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The organic matter produced and accumulated by plants is a crucial component in the ecosystems on environmentally disturbed sites. The aim of our study was to evaluate the influence of initial fertilising on the aboveground and belowground tree biomass of Norway spruce. The biomass amount, distribution and chemical composition were studied in a young spruce stand growing on an acidified mountain clear-cut tract. The fertilised trees accumulated a higher amount of tree biomass. They nonetheless showed lower concentrations of P, N, and K in some root compartments than control trees, which could be ascribed to a dilution effect. As for the aboveground compartments, no significant differences in element concentrations were proved.

The aim of the present study was to analyse the impacts of different logging intensities after five years from logging including non-logged, low (3.4 felled stems per hectare), medium (5.2 felled stems per hectare) and high (7.1 felled stems per hectare) treatments on stem density, basal area, canopy cover, and forest biodiversity indices. The study area was located in northern Iran. Data was collected on a set of 120 circular plots with 5 m radius from both non-logged and logging areas. Stem density, basal area, and percentage of canopy cover were measured. Biodiversity study was done by measuring two diversity indices including Simpson's and Shannon-Wiener's, two richness indices including Margalef's and Menhinick's and two evenness indices including Pielou's and Hill's indices. The results indicated that the treatment with the medium logging intensity was found to cause the highest amount of positive effects on stem density, basal area, and biodiversity indices. It is concluded that harvesting intensity should be limited to a medium level (approximately 5 felled trees per hectare) during each logging operation to improve forest biodiversity indices.

The present study has been done to evaluate the impact of pure ash stand and mixed stand with beech on the herb layer biodiversity and soil properties in the forests of Noor city. There is a unique stand of ash in the forests of Noor city and at 1,900-2,100 m a.s.l., which is rarely seen like that in the northern forests of Iran. Shannon-Wiener diversity indices (H'), Simpson index of dominance (D), Margalef richness (R₁) and Pielou's evenness were used to analyse biodiversity. Sampling was also conducted to investigate physical and chemical properties of soil (bulk density, acidity, electrical conductivity, soil moisture, soil lime, nitrogen and organic carbon) in each sample plot and at two depths (10 and 20 cm). The total number of 26 soil samples (13 soil samples at either depth) in pure ash stand and 24 soil samples (12 soil samples at either depth) from this type of stand mixed with beech were taken. The results of plant species biodiversity showed that between the pure ash stand and the stand mixed with beech there is a significant difference at the 99% probability level in Shannon-Wiener diversity, Margalef richness, and Simpson dominance. There is also a significant difference at the 95% probability level between the two stands under study in Pielou's evenness index. The results of soil factors also showed that at the depth of 10-20 cm acidity factor showed a significant difference from its adjacent stand at the 99% probability level. There is also a significant difference at the 99% probability level in acidity (0-10 cm) and soil moisture at the depth of 10-20 cm between the two areas, but there is not any significant difference between the areas under study in electrical conductivity and lime factors at the two depths and also in moisture content at the depth of 0-10 cm. It should be noted that between the stand and soil nitrogen, organic carbon and bulk density parameters at both depths (0-10 and 10-20 cm) a significant difference at the 95% confidence level is shown.

Taxocenosis of psocids (Psocoptera) was studied in the territory of the Drahanská vrchovina Hills in the Czech Republic. Representative research plots were selected in forest ecosystems with natural species composition and spatial structure (small-scale strictly protected areas) as well as in forest ecosystems with altered tree species composition and spatial structure. Research was conducted in three altitudinal vegetation zones (AVZ): in 2^nd communities of Fagi-querceta s. lat. (beech-oak forests), 3^rd Querci-fageta s. lat. (oak-beech forests) and 4^th Fageta abietis (beech forests with fir). Research plots are situated at altitudes ranging between 275 and 540 m a.s.l. In the 2013 growing season, totally 3,474 imagoes and 2,532 nymphs of 32 psocid species were collected. Of those, 748 imagoes of 25 psocid species were collected in Fagi-querceta. The occurrence of Caecilius burmeisteri, Caecilius flavidus and Graphopsocus cruciatus was eudominant. 2,194 imagoes of 23 psocid species were found in Querci-fageta, eudominant were there Caecilius flavidus and Caecilius burmeisteri. 532 imagoes of 18 psocid species were found in Fageta abietis, eudominant were there: Caecilius flavidus, Peripsocus subfasciatus and Caecilius burmeisteri. In respect to the species composition, 3^rd AVZ and 4^th AVZ are similar to each other while 2^nd AVZ is less similar.

