EARLY DEVELOPMENT OF NOTHOFAGUS (NOTHOFAGACEAE) SPECIES FROM THE SUBANTARCTIC FOREST UNDER EXPERIMENTAL CONDITIONS OF LIGHT, SUBSTRATE AND ECOLOGICAL INTERACTION

ABSTRACT The entry of trees into a community is an irregular process often constrained by species interactions and regeneration niche. We experimentally examined the effect of light intensity (high, medium and low), substrate type (mineral and cover with litter) and presence of Chusquea culeou (Poaceae), on the performance of regeneration of Nothofagus dombeyi, N. obliqua and N. alpina (Nothofagaceae). These species constitute the natural forest within the lake Lácar watershed (40° 08´ W, 71° 30´ S). Populations of C. culeou, an abundant understorey component that restrict tree regeneration, experimented in 2001 a gregarious fl owering and subsequent mortality comprising 200,000 ha and the development of an abundant seedlings cohort. During tests, Nothofagus species exhibited a very low germination (