Application of technologies to improve Nothofagus pumilio restoration in Chilean . Eduardo Arellano, Pontificia Universidad Católica de , Chile.

Additional Authors: Patricio Valenzuela, Pablo Becerra

Throughout history Patagonian forests have been converted to other land uses such as grazing and mining. Surface coal mining in Chilean Patagonian region results in forest and grassland disturbance, altering the landscape and affecting sensitive vegetation naturally adapted to grow in extreme site conditions. Previous reclamation experiences have been focuses on restoring grassland using exotic herbaceous species. There are no local experiences on restoring native Nothofagus forest due to poor reforestation practices that not consider seedling sensibility to soil moisture stress and windy conditions that normally end in high seedling mortality. Using the forest reclamation approach model, we previously identified microsite conditions that promote natural regeneration. Despite the high landscape variability, natural forest regeneration occurs on microsite condition where shrubs and native grasses protect the seedling. Our objective was to explore which biotic and abiotic factors favor Nothofagus pumilio reforestation following anthropic disturbance.

The study have been conducted in in Chilean Patagonia, 130 Km north from , in the . The climate is an oceanic climate bordering on a tundra climate. The seasonal temperature is greatly moderated by its proximity to the ocean, with average lows in July near −1 °C and highs in January of 14 °C, the average precipitation is 450 mm. We conducted a randomized split plot experiment to examine the effects of woody debris, shrubs, and shelters on seedlings growth, and survival during first year following planting in a mined site where top soil was replace and in grassland. We found that dark shelter; woody debris protection, and shrubs significantly increase seedling survival compared to unprotected and white shelter treatments. Radiation was 40%, 22,3%, and 30% in the white shelter, woody debris protection, and dark shelter respectively. Differences where more extreme in the treatments growing in grassland, where competition and soil moisture content stress conditions are greater tan the reclaimed site. Seedling growth was significantly greater in the reclaimed site in comparison to the grassland. Plant moisture stress analysis measurements indicate that seedling protections increase the potential for seedling growth and survival. Our results indicate that moisture stress and light saturation affect seedling performance, and any reforestation effort should consider seedling protection.