The aim of the study is to evaluate the role of the Grand fir (Abies grandis [Dougl. ex D. Don] Lindl.) as a soil-improving species in the area of the University Training Forest in Kostelec nad Černými lesy, Jevany district. The state of humus forms in the stand part with Grand fir was compared with the mature Norway spruce (Picea abies [L.] Karst.) without regeneration, with young beech (Fagus sylvatica L.), Norway spruce (Picea abies [L.] Karst.) and oak (Quercus spp. L.) stands (all of pole stage). The site is characterized as 4P1 - acid oak-fir site with Luzula pilosa, the geological bedrock is formed of cretaceous sandstone with loess overlays, the soils are Luvisols, the terrain is flat at the altitude of 420-440 m a.s.l. The humus form samples (L, F, H, Ah horizons) were taken in 4 replications, quantitatively for the holorganic layers. The dry mass amount and total nutrient contents were analyzed for holorganic horizons, the basic pedochemical characteristics (pH, soil adsorption complex characteristics, exchangeable acidity and exchangeable nutrients) were determined for all horizons. The results confirmed marked and positive effects of the Grand fir litter on the surface layer characteristics. This tree species supports the litter of good composition, transforming easily and forming humus forms of higher quality compared to coniferous as well as studied broadleaved species.

The study focuses on selected forest site units on water uninfluenced sites on limestone in Bohemian Karst. The species composition of phytocoenoses, their potential production and soil properties were assessed. Studied forest site complexes are correctly determined and they provide important information from the aspect of planning and practical nature conservation management. It is necessary to specify the criteria of categoria calcaria in detail, since it is often difficult to distinguish it from categoria mesotrophica. Water retention capacity of soils, a criterion often neglected so far, presents a useful view of forest site water budget and it is a suitable criterion in forest site classification.

An assessment of soil compaction caused by machinery used in stump and/or logging residue extraction for energy on soils typical of Ireland. We determined unaffected soil conditions and to find the compaction grade after timber harvesting and bundling activities, and to compare those results with stands where timber harvesting was followed by stump extraction for energy. The investigation was carried out in Ireland on three different locations which had a slightly different proportion of stones in their soils. Two of the soils were purely mineral soils, and the third was a mineral soil affected by anthropogenic activities. To ensure comparable results as much as possible, the moisture content of the soil on wet basis was investigated. Each location was purposely treated. Therefore, on each location plots were identified as follows: plots unaffected by operation (reference area), plots after timber harvesting, plots after timber harvesting and bundling operation, and plots after timber harvesting and stump extraction operation. According to the experimental design 40 repetitions on each of the three different treatments were set. The results showed that the compaction of soil occurred on plots after timber harvesting, but there was not a significant difference between compaction grades with and without logging residue bundling operation. However, once the site was extracted of stumps, the soil became too loose and no significant difference was found compared to unaffected soil.

Adapting forests to climate change involves silvicultural measures such as use of a range of species and the fostering of mixed stands. We tested these in a Sitka spruce forest in southern Scotland, employing the Ecological Site Classification to match suitability of 24 species to six climatic and edaphic variables under values of accumulated temperature and moisture deficit projected for a medium emissions scenario for the present century. Both median and 90^th percentile values were contrasted. In the first case there was a small change in species suitability with Sitka spruce, noble fir, downy birch, sycamore and aspen being the most suitable species. When the 90^th percentile values were employed, the suitability of Sitka spruce and similar conifers had declined by the 2050's due to soil moisture deficits. The actual performance of a range of species in a long-term experiment on a similar, warmer site showed several productive conifers including Sitka spruce that maintained reasonable growth when planted in mixture. Mixed plots were developing into pure stands of the most productive species. Species diversification was the most practical adaptation measure for this forest and should concentrate on areas of the greatest risk like south-facing slopes with free-draining soils.

