No abstract

L., Teodosiu M., 2014. Ungulate browsing causes species loss in deciduous forests independent of community dynamics and silvicultural management in Central and Southeastern Europe. Ann. For. Res. 57(2): 267-288, 2014.Abstract. Grid-based inventories of 1,924 deciduous forests plots in Germany and 4,775 in Romania were used to investigate tree species composition as affected by browsing and grazing under different forest management (rotation forestry, selectively cut forest, protected forest). At regional scale, the loss of tree species in the dominant layer was between 52 to 67% in Germany and of 10 to 30% in Romania, with largest effects in protected nature reserves in Germany. At plot level, only 50% (Germany) to 54% (Romania) of canopy species were found in the regeneration layer with a height of 1.5 m. Browsing was influenced by the proportion of Fagus in the regenerating trees in Germany, and by stand density, basal area, and management in both regions. Structural equation modeling explained 11 to 26% of the variance in species loss based on the fresh loss of the terminal bud in the winter prior to the inventory work (one season browsing). Browsing (and grazing in Romania) is shown to be a significant cause of species loss across both countries and all management types. Potential cascading effects on other organisms of deciduous forest ecosystems are discussed. We conclude that the present hunting practices that support overabundant ungulate populations constitute a major threat to the biodiversity of deciduous forests in Germany and Romania and to other places with similar ungulate management, and that changes my only be possible by modernizing the legal framework of hunting.

Earthworms have a significant influence on the structure, composition and functioning of forest ecosystems, but in spite of their role as ecosystem engineers, little is known on the factors controlling their distribution across European forests. Optimised sampling techniques, as well as more advanced statistical tools and geographical information systems have facilitated studies at the landscape scale. But these, and even larger-scale studies, are scarce due to data limitations, taxonomic inconsistencies and practical issues in linking existing databases. In this continental-scale field-based study we used boosted regression tree modelling to identify and evaluate the relative importance of environmental factors explaining earthworm incidence (presence/absence) and abundance (density and biomass) in European forests. To parameterise our models earthworms were sampled in six forest landscapes along a latitudinal gradient from the boreal north to the Mediterranean south in spring or autumn of 2012, together with several environmental variables. Earthworms were sampled using a combined method of mustard extraction and hand sorting of litter and a soil monolith, after which they were weighed and identified to functional group (epigeic, endogeic and anecic). We found that litter- and soil-related variables best explained earthworm incidence and biomass in European forests, leaving only a minor role to climate-related variables. Among the litter related variables, understory vegetation played an important role in explaining earthworm incidence and abundance. The relative importance of explanatory variables differed between models for incidence, density and biomass and between earthworm functional groups. Our results suggested that threshold values for soil C:N ratio, forest floor pH and understory plant biomass and plant nutrient concentrations have to be attained before earthworms can occur. Beyond these threshold values, variables like soil C:N ratio, tree litter C:P ratio and forest floor mass further explain earthworm biomass. Mechanisms behind these observations are discussed in the light of future earthworm distribution modelling at continental scale.Additional co-authors: Karsten Raulund-Rasmussen, Federico Selvi, Fernando Valladares, Koenraad Van Meerbeek, Kris Verheyen, Lars Vesterdal, Bart Muy

The present phylogeographic pattern of red deer in Eurasia is not only a result of the contraction of their distribution range into glacial refugia and postglacial expansion, but probably also an effect of replacement of some red deer s.l. mtDNA lineages by others during the last 50 000 years. To better recognize this process, we analysed 501 sequences of mtDNA cytochrome b, including 194 ancient and 75 contemporary samples newly obtained for this study. The inclusion of 161 radiocarbon-dated samples enabled us to study the phylogeny in a temporal context and conduct divergence-time estimation and molecular dating. Depending on methodology, our estimate of divergence between Cervus elaphus and Cervus canadensis varied considerably (370 000 or 1.37 million years BP, respectively). The divergence times of genetic lineages and haplogroups corresponded to large environmental changes associated with stadials and interstadials of the Late Pleistocene. Due to the climatic oscillations, the distribution of C. elaphus and C. canadensis fluctuated in north–south and east–west directions. Some haplotypes dated to pre-Last Glacial Maximum periods were not detected afterwards, representing possibly extinct populations. We indicated with a high probability the presence of red deer sensu lato in south-eastern Europe and western Asia during the Last Glacial Maximum.

Climate fluctuations during the Last Glacial Period between 115,000 and 11,500 years ago (Lokrantz & Sohlenius, 2006) played an important role in shaping the current species composition, distribution, and genetic diversity of mammals in Europe. During glaciations, the ranges of cold sensitive species were limited to refugial areas located in the Balkan, the Iberian and the Apennine Peninsulas (Hewitt, 2004;Taberlet et al., 1998) and south-eastern part of the continent (the Black Sea region and the Caucasus Mts.; Markova & Puzachenko, 2019). Contribution of a given refugium into postglacial recolonization processes varied a lot among species such as, for example, red deer Cervus elaphus (Niedziałkowska, Doan, et al., 2021), wild boar Sus scrofa (Niedziałkowska, Tarnowska, et al., 2021), or common vole Microtus arvalis (Stojak et al., 2015). Cold-adapted species such as, for example, reindeer Rangifer tarandus (Sommer et al., 2014), saiga antelope Saiga tatarica (Nadachowski et al., 2016), or arctic fox Alopex lagopus (Dalén et al., 2007), thrived in the glacial stages, expanded their ranges southward, and during the onset of interglacial they underwent massive, large-scale extinctions. Species of mammals that have very broad biogeographic niche (from the Mediterranean to the boreal zone) had more diverse response to geological time-scale pulsation of climate, most likely with several glacial refugia located at both lower and higher latitudes, where subpopulations diverged into different lineages and could have developed adaptations to different climate, habitat, and food-related conditions. Examples of such species include the bank vole Clethrionomys glareolus (Tarnowska et al.,