Temporal Dynamics and size effects of Mistletoe (Loranthus europaeus Jacq.) Infection in an Oak Forest

摘要

Establishing a better understanding of changes in mistletoe abundance over time could prove useful in the development of future conservation and management strategies for mistletoe-host complexes. The purpose of this study was to describe and examinehow time influenced host trees sessile oak (Quercus petraea (Matt) Liebl.) and the abundance dynamics of their hemiparasites yellow mistletoe (Loranthus europaeus Jacq.). The research was conducted in Podyji National Park, Czech Republic, from 2011-2015.Each oak stem (1599) was visually checked for the presence of he-miparasites during the bud growth period. We investigated the temporal dynamics of L. europaeus abundance (number of L. europaeus shrubs per Q. petraea stem) and volume (total volume of L. europaeus shrubs per stem) on individual host stems using linearmixed effects models. The abundance of L. europaeus increased with larger host diameter at breast height (DBH), time and their interaction. The abundance of L. europaeus slightly increased over time on hosts with smaller DBH, but this phenomenon slowed down as host DBH increased. Mistletoe abundance started decreasing over time on hosts with large DBH. The study showed that time plays an important role in determining the distribution of mistletoes in the stand. Thanks to the inclusion of the time component, it was possible to create a model that showed the most vulnerable groups of host trees to which forest management should focus on.