The main goal of work was to compare the flight activity of Trypodendron lineatum, T. domesticum and T. laeve in Central Europe. Field trapping experiments were conducted in 70- to 100-year-old Norway spruce stands located at three study sites in the Czech Republic. At each study site five pheromone traps were used. Pheromone-baited, black, window-slot traps (Theysohn, Germany) were used. Traps were placed at log landing areas 10-15 m apart from the nearest forest edge. Each trap was baited with a standard synthetic pheromone lure, XL Ecolure (Fytofarm, Slovakia). Three species of Trypodendron were recorded. T. lineatum was the most abundant, followed by T. domesticum and T. laeve. Flight activity began at the end of March or in mid-April. Only one another peak of the flight activity of T. lineatum and T. domesticum was observed at one study site in May 2011. Statistically significant relationships were found between catches of all species with the exception of T. lineatum vs. T. laeve and T. domesticum vs. T. laeve at one site. Males were more abundant than females mainly in T. lineatum samples. On the other hand, T. domesticum and T. laeve abundances of males and females were more equal, but in all cases of all Trypodendron species these abundances were not significantly different at all sites.

The most common way of pedunculate oak regeneration on the floodplain sites in the Czech Republic is artificial regeneration by clear-cutting. However, what is the real potential of natural regeneration of pedunculate oak? In our research object (3,355 ha of floodplain forest in the southern part of the Czech Republic - Zidlochovice region), we inventoried about 8 ha of successful natural regeneration of pedunculate oak with density ranging between 15,000 and 100,000 individuals per ha on the plots after final cut. All harvested oak dominated parent stands showed a lower stock density that ranged between 0.5 and 0.8. In the next analysis of the survival of oak natural regeneration spontaneously established in different light conditions under the shelter of parent stands we observed the highest occurrence of saplings closer to the forest edge. A sufficient density of regeneration (above 10,000 individuals per ha) was found at the distance up to 18 m from the edge, where more than 24% of direct and 30% of indirect site factor were discovered. In the stand with the full canopy closure (DSF about 10% on average and ISF about 24%) the oak regeneration is missing and was replaced by other tree species (especially ash and field maple). In the examined area the natural regeneration of pedunculate oak should be one of the possible alternatives of floodplain forest regeneration if certain conditions are met.

The issues related to appropriate management methods of beech stands have been considered as a crucial topic from the past up to now. Although the positive effect of tending on wood quality in beech stands is a generally known fact, the results from long-term experiments are very scarce. We investigated the qualitative production of beech forests, treated by different thinning methods during a long-term period of 53 years. For this purpose two long-term (lasting 53 years with a measurement interval of 5 years) series of research plots were used. On each plot three different thinning methods were applied: i) heavy thinning from below (C-grade according to the German forestry research institutes in 1902), ii) free crown thinning (original thinning method developed in Slovak Republic), and iii) control plot (without treatments). As much as 6,316 trees at the beginning of research and 864 trees at the last measurement were assessed and measured. Chi-squared test was used to quantify the effect of different thinning methods on qualitative wood production. The results showed the highest proportion of target trees, as well as the best average quality of the stem and crown on plots where the free crown thinning was applied followed by the plots with heavy thinning from below and control ones. We found that the proportion (expressed out of the total growing stock of crop trees) of veneers was the highest on plots managed by the free crown thinning (30 and 36%) and the lowest on control (unthinned) plots (10 and 19%). It is concluded that no significant differences between the two studied sites were found, which demonstrates a similar effect of the investigated thinning methods at different places across the region of Slovak Republic, but with similar site conditions. On the other hand, the most appropriate and hence successful thinning method was proved to be the free crown thinning, which is also recommended for management of beech forests from the aspect of silvicultural wood quality.

