Paleovegetación tardiglaciar en el Norte de la provincia de León

Résumé

The palinologic study of three quaternary deposits situated on the southern slopes of the Cantabrian mountain range in the north of the province of León was carried out. The results obtained from these pollen profiles tell us the history of the vegetation in the León Mountains from the end of the glacial stages until the present day. The palaeovegetation of the study area during the Late-Glacial includes the chronological interval between 15,000 years BP and 10,000 years BP. From the climatic viewpoint this period is characterised by two phases of extreme drought and cold, between which there is a stage of improvement. The vegetal landscape recorded in the pollen sequences varies according to these climatic oscillations, so in the periods of greatest climatic harshness the pine groves were the most representative tree formations while herb and shrub vegetation occupied most of the territory. In turn the increase in humidity and temperature, which occurred during the Late-Glacial Interstadial, benefited forest development. The expansion of pines and birch trees can be observed in the pollen diagrams at the same time as the percentages of herbaceous pollen types decreased.