Biomass equations are a helpful tool to estimate the tree and stand biomass production and standing stock. Such estimations are of great interest for science but also of great importance for global reports on the carbon cycle and the global climate system. Even though there are various collections and generic meta-analyses available with biomass equations for mature trees, reports on biomass equations for juvenile trees (seedlings and saplings) are mainly missing. Against the background of an increasing amount of reforestation and afforestation projects and forests in young successional stages, such equations are required. In this study we have collected data from various studies on the aboveground woody biomass of 19 common tree species growing in Europe. The aim of this paper was to calculate species-specific biomass equations for the aboveground woody biomass of single trees in dependence of root-collar-diameter (RCD), height (H) and the combination of the two (RCD2 H). Next to calculating species-specific biomass equations for the species available in the dataset, we also calculated generic biomass equations for all broadleaved species and all conifer species. The biomass equations should be a contribution to the pool of published biomass equations, whereas the novelty is here that the equations were exclusively derived for young trees

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.

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Browsing of tree saplings by deer hampers forest regeneration in mixed forests across Europe and North America. It is well known that tree species are differentially affected by deer browsing, but little is known about how different facets of diversity, such as species richness, identity, and composition, affect browsing intensity at different spatial scales. Using forest inventory data from the Hainich National Park, a mixed deciduous forest in central Germany, we applied a hierarchical approach to model the browsing probability of patches (regional scale) as well as the species‐specific proportion of saplings browsed within patches (patch scale). We found that, at the regional scale, the probability that a patch was browsed increased with certain species composition, namely with low abundance of European beech (Fagus sylvatica L.) and high abundance of European ash (Fraxinus excelsior L.), whereas at the patch scale, the proportion of saplings browsed per species was mainly determined by the species’ identity, providing a “preference ranking” of the 11 tree species under study. Interestingly, at the regional scale, species‐rich patches were more likely to be browsed; however, at the patch scale, species‐rich patches showed a lower proportion of saplings per species browsed. Presumably, diverse patches attract deer, but satisfy nutritional needs faster, such that fewer saplings need to be browsed. Some forest stand parameters, such as more open canopies, increased the browsing intensity at either scale. By showing the effects that various facets of diversity, as well as environmental parameters, exerted on browsing intensity at the regional as well as patch scale, our study advances the understanding of mammalian herbivore–plant interactions across scales. Our results also indicate which regeneration patches and species are (least) prone to browsing and show the importance of different facets of diversity for the prediction and management of browsing intensity and regeneration dynamics.