2004).Ĭanopy opening, both in natural conditions or under human-induced disturbances, changes the availability of indispensable resources and/or create new microsites that allowed the establishment and growth of seedlings (Christie and Armesto 2003 Bailey et al. In these forests, abundant seedling establishment occurs after harvesting mainly from pre-existing regeneration (Gea et al. The rationale of the silvicultural practices is based on the natural forest gap dynamics, where seedling establishment, growth, and yield are enhanced (Messier et al. 2015), and nutrient availability (Burgess and Wetzel 2000 Catovsky and Bazzaz 2002). Harvesting of Nothofagus forests in southern Patagonia is mainly based on canopy opening to enhance recruitment and seedlings growth by modifying light, soil moisture (Caldentey et al. It is necessary to develop new silvicultural practices that decrease the unfavorable microenvironments (e.g., road density or excessive woody accumulation), to assure the success of the proposed silvicultural method. Conclusionsįavorable microenvironments in the harvested areas will improve the natural recruitment, growth, and eco-physiology performance of the natural regeneration after harvesting. The most unfavorable microenvironment conditions were high canopy cover of remnant trees (inside the aggregates or close to trees in the dispersed retention) and heavily impacted areas (skidder extraction roads). Seedling under debris and dicot plants showed better eco-physiological performance, establishment, and growth than plants growing under monocots or located in the dispersed retention without the protection of other understory plants. Microenvironments offered different environmental conditions for natural regeneration (soil moisture and light availability). Univariate and multivariate analyses were conducted for the comparisons. We characterized the seedling bank, as well as growth and ecophysiology performance of the regeneration. Remnant forest structure after harvesting and different microenvironments were characterized in managed stands, where 105 regeneration plots were measured (3 stands × 7 microenvironments × 5 replicas). This study evaluated the regeneration in different microenvironment conditions within managed stands during 5 years after harvesting.
Harvesting by opening canopy generates different microenvironments and creates contrasting conditions for seedling establishment, growth, and eco-physiology performance due to synergies (positives or negatives) with biotic and abiotic factors.
Variable retention (aggregated and dispersed retention) harvesting proposed for Nothofagus pumilio was designed for timber purposes and biodiversity conservation.