Impact of contrasting silvicultural strategies on broadleaved forest regeneration under various levels of ungulate pressure and changing climate

Temperate forests cover about 20% of the global forest area and play key ecological and economic roles. In Western Europe, forests dominated by Fagus sylvatica and Quercus spp. are particularly vulnerable to global change, while increasing ungulate densities exert additional pressure on regeneration and long-term sustainability. Promoting diversification in species composition and stand structure is often considered a promising strategy to enhance forest adaptability, yet its economic implications remain uncertain.We used the tree-level, process-based HETEROFOR model to simulate forest dynamics over 120 years across six representative stands in Western Europe, under three climate scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0), four levels of browsing pressure, and three contrasting silvicultural strategies representing conventional even-aged management, and management with moderate diversification or strong diversification efforts. Forest performance was assessed using 32 indicators summarized into six dimensions: productivity, profitability, sustainability, carbon, species diversity, and structural diversity.Our results show that diversification strategies strongly enhanced species diversity while maintaining sustainability. They provided balanced ecological and economic outcomes under low to moderate browsing pressure, whereas conventional management was the least sensitive to browsing but delivered the lowest species diversity. Under high browsing intensity, however, diversification-oriented strategies lost much of their advantage, with marked declines in productivity, carbon, sustainability, and both species and structural diversity.These findings highlight key trade-offs between productivity, diversity, and economic viability and emphasize the importance of integrating wildlife regulation into adaptive silvicultural planning. Overall, this study provides an operational framework combining ecological and economic indicators to guide sustainable forest management under global change.