From breeding to landscape : how genetic improvement and forest management shape multifunctionality in Norway

Balancing wood production, biodiversity, and climate regulation is increasingly challenging for forest management, particularly as societal demands intensify. Despite growing interest in genetic improvement to enhance forest productivity, its implications for multiple ecosystem services (FES) remain poorly quantified. To address this gap, we assessed how genetically improved regeneration material, combined with alternative management regimes, influences FES provision in Norway. Using National Forest Inventory data, a climate-sensitive single-tree simulator, and multi-objective optimization, we projected 100-year outcomes under three strategies: no genetic gain, growth-focused improvement, and combined improvement in growth and wood quality. The strongest responses occurred when genetic improvement targeted both growth and wood quality. Under this scenario, harvest net value increased, ecological hotspot areas expanded, and larger set-aside areas were maintained while meeting national harvest demands. Carbon storage in harvested wood products also increased, whereas carbon sequestration in living biomass showed no consistent trend. Genetic gain reinforced positive interactions between bioenergy and climate regulation but left most other FES relationships broadly unchanged. Varying genetic gain levels produced only minor differences across most indicators, suggesting that long-term outcomes depend more on how improved material is integrated within a flexible management portfolio than on the exact magnitude of genetic gain. Positive responses in the structural biodiversity indicators should be interpreted cautiously, as these proxies capture only a limited subset of ecological dimensions and likely underestimate broader biodiversity trade-offs. Overall, genetically improved material represents a complementary tool for enhancing forest multifunctionality when integrated with adaptive, landscape-scale management.