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Continuous cover forestry maintains many characteristics of uneven-aged natural forests and aims to preserve biodiversity. Gap-cutting is a management option that may create a balance between timber production and continuous forest cover. We investigated the effect of newly created gaps on ground-dwelling spider assemblages in a managed oak forest, in the Pilis Mts., Hungary. Between 2018–2021 we sampled newly created elongated and circular-shaped gaps of two different sizes in a six-times replicated randomised complete block design. Pitfall samples of ~4600 spiders indicated that spider species richness was moderately higher in the gaps than in control stands. Spider assemblages did not respond in a specific way to the different gap implementations, but their variation in species composition was considerably higher in gaps than in the control plots. The excess spider abundance and species number in gaps, as compared to control, increased over the observation period, as did the dissimilarity of gap assemblages to control. Species responses imply that gaps create a variation in microhabitats and microclimatic conditions, resulting in spiders' diversification. The overall effect of gaps on spider assemblages suggests that gap-cutting is a suitable management option that preserves forest spider assemblages. [ABSTRACT FROM AUTHOR]

Because of their steep gradients in abiotic and biotic factors, mountains offer an ideal setting to illuminate the mechanisms that underlie patterns of species distributions and community assembly. We compared the composition of taxonomically and functionally diverse fungal communities in soils along five elevational gradients in mountains of the Neo‐ and Palaeotropics (northern Argentina, southern Brazil, Panama, Malaysian Borneo and Papua New Guinea). Both the richness and composition of soil fungal communities reflect environmental factors, particularly temperature and soil pH, with some shared patterns among neotropical and palaeotropical regions. Community dynamics are characterized by replacement of species along elevation gradients, implying a relatively narrow elevation range for most fungi, which appears to be driven by contrasting environmental preferences among both functional and taxonomic groups. For functional groups dependent on symbioses with plants (especially ectomycorrhizal fungi), the distribution of host plants drives richness and community composition, resulting in important differences in elevational patterns between neotropical and palaeotropical montane communities. The pronounced compositional and functional turnover along elevation gradients implies that tropical montane forest fungi will be sensitive to climate change, resulting in shifts in composition and functionality over time. [ABSTRACT FROM AUTHOR]

Aim: Dead wood‐inhabiting bryophyte communities are formed by several important factors. Besides the amount, quality and continuity of the substrate, there are also external factors indirectly influencing their structure. One of the most important is local microclimate. This fact has been recognized by many previous authors, yet studies exploring the direct effect of the microclimate on epixylic bryophytes are still sparse. Based on directly measured values of local temperature, air humidity and canopy openness (CO), we explored the associations between microclimate and epixylic bryophyte communities. Location: Old‐growth mixed Fagus sylvatica‐Abies alba montane forest in the Czech Republic (West Carpathians). Methods: The associations between microclimate and bryophyte communities were studied on 61 large logs of Abies alba in advanced decay stage. Air temperature and humidity were measured in three periods of the year 2017, CO was measured in leafless and leaf‐on periods. Water potential (Ψ) values were calculated from the data. The importance of the seasons was compared, the effect of microclimate variables on the species composition of logs was explored by canonical correspondence analysis. The effect on total cover and species richness was analyzed by linear models. Results: Our analysis revealed a clear relationship between the communities and the microclimatic gradient. The most important factors for bryophyte composition were the spring and summer water potential and CO in the leaf‐on period. Total species richness and cover increased with increasing water potential (relatively cool and humid conditions). Also, the appearance of sensitive epixylic specialists (mainly liverworts) was positively correlated with these microclimatic conditions. On the other hand, species more tolerant to desiccation preferred logs with a drier and warmer microclimate. Conclusions: Comparing logs with similar physical properties but different microclimates, we confirmed that epixylic bryophyte communities are significantly associated to microclimatic conditions in natural temperate forest. [ABSTRACT FROM AUTHOR]

