Impact of Thinning on Sexual Symmetry and Gene Diversity in Pinus brutia Ten. Plantation

Thinning is widely used in the context of sustainable forestry, but its impact on the gene diversity of the next generation remains unclear. In this study, we evaluated some commonly proposed genetic parameters for managing gene diversity in seed orchards. In this framework, we checked whether sexual symmetry, fecundity variation, and linked metrics (i.e., effective population size and gene diversity) can be used to optimize gene diversity through thinning in production forests. We divided trees in a Brutia pine plantation in southern Türkiye into three different canopy cover classes: the control group, the moderately thinned group, and the heavily thinned group, and monitored them. The results of our research revealed the impact of thinning on genetic parameters and showed that these metrics can be used to manage gene diversity in production forests. We believe that this study can function as a prototype for future studies using different thinning intensities in various regions and for different species to determine the most appropriate thinning intensities for sustainability.