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The wild boar is an omnivorous animal, and by foraging (rooting) disturbs the top soil layer. In some regions of Poland and Europe seasonal fluctuations in rooting have been observed. Wild boars not only eat plants, but also strongly modify their habitat. In Białowieża National Park wild boar most frequently visit oak-hornbeam forests on fertile soil. On sites where the forest floor is covered with dense vegetation the germination of seeds is difficult, and wild boar rooting can promote the removal of diaspores from deeper layers of the soil seed bank. Within a 3-year observation on 30 subplots about 10,000 seedlings emerged representing 38 species. Our study revealed that rooted patches are characterised by a very rich and diverse flora of seedlings representing mostly forest species, but their density is low. The dominant species germinating in the disturbed ground vegetation is Urtica dioica, a species forming the persistent soil seed bank. There is a possibility that seedlings of herbaceous plants emerging on permanently rooted patches are of exogenous origin, since the seeds germinating there were in many cases damaged by repeatedly rooting animals and had no chance for further growth and reaching the generative phase. However, the soil seed bank in the rooted area has to be analysed to confirm this theory, that they have exogenous or endogenous origin. Seedling density in a repeatedly rooted oak-hornbeam forest is determined by factors other than those related to rooting. In this context the present study did not demonstrate a negative impact of rooting intensity on seedling emergence.
The process of forest fragmentation has been observed in many countries, where plant species had adapt to different habitats, such as for example manor parks and rural plantings. A number of scientists have studied the parks as sites where waning environments and landscapes find their shelter. In 2011–2012, research was undertaken on diversity of vegetation in afforestations of parks, rural plantings and oak-hornbeam forests in Sandomierz Basin. In order to compare the means obtained univariate analysis of variance (one-way ANOVA) was used with juxtaposing divided by each of the two criteria: size (the small, and large parks) and conservation(cultivated parks and nonclutivated parks). Tukey’s test was used to examine the significance of differences between respective groups. Analyses were with STATISTICA 9.1. software. Plants classified as forest species, grassland species and those of synanthropic communities were observed in all the afforestations. The parks with high wooded and not mowed areas and oak-hornbeam forests were more forest-like than other types of afforestations studied.
The aim of the present study was to determine how internal diversity of oak-hornbeam forest modifies the course and effects of infestation of small-flowered balsam (Impatiens parviflora) with rust Puccinia komarovii. The study investigated the effect of the disease on the demography of the population, and the habit and biomass allocation of the infested specimens, as well as the initiation of non-specific defense mechanisms. It was shown that: 1) the percentage of infected specimens was independent of the undergrowth-coverage rate and of the I. parviflora density; 2) infected populations differ from healthy ones in the seasonal dynamics of abundance changes; 3) high mortality is observed as early as May and the first part of June, i.e. it pertains to specimens, which did not begin reproduction; 4) the presence of infection and its intensity stimulate the growth of the stem and the hypocotyl; 5) fresh weight of infected specimens is by almost 30% lower in comparison to the weight of uninfected plants; the weight of badly infected plants decreases by 20% in comparison to the less severely infected balsam plants; the weight of generative organs drops most significantly, even by over 50%; 6) biomass allocation does not fluctuate considerably; 7) reproduction effort expressed by the ratio of the weight of fruits (or only seeds) to the total biomass shows a distinct downward trend; 8) the environmental factor does not affect the force of defense mechanisms, the strength of biochemical response of diseased plants depends on the degree of their infestation.
This study investigated the extend to which the snail Columella edentula is more strongly associated with the small balsam Impatiens parviflora than with other plants in the herb layer of an oak-hornbeam forest, and to interpret the character of the interaction Impatiens parviflora - Columella edentula. Numbers of C. edentula and rates of colonization were compared on various plant species under natural and laboratory conditions. Seasonal variation in snail abundance on I. parviflora was observed on permanent plots. The leaf injuries caused by C. edentula were localized in respect of the morphological and anatomical structure of leaves. The results show that I. parviflora is one of the plant species of the herb layer that are most abundantly colonized by this snail in oak-hornbeam forest. Snail finds a plant particularly suitable as a place for resting. The most favoured attachment site is on the underside of the leaf, along the midrib, which provides the highest and relatively stable humidity, as well as protection from direct sunlight and predators. I. parviflora is also a food for the snails, but they do not eat these fragments of leaves where calcium carbonate is accumulated.
