Relación entre el índice de área foliar del dosel y el crecimiento de los renovales de coihue y de ciprés de la cordillera

Abstract

Coihue and andean cypress saplings growth in relation to canopy leaf area index. The growing space occupancy by the canopy influences the development of natural regeneration. The leaf area index (LAI) is a variable that can be used in ecological studies and in silvicultural decisions process to represent the growing space occupancy in a stand. It is especially useful in mixed forests, as it is better at capturing the complexity of forest structure than other density variables. Andean cypress (Austrocedrus chilensis) and coihue (Nothofagus dombeyi) are species of forest importance of the Andean-Patagonian forests, which can grow in mixed formations with productive potential. Being able to determine which are the target structures of these forests to promote regeneration implies knowing how the canopy growing space occupancy affects the growth of advanced regeneration. The objective of this study was to evaluate the relationship between the canopy LAI and its distribution in the species and height strata with the height increment of advanced regeneration of Andean cypress and coihue. The height increment of the saplings shows an opposite tendency to the LAI of the canopy, although this relationship is significant only for coihue. For this species, the growth of the saplings is favored below a canopy LAI close to 4. In turn, the height increment, especially for coihue, is negatively influenced by a greater participation of coihue in the canopy LAI. From the results, it is inferred that, in order to stimulate the growth of the regeneration of both species, it is necessary to keep, by thinning, the LAI below 4 in the sectors where it is necessary to promote the regeneration of coihue, and above 4 to promote the Andean cypress regeneration. [Keywords: height increment, natural regeneration, growing space occupancy, LAI, Austrocedrus chilensis, Nothofagus dombeyi, mixed forest, forest management]