Actividad aluvial durante la Pequeña Edad del Hielo en Bardenas Reales de Navarra

The geomorphology, sedimentology and pedology of the most recent alluvial unit (360±101 to 216±89 14C cal BP) were studied in the Bardenas Reales Natural Park (Navarra province). This unit is either infilling former narrow channel sections, currently showing a terrace morphology (e.g. El Vedado), or insert on older morphopedosedimentary units with wide channel morphology (e.g. Salinero). It is composed of a sequence of slacked flood depositional units, centimetric in scale, with weak degree of soil development. The palaeoclimatic context is interpreted within a period of arid trend, characterised by a high hydroclimatic variability, and increase in the frequency of floods during Little Ice Age. Alluvial dynamics shows a high degree of geomorphic effectiveness as well as a very quick response to centennial scale climatic variability.