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The lack of multi-dimensional data is one of the major gaps which limit the knowledge and the assessment possibilities of European forests. Nowadays, the most extensive and complete data on the European forest statuses are given by National Forest Inventories (NFIs) which provide information about the extent of forest's resources and their composition and structure. Traditionally, NFIs collect data related to trees, with a limited consideration of other habitat components, such as ground vegetation. This information which goes beyond the mere arboreal component is instead essential for a more complete forest biodiversity assessment. This paper is aimed at introducing the ICP Forests LI-BioDiv database which resulted from BioSoil Forest Biodiversity, a large collaborative European project. This database is organized as a multi-dimensional forest geodatabase that contains forest structure and vegetation records collected in 19 European countries in the period of 2005–2008. The data were acquired from 3311 geocoded plots where several different types of data were gathered: stand-level general information, tree-level data, deadwood, canopy closure and floristic composition. This paper is structured in order to: (1) give a clear overview of the raw data available in the database and to (2) present an elaboration of raw data to calculate simple plot-level forest variables (biomass, deadwood volume, alpha diversity). On the basis of the results we achieved, the LI-BioDiv database appears useful mainly for research purposes aimed at studying cross-relationships between multiple forest variables and not for an operative use for monitoring and assessing European forest. In particular, we hope that this contribution can stimulate scientists to carry out cross-analysis of the database for defining future forest biodiversity indicators that could be introduced into the field protocols of the NFIs in Europe. [ABSTRACT FROM AUTHOR]

Forests in Central Europe have been used since centuries and were systematically changed by silvicultural practices since the late 1700s. Focusing on possible biodiversity losses, forest stand management primarily impacts on the biodiversity attributes 'composition, structure and functioning' that are interlinked and incorporate different organizational and spatial ecosystem levels. Forest stand management can manipulate tree species diversity, which in turn affects stand structure and finally leads to changes in forest functions and services. We used meta-analyses to review 49 papers with 197 comparisons on compositional and structural diversity between unmanaged and managed forests as well as 53 comparisons of biomass productivity between mixed and monoculture forests throughout the temperate biome of Europe. Besides management impacts, for species and structural comparisons, we took time since abandonment of forest stand management into consideration when dealing with unmanaged forests. For species richness and diversity, we could not detect significant management effects; no significant influences of time since abandonment of management could be identified either. Structural attributes partly revealed considerable responses to forest stand management. Importantly, deadwood quantity, the number of microhabitats, and tree size diversity were reduced by forest stand management, while no effect was found for stand basal area and the number of living trees. Some of these effects become more pronounced with increasing time since abandonment. Forest productivity was significantly enhanced by regular moderate thinning compared with untreated stands and by tree species mixing compared with monospecific stands. Based on these results, we discuss the role of direct and indirect silvicultural effects, interactions between biodiversity components, the problem of defining the unmanaged reference state, and perspectives for forest stand management in practice. [ABSTRACT FROM AUTHOR]

Arboreal mammals are a group of special concern. We reviewed the available literature to summarize the overall potential effects of forest habitat disturbances on dormice ecology and population parameters. We took into consideration the influence of forest structure, area size and fragmentation, vegetation biodiversity, forestry treatments, and the development of road networks. The vast majority of studies have only examined two species, hazel and edible dormouse, while the ecological requirements and conservation priorities of forest, garden, and Japanese dormice have rarely been studied. There has been a substantial increase in the number of dormice studies; however, many aspects of their ecology are still unknown. The current state of knowledge points to the essential role of the complex vertical structure of forest vegetation in providing arboreal movement corridors and safe nesting places for dormice species. Moreover, dormice species are cavity dwellers that depend on the presence of old trees and nest boxes, which could have ambiguous effects. [ABSTRACT FROM AUTHOR]

