From pristine forests to high-altitude pastures: an ecological approach to prehistoric human impact on vegetation and landscapes in the western Italian Alps

1. This paper addresses the origin and development of the oldest prehistoric pasture in the timberline ecotone known so far in the Alps and its relation to anthropogenic pressure and natural climate change.
2. Paleoecological and geochemical techniques were applied on the Crotte Basse mire stratigraphy (2365 m asl, western Italy) to describe changes in vegetation composition, forest biomass, land use and fertilization between ca. 6400 - 1800 yrs cal BP.
3. Subalpine forests dominated by Pinus cembra occurred at very high-altitude up to ca. 5600 yrs cal BP, when a sharp contraction of woody vegetation took place. This major vegetation shift is matched by increasing charcoal input and markers of pastoral/grazing activities (pollen, dung spores, and forms of phosphorus) in the sediment sequence in this small basin.
4. Major phases of landscape change detected in our multiproxy record chronologically match intervals of cumulative probability density of 14C ages from nearby archaeological...