Patterns of human occupation during the early Holocene in the Central Ebro Basin (NE Spain) in response to the 8.2 ka climatic event

Abstract

28 páginas, 4 figuras, 2 tablas ; The Central Ebro River Basin (NE Spain) is the most northern area of truly semi-arid Mediterranean climate in Europe and prehistoric human occupation has been strongly influenced by these unique environmental conditions. The Bajo Aragón region (SE Ebro River Basin) was intensively populated during the Early Holocene (9400 – 8200 cal. yr B.P.) but the settlements were abandoned abruptly at around 8200 cal. yr B.P. Modern climate conditions single out this region due to the harsh environment, characterized by the highest absolute summer temperatures of the Ebro River Basin. We propose that this "archaeological silence" was caused by the regional impact of the global abrupt 8.2 ka cold event. Available regional paleoclimate archives demonstrate the existence of an aridity crisis 8200 years ago that interrupts the humid Early Holocene. That environmental crisis would have forced hunter-gatherers groups from the Bajo Aragón to migrate to regions with more favourable conditions (i.e. more humid mountainous areas) and only return in the Neolithic. Coherently, archaeological sites persist during this crisis in the nearby Iberian Range (Maestrazgo) and the North Ebro River area (Pre-Pyrenean mountains and along the northwestern Ebro Basin). ; This work was part of the projects: "Palinología y Paleoclima: Cambios Climáticos y/o Antropogénicos y Evolución de la vegetación" funded by CSIC (Programa Intramural 2007-2008); "Los cambios climáticos abruptos y su influencia en los ecosistemas y las sociedades humanas en el Pirineo central y occidental" funded by the Aragón Regional Government (DGA) and two projects funded by the Spanish Inter-Ministry Commission of Science and Technology (CICYT): "Cambios climáticos rápidos en la Peninsula Ibérica basados en calibración de indicadores, series instrumentales largas y análisis de alta resolución de registros lacustres (Subproyecto CGL2006-13327-C04-01/CLI)" and "Cazadores-Recolectores del valle del Ebro (HUM 2005-02882)". A. Moreno, M. Morellón, M. Sebastián and MC. Sopena have benefited from a Marie Curie Outgoing International Fellowships (proposal 021673-IBERABRUPT), a DGA fellowship, a FPI fellowship and a FSE-MEC contract, respectively. ; Peer reviewed