Revista chilena de historia natural
versión impresa ISSN 0716-078X
SALDANA, ALFREDO y LUSK, CHRISTOPHER H.. Influence of overstorey species identity on resource availability and variation in composition of advanced regeneration in a temperate rainforest in southern Chile. Rev. chil. hist. nat. [online]. 2003, vol.76, n.4, pp. 639-650. ISSN 0716-078X. http://dx.doi.org/10.4067/S0716-078X2003000400008.
Understory habitat heterogeneity is a factor promoting maintenance of species diversity in forest communities. The influence of over storey species identity on resource availability and variation in composition of advanced regeneration was studied in a temperate rain forest in southern Chile. The forest over storey was dominated by the broadleaved evergreens Laureliopsis philippiana, Aextoxicon punctatum, Eucryphia cordifolia and Nothofagus dombeyi. Availabilities of diffuse light, nitrogen, phosphorous and calcium were measured under these four over storey species, as was nutrient content of leaf litter. Advanced regeneration was sampled in plots beneath each over storey species, and results analyzed by ordination. There were significant differences in light transmission, nutritional content of leaf litter and availability of N-NO3 and P beneath the four species. Nevertheless, all nutrients showed low availability due to low mineralization and high immobilization. Ordination results indicate that the composition of advanced regeneration under N. dombeyi and L. philippiana differed from the composition of regeneration under A. punctatum or E. cordifolia. The ordination suggested that light level explained a large proportion of compositional variation. We propose that species regenerating in the understory differed more in shade tolerance than in nutritional requirements, being the light the most limiting resource in the under story
Palabras llave : evergreen forest; advanced growth composition; mineralization; light gradient.