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Abstract: Despite being major drivers of the dynamics and diversity of plant populations and communities, the spatial variability of phyllosphere fungal assemblages has been seldom explored. We used CE-SSCP and 454 pyrosequencing to quantify the spatial variability of European beech phyllosphere fungal assemblages with a hierarchical sampling design including four different spatial scales (tree, branch, group of leaves and individual leaf). Fungal assemblages were highly diverse, with high proportions of generalist and cosmopolitan fungi. The major part of the variability was at the smallest spatial scale, between individual leaves. Within a single tree canopy, dissimilarity between fungal assemblages generally increased with distance between leaves. This pattern may be driven by within-canopy gradients of leaf traits and microclimate. At the stand scale, dissimilarity between fungal assemblages was correlated with the genetic distance rather than the geographic distance between trees, consistent with the findings of community genetics studies. Our results were constant over a small simulated sequencing depth, providing opportunities for the design of large-scale studies addressing the relationship between the genetic variation of trees and the variation of associated phyllosphere fungal assemblages. [Copyright &y& Elsevier] more...

Abstract: Beech trees occur in significantly lower latitudes in continental East Asia than in Europe and North America. They are common deciduous trees in the deciduous forests of the temperate zone in Europe, the eastern part of North America and Japan. In continental East Asia, however, they are absent in the deciduous forests of the temperate zone, but occur in the forests of mountains in the moist subtropical zone, south of 34° Northern Latitude. The lower limits of their distribution in these mountains show a significantly different pattern from the usual distribution pattern of plants and vegetation: it declines as the latitude decreases. The altitudinal belts of beech species lie higher in the northern than in the southern parts of their distribution areas in China. Based on an analysis of the climate and the phenology of these deciduous trees, we show that the prevailing monsoon conditions are the main factor affecting the distribution of the Chinese beech species. [Copyright &y& Elsevier] more...

Abstract: This review describes key regeneration characteristics of the genus Fagus as represented by its four most prominent species: F. crenata (F.c.), F. grandifolia (F.g.), F. orientalis (F.o.) and F. sylvatica (F.s.). Similarities and differences in the relevant life phases of these species are identified. Those are related to natural disturbance regimes and synecological peculiarities of the forests where they grow, thereby establishing a basis for evaluating the likely outcome of different silvicultural measures. Common ecological characteristics of these Fagus species’ life cycles include the masting phenomenon, pollen dispersal with effective distances of about 100m, seed dispersal to about 20m, seedling sensitivity to frost, drought, and animal predation, and a very shade tolerant establishment phase. This commonality suggests its appropriateness as a “model-genus”. However, some species also have unique ecological characteristics not observed in the others. F.g. exhibits root suckering, and beech bark disease seems to trigger vegetative regeneration by that means. Likewise, its masting behaviour deviates from F.s. F.o. and F.c., occurring more frequently and more regularly. In F.c. forests, dwarf bamboo species and their ecological characteristics are important determinants of tree regeneration establishment. The small canopy gaps that commonly occur in Fagus dominated natural forests fit very well with the genus’ regeneration characteristics. These conditions are best duplicated by management measures, which maintain partial overstory shading until the seedlings are large enough for release. However, such a strategy reduces chances to regenerate more light-demanding associated species. Together with differences in landowner objectives, the diversity of ecological conditions within and between the species of Fagus requires site-specific prescriptions to insure regeneration success, e.g. cutting regimes. Of particular interest to research are the challenges of managing mixed-species stands for high quality timber production in Central European and Caspian beech forests, the decline of F.g. and how to deal with the aftermath forest, and effective ways to manage F.c. in coexistence with dwarf bamboo. Further, the historic dispersal of heavy seeded Fagus species over long distances is still poorly understood. In addition, since their drought sensitive seedlings may be damaged or killed during extreme weather, research must address the possible effects of global climate change on the regeneration potential of beech forests. Species-bridging research may be needed to address these questions. [Copyright &y& Elsevier] more...