A stable below‐canopy microclimate of forests is essential for their biodiversity and ecosystem functionality. Forest management necessarily modifies the buffering capacity of woodlands. However, the specific effects of different forestry treatments on site conditions, the temporal recovery after the harvests, and the reason for the contrasts between treatments are still poorly understood. The effects of four different forestry treatments (clear‐cutting, retention tree group, preparation cutting, and gap‐cutting) on microclimatic variables were studied within a field experiment in a managed oak‐dominated stand in Hungary, before (2014) and after (2015–2017) the interventions by complete block design with six replicates. From the first post‐treatment year, clear‐cuts differed the most from the uncut control due to the increased irradiance and heat load. Means and variability of air and soil temperature increased, air became dryer along with higher soil moisture levels. Retention tree groups could effectively ameliorate the extreme temperatures but not the mean values. Preparation cutting induced slight changes from the original buffered and humid forest microclimate. Despite the substantially more incoming light, gap‐cutting could retain the cool and humid air conditions and showed the highest increase in soil moisture after the interventions. For most microclimate variables, we could not observe any obvious trend within 3 yr. However, soil temperature variability decreased with time in clear‐cuts, while soil moisture difference continuously increased in gap‐ and clear‐cuts. Based on multivariate analyses, the treatments separated significantly based mainly on the temperature maxima and variability. We found that (1) the effect sizes among treatment levels were consistent throughout the years, (2) the climatic recovery time for variables appears to be far more than 3 yr, and (3) the applied silvicultural methods diverged mainly among the temperature maxima. Based on our study, the spatially heterogeneous and fine‐scaled treatments of continuous cover forestry (gap‐cutting, selection systems) are recommended. By applying these practices, the essential structural elements creating buffered microclimate could be more successfully maintained. Thus, forestry interventions could induce less pronounced alterations in environmental conditions for forest‐dwelling organism groups. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Regeneration assemblage is driven by the characteristics of the current forest stand. • High tree species diversity enables heterogeneous regeneration. • Various tree size distribution, large trees, and light also play key roles. • Individual species are also influenced by forest site, landscape, and land use history. • Management should maintain structurally and compositionally heterogeneous stands. Abstract As modern silviculture in natural forests is based on natural regeneration, finding the most important drivers of regeneration is crucial for forestry as well as conservation. We explored the relationship between numerous environmental and land use history variables and the species richness, cover and composition of the regeneration layer, and also the cover of the dominant species of the regeneration (sessile oak, hornbeam and beech) in coniferous-deciduous mixed forests. We identified the key factors which forest management can influence to support the regeneration of mixedwoods. Thirty-four stands were sampled, representing different tree species combinations and stand structures. We used redundancy analysis to explore the effects of the explanatory variables on the regeneration's species composition, and general linear modelling to examine their effects on its species richness and cover. The most important drivers of species composition were tree species richness, the amount of relative diffuse light, the proportion of beech in the overstory, and the heterogeneity of the diameter of trees. The cover of the regeneration layer was positively related to the density of large trees and to the amount of relative diffuse light. Its species richness was most strongly influenced by light and tree species richness. For the cover of a particular species in the regeneration, the proportion of the conspecific species in the overstory was determinant for every species, but other, various drivers also played a role in the case of the different species. According to our results, the community variables of the regeneration are mainly driven by the characteristics of the current forest stands, thus they are strongly influenced by management. Compositional heterogeneity of the overstory, various tree size distribution and the presence of large trees play key roles in the maintenance of a heterogeneous regeneration layer. The shelterwood forestry system is partially capable of providing these conditions, but continuous cover forestry is much more suitable to achieve them. Besides the stand structural variables, among the drivers of the individual species, various variables of forest site, landscape and land use history also occurred. Therefore, we conclude that maintaining the landscape-scale heterogeneity of forest types and management systems may promote the coexistence of various species in the region. [ABSTRACT FROM AUTHOR]

