Distribución, tamaño y estructura poblacional de Jubaea chilensis en “Las Palmas”, comuna de Petorca, región de Valparaíso – Chile

Chilean palms (Jubaea chilensis) are endemic of central Chile and are classified as vulnerable according to the category of conservation. Even though the population of palms has gone down, there are still some groups (palmar) that remain in locations such as Petorca, Chile. In Petorca, the site “Las Palmas” was declared “Priority Site for the Biodiversity Conservation”. However, the number of palms, their age and spatial distribution in “Las Palmas” are still unknown. Thus, in order to describe the conservation status, a population survey of palms was done. Location and age of every palm (infantile, child, adult or old, according to morphological features) were noted and their position georeferenced. Data were analyzed using a geographic information system that included maps and satellite imagery (Quickbird II). To assess the spatial distribution of palms, a Complete Spatial Randomness (CSR) test was applied using an L-function. Main results showed that 1,300 palms are present in “Las Palmas”. Among those palms, 41 % are infantile, 45 % are young, 14 % are adults and 0.5 % are old plants. Infantile, young and adult palms have an aggregated distribution in high and inaccessible areas of the watershed headwater, while old palms have disaggregated distribution. The palmar is crossed by route E-37-D, where some adult palms that produce seeds are commonly present. However, if any seed gets to infantile palm, it does not reach the juvenile stage. There is no regeneration in lowland and in the proximity of communities. Thus, the palmar is reducing its extension.