Descripción: Increased forest ecosystem vulnerability is reflected in more widespread and severe drought-induced decline episodes in the last . Dominant tree species of the sclerophyllous forest in central Chile are reported to be highly susceible to loss in tree vitality, and mother trees (seed source) are experiencing extensive decline along natural areas in central Chile. The increasing mortality and browning have significantly impacted functionality and structure. However, in the wake of the so-called sclerophyllous forest collapse, attention to the reproduction process and seed quality has been practically absent. This situation highlights a gap between the theories supporting adaive silvicultural management approaches and the empirical knowledge of their outcomes. Adaive silvicultural management has the potential to counteract the decline in reproductive capacity (fruit and seed production) and support physiological processes that regulate seed dormancy and germination mechanisms. This can enhance forest resilience against persistent drought-induced disturbances in central Chile. In this context, we address the following research questions How do varying forest trajectories in response to severe drought events (megadrought) impact the availability and quality of seeds and seedlings? Additionally, how does silvicultural management---specifically, adjustments in shoot thinning and nutrition---contribute to the recovery of seed production capacity and improve the quality of seeds and seedlings? To address these questions, we hypothesize that the crown biomass balance and the nutritional status of the mother tree in sclerophyllous forest species influence the legacy effects of megadrought on production and seed quality. We therefore predicted that intensified silvicultural management practices (shoot thinning and nutrition) would increase seed production and enhance the quality attributes of seeds and seedlings in drought-affected trees compared to unmanaged (control) trees. The main objective of this proposal is to evaluate the impact of shoot thinning and tree nutrition on the production and quality of seeds and seedlings in sclerophyllous tree species, considering different recovery trajectories of drought-affected areas. To address this, we will conduct a experiment on adult seed trees under different recovery trajectories (resistance and resilient) in sclerophyllous forests affected by drought to study reproductive phenology traits and seedling quality. We will set three permanent field plots of 100 × 100 m for each of ten selected mother trees. These plots will provide a base data field of seeds production as well as species diversity, abundance, basal area, canopy cover, environmental conditions, tree mortality, recruitment and replacement, and specific functional traits related to forest resilience to drought. Three silvicultural management level will be applied for each trajectory shoot thinning, tree fertilization, and a control (no management). Shoot thinning treatment will involve removing util 50% of shoots with below-average diameter and those completely dry or dead while retaining biomass for future reproductive development, expecting some improvements for residual stems (i.e. increments in diameter growth and seed production and a reduction in mortality). Tree fertilization treatment will involve the application of 224 kg/ha of elemental nitrogen and 28 kg/ha of phosphorus around the stem of the mother trees. It is expected to monitor and quantify seed production by ecosystem trajectory during the three years of the project (2026-2027, 2027-2028, and 2028-2029). The natural laboratory of the sclerophyllous forest in central Chile affected by the latest drought events (2010-2023) offers an exceional opportunity to improve our understanding of the impacts on the reproductive phenology of seed trees and the availability and quality of these and how the silvicultural management at the individual level (mother tree) it is possible to impact the vigor of the plant and counteract the decline of the reproductive processes of mother trees. Finally, this research will improve information about seed availability in sclerophyllous forests by identifying the most efficient interventions for supporting the supply chain of propagation material (seeds and seedlings) to support resilient and climate-smart restoration.