Habitat selection of Collared Flycatcher, Ficedula albicollis (Temm.) was studied at three mountains of Continental Croatia covered with oak-hornbeam, beech and coniferous forests. Standard point count technique was used (n = 163). Collared Flycatcher territories were found at 59 points, 17 of them identified as the best territories, with two or more pairs present. Habitat at each counting point was described by the circular plot method. Each counting point was further characterized by the forest type. Differences between the proportions of available and used forest types were tested with χ² goodness-of-fit test. Standardized selection index (B) and 95% confidence limits with Bonferroni correction were calculated. PCA was used to identify the principal sources of variation in the habitat structure. In our study, both forest types and structural characteristics of habitat had effect on the habitat choice of the Collared Flycatcher. The Collared Flycatcher preferred oak and beech forests and strictly avoided pure coniferous stands. The best territories are mostly situated in the pure beech and mixed beech forests. PCA on habitat characteristics produced five components which accounted for 84.3% of the variation in the habitat structure. PC1 and PC3 indicated the presence of coniferous trees while PC2 and PC4 indicated the forest age. The PCA revealed significant relationship between Collared Flycatcher presence and several structural characteristics of habitat: total tree density, densities of small and large trees, shrub density and average tree basal area. The best territories were situated in the forest patches with low number of large trees. Tree density is an important factor for habitat selection in younger forests, but in stands older than 100 years, other factors play more important role in the habitat selection. The Collared Flycatcher avoided forests with dense shrub layer.
We studied an old growth deciduous forest seed bank to examine how its potential role in regeneration is shaped by natural forest environment. Our research questions were: is the spatial pattern of seed bank influenced by local variation in elevation, soil moisture and light intensity, and what is the impact of herb layer characteristics on seed bank pattern. We recorded species composition of the herb layer and seed bank on a 2 × 40 m study plot divided into 20 quadrates, situated in a natural oak-hornbeam forest, in the Białowieża Primeval Forest, (NE Poland). Soil cores were sampled from two soil layers (0–5 cm and 5–10 cm) yielding altogether 40 samples of a total 15.9 dm3 and 0.159 m². Seeds were extracted from soil samples under a microscope. Ellenberg indicator values were used to characterize light (L) and moisture (F) conditions. Relative quadrate elevation was averaged for nine points. There were 6.65 × 10³ seeds m⁻² in upper soil layer and 3.00 × 10³ seeds m⁻² in lower soil layer. Seed bank structure constituted of patches 6 m diameter in the upper soil layer and 4 m in the lower soil layer. Aggregated pattern of the seed bank was influenced by clumped distribution of plants in the herb layer. Seed bank species richness in the upper soil layer was correlated with moisture (r = 0.485, P =0.03) and light (r = 0.526, P = 0.0172) values. Seed densities were correlated with moisture (r = 0.848 P <0.0001 upper and r = 0.491 P = 0.0278 lower soil layer) and light (r = 0.803 P <0.0001 upper and r = 0.751 P = 0.0001 lower soil layer). Seed density in upper soil layer was negatively correlated with elevation (r =–0.485 P = 0.0422). Higher seed density and species richness of the seed bank associated with better light conditions and higher moisture is probably caused by higher seed production in favourable conditions, and factors promoting seed persistence in soil. Our results indicate, that even subtle changes in light, moisture and mean relative elevation can shape seed bank spatial pattern on a fine local scale, differentiating the response of this community to small scale disturbances present in natural forests.
