Diversity and ecological importance of tree vegetation at El Tecuan Park in the state of Durango, Mexico

Abstract

Protected natural areas seek the conservation of biodiversity. The objective of this study was to describe the tree species diversity and its ecological importance in the El Tecuan Ecological Park in Durango, Mexico. A systematic stratified sampling was carried out with 168 circular sites of 1 000 m2 each, distributed in 511.16 hectares of the Park, which means a sampling intensity of 3.2 %. At each site, all individuals with a greater or equal to 7.5 cm DBH were measured. The diversity of tree species was estimated with the Shannon index, while the ecological importance of the species was described with the parameters relative abundance based on the density or number of trees per hectare, relative dominance according to the basal area, relative frequency and the value of ecological importance (VIE). Results showed the presence of four genera: Arbutus (Ericaceae), Juniperus (Cupressaceae), Pinus (Pinacea) and Quercus (Fagacea). The Shannon index was 1.89, suggesting mid to high tree species diversity. The observed growing stock was 153.73 m3 ha-1 and the dominant diameter and height classes were 10 cm and 5 m, respectively. The Pinus genus had greater richness with nine species, of which P. cooperi recorded the highest density values (32.15 %), dominance (37.77 %) and of ecological importance (28.23 %), however, Quercus sideroxyla registered the highest relative frequency (18 %). The results here described will allow the development of sustainability actions for the conservation of tree species diversity in the study area.