Assessing forest biodiversity, naturalness and old-growth status (B-N-OG) is crucial for supporting sustainable forest planning, yet comprehensive monitoring networks specifically designed for such purposes are lacking in many countries. National Forest Inventories (NFIs) are the official source of statistics on status and trends of forests. While initially designed for wood production assessment, NFI data may be pivotal for ecological forest monitoring, thanks to their robust sampling protocols—enabling statistical inference—and regular field campaigns that ensure continuous information updates. As a consequence, in this study we explore the potential of NFIs for estimating B-N-OG indexes, aiming to establish compatible, scientifically relevant, and cost-effective indicators using existing NFI data at a European level. Based on data from the 2005 Italian NFI collected from 6563 plots, 18 indicators were selected following previous experiences and then used to estimate B-N-OG aggregated indexes. Relationships between the 18 indicators and the three indexes were investigated, along with comparisons of their relationships relative to forest type categories, management types and protected versus non-protected areas. Results confirm that NFI data offer valuable insights into specific B-N-OG indexes, especially concerning forest structure and deadwood. Moreover, the indexes contribute to developing meaningful relationships across geographic regions, forest categories and types of management. However, limitations in NFI field protocols are evident, as they are not explicitly designed for certain indicators. The study suggests the potential for NFIs to evolve into accessible, harmonized European reference networks for B-N-OG assessment for better supporting sustainable forest management, planning and conservation decisions related to forest ecosystems. [ABSTRACT FROM AUTHOR]

Global environmental changes drive biodiversity loss and community compositional change. Yet whether and how both factors simultaneously impact biomass dynamics in natural ecosystems remains elusive, especially considering their multidimensional effects (e.g., taxonomic, functional, and phylogenetic) over spatial scales. To fill this knowledge gap, we generated an experimental spatial gradient using circular quadrats that vary in radius (2–30 m) in a subtropical forest on Dinghushan Mountain, China. Within each quadrat over 10 years, we calculated the changes in aboveground biomass (i.e., net Δbiomass), biodiversity (i.e., Δbiodiversity for richness, Shannon diversity, functional, phylogenetic), and community composition (i.e., β-diversity for taxonomic, functional, phylogenetic). Based on multi-model inference, we determined the most parsimonious relationships of Δbiomass as a function of Δbiodiversity and β-diversity and then quantified their standardized coefficients in response to the spatial gradient. Our results showed that Δbiomass, Δbiodiversity, and β-diversity decreased with quadrat size; the former at an accelerating rate and the latter at decelerating rates. While Δbiomass as a function of Δbiodiversity and β-diversity had low occurrences across the gradient, Δbiomass was strongly related to the change in functional dispersion (i.e., ΔFDis) and taxonomic β-diversity at larger spatial scales. Our results suggest scale-dependent influences of biodiversity loss and community compositional change on biomass dynamics in natural ecosystems. Further, our results highlight that multiple dimensions of biodiversity should be considered when predicting biomass dynamics at large spatial scales. [ABSTRACT FROM AUTHOR]

In the modern forestry paradigm, many factors influence the amount of coarse woody debris (CWD). The present paper analyzes the effects of both local (national) programs (special functions of forests) and European programs (Natura 2000 sites), as well as the individual characteristics of forest stands. The study was conducted on 2,752 sampling plots distributed over an area of about 17,500 ha and located in lowland stands having a species composition typical of large areas in central Europe. Natura 2000 areas contained significantly more CWD (8.4 m/ha) than areas not covered by the program (4.8 m/ha). However, this is due to the fact that Natura 2000 sites involve well-preserved forest areas, such as nature reserves (26.6 m/ha). In the managed forests that have been covered by the Natura 2000 program over the past several years, the volume of CWD has not increased. Forests with ecological and social functions differed slightly in the amount of CWD. More CWD occurred in protected animal areas (8.7 m/ha) than in stands damaged by industry (3.9 m/ha). Intermediate CWD levels were found in water-protection forests and in forests located around cities and military facilities. In managed forests, the lowest CWD volume was observed in middle-aged stands. The species composition of the stand had little effect on the volume of CWD. Only stands with a predominance of ash and alder had higher CWD levels (13.5 m/ha). More CWD was found in stands whose species composition did not represent the potential site quality (6.4 m/ha) than in habitats with the optimum species composition (3.8 m/ha). CWD volume should be systematically increased taking into consideration local natural conditions. Such efforts should be focused on particularly valuable regions, and especially on Natura 2000 sites, where the threshold values reported from other European forests should be reached. Leaving some trees to die naturally and retaining reasonable amounts of such trees ought to be incorporated into CWD management practice in Poland. [ABSTRACT FROM AUTHOR]