The influence of the site factors related to soil, forest stand and litter as well as to altitude, exposure and slope - on the composition/abundance structure of millipede communities (Diplopoda) was estimated. The research was carried out in 1999 to 2002 in 13 mixed oakhornbeam forest stands in Malé Karpaty Mts. (South-Western Slovakia) ranged from 132 to 768 m a.s.l. In each locality, millipedes were collected by sieving of the litter taken at monthly intervals from 16 quadrates (25  25 cm) in each site. The redundancy analysis was applied. The most apparent influence on the community structure was ascertained for pH-value of litter and age of forest stand. Nitrogen content in litter was the most important factor, influencing the species richness of the millipede assemblages in studied sites.
Forest seed banks mostly studied in managed forests proved to be small, species poor and not reflecting aboveground species composition. Yet studies conducted in undisturbed communities indicate a different seed bank characteristic. Therefore we aimed at describing soil seed bank in an undisturbed forest in a remnant of European lowland temperate forests, the Białowieża Forest. We compared similarity between the herb layer and seed bank, similarity of seed bank between different patches, and dominance structure of species in the herb layer and in the seed bank of two related oak-hornbeam communities. We report relatively high values of Sorensen species similarity index between herb layer and seed bank of both patches. This suggests higher species similarity of the herb layer and soil seed bank in natural, unmanaged forests represented by both plots than in fragmented communities influenced by man. Although there was a set of core seed bank species present at both plots, yielding high Sorensen species similarity index values, considerable differences between plots in seed bank size and dominance structure of species were found, indicating spatial variability of studied seed bank generated by edaphic conditions. Dominance structure of species in the herb layer was not reflected in the underlying seed bank. This stresses, that natural forest regeneration cannot rely only on the seed bank, although some forest species are capable of forming soil seed banks. While forest seed banks may not reflect vegetation composition of past successional stages, they may inform on history and land use of a specific plot.
Population dynamics, space use and interspecific interactions of the forest dormouse Dryomys nitedula were studied for four years in an oak-hornbeam forest in the Białowieża Primeval Forest (NE Poland). Animals were captured with live-traps and marked by eartattooing. Population density ranged from 1.4 to 18.6 individuals × 10 ha⁻¹. Dormice reproduced in all years of study (2001–2004). Offspring were born in June and first juveniles were caught at the beginning of August. The last dormice were captured at the end of September. Three forest dormice (1 male and 2 females) were radio-tracked during first half of June 2001. Male home range area was larger (4.2 ha) than home range areas of females (0.75 and 0.73 ha). The longest distance between two consecutive daytime nest sites was 275 m for the male and 126 m for the females. Average home range length calculated from radiotracked individuals (218 m) was larger than the one from live-trapped dormice (93 m). Dormice used bird nest boxes and tree hollows for daytime nest sites. They preferred nesting in the nest boxes previously occupied by birds and they used old bird nest material for the nest construction. Home ranges of radio-tracked forest dormice overlapped widely with home ranges of fat dormice Glis glis. Most of live-traps used by the forest dormouse were also visited by the fat dormouse.
The aim of the studies carried out in the natural oak-hornbeam forest Tilio-Carpinetum typicum and in the degenerated form in the stage of pinetization Pinus-Lamniastrum, was to obtain and compare qualitative-quantitative structures of soil fungi communities in two different oak-hornbeam forests. This degenerated form of oak-hornbeam forest is the result of removing the natural tree population (typical oak-hornbeam forest) and re-afforesting the resultant vacant area with pines. The study plots were located in such a way that the variations of soil fungi communities were affected only by seasonal changes in the vegetation of the degenerated oak-hornbeam forest Pinus-Lamnias- trum. The soils in both study plots are typical forest grey-brown podzolic soils (Luvisols). The results of mycoiogical studies indicate significant differences between soil fungi communities in both oak-hornbeam forests, although similarities especially in species composition of 15 of the most abundant fungi species were also found. The differences are the result of changes in the floral composition of degenerated oak-hornbeam forest. In the past, when typical oak-hornbeam forest covered whole studied areas, the soil fungi communities were probably almost the same in both plots. The first change could have happened after the removal of the trees; the second, after the re-afforestation of the resulting vacant area with pines. The re-appearance of Tilio-Carpinetum typicum in its once occupied habitat causes changes in the soil fungi community in the degenerated oak-hornbeam forest.
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