yrs BC) the human presence in the Alpine region was too sparse to influence the natural climate- and vegetation-driven fire regime (Carcaillet et al., 2009; Fig. 2). During this first fire epoch DAPT concentration sensu Pyne (2001), fires were ignited by lightning, as volcanoes in the Alps were already inactive, and the fire regime was characterized by long fire return intervals, e.g., 300–1000 yrs ( Tinner et al., 2005, Stähli et al., 2006 and Carcaillet et al., 2009). The shift to the second fire epoch sensu Pyne (2001) took place with the Mesolithic-Neolithic transition (6500–5500 cal. yrs BC; Fig.

2) when fire activity increased markedly throughout the Alps ( Tinner et al., 1999, Ali et al., 2005, Favilli et al., 2010, Kaltenrieder et al., 2010 and Colombaroli et al., 2013) as a consequence of an increase in the sedentary population and a corresponding use of fire for hunting and to clear vegetation for establishing settlements, pastures and crops ( Tinner et al., 2005 and Carcaillet et al., 2009). The anthropogenic signature of the second fire epoch is documented in the Alps from the Neolithic to the Iron age (5500–100 cal. yrs BC) by the positive correlation PLX3397 manufacturer between charcoal particles and peaks in pollen

types indicative of human activities ( Tinner et al., 1999, Tinner et al., 2005, Kaltenrieder et al., 2010, Berthel et al., 2012 and Colombaroli et al., 2013). Despite the anthropogenic origin, the general level of fire activity highly depended on the climate conditions. Areas on the northern slopes of the Alps experienced charcoal influx values one order of magnitude lower than the fire-prone environments of the southern slopes ( Tinner et al., 2005). Similarly, phases of cold-humid climate coincided with periods of low fire activity in these areas ( Vannière et al., 2011). In the Alps, the human approach to fire use for land management has changed continuously according to the evolution

of the population and the resources and fires set by the dominant cultures alternating in the last 2000 years (Fig. 3). Consequently, the shift from the second to the third fire epoch sensu Pyne (2001) is not definite as they have coexisted up to the present, similarly to other European regions, e.g., Seijo and Gray (2012), and differently from other areas Clostridium perfringens alpha toxin where it coincides with the advent of European colonization ( Russell-Smith et al., 2013 and Ryan et al., 2013). For example, the extensive use of fire that characterizes the second fire epoch completely changed in the Alpine areas conquered by the Romans starting at around 2000 cal. yrs BC. Under Roman control the territory and most forest resources were actively managed and also partially newly introduced (i.e., chestnut cultivation) and hence the use of fire was reduced proportionally ( Tinner et al., 1999, Conedera et al., 2004a and Favilli et al., 2010; Fig. 2). Consequently, during Roman Times, studies report a corresponding decrease in fire load throughout the Alps ( Blarquez et al.