Recuperación estructural en bosques sucesionales andinos de Porce (Antioquia, Colombia)

Abstract

Places subjected to natural or human disturbance can recover forest through an ecological process called secondary succession. Tropical succession is affected by factors such as disturbances, distance from original forest, sur-face configuration and local climate. These factors determine the composition of species and the time trend of the succession itself. We studied succession in soils used for cattle ranching over various decades in the Porce Region of Colombia (Andean Colombian forests). A set of twenty five permanent plots was measured, includ-ing nine plots (20x50m) in primary forests and sixteen (20x25m) in secondary forests. All trees with diameter ≥1.0cm were measured. We analyzed stem density, basal area, above-ground biomass and species richness, in a successional process of ca. 43 years, and in primary forests. The secondary forests’ age was estimated in previ-ous studies, using radiocarbon dating, aerial photographs and a high-resolution satellite image analysis (7 to >43 years). In total, 1 143 and 1 766 stems were measured in primary and secondary forests, respectively. Basal area (5.7 to 85.4m2ha-1), above-ground biomass (19.1 to 1 011.5 t ha-1) and species richness (4 to 69) directly increased with site age, while steam density decreased (3 180 to 590). Diametric distributions were “J-inverted” for primary forests and even-aged size-class structures for secondary forests. Three species of palms were abun-dant and exclusive in old secondary forests and primary forests: Oenocarpus mapora, Euterpe precatoria and Oenocarpus bataua. These palms happened in cohorts after forest disturbances. Secondary forest structure was 40% in more than 43 years of forest succession and indicate that many factors are interacting and affecting the forests succession in the area (e.g. agriculture, cattle ranching, mining, etc.).