Climate, fire, and vegetation between about 13,000 and 9200 14C yr BP in the Chilean lake district

A pollen record from Lago Condorito (41 degrees 45'S, 73 degrees 07'W) shows that North Patagonian Rain Forest taxa predominated between about 13,000 and 12,200 C-14 yr B.P. in the lowlands of southern Chile, near the city of Puerto Montt. This was followed by the expansion and persistence of the conifer Podocarpus nubigena between 12,200 and 9900 C-14 yr B.P. Trees favored by disturbance expanded between 11,200 and 9900 C-14 yr B.P., concurrent with sharp and sustained increases of microscopic charcoal particles. Taxa of low-elevation rain forests expanded and became more diverse in pulses centered at 9900 and 9000 C-14 yr B.P., following the disappearance of P. nubigena. These data suggest conditions approaching modern climate between about 13,000 and 12,200 C-14 yr B.P. The climate cooled between 12,200 and 9900 C-14 yr B.P., then quickly warmed to interglacial conditions. Stand-replacing fires occurred near Lago Condorito between 11,200 and 9900 C-14 yr B.P., under cool-temperate, humid conditions. The proximity and reported antiquity of the Monte Verde archeological site raise the possibility that these fires were set by human activities. (C) University of Washington.