What is the response of Austrocedrus chilensis to the climatic variability in a rainfall gradient along the Andean Patagonia?

MARCOTTI, EUGENIA; AMOROSO, MARIANO; RADINS, MARCOS; SRUR, ANA; BONADA, ANABELA; BIANCHI, LUCAS; VILLALBA, RICARDO; BONINSEGNA, J.A.

Mendoza

Conferencia; AMERIDENDRO 2016; 2016

Laboratorio de Dendrocronología - IANIGLA - CCT CONICET Mendoza

p { margin-bottom: 0.25cm; line-height: 120%; }The populations ofAustrocedrus chilensis (ciprés de la cordillera) in the AndeanPatagonia develop along a steep altitudinal (500- 1050 m.a.s.l.) andrainfall gradient 600-2000 mm per year; which cause changes in thepopulations of the species. In order to study the climate-growthrelationship of these populations along the gradient, tree-ring widthchronologies were developed from twelve sites located along twotransects: North Transect (40°S- 71°W) and South Transect(41°S-71°W). The analysis of thegrowth-climate response of thetwelve chronologies (of about 260 years), generally presentednegative correlations with temperature and positive correlations withprecipitation. The elevated temperatures during December (growthseason) significantly correlated with a decrease in the growth of thespecies, a relationship that was observed for all of the sites. Itwas also observed that in mesic sites the high temperatures duringFebruary and March (end of austral summer), may also negativelyaffect growth. On the other hand, precipitation exhibited a positivecorrelation with growth, particularly during the months of November,December and January, resulting these the most important months forthe growth of ciprés. The sites found farthest east, which have theleast precipitation, exhibited a weak correlation with temperatureand precipitation, while the sites farthest west had a strongcorrelation on with precipitation. This could be associated to agreater response and sensibility in the growth of ciprés, when wateris a limiting resource. These studies on environmental gradients areimportant, since they allow us to understand the influence thatclimatic variables have on the species of Patagonia, which is ofvital importance since these forests will be greatly affected byexpected future climate scenarios.