Producción de restos vegetales y descomposición de hojarasca foliar bajo distintas intensidades de corta en fajas en matorrales

Abstract

Biomass extraction in native forests can induce changes in the functioning of these ecosystems; these changes are poorly studied, and this represents a knowledge gap. In this work, we evaluated the response of plant litter production and decomposition to increasing intensities of strip cutting in native scrublands. We set an experiment replicated in three sites: hillside with southern exposure (FS), hillside with northern exposure (FN) and valley bottom (R), with four intensities of strip cutting (0, 30, 50, and 70% of the area). To evaluate decomposition, we used bags filled with ñire leaves (Nothofagus antarctica), and for the production of litter, plastic mesh collectors. In addition, vegetation height and cover were measured. In the three sites, we observed the same temporal pattern of decomposition, with a marked decrease in organic matter during the coldest period of the year. The effects of cutting intensity were strongly influenced by the site: at FS, litter production increased, but there was no effect on decomposition; in contrast, at FN and R, production decreased and a curvilinear pattern was observed, with highest decomposition at intermediate harvest intensity. Aerial over was positively correlated with production, and this, in turn, negatively correlated with decomposition. Our results suggest that in scrublands with high vegetation cover, strip cutting could promote litter production without affecting decomposition. In contrast, less productive sites with lower vegetation cover would be more sensitive to forestry interventions.