Evaluación de parámetros poblacionales y regeneración natural de Podocarpus oleifolius D. Don (Podocarpaceae) en dos relictos boscosos del sur del Ecuador

Abstract

Populations have structure and dynamics, which are basic features used to understand the ecological processes of species. The native species Podocarpus oleifolius D. Don has ecological and economic importance at a local and national level, therefore, its populations have undergone drastic changes that have generated the formation of small forest relics. Therefore, the present investigation was in charge of studying the spatial distribution, age structure, sex ratio, population density (population parameters) and natural regeneration of Podocarpus oleifolius D. Don in two wooded relics of southern Ecuador, for which 12 plots of 50 m x 50 m were established, six located in the Angashcola communal forest reserve and six in the properties of the Arcoiris Ecological Foundation (San Francisco); in these plots, data were collected on the tree stratum of: DAP, height, sex, crown diameter, phytosanitary status, geographical coordinates; and 60 sub-plots (5 in each plot) of 10 m x 10 m to collect information on natural regeneration. To determine the spatial distribution, the standardized Morisita index (Ip) was used and contrasted with the tool: QGis close neighbor analysis; and to determine the sex ratio, the relationship between males and females was established. The information and results allowed to determine that in the communal forest Angashcola, Amaluza, the population of Podocarpus oleifolius D. Don manifested a pattern of spatial distribution grouped that resulted in a Morisita index of 0.50. The absolute density is 136 ind/ha, where the youngest individuals make up 23.70 % (sapling). 29 female and 12 male individuals were identified in proportion 2.42: 1; three categories of natural regeneration were determined: sapling, low latizal and high latizal; where the sapling category predominates with 91 individuals. The population of Podocarpus oleifolius D. Don manifested a uniform spatial distribution pattern, which resulted in a Morisita index of 1.00 in this site. The absolute density is 22.66 ind/ha, where the youngest individuals and adults represent 28.95 %; the proportion of female and male individuals is 1:1. Three categories of natural regeneration were determined: sapling, low latizal and high latizal; where high latizal predominates with 16 individuals. Therefore, it is essential to continue with related studies in this field of research applied to forest species that play an important ecological role (dominant, key or threatened) within the forest. Keywords: ecology, population parameters, Podocarpus oleifolius, natural regeneration.