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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., (© 2019 by the Ecological Society of America.)

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]

• 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]

Highlights: [•] Environmental constrains was assessed on epiphytic bryophytes and lichens. [•] Different tree species maintain different epiphyte assemblages. [•] Oak is a key species for bryophytes, while hornbeam for lichens. [•] Bryophytes are sensitive to microclimate continuity, lichens to light conditions. [•] Landscape and historical variables are less influential than local conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Environmental constrains was assessed on epiphytic bryophytes and lichens. [•] Different tree species maintain different epiphyte assemblages. [•] Oak is a key species for bryophytes, while hornbeam for lichens. [•] Bryophytes are sensitive to microclimate continuity, lichens to light conditions. [•] Landscape and historical variables are less influential than local conditions. [ABSTRACT FROM AUTHOR]

Forest management alters forest site; however, information is still limited about how different silvicultural treatments modify abiotic conditions. We compared the effects of four treatments from three different forestry systems on forest microclimate, litter, and soil conditions. The clear-cutting, retention tree group, preparation cutting, and gap-cutting treatments were experimentally established in a European oak-dominated forest, following a complete block design with six replicates. In this study, we show the results of the quantitative analyses of 21 variables, one year after the interventions. Strong treatment effects were observed for the microclimate and litter variables, whereas the soil characteristics remained similar. The increase in light was the highest in the clear-cuts with intermediate effects in the gap-cuts. The means and variances of the air and soil temperature as well as the vapor pressure deficit were the highest for the clear-cutting treatment. An increase in soil moisture, litter pH, and litter moisture was significant in the gap-cuts and, to a smaller extent, in the clear-cuts. The soil pH increased in the retention tree groups. Microclimatic differences between the treatments were the largest during the summer, which demonstrates the buffering effect of the canopy. Our study confirms that less intensive and more spatially heterogeneous silvicultural treatments (e.g., gap-cutting) preserve a stable below-canopy microclimate more effectively. These results can support and might be useful for both forest management and conservation planning. [ABSTRACT FROM AUTHOR]