In face of climate change and global scale biodiversity loss, assessing the relationship between biodiversity and forest ecosystem functioning is essential, but poorly investigated in temperate forests of Iran. We examined plant diversity aboveground biomass relationships in unmanaged, and forests managed with a single-stem selection system in the Hyrcanian forests ecoregion in Northern Iran. Also, the effect of single-stem selection system on soil nutrient and plant species diversity of tree layer was investigated. Linear models were used to analyze the effect of management and soil characteristics on aboveground biomass and tree layer attributes. Moreover, the relationships between aboveground biomass and plant species diversity metrics and soil characteristics were investigated using simple linear and multiple linear regression analysis by using regression analysis. We found that tree layer species richness and Shannon diversity were significantly higher in managed forests compared to unmanaged forests. While simple regression analysis revealed no effect of tree layer diversity and soil characteristics on aboveground biomass, multiple regression analysis showed that the main positive driver of aboveground biomass was soil nitrogen content (or its equivalent soil organic carbon). These findings indicate that from a biodiversity point of view, the single-stem selection system can be considered a sustainable forest management approach in Hyrcanian forests because it has positive effects on tree layer diversity. This is probably driven by increased habitat heterogeneity and light availability at forest floor through cuttings, while keeping cutting intensity at a level that is too low to significantly affect tree biomass. While the relationship between soil nitrogen and biomass was positive, we found no relationship between species diversity and biomass. Finally, assessment of relationship between biomass and plant species diversity and other underlying factors such as soil nutrients can be considered an important tool to conserve and manage ecosystem services. [ABSTRACT FROM AUTHOR]

Small-scale private forests cover large areas in Europe and often contain structures and habitats of high nature conservation value that are increasingly put under pressure due to a rising interest in fuelwood and wood products. We investigate the distribution of variables like living tree and deadwood volumes, management intensity, diversity and density of tree-related microhabitats recorded in 81 small-scale private forest parcels in the Lower Saxon Hills (northwest Germany). We provide an assessment of the influence of predictors like the individual forest owners' goals and activities, as stated by them in a quantitative survey, as well as landscape parameters like parcel size, slope, landscape fragmentation and forest continuity. Our results indicate that there are two types of structures of conservation value in small-scale private forests: slowly evolving structures (type A) like large-diameter living trees and tree-related microhabitats which mostly depend on landscape parameters that act on longer time scales, and fast evolving structures (type B) like deadwood that are influenced by both owner attitudes and landscape parameters. The resulting implications for integrative forest and conservation management are discussed. When considering the conservation of the slowly evolving type A structures, long-term commitments to conservation legislation, financial incentives and generation-spanning education of forest owners are necessary. Efforts to promote the faster evolving type B structures might prove particularly advantageous in small-scale private forests given the structural diversity of the stands, but also the often strong identification of owners with their land. [ABSTRACT FROM AUTHOR]

Forests simultaneously provide multiple ecosystem services (ESs), but the trade-off and synergy among them were uncertain. Biotic and abiotic variables regulate forest ecosystem service multifunctionality (EMF); however, quantifying the relative contribution of them to EMF in natural forests at large scale was still limited. We examined the trade-off in ecosystem services and the drivers of EMF of natural temperate forests in northeast China. Six facets of ESs were derived based on 2227 national forest inventory sample plots, that is, water conservation, soil conservation, stand productivity, tree species diversity, carbon storage and soil fertility maintenance. Structural equation model was applied to quantify the driving forces of EMF including mean annual temperature (MAT), mean annual precipitation (MAP), total nitrogen (TN), soil pH (pH), stand age (Age), additive stand density index (aSDI), stand structural diversity (SSD) and tree species richness (SR). Our results indicated that the RMSD (root mean square deviation) values of the 15 ES pairs ranged from 0.13 to 0.25, and the trade-offs between biodiversity and other five ESs were high, with RMSD values greater than 0.2. We provided clear evidence that stand density was the most important driver of EMF, which affected the EMF indirectly through tree size diversity and species richness. Understanding the contribution of these factors to EMF can help to design sustainable forest management practices in northeast China aiming to foster and preserve multifunctionality. [ABSTRACT FROM AUTHOR]

