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The aim of this paper was inventory of the wild service tree (Sorbus torminalis), a very precious but, at the same time, one of the least known species of homeland wooded plants in the Taczanów Forest Inspectorate (Poznań Regional State Forest Directorate). The inventory was conducted from May 2010 to March 2011. The result of the inventory are 1127 specimens, of which 209 are strong mature trees and 918 are seedlings and young trees in good health. The field research shows that the wild service tree grows in the Taczanów Forest alongside its central and eastern part in 22 Forest Compartments, 8 of which are in the Koryta Forest District and 14 are in the Taczanów Forest District. The average height of mature trees (d1.3 > 10 cm) was 18.02 meters and the average breast height  dimension was 26.22 centimetres. The dominant forest type in this area which is acid oak forest from Quercetea roboli-petraeae class creates optimal conditions for the growth of the wild service tree. This is proved by an analysis of the species population dynamics which is characteristic for the species biology. The study shows that earlier inventories conducted in this region are incomplete and out-of-date, and this present inventory substantially broadens the knowledge about the wild service tree in the Taczanów Forest in the context of its local and national population.
The main properties of the soils under oak (Quercus robur L.) forests in Galicia (NW Spain) were characterized. Eleven edaphic parameters (pH, OM, N, C/N ratio, P, K, Ca, Mg, sand, silt and clay) were estimated in 39 soil samples. Siliceous substrates were present in all stands and the soils were found to be the cambisols. The values of chemical parameters are similar to those considered as the optimal ones by other authors (i.e., average pH close to 5, average C/N ratio close to 15) with the exception of the organic matter which is slightly higher; the average value is equal to 8.64 ± 5.19. The content of nutrients can be considered as the low or medium (for instance, the potassium is only 73 ppm) as compared with other forests in the study area, except the content of phosphorus, which is considerably higher (21.8 ppm versus 1–6 ppm).
Decomposition is an important carbon flux that must be accounted for in estimates of forest ecosystem carbon balance. Aim of this research is to provide estimate of fine woody debris decomposition rates for different tree species and sample sizes also taking into account the influence of specific microsite meteorological conditions on decomposition rates. In this paper we present results of the first two years of the experiment designed to last six years. Study was conducted in managed lowland oak forest in central Croatia. Decomposition rates (k) of fine woody debris (diameter 0.5–7 cm) for four species (Querus robur L., Carpinut betulus L., Alnus glutinosa Gaernt., Fraxinus angustifolia L.) in four size classes were estimated using litter bag method and mass loss equation of Olson (1963). Overall average k in our study was 0.182 ± 0.011 year-1. Results indicate that decomposition rate is affected by the size of the debris, with the smallest diameter branches (<1 cm) decomposing is significantly faster (k = 0.260 ± 0.018, P <0.05) than the larger one. Tree species from which debris had originated also affected decomposition, although to a lesser extent, with hornbeam samples having significantly (P <0.05) higher average decomposition rate (0.229 ± 0.028), compared to that of ash samples (0.141 ± 0.022). Proportion of variability in k explained by variables ‘species’ and ‘size class’ was assessed with general linear model (R² = 0.644) also taking into account variables like soil temperature and soil water content. Sample size class explained 22.2%; species explained only 9.4%, while soil water content and temperature combined explained 32.8% of the variance of k. Rate constants obtained within this study might be useful in modelling ecosystem carbon balance for similar lowland forest ecosystems in Europe.
In this study, we examine the pattern of occurrence of Impatiens parviflora in Central European oak forests over time and its ecological requirements within these types of communities. Research was based on phytosociological data collected in 3776 relevés. A modified TWINSPAN algorithm were used to distinguish the groups of oak forests. The ecological preferences of the I. parviflora and studied communities as well as differences between invaded and non-invaded vegetation plots were analyzed using mean weighted Ellenberg indicator values (EIVs). Finally, both the temporal pattern of I. parviflora participation and changes in its coverage in the studied communities were analyzed. Our study confirmed a high adaptability of this species with respect to temperature, moisture, soil reaction and nutrients and determined its broad ecological optimum in oak forests. However, it also revealed both a greater sensitivity of some communities within Central European oak forests to the invasion of I. parviflora and differences in habitat conditions between invaded and non-invaded vegetation plots. This suggests that the habitat niche of I. parviflora within oak forests is not accidental. The analysis of temporal changes in the frequency of I. parviflora confirmed a 20% increase in relevés over the last 50 years. However, we did not identify any statistically significant rise in the coverage of I. parviflora in oak forests specifically during the studied period.
