, evidence of Neolithic impact is reflected in the presence of Cerealia-t in 6.5–6.2 kyr cal. BP, but no strong human transformation of landscape was carried out until more recent chronologies.This research was undertaken through the following projects: ‘Organización social de las primeras comunidades agrícola-ganaderas a partir del espacio doméstico: Elementos estructuralesy áreas de producción y consumo de bienes (HAR2012-38838-C02-01)/Arquitectura en madera y áreas de procesado y consumo de alimentos (HAR2012-38838-C02-02)’, funded by Ministerio de Economía y Competitividad- Subdirección General de Proyectos de Investigación (Spain), ‘The digital reconstruction of the prehistoric past: virtual reality and artificial intelligence for understanding social life in the Neolithic (2015ACUP00191)’, funded by La Caixa (RecerCaixa-Obra Social) and Associació Catalana d’Universitats Públiques (ACUP). The research has been carried out in the framework of the research group AGREST (2014 SGR1169).Peer reviewe