Forest dieback in the last decade has been reported all over the world and not only causes a significant loss of forest yield but also affects successional trajectories. Here, we investigate the plant communities associated with Pinus mugo subsp. mugo dieback patches in Maiella massif. Dieback patches were examined by using satellite images to describe the occurrences and distribution. According to dieback patch size, we identified three ontogenetic stages: small, medium and large. To assess the effect of P. mugo on coexisting species, patch was divided into four belts according to P. mugo healthy status: OUT, FRONT, DEAD and IN zone. Within the four belt zones for each of the three ontogenetic stages, a vegetation analysis was conducted. Overall, 35 dieback patches were recorded and all are characterized by a circular shape and a size ranging from a few meters to 76.1 m. The linear correlation between the width of the inner regeneration belt and the total diameter of the patch suggests that the dieback area expands centrifugally due to the death of standing P. mugo. The increased resources, in terms of light availability caused by dieback, contribute to higher plants diversity in DEAD belts with the highest cover of hemicryptophytes. Contrariwise, in the OUT belts, not affected by dieback, plant diversity was the lowest with the highest cover of phanerophytes and a good contingent of nemoral species. Dieback affects forest structure and leads to sudden vegetation shifts that play an important role in maintaining biodiversity by allowing alternation between forest and grassland ecosystems. [ABSTRACT FROM AUTHOR]

The very rapid development of the road infrastructure in recent years has adversely affected the natural environment. The main effects of this have been the loss or deteriorating quality of habitats, the mortality of animals due to collisions with road vehicles, the withdrawal of birds as a result of disturbance and excessive noise in the neighbourhood of roads. In this study, we attempted to define the influence of a busy road on a breeding community of woodland birds. Individuals were counted using the point method at 54 observation points located at three various distances (60, 310, 560 m) from the road. At each point, we determined the habitat parameters and the intensity of noise. In total, 995 individuals of 39 species were recorded on the study plot. This study showed that the area was homogeneous with respect to habitat. The number of birds per point increased with distance from the road. Species diversity was lower near the road. The density of nine common species increased with distance from the road. Great Tit Parus major and Song Thrush Turdus philomelos preferred the neighbourhood of the road, whereas the numbers of the other species were the highest in the middle row of points. The number and species diversity of birds were correlated with the pattern of sound propagation across our study area. Our results showed that the species particularly sensitive to road traffic were those nesting near the ground and with low-frequency calls. [ABSTRACT FROM AUTHOR]

In the field of assessing forest ecosystem service provision and biodiversity, there seems to be a gap between an existing large body of valuable expert knowledge and its application. We propose fuzzy logic evaluation systems as a contribution to closing that gap. With this method-focused pilot study, we explored the potential of fuzzy logic for assessing the provision of different ecosystem services in a simulation case study, covering a large forest landscape in Southern Germany. Based on expert knowledge and available literature, we designed a fuzzy logic evaluation system for biodiversity, and the ecosystem services balanced wood production, storm and bark beetle damage resistance, and recreation value. This evaluation system was applied to 100-year simulation outcomes for three contrasting forest management scenarios in the landscape of interest. While the results of the case study in general support the idea of a multifunctional forest management, fuzzy logic turned out pronouncedly useful as a method. This is due to its potential to make otherwise unused expert knowledge applicable and transparent in a formal evaluation process. Based on our results, we discuss the approach related to its potential for interdisciplinary integration of knowledge, for revealing tradeoffs and synergies, and participative planning processes. [ABSTRACT FROM AUTHOR]

