Exploring the effects of the assisted transfer of European beech ( Fagus sylvatica L.) provenances in the Romanian Carpathians

The genetic inheritance of a tree species is fully expressed in the phenotype only when its ecological requirements are accomplished. Therefore, genetic tests provide the opportunity to simulate the change in the environment and determine the most suitable site conditions for specific populations. In light of the unpredictable climate conditions resulting from rapid environmental changes, the current study investigated possible signs of adaptation and productivity of European beech in the Romanian Carpathian region. For this purpose, the tree growth and stability performances, as well as the transfer effect, were examined in 17 international beech provenances tested in two different environments for 27 years. Growth and stability performances were evaluated using tree height (Th), breast height diameter (DBH), and survival (S). In the case of the transfer analyses, the ecodistance approach was applied. According to the results, the average of S was 13% higher in the Carbunari provenance trial, and DBH was higher in the Sacele trial by 15%, while no noticeable differences were registered for Th. The best-performing provenances were those originating from similar site conditions to the Romanian test sites, and the transfer function detected the sensitivity of beech provenances to increasing temperature. The general transfer response of provenances revealed a similar performance across sites and suggested that provenances exhibited adaptation and acclimation to the test environments from Romanian Carpathians.