Técnicas de enriquecimiento de bosque degradados en la Selva Paranaense de Misiones, Argentina

Abstract

Los bosques nativos degradados y los bosques secundarios en la Provincia de Misiones, Argentina superan el millón de hectáreas (33% del territorio provincial). Se presentan resultados preliminares de cuatro ensayos de enriquecimiento de bosques nativos remanentes luego del aprovechamiento. Se utilizaron fajas de enriquecimiento que incluyeron un total de once especies de importancia comercial en un establecimiento privado en San Pedro y en la Reserva Forestal Guaraní. En evaluaciones realizadas entre 4 y 7 años de edad se destacaron por su crecimiento en altura y sobrevivencia Bastardiopsis densiflora, Ocotea puberula, Enterolobium contortisiliquum, Cordia trichotoma y Peltophorum dubium. La incorporación de Euterpe edulis (palmito) en las fajas de enriquecimiento surge como una alternativa para acelerar el retorno de la inversión y hacer a esta práctica más rentable. Las técnicas de enriquecimiento y la conducción de la regeneración natural deben ser tratadas en forma simultánea para garantizar la persistencia del recurso.

Line enrichement experiments using native species of commercial value were established in overexploited forests in Misiones, Argentina, on public and private lands. Tentimber species were tested, as well as Euterpe edulis (palmito) which can be harvested after 10-12 years for its heart of palm. Fourto seven years after planting, the timber species with greatest mean height and d.b.h. were Bastardiopsis densiflora, Enterolobium contortisiliquum, Nectandra lanceolata, Ocotea puberula and Peltophorum dubium. Cordia trichotoma and Balfourodendron riedelianum both higly appreciated timber species, could also be recommended for enrichment despite their relatively slower growth. The palmE.edulis had a low survival rate but the remaining individuals showed good height and d.b.h. Labor costs associated with establishment and care of enrichment plantings were similar to other reports for the region. The incorporation of species with shorter harvest age and high economic value such as the palm E.edulis can accelerate and increase investment returns of enrichment plantings. Though long-termsresults are required to document the potential for growth and quality of production for each species, results from the experiments described in this article can provide insights to the use of these species in enrichment of overexploited and secondary forests in the region.