Density of regeneration in European subalpine Norway spruce (Picea abies) forests is typically low with regeneration primarily located on dead or decaying wood. The post-disturbance development of this regeneration is crucial for natural forest succession. The aim was to identify the influence of disturbance on regeneration on decaying logs immediately after a severe disturbance event. Study plots were established in two subalpine spruce forests: the first, an undisturbed site located in the Hrubý Jeseník Mts. and the second site in the Šumava Mts. that has experienced recent severe disturbance. Regeneration density increased between 2008 and 2011 by 7% (0.29 individuals per square meter of log) at the undisturbed site and by 33% (3.24 individuals per square meter of log) at the disturbed site. The increased regeneration density observed at the disturbed site was mostly associated with the smallest saplings. The highest increase in regeneration density was observed on logs with the largest diameters. Three years after severe disturbance caused 100% mortality of the parent stand in the Bohemian Forest, no significant effect was recorded on the growth rate and survival of established spruce saplings on dead wood.

Traditional land use has shaped the Mediterranean region for a long time and has resulted in present-day complex landscapes. The land abandonment dating from the 19^th century at a site located in the southwestern Alps (France) makes it possible to analyse how present-day forest stands inherit from past land uses. Tree composition and tree age structure were analysed in three stands resulting from different former land uses, i.e. ancient coppice, formerly grazed area and formerly tilled area. The ancient coppice contains the densest tree cover and is dominated by Fagus sylvatica, whereas the formerly ploughed and grazed areas are less dense, both dominated by Pinus sylvestris. Forest stand in the ancient coppice is older than in the formerly grazed area, and forest stand is the youngest in the formerly ploughed area. These stand differences are largely explained by former land use and the abandonment process. Albeit strong changes result from the land abandonment, these landscapes inherit aspects of their land use during the 19^thcentury at least and the dynamics does not match the expected pattern of soil fertility.

Northern red oak (Quercus rubra Linnaeus) is a promising species which could help to mitigate the sanitary problems. Northern red oak is also a commercial species and offers many environmental services. Northern red oak prefers rather dry acidic sites commonly found in Bohemia. The literature confirms that the species is quite fertile but acorn production is highly variable. Northern red oak seedlings develop a long tap root during their first year, which enhances their survival and performance. Different silvicultural systems are proposed and pros and cons are discussed in this review including their influences on forest floor and soil.

Road cross section, as one the main effective factors in relation to fill and cut volume, was effective in costs and disturbance of forest road constructions. In this research, the effect of a few physiographic parameters on forest road cross section was evaluated. For this purpose, 192 cross sections on forest roads were delineated selectively in mountain forests in the north of Iran. The physiographic factors including elevation, hillside slope, slope aspect, rock base, and soil texture as well as cross section width were measured. After evaluating the data in terms of normality and homogeneity, it was analysed by Spearman's and Pearson's correlation tests using SPSS20. One-way ANOVA, two-way ANOVA, and Duncan grouping tests were used to determine the effect of the above-mentioned factors both separately and simultaneously. Results showed that the parameters including hillside slope, rock base, and soil texture had a significant effect. Elevation was recognized as a regional parameter due to the lack of any relationship with cross section. There was no significant relation between slope aspect and cross section. The hillside slope was defined as the most effective parameter on the cross section.

European ash (Fraxinus excelsior) and sycamore maple (Acer pseudoplatanus) are considered amongst tree species as some of the most attractive forage for red deer (Cervus elaphus). The aim of this paper is to estimate branch and foliage mass browsing by red deer in young Sycamore maple and European ash in Central Slovakia and to analyze interspecific differences in browsing frequency and quantity. Altogether 665 ash trees and 701 maple trees were measured for height and stem diameter at the ground level. Red deer browsing, defined as leader shoot or lateral branch cropping, was recorded for all trees. A combination of the diameter of browsed branches and branch regression models allowed for the estimation of browsed (potentially consumed) mass by red deer. Results show that browsing occurred more frequently on maple (5 cases per tree) compared to ash (3 cases per tree); however, more total branch biomass was consumed in ash (10.7 g per tree) compared to maple (2.6 g per tree). This is because browsed branches were larger in ash than in maple. We assume that the difference in the size of browsed branches between ash and maple is relative to species-specific branch morphological and structural features.