Abstract: Forests and forestry in Sweden are dominated by conifers. Silviculture using mixed or broadleaved stands is often recommended, but the degree to which broadleaves regenerate naturally needs to be clarified. The Swedish National Forest Inventory is here used for a region-wide study of broadleaved saplings (1.3m tall to 4.9cmdbh) regenerated naturally. For 12 species (taxa) in young forests (<7m tall) and high forests (≥7m), sapling densities were related to seven forest types and three productivity classes. Birch had highest densities in all but two broadleaved forest types. Birch, oak, rowan and sallow had 70–85% of their total sapling populations in conifer-dominated forest types, indicating good potential for mixed stands. Beech, lime, hornbeam, ash and elm were mostly restricted to ‘noble’ (hardwood) forests. The regeneration success (saplings per mature tree) for birch, rowan and oak was highest in conifer-dominated forest; beech was about equally successful in conifer-dominated and broadleaved forests, and ash was very successful in broadleaved forest. Oak regeneration may be problematical in broadleaved forests, but we suggest this is not the case in conifer-dominated forests (where oaks have rarely been studied). Sapling densities of the species in the forest types were not consistently correlated with productivity, but birch and aspen generally regenerated strongest at intermediate and at high productivity, respectively. In noble forests, oak, ash and elm regenerated strongest at low productivity. The role of asexual regeneration (sprouting) remains to clarify. Our results suggest that lime, elm, ash and some other trees currently are limited mainly by poor dispersal, rather than habitat availability. The results are promising for various forms of mixed-species forestry that does not require planting (or little planting) and that would be beneficial for nature conservation. [Copyright &y& Elsevier] more...

• The death of a single tree or group of trees create small-scale canopy gaps. • Small-scale canopy gaps increase species richness, diversity and abundance of birds. • Large snags accumulated in canopy gaps enhance species richness and abundance. • Cavity- and ground-nesting birds benefit from gap presence. • Priority conservation species benefits from gap presence in deciduous forests. Canopy gaps produced by natural disturbances are an important source of structural and functional heterogeneity within forest ecosystems. However, the effect of natural, small-scale canopy gaps, caused by the mortality of a single tree or a group of trees, on bird assemblages has not been adequately addressed in temperate deciduous forests. We studied the effects of small-scale canopy gaps on the breeding birds of old-growth deciduous forests in the Carpathians (SE Poland). Our hypothesis was that such small gaps and the adjacent closed-canopy forest would differ in bird richness, diversity and relative abundance. Breeding bird assemblages were surveyed using point counts in 30 canopy gaps (mean area 301 m2 ± 228 SD, range: 37–970 m2) and in 30 control plots situated in the adjacent closed-canopy forest. The species richness, diversity and relative abundance of birds were significantly higher in the gaps than in the control plots and were correlated with the number of large snags. Collared Flycatcher Ficedula albicollis and White-backed Woodpecker Dendrocopos leucotos occurred more frequently in the gaps than in the control plots. Eurasian Treecreeper Certhia familiaris , Blackcap Sylvia atricapilla , Song Thrush Turdus philomelos and Eurasian Nuthatch Sitta europaea were more abundant in the gaps than in the control plots. The species richness of cavity- and ground-nesters was higher and these birds were more abundant in the gaps than in the control plots. The presence/absence of a gap and the number of large snags recorded in it explained 35.4% and 52.7% of the deviance in the total number of species and the total number of individual birds, respectively. Our results indicate that even small-scale canopy gaps, in combination with the large snags recorded in them resulting from the death of a single tree or group of trees, affect bird assemblages in deciduous forests as measured by the occurrence or abundance of individual species or community indices. We suggest that treefall gaps, which are heterogeneous structures, mediate the spatial distribution of bird territories within a stand and are crucial for the biodiversity of temperate deciduous forests. [ABSTRACT FROM AUTHOR] more...

