Leaf Growth Dynamics of Nothofagus Species Dominant in the Foothills of the Andes

Abstract

The leaf growth dynamics of three species of trees belonging to the Nothofagus genus, which together dominate temperate and subantarctic forests in Chile, were studied. It was shown that each species possesses its own characteristic leaf area growth curve, which is determined by the particular moment the buds open, total leaf area, and biomass reached at the end of the growing season, as well as total leaf area growth rate. The deciduous species, N alpina and N obliqua, initiated growth at the beginning of spring (daily mean temperature of 100C), while the evergreen species, N. dombeyi, commenced its growth two months later (daily mean temperature of 13C). The three species grew fastest during the first four weeks of the growing season. As a result, total leaf area reached its peak, in all three species, within four weeks of growth. Nevertheless, there were marked differences with respect to their final productivity values, measured as total leaf area attained as well as final total leaf biomass. N alpina had the greatest final total leaf area (30.6 cm2/ shoot) and biomass (0.2 g/shoot), while N dombeyi the smallest (5.7 cm2/shoot and 0.06 g/shoot). Leaf development data in Chilean Nothofagus species are useful both for understanding the ecology of these species and potentially for their management.