Differences in Nothofagus pumilio forest structure and tree-ring growth along altitudinal gradients at different aspect in Southern Patagonia

A. SRUR, , R. VILLALBA, M. RODRÍGUEZ CATÓN, M. MORALES, I. MUNDO, M. AMOROSO, A. RIPALTA

Tucson, Arizona

Conferencia; Second American Dendrochronology Conference; 2013

Universidad de Arizona y Tree-Ring Society

The objective of this study is to estimate the potential changes global warming will impose on the structure and growth of Nothofagus pumilio forests along elevational gradients and different aspect. Structural traits and tree-ring growth patterns were analyzed at three elevational points with different exposures. Along gradient, height and diameter decreased. Tree growth trends over the past 120 years show that low-elevation forests present a significant reduction in growth at sites facing north. Negative growth trends at low elevations are related to increasing summer temperature. Mid- and high elevation stands also showed decreasing trends in growth patterns, though the south facing in both altitudinal strips evidenced an opposite pattern linked to summer temperatures over the 20th century. The establishment of new individuals above treeline is more frequently at south forests. Whereas variations in regional climate influences both the structure and rate of growth of Nothofagus pumilio forests along elevational gradients, differences related to site conditions influences the patterns of tree growth and establishment.