Fire history in the Araucaria forests of Argentina: human and climate influences

MUNDO, I.A.; KITZBERGER, T.; ROIG JUÑENT, F.A.; VILLALBA, R.; BARRERA, M.D.

Tucson

Conferencia; Second American Dendrochronology Conference; 2013

Laboratory of Tree-Ring Research - University of Arizona

Little is known about drivers and trends of historic fire regimes in the Araucaria araucana forests of southwestern Argentina. Fire history in these forests was reconstructed by the analysis of 246 fire-scarred partial cross-sections collected at 10 sites in northern Patagonia. Fire chronologies showed an increase in fire occurrence during the nineteenth century and a sharp decrease since the early twentieth century. The creation of Lanín National Park in 1937, changes in human activities, and the active suppression of wildfires led to a significant increase in mean fire intervals since 1930. Interannual variability in wildfire activity was associated with ENSO. Years of widespread fire are related to negative departures of both Niño 3.4 and PDO indices, as well as coincident phases of positive Southern Annular Mode and La Niña events. Temporal variations in Araucaria fire history in Argentina show the combined effect of human and climate influences.