Forty years of silvicultural management in southern Nothofagus pumilio (Poepp. et Endl.) Krasser primary forests.

G GEA IZQUIERDO; G MARTÍNEZ PASTUR; JM CELLINI; MV LENCINAS

FOREST ECOLOGY AND MANAGEMENT

Elsevier

Año: 2004 vol. 201 p. 335 - 347

0378-1127

To achieve sustainability of a forest system it is necessary to apply an appropriate silvicultural management including preservation issues. The characterization of the status and development of the harvested stands, as well as the timber potential of the unmanaged ones, is necessary to achieve a sustainable forest management. Southern Patagonian Nothofagus forests are the basis for the sawmill industry. Since the European colonization, different silvicultural management regimes have been applied over the primary forests. Forest policies and available sawmill technologies have also involved. There is little knowledge about the consequences derived from the different silvicultural systems implemented as well as about the regeneration status of the harvested stands and future possibilities of the managed forests. The objective of this work was to analyse the felled, affected from harvesting and current forest structures, as well as the regeneration development during the last forty years and the consequences derived to forests of southern Patagonia. The harvesting was applied irregularly along the studied decades (30 15% of the original basal area was removed) originating an irregular forest structure. Large quantities of sawn logs were abandoned in the forest floor and a great percentage of the remaining forest structure was damaged during the harvesting. Negligent management and wind throw produced a large waste of timber, resulting in a scarce standing log volume of very low quality. Nevertheless, the regeneration was successfully installed (222 185 thousands/ha) within the harvested stands. No differences in the harvesting intensity were found with the different theoretical silvicultural methods applied through the years (selective cuts, clear-cuts or shelterwood cuts). As a result, the forests present a low current and future economical potential. Hence, the status of the secondary forest must be improved and regulated in order to achieve sustainability. Otherwise, the local forest industry will suffer from negative consequences and this valuable resource will not be profitable in the future.