Many studies have been conducted on the effects of changes in plant diversity and species composition on ecosystem functioning and plant productivity due to climate change. However, a few studies have been conducted on the effects of species shifts on litter decomposition. In this context, we tested (i) the influences of litter species diversity on decomposition, (ii) deviation of litter mixtures decomposition from expected patterns (non-additive effects), and (iii) tree species loss or gain impact on the decomposition process. We performed a complete factorial decomposition experiment in a gradient of tree litter species diversity in a semi-arid Mediterranean oak forest for 550 days. Among species, only C, lignin, and water holding capacity (WHC) values varied significantly in initial litter characteristics. The litter mass loss at the end of the experiment differed significantly between Q. brantii and P. glabra. Initial lignin content and C/N ratio had the main effects on the decomposition rate. Lignin content was the best predictor of the overall decomposition rate in this region. Contrary to other ecosystems where synergistic non-additive effects are dominant, we observed 82% of additive and 18% of non-additive effects on litter mass and chemical components loss. Turnover of plant species due to climate change could negatively affect the litter decomposition and nutrient release from litter mixture in the semi-arid Mediterranean region. [ABSTRACT FROM AUTHOR]

Selective harvesting is a common silvicultural practice to ensure sustainable use of uneven-aged forests, but our understanding of how multiple forest attributes interact to regulate aboveground biomass (AGB) dynamics following selective harvesting remains limited. Using repeated measurements of 13,996 stem-mapped trees distributed in a broad-leaved Korean pine forest (BKPF), we evaluated the recovery trajectory of AGB over a 7-year period following selective harvesting of different intensity: low (15.8% of basal area removed), medium (29.4%) and high (51.4%). In particular, we examined the effects of (1) tree species diversity, (2) stand structure and (3) the post-harvest density on the rate of AGB accumulation (the net annual increment). Despite the enhanced growth of residual trees by all harvesting treatments, rates of AGB accumulation declined with increasing harvesting intensity due to high mortality losses: mean mortality rates of high stands were more than double those of the unharvested stands. Small trees (DBH < 10 cm) suffered greatest mortality because of their sensitivity to changes in environmental conditions. Post-harvest stand biomass and basal area explained most of the variation in the rate of AGB accumulation, followed by stand structural attributes (quadratic mean diameter and growth dominance coefficient), while indices of species diversity (richness, Shannon diversity and evenness) were weak predictors. Our findings suggest that selective harvesting may promote forest production without loss of biodiversity and stimulate the growth of residual trees (particularly small-sized trees, as indicated by the reverse growth dominance) within BKPFs, but harvest intensities should not exceed ~ 30% basal area removed, because higher levels of harvesting are likely to cause serious delays in biomass recovery. [ABSTRACT FROM AUTHOR]

The spatial variation of forest soil nutrients influences the species composition, distribution and diversity of forest plants, because soil nutrients are the most important environmental factors limiting the growth and survival of plants. We analyzed the effect of the spatial heterogeneity of soil nutrients on understory vegetation diversity in broadleaved-Korean pine forest, which had been undergone cutting disturbance. The results are of great significance in the sustainable management of the broadleaved-Korean pine forest and understanding the mechanism of correlation between heterogeneity and diversity. We sampled four plots of broadleaved-Korean pine forest in Jiaohe Forestry Bureau in Jilin province, China. Plot A, a control, was unlogged broadleaved-Korean pine forest. In plot B, C and D, forest was cut at 20%, 35% and 55% of the intensity in 2011. Cutting intensity influenced significantly on total nitrogen (TN), total phosphorous (TP), pH, soil organic matter (SOM), nitrate nitrogen (NN) and ammoniacal nitrogen except total potassium (p < 0.05). The values of TN, TP, pH and SOM showed that their quantities could decrease as cutting intensity increased. Species richness and diversity index of woody plants could increase in proportion to the cutting intensity, but species richness and diversity index of herbaceous plants might tend to decrease in early spring and summer. Coefficient of variation of TN, TP, SOM and NN could have either a positive or negative correlation with α-diversity indices of woody and herbaceous plants, while the other soil nutrient indices could have no correlation with diversity indices. [ABSTRACT FROM AUTHOR]

