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Identifying and understanding the response of tree species to climate variability and drought events is a key challenge in addressing climate change in the Andean ecosystems of southern South America. This study aims to: (1) determine the main temporal patterns of radial growth of three Nothofagus species (N. pumilio, N. dombeyi, and N. alpina) on the northwest slope of the Choshuenco volcano, around 40 degrees S, (2) examine the relationship between radial growth and environmental variables, as well as climatic forcings, and (3) evaluate the resilience of these species across an altitudinal gradient in the Valdivian Andes. The chronologies of the three Nothofagus species were assessed using principal component analysis, correlation analysis between the chronologies and environmental variables, and resilience analysis for drought years. The Nothofagus chronologies reveal an increased common signal in radial tree growth since the 1980s. At the beginning of the growing season (November) all chronologies exhibit a negative relation with precipitation and some chronologies positive relations with mean air temperature and the 0 degrees C isotherm height. These findings suggest that the persistence of snow cover during spring may be crucial for the onset of the tree growth. Previous year hydroclimate appears to have an important role favoring tree growth, with most chronologies exhibiting positive relations with summer soil moisture, and circulation patterns forced by the Antarctic oscillation that favors wet mild and summers. The response to drought varies among species, with N. alpina notably exhibiting high resistance, recovery and resilience, likely due to its location near the southern limit of its distribution. Integrating analyses of temporal growth patterns, growth-environment variables relationships, and drought resilience enhances understanding of how Nothofagus species have responded to climatic variability in recent decades in the Valdivian Andes forests.

来源平台：ECOSYSTEMS