Policies to mitigate climate change and biodiversity loss often assume that protecting carbon‐rich forests provides co‐benefits in terms of biodiversity, due to the spatial congruence of carbon stocks and biodiversity at biogeographic scales. However, it remains unclear whether this holds at the scales relevant for management, and particularly large knowledge gaps exist for temperate forests and for taxa other than trees. We built a comprehensive dataset of Central European temperate forest structure and multi‐taxonomic diversity (beetles, birds, bryophytes, fungi, lichens, and plants) across 352 plots. We used Boosted Regression Trees (BRTs) to assess the relationship between above‐ground live carbon stocks and (a) taxon‐specific richness, (b) a unified multidiversity index. We used Threshold Indicator Taxa ANalysis to explore individual species' responses to changing above‐ground carbon stocks and to detect change‐points in species composition along the carbon‐stock gradient. Our results reveal an overall weak and highly variable relationship between richness and carbon stock at the stand scale, both for individual taxonomic groups and for multidiversity. Similarly, the proportion of win‐win and trade‐off species (i.e., species favored or disadvantaged by increasing carbon stock, respectively) varied substantially across taxa. Win‐win species gradually replaced trade‐off species with increasing carbon, without clear thresholds along the above‐ground carbon gradient, suggesting that community‐level surrogates (e.g., richness) might fail to detect critical changes in biodiversity. Collectively, our analyses highlight that leveraging co‐benefits between carbon and biodiversity in temperate forest may require stand‐scale management that prioritizes either biodiversity or carbon in order to maximize co‐benefits at broader scales. Importantly, this contrasts with tropical forests, where climate and biodiversity objectives can be integrated at the stand scale, thus highlighting the need for context‐specificity when managing for multiple objectives. Accounting for critical change‐points of target taxa can help to deal with this specificity, by defining a safe operating space to manipulate carbon while avoiding biodiversity losses. Can managing forests for storing carbon jointly achieve biodiversity conservation and climate change mitigation goals? Global and regional environmental policies often assume co‐benefits between carbon and biodiversity, but it is unclear whether this assumption holds at fine scales relevant for management. By modelling the carbon–biodiversity relationship for a broad range of taxa in temperate forests, we found that biodiversity and carbon stocks are not well‐aligned spatially at stand‐scale, and their relationship varied substantially across taxa. This suggests that forest management aimed at storing carbon may benefit some taxa but harm others, highlighting that broad‐scale co‐benefits may break down at fine scales. [ABSTRACT FROM AUTHOR]

• Understorey variables were analysed following experimental silvicultural treatments. • Five treatment types represented rotation and selection silvicultural systems. • Understorey responses were highly variable over time and across treatments. • Gap cuttings were less susceptible to ruderal and invasive species than clear-cuts. • Retention tree groups can be key in supporting forest understorey species. Forest management has a major impact on the understorey vegetation, with the intensity and type of the applied silvicultural treatments driving variable vegetation responses. We compared understorey variables across different experimental silvicultural treatments in a temperate oak-hornbeam forest in Central Hungary. Five treatment types were used in six replicates representing rotation and selection silvicultural systems: control (C), clear-cutting (CC), gap-cutting (G), preparation cutting (P), and retention tree group (R). The response of several understorey variables was investigated to the treatments in the first six years after their implementation in 2014. We assessed how understorey variables change in response to different forestry treatments, how these responses vary with time, and how game exclusion affects them. We then evaluated how well the treatments can preserve the forest character of the vegetation. We found a large temporal variability in the understorey variables over the study period. In all cases, the interventions led to an initial increase in species richness, followed by a decline later, where the regeneration layer started to close. The regeneration layer grew most intensively in G and CC. At the end of the study, R had the highest average species number, comprising a heterogeneous group of perennial forb species. The interventions all resulted in a rapid increase in total herb layer cover, mainly in favour of graminoid and perennial species. The extent of cover increase depended primarily on the amount of additional light received (CC > G > P > R > C). Turnover and beta diversity values also decreased in a similar order. The effect of game exclusion was especially pronounced in the case of the CC and G, where game browsing significantly slowed the regeneration outside the fences. The most significant changes in almost all variables were in the CC. It had the highest number of indicator species, many of them annual, disturbance-related, and invasive. G preserved the forest character of the vegetation better and proved to be less susceptible to the mass appearance of disturbance-related and invasive herbaceous species. Increasing the share of continuous cover forestry methods is crucial to preserve the forest herb layer. Rotation forestry with large cutting areas is not recommended or should be kept at low landscape rates, as these areas are highly exposed to disturbance-related and invasive species. Leaving retention tree groups can be key to the survival of numerous forest plant species. [ABSTRACT FROM AUTHOR]