Long-term variability of Abies alba in NW Romania: implications for its conservation management

Aim Although Abies alba is not yet prioritized for conservation in many European countries, its importance is acknowledged under the EU Directive on the marketing for forest reproductive material. The Apuseni National Park contains one of the largest areas of remnant native A. alba in central eastern Europe. Here, we examine the antiquity of the present A. alba communities in the forests of NW Romania and the drivers behind their variability over the last 6000 years leading to current distribution pattern. Location The Apuseni National Park (ANP), NW Romania. Methods We use fossil pollen, microscopic and macroscopic charcoal and AMS(14)C dating on four sedimentary sites in the west-central ANP. Results The results reveal that stands of A. alba have been growing in NW Romania from at least 5700 yr BP and occurred in low abundance until 4200 yr BP. A. alba expanded thereafter and it thrived in multispecies forest stands with Fagus, Picea, Carpinus, Tilia, Quercus and Ulmus between 4200 and 1200 yr BP. The initial expansion occurred during an independently documented period of high moisture and cooler temperature as inferred from isotope data from cave stalagmites within this region. The final decline in A. alba abundance and distribution started from about 1200 yr BP and reached an unprecedently low value over the last 300 years, which was primarily caused by the increase in human activities in the region through deforestation, forest browsing and burning, and commercial forestry. Main conclusion Different management strategies ranging from restriction on harvesting and browsing need to be implemented in this region if A. alba is going to survive the forecasted decrease in precipitation and increase in temperature, which will further reduce its spatial distribution.