Habitat trees, which provide roosting, foraging and nesting for multiple taxa, are retained in managed forests to support biodiversity conservation. To what extent their spatial distribution influences provisioning of habitats has rarely been addressed. In this study, we investigated whether abundance and richness of tree-related microhabitats (TreMs) differ between habitat trees in clumped and dispersed distributions and whether the abundance of fifteen groups of TreMs is related to tree distribution patterns. To identify habitat trees, we quantified TreMs in temperate mountain forests of Germany. We determined clumping (the Clark–Evans index), size of the convex hull, diameter at breast height, as well as altitude, slope and aspect of sites for their possible influence on TreMs. We additionally determined the difference in TreM abundance and richness among four options of selecting five habitat trees per ha from 15 candidates: (a) the most clumped trees, (b) five randomly selected and dispersed trees, (c) the single tree with highest abundance or richness of TreMs and its four closest neighbors and (d) a "reference selection" of five trees with known highest abundance or richness of TreMs irrespective of their distribution. The degree of clumping and the size of the convex hull influenced neither the abundance nor richness of TreMs. The reference selection, option (d), contained more than twice the number of TreMs compared to the most clumped, (a), or random distributions, (b), of five habitat trees, while option (c) assumed an intermediate position. If the goal of habitat tree retention is to maximize stand-level abundance and richness of TreMs, then it is clearly more important to select habitat trees irrespective of their spatial pattern. [ABSTRACT FROM AUTHOR]

Steadily increasing damage to Norway spruce forests in Europe has caused researchers and managers to consider whether these forests can be converted to more stable ecosystems. In a central European mountain region, we investigated whether management systems (MSs) specified by regional stakeholders provide sound alternatives to the currently applied management. We used the forest model Sibyla to explore whether the tested MSs differ in their sensitivity to climate change in terms of altered biomass production, stand structure, forest damage, and financial outcome. The tested MSs were no-management (NM), currently applied management (BAU), and management based on the preferences of forest managers (FM) or on the preferences of other stakeholders (OSH). With NM, spruce remained dominant during the simulation period 2010-2100, and the rate of damage significantly increased. Spruce also remained dominant with FM, while the abundance of non-spruce species significantly increased with BAU and OSH. The rate of salvage logging converged at 50% of the total harvest for all MSs up to 2050. Climate change reduced biomass production (−15%) with all MSs but had a negligible effect on biodiversity indicators. The average initial value of the simulated stands was 20,000 € ha and the nominal value in 2100 was between 1900 and 10,900 € ha. The Net Present Value calculated with the 2% interest rate was negative during the whole simulation period (−5600 to −18,500 € ha in 2100). Effect of climate change on all financial indicators was negative. Our findings indicate that secondary spruce forests are highly vulnerable and that the systems proposed by both forest managers and other regional stakeholders failed to significantly reduce forest damage and stabilize forest production. [ABSTRACT FROM AUTHOR]

The study focuses on identifying and assessing the effect of the presence of drainage and roadside ditches on the diversity of bryophytes in managed forests. We compared the composition of moss and liverwort species, their richness and abundance in plots that are located in ditches as well as corresponding control plots in the surrounding forests with regard to the forest type (coniferous, mixed and deciduous). ANOVA demonstrated the pronounced impact that the presence of ditches in managed forests has on an increase in bryophyte species richness. A comparison of forest and ditch types using DCA pointed to a correlation between the number of deciduous trees in the stands and an increased dissimilarity of ditch bryophytes when compared to the bryophytes of the corresponding control plots. Using the ecological indicator values, CCA confirmed the special significance of ditch settlements for hygrophilous species, which at present cannot otherwise find favorable conditions in managed forests. The study proves that ditches, and especially those with intermittent pools of stagnant water, may become a significant source of microhabitat diversity. Their presence may provide a welcome preserve for rare and protected species that cannot find suitable substrates in managed forests. [ABSTRACT FROM AUTHOR]