Preference of biotopes and selection of food by wild herbivores are more complicated in a cultural landscape used for agriculture than in natural conditions. Agricultural management significantly affects the feeding as well as cover conditions of the environment and changes in quality and accessibility of food sources occur throughout the year. We studied the consumption of agricultural crops and impact on tree shoots by herbivores in a mosaic landscape. Large herbivores utilized the food supply on the lands outside the forest environment during winter and early spring and in summer. In summer the cereal grains were preferred by herbivores and accounted for a significant share in their diet. The intensity of shoot browsing differed between the localities and between the studied woody species but was not lower due to the presence of attractive crops near the forest. The utilization of food outside the forest may help the animals to survive the winter but the potential of this food for reducing tree browsing in the forest is low.

The Alpine ecosystem is very sensitive to climatic changes, which have an influence on glaciers, snow, vegetation and soils. The aim of this review is to illustrate the effects of global change on the Alpine soil ecosystem, which is an optimal marker to record them. The manuscript enhances our understanding of the global change effect on the Alpine environment: on morphology, on ice, on vegetation and points out how the cycles of soil nutrients equilibrium have been changed with a direct effect on soils that support plant species. The changes in cryosphere, glacier reduction and periglacial environment as glaciers retreat, decrease in the snow cover extent and earlier snowmelt, determine an effect on soils (on the structure, organic matter and humus forms, soil processes and soil types) from the top of the Alpine horizon to the bottom. The processes induced by climate change (such as erosion and tree line shifting) have a direct effect on water balance that can be observed on soil profile characters with an effect on upward migration, change in phenology, extensive losses of species. The equilibrium of the biogeochemical cycles has been changed and this has a direct effect on soils that support plant species.

Forests in the mountain ranges are supposed to meet multiple objectives at the same time. There are different expectations and priorities among stakeholder groups. The object of the research is the case study area in the Goat Backs Mountains in Slovakia (representing Western Carpathians). The stakeholders' panel which included local government officials, landowners, foresters, interest group representatives etc. judged the current and future importance of ecosystem services in a special questionnaire. The context analysis provided main strengths and weaknesses, threats and opportunities that influence mountain forest management and the provision and use of ecosystem services in the case study area were done by involved experts from practice and science. Based on the SWOT results a possible strategy for the provision of ecosystem services was proposed. Some of the key issues that have been identified by experts concerning the balancing of ecosystem service provision are: strengthening the local stakeholder involvement; enhancing regional initiatives; and economic market-oriented instruments and economic incentives.

The work presents the results of phenological observations of flowering and fruit ripeness of the European hazel (Corylus avellana L.) in Slovakia in two time periods: 1964-1983, and 1994-2013. The phenological stations at elevations from 100 to 875 m a.s.l. were grouped to 7 elevation zones, each 100 m wide. In the first studied period, flowering started on 19 March on average, while in the second period it started 5 days earlier. The average duration of flowering equal to 7-9 days did not depend on the elevation, but on the air temperature and weather patterns in the different elevation zones. During the first period, the average elevation gradient of flowering was 5.6 days per 100 elevation meters, while in the second period it was reduced to 3.5 days in the entire elevation profile. In the elevation zones between 300 and 500 m, a high correlation (P < 0.01) between the onset of flowering and elevation was reduced to a moderate level of correlation due to changing environmental conditions. In 1994-2013, the ripeness of hazel nuts started on average on 30 August in Slovakia, showed low variability and moderate correlation with elevation. The phenological elevation gradient was 2.9 days per 100 m of elevation.

The contribution presents the results of a 5-year (2008-2012) dendroecological research in a Norway spruce (Picea abies [L.] Karst.) clone forest (Northern Slovakia). Due to different climatic and soil moisture conditions in the monitored years, different seasonal courses of stem increment formation were observed using band dendrometers with continuous data recording. The lack of precipitation affected growth processes mainly during the growth culmination and at the end of summer. The multiple regression analysis of the impact of individual factors on stem circumference changes on the basis of their partial correlation coefficients revealed that the individual environmental characteristics influenced daily stem radial changes with time lags of one to ten days. The results of the analysis of variance showed that the stem radial reactions to climatic and soil moisture factors were not significantly different between the clones.

