The north-eastern distribution range of European beech a review

Today, European beech (Fagus sylvatica L.) seems to be a markedlysuccessful tree species in the north-east of its distributionrange. The distribution area may be larger than originally assumed;past forest management is probably the main cause of the contractionin the postglacial European beech range. Numerous attempts consistentlyhave failed to locate a distinct distribution edge for Europeanbeech. Therefore, we define northern and eastern Poland andthe southern regions of the Baltic States as margins of Europeanbeech distribution. Ecophysiological approaches have identifiedthe drought constraints for European beech in terms of (1) thecritical limit for xylem cavitation and loss of hydraulic conductivity,reached at a shoot water potential of –1.9 MPa, and (2)a reduction in gross primary production and total ecosystemrespiration when relative extractable soil water reaches 40and 20 per cent, respectively. However, it is difficult to correlateEuropean beech distribution margins with single macro-climaticfactors. Moreover, the adaptation of European beech populationsand provenances to drought and frost varies. The phenotypicplasticity and evolutionary adaptability of European beech appearto be underestimated. These characteristics may counteract afurther contraction of the European beech range arising fromclimate change in the future.