Thermophilous oak wood is the most species-rich forest habitat in the zone of mixed deciduous forests. A very limited amount of it has been saved in good condition. We investigated the principal hypothesis that the vegetation and seed banks, especially of the ancient forest species, are good indicators of habitat naturalness and its aptitude for restoration. Vegetation and seed bank sampling were carried out in fragments of forest with a known management and disturbance history over the past 80 years. We predicted that natural and anthropogenic transformations of tree stands would be significant factors shaping species composition and similarity of vegetation and seed banks. The closest similarity was observed between the seed banks of plots which were never logged. The least related to others was the seed bank of the logged site, whose soil was ploughed prior to tree replantation. The highest number of ancient forest species was recorded in the vegetation (33 species) and in the soil seed bank (21 species) of the least transformed patch of thermophilous oak forest. It was decreasing gradually with increase of the tree canopy cover on the research plots. Our results indicate also that the higher the coefficient of similarity between seed bank and vegetation, especially of the ancient forest species, the higher the forest’s naturalness. We conclude that restoration of thermophilous oak wood has the highest chances for success in patches with well preserved seed banks and vegetation.
Species abundance-distribution relationship is currently a hot topic in community ecology. Previous studies have suggested that a positive abundance-distribution relationship is a widespread feature of ecological assemblage across a wide variety of organisms, but how this relationship varies among different functional groups remains unclear. In this study, the species abundance-distribution relationship in the tree layer, shrub layer, and herb layer were analyzed respectively in an oak forest (Quercus liaotungensis Koidz.), Beijing region, China. Ten transects were set up from the foot to the top of every west slope to create a continuous altitude gradient (1020– 1770 m). The width of each transect was 10 m and the length of each transect ranged from 80–200 m, depending on the altitude range and slope degree. This study area consisted of 119 quadrats, each 10 × 10 m2. Within each quadrat, three sub-quadrats (1m × 1m) were randomly selected for the inventory of herb layer. Our results showed that the relationship between local species abundance and the regional distribution was significantly positive while the frequency distribution was unimodal in the three layers, indicating that locally abundant species were widely spread whereas locally rare species had restricted regional distributions. Variance partitioning of species abundance showed that the contribution of environmental variation and spatial variation to regulating the species abundance-distribution relationship of different layers are different: the pure geographical variation decreased and the pure soil variation increased in the order of tree layer, shrub layer, to herb layer, while the response due to total soil variation was similar in all three layer communities. The distribution of tree layer and shrub layer are mainly influenced by large-scale factors while herb layer distribution is more likely determined by local-scale factors.
Traditional forest management as coppicing and coppicing-with-standard are recently considered as beneficial for biodiversity in woodlands. Cessation of coppicing leads to changes in stand structure and often loss of biodiversity. In contemporary Polish forestry coppicing is not applied, however some stands of coppice origin persist in Silesia until present. The overgrown coppice oak forests that cover the southern slopes at the foothills of the Sudetes Mountains (Silesia, Central Europe) are considered to be Euro-Siberian steppic woods with a Quercus sp. habitat (91I0): a priority habitat in the European Union, according to the Natura 2000 system. They support one of the largest populations of wild service tree (Sorbus torminalis Crantz) in Poland. In this study we investigated the relation of stand structure and trees parameters with environmental variables. The results showed considerable variability of stand volume, tree density and stems’ size correlated mostly with soil texture, but not nutrient content. We attributed it to soil dryness which seems to be the crucial factor controlling growth of trees. The natural regeneration of trees concentrated mostly on non-exposed sites on less acidic soils, but seedlings of wild service tree were present almost exclusively on most insolated sites, with shallow acidic soils. However, the regeneration of trees in sapling stage was restrained by browsing. Results suggest that maintaining of Sorbus torminalis requires protection against browsing, and some kind of active management is necessary to retain the observed stand structure with high proportion of wild service trees in stands on more fertile soils.
A second locality of Camponotus (Colobopsis) truncatus (Spinola), a Mediterranean dendrobiotic ant species rare in Central Europe is reported from Poland. Single workers were collected from trunks of old oaks (Quercus robur L.) in the Rogalin Oak Wood within the Rogahn Landscape Park (Wielkopolsko-Kujawska Lowland, Western Poland). At the same time, besides C. truncatus, one more rare ant species, Temnothorax corticalis (Schenck), is reported from the Wielkopolsko-Kujawska Lowland for the first time. A key to workers of the Polish species of the genus Camponotus Mayr is given.
There are 18 Quercus species in Turkey, and Quercus vulcanica, called “Kasnak oak” in Turkish, is an endemic species. The Kasnak oak has been studied in three localities where the well formed communities of this species exist. The evaluation of bioclimatic tolerance ranges of Kasnak oak in Turkey was the aim of the study. Overall results support that Kasnak oak prefers humid conditions in ambient habitat.
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