The Forest Stewardship Council (FSC) forest certification system is a globally widespread market-driven mechanism that aims at responsible use and governance of forests, and its application is growing. However, the extent to which forest certification contributes effectively to maintaining forest biodiversity is an unresolved issue. We assessed the role of FSC certification for forest biodiversity conservation in Lithuania's state forests. First, we analysed the indicators related to biodiversity conservation at different spatial scales in the FSC standard used in Lithuania. By applying morphological spatial pattern analysis and habitat suitability modelling, we explored the structural and functional connectivity of forest habitat patches of formally and voluntarily set-asides for biodiversity conservation. According to the Lithuanian FSC standard, active measures in forest management for biodiversity should be imposed at three spatial scales: 'trees in a stand', 'stands in a landscape', and 'landscape in an ecoregion'. The total area set aside for biodiversity was 18.6 %, including 4.9 % voluntary set-asides. The quality of habitats in terms of forest stand age was low, only 9.4 % of all set-asides constituted older forests. The proportions of voluntary set-aside area varied among the different state forest enterprises, and the results indicated a clear trend to set aside non-forest or low productivity forest habitats. Small (<1 ha) habitat patches formed a major part of all set-asides, including formally protected areas. FSC certification alone was not able to maintain structural and functional connectivity of forests for species at multiple spatial scales in Lithuania. By keeping a minimum standard of 5 % forestland set aside for biodiversity, the state forest enterprises certified according to the FSC can only satisfy forest species with small habitat requirements. To maintain biodiversity, place-based learning among stakeholders for representative functional green infrastructures in concrete landscapes and regions, combined with transparent knowledge about the net effect of pressures and responses on the state of biodiversity, are necessary. [ABSTRACT FROM AUTHOR]

Changing natural disturbance regimes threaten forest functions in the Northern Calcareous Alps, with steep, sun-exposed sites on shallow soils at particular risk due to inhibited recovery. Natural tree regeneration after severe disturbances may fail due to extreme microclimate, dense layers of competing understorey vegetation and herbivory. In order to gain insight into regeneration patterns and dynamics, chronosequences of disturbed forest sites were selected along a longitudinal section of the Austrian Northern Calcareous Alps. Regeneration densities of trees, cover of competing vegetation and microsite characteristics were recorded on a total of 19 disturbed sites and in the respective adjacent forest stands. Although high densities of germinants and small seedlings (≤0.1 m) were recorded in the forest stands, recruitment establishment (trees >0.1 m) frequently failed on both disturbed sites and adjacent stands. In fact, half of the disturbed sites were found to be without sufficient regeneration and no significant increase of regeneration density was detected with time since disturbance. Overall, regeneration densities reflect a very critical situation along the disturbance chronosequence. Even if seedling banks are composed of individuals smaller than 0.1 m, seedling mortality is high. General linear mixed models revealed positive effects of convex microsites and thick organic layers on Picea abies (L.) Karst. establishment, while dense litter and grass cover impaired spruce regeneration. Regeneration of other tree species was scarce. The results corroborate the urgent need for establishing seedling banks of larger individuals (>0.1 m) and for reducing ungulate browsing. They also underline the need for comprehensive long-term studies to better understand the dynamic processes, driving resilience of disturbed sites. [ABSTRACT FROM AUTHOR]

Process-orientated, unmanaged forest remnants are not sufficient for halting the loss of forest biodiversity. Thus, integrated biodiversity-promoting management for forest inhabitants is needed. Microhabitats, such as tree cavities or bark pockets, are essential for the preservation of saproxylic species and of critical importance for endangered ones. This study investigates (1) which factors trigger the formation of microhabitats at both the individual tree and aggregated plot level, and (2) whether the co-occurrence of microhabitats differs between managed (=logged) and unmanaged forests. Relationships between the occurrence of 17 microhabitat types and individual tree features (e.g. light availability, and tree vitality) and plot characteristics (e.g. stand density index and stand age) in 398 plots dominated by Fagus sylvatica or Pseudotsuga menziesii in Germany and the USA were studied using random-effects logistic and normal regression modelling. Separate analyses were performed for German beech forests, German Douglas-fir forests, and the US Douglas-fir forests. Our results show that (1) tree diameter in breast height (DBH), tree vitality and branchiness or epicormic branches are highly related with the occurrence of one or more microhabitats on individual trees in managed and unmanaged beech and US Douglas-fir forests. In managed German Douglas-fir forests, vitality is not a predictor for the occurrence of microhabitats on a tree, but tree density and the maximum age of trees in a stand in addition to DBH and branchiness have an effect. Time since last management is not a statistically significant predictor for the presence of microhabitats at the tree level, but it is for German beech at the plot level. In Douglas-fir-dominated forests both in Germany and in the USA, the stand density index was the only common predictor at the plot level. (2) Unmanaged German beech and Douglas-fir forests exhibit more statistically significant and positive correlations with microhabitat groups than managed stands, implying that the presence of one microhabitat group on a tree is associated with the presence of other microhabitat groups. We finally conclude that measures for supporting microhabitat inhabitants in managed forests are scale and species dependent (tree versus plot level; beech versus Douglas-fir-dominated forests). Trees that carry microhabitats seem to have similar features independently of forest management. At the plot level, density management may trigger the accumulation of microhabitats. Our results indicate that in forest management, it is possible to consider the factors influencing the formation of microhabitats and implement adequate forest practices to advance their formation. [ABSTRACT FROM AUTHOR]

