Research trends : Forest ownership in multiple perspectives

The work on this article was supported by COST (European Cooperation in Science and Technology) in the framework of the COST Action FP1201 - Forest Land Ownership Changes in Europe: Significance for Management and Policy (FACESMAP). In addition, the authors want to acknowledge all participants of the COST Action for their contributions throughout the Action as well as the very valuable peer reviewer comments.Peer reviewedPostprin

Dispersal and larval hosts of the zigzag sawfly Aproceros leucopoda (Hymenoptera) in Slovakia, Central Europe

Background and purposeThe zigzag elm sawfly, Aproceros leucopoda (Hymenoptera), originating from Asia is being considered as one of the major pests of elm trees (Ulmus spp.) within Europe where it was first recorded in 2003. Recent investigations document the fast spread of this invasive species in many European countries. In Slovakia, A. leucopoda was first recorded in 2009 but its occurrence here has not been reported since 2009. Herein, we summarize the data from the two consecutive years about the current distribution of A. leucopoda and its hosts in Slovakia, Central Europe, focusing on infestation of elm trees by this successful invader in different altitudes.Material and methodsIn 2014 and 2015 the investigations of A. leucopoda were conducted at 101 different plots across the country. At each plot, characteristic symptoms of leaf damage, occurrence of larvae, cocoons or adults were recorded along with the geographical coordinates and the altitude, and the host trees of A. leucopoda were identified at the species level. The distribution map of A. leucopoda was drawn using the field data. The infestation of elm trees along the altitudinal gradient was analyzed with Kruskal-Wallis non-parametric analysis of variance followed by post-hoc Dunn\u27s test for multiple comparisons.Results and conclusionsThe zigzag elm sawfly A. leucopoda was observed at 31 plots (30.7%, n = 101). In elm trees examined, generally, a low level of infestation by this pest was observed. A. leucopoda was found at plots between 107 and 701 m a.s.l. The result show that the infestation level of elm trees was decreasing with increasing altitude. Although we had only a small sample of data, we assume that the altitude has a significant effect on distribution of this pest. The field elm (Ulmus minor Mill.) was the most frequently utilized host. Data collected document the establishment of this successful invader in Slovakia.</p

Reakcia dubov voči klimatickým extrémom v prechodnej zóne dubových a bukových lesov

Forest management might be threatened by declining health status of oaks in the transition zone between oak and beech forests, where drought is the most limiting factor. The aim of the presented paper is to assess the influence of selected climatic characteristics on the radial growth of oak trees with different stem diameter status in the beech-oak and oak-beech forest altitudinal zones within the forest growth area of Poľana Mt. and Zvolen Basin (Slovakia). Our results show that oaks with less favourable stem diameter position (Weisse’s middle stems) show slower radial growth, have less pronounced climatic precipitation signal and milder response to extreme climatic events. The findings potentially suggest that not only favourable tree species composition of stands, but also the stand structure can mitigate the negative impacts of climate change on forest growth.peerReviewe

Forest ownership changes in Europe: State of knowledge and conceptual foundations

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