Influencia del paisaje en las cortas de protección en bosques de Nothofagus pumilio: Cambios en la estructura forestal y respuesta de la regeneración.

D PAREDES; JM CELLINI; MV LENCINAS; M PARODI; D QUIROZ; J OJEDA; S FARINA; YM ROSAS; G MARTÍNEZ PASTUR

BOSQUE (VALDIVIA)

UNIV AUSTRAL CHILE

Lugar: Valdivia; Año: 2020 vol. 41 p. 55 - 64

0304-8799

During the last thirty years, shelterwood cuts has been the most applied regeneration method in Nothofagus pumilio (lenga) forests.This treatment was implemented without any consideration of the landscape, and without considering yield gradients (e.g. stand sitequalities), environmental restrictions (e.g. soil water availability) or potential natural disturbance factors (e.g. wind exposure). Theobjective was to evaluate the dynamics of the remnant forest structure and the natural regeneration 10 years after harvesting acrossthe landscape considering different environmental gradients. Sampling plots were established in nine stands distributed across Tierradel Fuego, Argentina (north, east and south areas) where forestry activity has been concentrated during the last years. The selectedareas presented differences in the rainfall regime (402 to 446 mm yr-1) and site qualities of the stands (2.6 to 3.3). Forest structure wassimilar among the studied areas, nevertheless harvesting intensity was variable (30 % to 57 %) generating different remnant basalareas (BA) (22 to 47 m² ha-1) and woody debris accumulation in the forest floor (167 to 230 m³ ha-1) after harvesting, or in combinationwith local wind-throws. The current forest structure presented differences in BA (6 to 34 m² ha-1) and established regeneration (49 to110 thousand ha-1) that varied in height (0.6 to 1.0 m) and growth (4.1 to 12.8 cm yr-1) according to the area and the received damagedue to abiotic and biotic factors. We can conclude that forests located along the considered landscapes and environmental gradientsdifferentially responded to the proposed silvicultural treatments, where climate influenced over the post-harvest canopy stability andthe established regeneration. For this, it is mandatory to define different silvicultural strategies throughout the landscape.