Experimental forest plantations to study biodiversity-ecosystem functioning (BEF) relationships have recently been established in different regions of the world, but subtropical biomes have not been covered so far. Here, we report about the initial survivorship of 26 tree species in the first such experiment in subtropical China. In the context of the joint Sino-German-Swiss Research Unit 'BEF-China,' 271 experimental forest plots were established using 24 naturally occurring tree species and two native commercial conifers. Based on the survival inventories carried out in November 2009 and June 2010, the overall survival rate was 87 % after the first 14 months. Generalized mixed-effects models showed that survival rates of seedlings were significantly affected by species richness, the species' leaf habit (deciduous or evergreen), species identity, planting date, and altitude. In the first survey, seedling establishment success decreased with increasing richness levels, a tendency that disappeared in the second survey after replanting. Though evergreen species performed less well than deciduous species with establishment rates of 84 versus 93 % in the second survey, their planting success exceeded the general expectation for subtropical broad-leaved evergreen species. These results have important implications for establishing mixed-species plantations for diversity conservation and improvement of ecosystem functioning in the Chinese subtropics and elsewhere. Additional costs associated with mixed-species plantations as compared to conventional plantations also demonstrate the potential of upscaling BEF experiments to large-scale afforestation projects. [ABSTRACT FROM AUTHOR]

Norway spruce is one of the most important conifer tree species in Europe, paramount for timber provision, habitat, recreation, and protection of mountain roads and settlements from natural hazards. Although natural Norway spruce forests exhibit diverse structures, even-aged stands can arise after disturbance or as the result of common silvicultural practice, including off-site afforestation. Many even-aged Norway spruce forests face issues such as senescence, insufficient regeneration, mechanical stability, sensitivity to biotic disturbances, and restoration. We propose the use of Density Management Diagrams (DMD), stand-scale graphical models designed to project growth and yield of even-aged forests, as a heuristic tool for assessing the structure and development of even-aged Norway spruce stands. DMDs are predicated on basic tree allometry and the assumption that self-thinning occurs predictably in forest stands. We designed a DMD for Norway spruce in temperate Europe based on wide-ranging forest inventory data. Quantitative relationships between tree- and stand-level variables that describe resistance to selected natural disturbances were superimposed on the DMD. These susceptibility zones were used to demonstrate assessment and possible management actions related to, for example, windfirmness and effectiveness of the protective function against rockfall or avalanches. The Norway spruce DMD provides forest managers and silviculturists a simple, easy-to-use, tool for evaluating stand dynamics and scheduling needed density management actions. [ABSTRACT FROM AUTHOR]

Within Europe the question of plant coenosis is attracting growing interest. The quality and quantity of collected information on forest resources at a global level largely depends on the capacity to collect and analyse data at national and sub-national scale in a way compatible with those at global or continental levels. In Italy the acceptance of all the international agreements and protocols on the protection of the environment and management of natural resources, requires a standardization of collected information and statistics, with the aim to produce homogeneous and integrative data at global level. This need is reflected in the following points: (1) the adoption of a classification system of land use and forest cover compatible with international hierarchical systems and definitions; (2) the identification of standard procedures in data collection and data elaboration. To classify natural resources and, in this case study, forest resources, implies to order natural and semi natural coenosis, forest and pre-forest communities, in a systematic way, according to the applied variables and to the scale detail. The solution proposed in this case study is organised according to forest management, through the adoption of the habitat approach, describing forest and pre-forest types in a synoptic way and performing a system of nomenclature in agreement with the international standards initiatives. In this way, the characterization of forest types at community level is related to the environmental planning for the protection of biodiversity. [ABSTRACT FROM AUTHOR]