Assemblages of earthworms were evaluated in spruce and beech stands in the Kienhaida Nature Reserve (Krušné hory Mts., Czech Republic) and its immediate surroundings, where site conditions were modified by the soil preparation for forest regeneration. The beech stands of the reserve showed low diversity but higher earthworm abundance than did the spruce stands, which in turn showed the lowest Lumbricidae abundance (18 individuals.m^-2). The highest abundance of earthworms (124 individuals.m^-2) was found in the soil of mounds created 30 years prior to sampling from the organic soil of the A_h horizon. The highest species diversity and low abundance were characteristic of areas between the mounds, the soil surface of which was greatly disturbed after removal of the A_h horizon to create those mounds. The degree to which the reforested clear-cuts created due to air pollution were overgrown with weeds contributed positively to the diversity and abundance of Lumbricidae.

To keep forest soils fertile, forest practitioners plant mixed stands that are composed of both economically efficient trees such as conifers and soil-improving broadleaves. This is a mandated practice in the Czech Republic. As the new forest grows, it creates a dense canopy. The canopy is a principal source of organic matter to the forest soil. The formation of new forest humus is particularly important in first-generation forests on the former agricultural soil. Former meadow is a suitable site for forest floor and soil investigation since forest-floor humus covering the surface of the soil is a completely new layer. Both pure evergreen conifer and mixed treatments were planted in 2001. The experimental plot was established in order to investigate performance of tree species and restoration of forest-site conditions. We sampled dead-plant material and 0-10 cm topsoil to investigate their properties under the 10-year-old stands. We compared the treatments by descriptive statistics using both univariate and multivariate techniques. Dry mass (medians of weight) varied among the treatments from 11 to 19 Mg.ha^-1. The forest floor nutrient concentrations appeared to be dependent on the presence of admixed deciduous tree species (sycamore maple, small-leaved linden and European larch) as these forest floors (EL1, EL2, NS3, SM) were higher in base cations and phosphorus compared to pure spruce (NS1, NS2) and pure Douglas fir (DF) treatments. The first axis of PCA ordination plot revealed 45% of total variability and showed a clear distinction between evergreen coniferous and mixed species treatments. Young plantations produced forest floors of different quality; however it was not reflected in the topsoil properties.

This article summarizes basic estimates of productivity and trend analysis of one of the principal introduced forest tree species in the Czech Republic, i.e. Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco). As a comparison, we also examine grand fir (Abies grandis [D. Don] Lindl), northern red oak (Quercus rubra L. syn. Quercus borealis Michx.) and black locust (Robinia pseudoacacia L). This paper presents estimates of forest land area, standing volume, annual and total increments, distribution of age classes, average ages and site indexes for the period 1979-2010. All data were obtained from the national forest inventory of the Czech Republic. Korf's growth function was used for the assessment of current and mean annual increments (CAI, MAI) of Douglas-fir compared to other tree species. Our results suggest a decline in the annual area afforested by Douglas-fir, as influenced by the State administration management choices, a low rate of an increase in the forest land area, increasing average age of the forests. On the other hand, we observed a dramatic increase in the standing volume as well as high annual increments in volume. Douglas-fir is the most productive major tree species in the Czech Republic and there is a great potential to expand its use throughout the country.

The onset and course of selected vegetative phenological phases of beech along the altitudinal gradient in Slovak Republic were studied. Observations were done in the Burda Mts. (200-300 m a.s.l.), Kremnické vrchy Mts. (500 m a.s.l.) and in the Poľana Mts. (900-1,000 m a.s.l., 1,200-1,400 m a.s.l.). Selected spring phenological phases (budburst and leaf unfolding) as well as autumn phenological phases (autumn colouring and leaf fall) were investigated over the period of 5 years (2007-2011). The earliest onset of spring phenological phases during the period of study was found at the lowest-lying sites in the Burda Mts. By contrast, the latest one was observed at the uppermost site in the Poľana Mts. The dynamics of autumn phenological phases had the opposite course compared to spring phenophases. The earliest onset, observed in the uppermost locality in the Poľana Mts., was gradually delayed with decreasing altitude. The phenological gradient, expressing a shift in the onset of spring phenophases along the gradient, reached the mean values of 2.83-3.00 days per 100 m of an increase in altitude. In the case of autumn phenological phases the gradient ranged from -1.00 to -1.78 days per 100 m. On average, the growing season of beech lasted from 128 to 181 days along the altitudinal gradient. Significant correlations (P < 0.001) were calculated between the date of the onset of phenophases and altitude.