• We evaluated canopy, bark, and leaf traits of upland oaks and common competitors. • Canopy, bark, and leaf litter traits of upland oaks were often those that promote fire. • American beech, red maple, and sugar maple traits were linked to low flammability. • Fire suppressing traits of many oak competitors could limit fire restoration. Shade-tolerant, fire-intolerant tree species are expanding in historically oak-dominated landscapes in the central and eastern U.S. Once established, these species are hypothesized to accelerate their own expansion through canopy, bark, and leaf litter traits that decrease forest flammability, consequently hindering the growth and survival of pyrophytic, shade-intolerant upland oaks (Quercus spp.). To better understand how canopy, bark, and leaf litter traits associated with flammability differ between oaks and common competitors, we quantified these traits in an upland oak forest in western Kentucky for four oak species and five non-oak species varying in shade and fire tolerance. Compared to oaks, American beech (Fagus grandifolia Ehrh.), red maple (Acer rubrum L.), and sugar maple (A. saccharum Marshall.) had: (1) wider, deeper canopies, traits associated with shadier, cooler understory conditions and higher fuel moisture; (2) thinner, smoother bark, traits that increase fire susceptibility, yet produce higher stemflow volume and potentially moister fuels near the tree's bole; and (3) leaf litter with a higher specific leaf area and surface area:volume ratio, traits linked to higher fuel bed bulk density and fuel moisture. Hickory (Carya spp.) and tulip poplar (Liriodendron tulipifera L.) traits were generally similar to that of oaks. Our findings show that non-oak tree competitors commonly found in upland oak forests display canopy, bark, and leaf litter traits often associated with low flammability, but that the number and array of non-flammable traits varies widely by species and sometimes changes with tree size, leading to a gradient of traits and potentially fire dampening abilities. If these species continue to expand, reduced flammability could limit prescribed fire effectiveness in upland oak restoration. [ABSTRACT FROM AUTHOR] more...

• Bird assemblages of oak-dominated forests of the Western Carpathians were compared. • Overall bird diversity was found to be similar in managed and protected stands. • Shelterwood systems sustained the overall biodiversity of birds. • Species in annex 1 of the Birds Directive are mostly restricted to nature reserves. • Unmanaged oak-dominated forests are important for Carpathian bird diversity. Forest management practices have varying impacts on biodiversity because the treatments and their outcomes do not always reflect the natural processes that maintain biodiversity. These management activities can be assessed using indicator species, among which birds are most frequently used. In 2018 we compared bird assemblages in oak (Quercus spp.)-dominated forests with admixtures of European beech (Fagus sylvatica), hereafter referred to as oak-beech forests, between managed and natural forest stands on opposite sides of the Carpathian range (south-facing in Slovakia and north-facing in Poland). The aim was to quantify and model the relationships between the quantitative parameters of bird assemblages and the main habitat parameters, as influenced by differing intensities of forest management. The point-count method with limited distance was applied to census birds (N = 100). Overall forest bird assemblages were found to be similar in respect to diversity indexes in managed and protected areas, as well as between southern and northern slopes of the Western Carpathian range, but all these types of forest differed in respect to bird species composition. However, both geographic location and management intensity, altogether with forest complexity contributed the mostly in explanation of bird diversity. The greatest differences were recorded for rare species, particularly those annexed in the Birds Directive of the European Union (mainly woodpeckers and flycatchers), as these birds were found either exclusively or in much greater numbers in nature reserves. Management intensity, forest complexity, and topography best explained the diversity of rare birds. Silvicultural systems applied in management of the Carpathian oak-beech forests, particularly the shelterwood system, seem to be sufficient for the preservation of overall bird diversity. However, decreased forest fragmentation and increased deadwood amounts are necessary measures to provide more close-to-nature stand structures, which will help support higher diversity of most bird species associated with mature forests. Because the oak-beech forests comprises only about 15% of the total forest area in the Western Carpathians, creating a network of natural or close-to-nature forest patches is recommended for the conservation of forest birds (and whole forest communities), including species annexed in the Birds Directive. Conservation priorities should be focused mainly in areas of harsh topography, where reduced wood production in these forests would have a less detrimental effect on the local forestry communities. These actions should also greatly improve the nature conservation system in the Carpathians and more generally throughout Central Europe. [ABSTRACT FROM AUTHOR] more...