Structure of ages, sizes and growth in a local population of the Iberian wild pear (Cordoba, Spain)

Abstract

Arenas-Castro, S., Fernández-Haeger, J., Jordano-Barbudo, D. 2015. Structure of ages, sizes and growth in a local population of the Iberian wild pear (Cordoba, Spain). Ecosistemas 24(2): 7-14. Doi.: 10.7818/ECOS.2015.24-2.02

In recent decades, the remarkable proliferation of dendrochronological studies in Spain has contributed significantly to advancing knowledge of the structure and dynamics of forests. However, researches have focused mainly on forest species of greatest interest, to the detriment of other species which have a greater ecological interest. A paradigmatic case is the Iberian wild pear (Pyrus bourgaeana, D), a virtually unknown species from the ecological point of view, although classified as characteristic species of Mediterranean ecosystems. In order to describe the population structure of this species, through the tree-rings analysis we obtained the age and size of 122 individuals with DBH > 5 cm, located in two adjacent areas (abandoned olive grove and meadows of Oaks or dehesa) in Sierra Morena (Cordoba, Spain). The mean age of trees was ≈ 37±12 years, the oldest was 80, and the tree sizes were highly different, between 10 and 35 cm. Trunk diameter was not a good predictor of the tree-age, because even we found very striking differences in the age and trunk diameter relationship between closely spaced trees. Both age and growth-rates of trees in the abandoned olive grove were significantly higher than in the trees of the Dehesa. These differences could be related to the management history conducted in the study area during the last 50 years, because there are no negative density-dependent effects on growth-rates.