The quantification of stems (under- and overbark), foliage and fine roots in 14-year-old stands of European beech and Norway spruce grown on the same site were evaluated. Therefore, 60 trees of each species were sampled, dry masses of stems and foliage were established and expressed by allometric equations with stem diameter as an independent variable. The spruce allocated a much larger portion of biomass into the foliage than beech. The equations on a tree level were constructed also for specific leaf area and one-sided projected leaf area. Moreover, the quantity and morphological characteristics of fine roots in both stands were surveyed through soil coring. While standing stocks of fine roots were similar in the stands of both tree species, significant interspecies differences occurred in morphological properties of roots. Growth efficiency, expressing annual stem production on a variety of foliage and fine root parameters was calculated. The largest differences, specifically fivefold in favour of spruce, were found in growth efficiency based on a number of root tips.

The serious oak decline was reported for the 1979-80 period and 63.0% of adult oaks died in a mixed oak forest in the Síkfőkút site, Hungary. The data were used to obtain (1) quantitative information on diversity indices of shrub layer and shrub canopy, including foliage cover percentage of the shrub layer, mean cover of shrub species before and after the oak decline and (2) structural information on shrub basal area and shrub foliage arrangement. Since 1972 we have determined diversity indices, cover percentage and basal area of shrubby vegetation on the monitoring and plus plots. A negative relation was detected between Shannon-Wiener and Evenness indices of the shrub layer and living oak tree density. A positive relation was confirmed between basal area and mean cover of dominant woody species (Acer campestre, Acer tataricum and Cornus mas). The mean cover of shrub species except of A. campestre increased non-significantly after the oak decline on the 48 m × 48 m plot. The findings of the study indicate that diversity indices of the shrub layer and mean cover of A. campestre can be used as a principal indicator of natural disturbance in the studied mature stand and the species of the shrub layer respond differently to the decreasing stand density.

The paper presents results of an assessment of needle age classes in Scots pine partial populations in the period of three and five years after outplanting in a lowland site in relation to conditions created by climatic elements. The method is based on Skuhravý's (1987) description when the state of needle age classes of the third whorl (from the apex) is evaluated just once. Five-year summary of meteorological data was assessed according to the criteria of determination of periods of heat waves and dry spells. Differences in numbers of living needle age classes in the groups of Scots pine populations in the period of three and five years after their outplanting in permanent lowland sites proved the highest total number of living needle classes in the group of local lowland populations. On the contrary, the lowest total number of living needle classes was found out in the group of mountain populations. Critical climatic periods are overlaps of heat waves and dry spells that illustrate the complexity of moisture and temperature conditions of lowland sites. Although the Scots pine is a xerophytic species, it responded to the cumulation of adverse factors by accelerated needle senescence. Its physiological response to heat and dry stress consists in needle shedding, i.e. reduction in the assimilating area. As mountain populations are not usually exposed to heat waves, the impact of this phenomenon on them was the highest. On the other hand, the local (lowland) populations carrying information on the patterns of local climate from the reproduction period do not undergo any marked reduction in needle age classes.

The pine stand in the Havraní Skála locality in the Bohemian Switzerland National Park was affected by an extensive mixed-severity wildfire in summer 2006. The fire severity, fire type and fire extent were assessed by various fire severity measures collected in the field (mean bole char height on stems on sample plots, content of oxidizable C and total N at a soil depth of 0-5 cm), as well as by classification and filtering of green canopy cover from time series of aerial photographs acquired before the fire (2005), soon after the fire (2006) and one year after the fire (2007). The specific image analyses made it possible to uncover the spatial and temporal pattern of the stand defoliation. The central part of the site was mainly affected by the crown fire and thus defoliated substantially right during the fire. On the contrary, the peripheral part of the site was mostly affected by low-severity ground fire and therefore defoliated progressively one year later. All the fire severity measures used were well related.