The effect of light on different understory plant groups (herbs, ground floor bryophytes, trunkdwelling bryophytes and seedlings) was studied in a deciduous-coniferous mixed woodland in Western Hungary. The correlation of cover and species richness in each group and the cover of individual species to relative diffuse light were analyzed at different spatial scales. The study was carried out in 34 forest stands with different tree species composition. The importance of light in determining species composition was investigated by redundancy analysis. Species within each plant group were classified based on their light response. Light was positively correlated with species richness of herbs, cover of ground floor and trunkdwelling bryophytes, and species richness and cover of seedlings. In redundancy analysis, the variance explained by light was 13.0% for herbs, 15.0% for bryophytes and 8.6% for seedlings. Within the group of herbs, species preferring open conditions and light-flexible (gap) species were separated on the basis of the spatial scale of the analysis, while shade-tolerant species were not correlated positively with light. Among bryophytes mainly terricolous, opportunistic and mineral soil-inhabiting species showed significant positive correlations with light, while epiphytic and epixylic species did not respond to light. Seedlings of Quercus petraea and Pinus sylvestris were positively related to light, while most other seedling species were shade-tolerant. In case of vascular plants, the species' correlations with light were in agreement with their light indicator values; however, they were independent in the case of bryophytes. This study proved that the extent and spatial pattern of light influenced strongly the understory plant groups. Species within each group respond to light conditions differently, concerning the strength, direction and spatial scale of the relationships.

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This manuscript is contextually identical with the following published paper: Kovács, B.,

The effect of management related factors on species richness of epiphytic bryophytes and 24 lichens was studied in managed deciduous-coniferous mixed forests in Western-Hungary. At 25 2 the stand level, the potential explanatory variables were tree species composition, stand 26 structure, microclimate and light conditions, landscape and historical variables; while at tree 27 level host tree species, tree size and light were studied. 28Species richness of the two epiphyte groups was positively correlated. Both for lichen and 29 bryophyte plot level richness, the composition and diversity of tree species and the abundance 30 of shrub layer were the most influential positive factors. Besides, for bryophytes the presence 31 of large trees, while for lichens amount and heterogeneity of light were important. Tree level 32 richness was mainly determined by host tree species for both groups. For bryophytes oaks, 33 while for lichens oaks and hornbeam turned out the most favourable hosts. Tree size generally 34 increased tree level species richness, except on pine for bryophytes and on hornbeam for 35 lichens. 36The key variables for epiphytic diversity of the region were directly influenced by recent 37 forest management; historical and landscape variables were not influential. Forest 38 management oriented to the conservation of epiphytes should focus on: (i) the maintenance of 39 tree species diversity in mixed stands; (ii) increment the proportion of deciduous trees (mainly 40 oaks); (iii) conserving large trees within the stands; (iv) providing the presence of shrub and 41 regeneration layer; (v) creating heterogeneous light conditions. For these purposes tree 42 selection and selective cutting management seem more appropriate than shelterwood system. 43 44 45

The effect of tree species composition, stand structure characteristics and substrate availability on ground-floor bryophyte assemblages was studied in mixed deciduous forests of Western Hungary. Species composition, species richness and cover of bryophytes occurring on the soil and logs were analysed as dependent variables. The whole assemblage and functional groups defined on the basis of substrate preference were investigated separately. Substrate availability (open soil, logs) was the most prominent factor in determining species composition, cover and diversity positively, while the litter of deciduous trees had a negative effect on the occurrence of forest floor bryophytes. Besides, bryophyte species richness increased with tree species and stand structural diversity, and for specialist epiphytic and epixylic species log volume was essential. Sapling density and light heterogeneity were influential on bryophyte cover, especially for the dominant terricolous species. Many variables of the forest floor bryophyte community can be estimated efficiently by examining stand structure in the studied region. Selective cutting increasing tree species diversity, stand structural heterogeneity and dead wood volume can maintain higher bryophyte diversity in this region than the shelter-wood system producing evenaged, monodominant, structurally homogenous stands.

There are only few studies that explore the ecological consequences of forest management on several organism groups. We studied the short-term effects of four forestry treatments including preparation cutting, clear-cutting, retention tree group and gap-cutting in a temperate managed forest on the assemblage structure of understory plants, enchytraeid worms, spiders and ground beetles. Here we show, that the effect of treatments on the different facets of assemblage structure was taxon-specific. Clear-cutting and retention tree group strongly impoverished enchytraeids assemblages. Even if the species richness and cover of plants increased in clear-cutting and gap-cutting, their species composition moderately changed after treatments. For spiders only their species composition was influenced by the treatments, while the response of ground beetles was slightly affected. Short-term effect of forest management interventions on biodiversity might be compensated by the dispersal (spiders, ground beetles) and resilience (plants) of organism groups, however sedentary soil organism showed high sensitivity.

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response to experimental silvicultural treatments in a temperate oak-dominated forest.