Características demográficas de una población de Nothofagus obliqua (Mirb.) blume var.macrocarpa DC. en el cerro El Roble (33° Lat. sur) en Chile

Abstract

The age structure is determined for a geographically isolated population of Nothofagus obliqua (MIRB.) BLUME var. macrocarpa DC. on cerro El Roble (33° latitude S), near the northern distribution limit in central Chile on the basis of tree ring analysis and extrapolation from curves relating number of annual rings and radius at DBH. Growth is faster on W-SW slopes and at lower altitudes. The population containts few individuals less than 25 years old and a complete absence of seedlings. Age distribution is cyclic with maxima at intervals of approximately 25 years. The application of HETT & LOUCKS (1976) power function population model suggests that the population might be in a state of decline. Results are discussed in relation to climatic features of the area, human intervention and periodic flowering pattems.