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We studied sessile oak (Quercus petraea) growing on six dry sites to understand adaptability responses to drought stress. Pedunculate oak (Quercus robur) on a moderately dry site was tested in parallel. We analyzed accessions from mostly dry sites that were less sensitive to soil drought and found that the growth performance ranking was not the same before and after treatment. We used phenological plasticity approaches to study seed development and plant development before and after drought: the treatments included stem length, root length, and collar diameter, as well as dry above- and below-ground biomass performance. Additionally, after drought treatment, osmolytes and root surface were tested in Q. petraea. According to the analyses and results, the ranked sites did not maintain their ranking status, with Q. petraea exhibiting different rates of growth during each developmental stage from seed development until the end of the treatment of plant material. The smallest seeds came from the driest site, which may indicate more adaptability to drought stress. After drought treatment, large differences were found between the dry biomass performance, stem length, root length, and collar diameter of oaks grown on different sites. The osmolality of Q. petraea on most of the dry sites was higher under the reduced treatment than under the optimal treatment, but not significantly. After drought treatment, all accessions - and especially those from the driest site - showed large differences in growth performance between the treatments. The relationship between seed weight and seedling development before and after drought treatment differed according to the developmental stage.

Almost 24% of the Ukrainian Carpathian ecosystems are assigned to the conservation fund due to their ecological values and attraction to numerous tourists. The forest litter in mountain forest stands plays an important role in terms of its ability to mitigate the impact of tourist activities, and erosion processes along with its contribution to the soil mineralization. Water interception, infiltration, and retention ability of forest litter have an impact on hydrological processes of forest ecosystems. At the same time, the accumulation and spatial distribution of litter can be affected not only by environmental conditions, but also by tourism. In this study, 13 Norway spruce (Picea abies L.) stands distinguished by average distance to the trail were chosen to investigate whether there are any differences in litter structure, water retention, and infiltration abilities as well as litter accumulation in areas along popular hiking trails in the Ukrainian Carpathians. Results showed that the litter thickness has increased with altitude and slope steepness. Moreover, results of one-way ANOVA demonstrate a significant difference (P < 0.05) in litter stock between two groups of sample plots: established directly to adjoin hiking trails and at a distance. Therefore, the forest litter stock nearby hiking trails may indicate that trampling caused by tourists has a negative impact on litter accumulation. However, no statistical difference was found (P > 0.05) in the accumulation of litter along three trails and altitudes across all surveyed forest stands. Results of the immersion test showed that the litter infiltration rate has a significant negative correlation with the maximum mass of absorbed water (r = -0.62, P < 0.05), litter stock (r = -0.69, P < 0.01), and retained precipitation (r = -0.62, P < 0.05). Despite our assumption, the infiltration rate was lower for sites distanced from the hiking trail in comparison with adjoining ones. According to our measurements, the water holding capacity of the litter varies from 42.3 t.ha^-1 to 187.3 t.ha^-1 regardless of the stand composition. Further, the precipitation amount retained by litter varies between 4.2 mm and 18.7 mm. Insignificant differences in litter fractional structure and accumulation were observed in pure spruce stands and mixed spruce-beech with an admixture of beech up to 20%. Further observational and modelling studies are necessary to clarify the role of the beech share in stand composition in relation to fractional structure and water interception and retention ability.

Forests play a significant role for maintaining the biodiversity. In order to manage sustainable forests, tree species history, distribution, and their future prospects are vital. Using standardized quantitative approaches, the age, radial growth, and size class distribution of Abies pindrow (Himalayan fir) were determined from three different altitudinal sites (i.e. high, middle, and lower). The results indicate that Himalayan fir growing in the high-altitude site (Ayubia, 2 917 m a.s.l.) of moist temperate forests of the Himalayan mountains showed lower radial growth (0.13 cm) than in the middle (Bara Gali, 2 617 m a.s.l.; radial growth = 0.13 cm) and lower (Kuldana, 2 455 m a.s.l.; radial growth = 0.22 cm) altitude sites. Correlation analysis demonstrated that age showed a significant positive correlation (P < 0.001) with diameter at breast height. The tree-ring width chronology (totally 80 core samples) of Himalayan fir was developed from moist temperate forests of Himalayan mountains of Pakistan. At Ayubia site it possesses a long time-span (1703-2020 C.E.), followed by Bara Gali (1862-2020 C.E.) and Kuldana (1864-2020 C.E.). Further, the tree-ring width (TRW) chronology of Ayubia showed a significant positive correlation (P < 0.05) with May and June temperature, and a significant negative correlation (P < 0.05) with June and October precipitation, indicating that summer temperatures are the key factor for the radial growth of Himalayan fir. For the Kuldana site, the response of TRW chronology to temperature and precipitation was the same, however, it was significant only for June temperature at Bara Gali. The size class distribution of the high-altitude region (Ayubia) showed a higher number of individuals than the lower altitude region, indicating the lowest disturbance conditions. The absence of individuals in the early size classes and the gap in middle and mature size classes indicate a lower regeneration potential and anthropogenic impact. The pointer year analysis indicated that the Bara Gali forest is more sensitive to abnormal climate events than the other sites. Based on the present study, we suggest that proper attention and conservation strategy should be provided to Himalayan fir growing in the moist temperate forests of Pakistan.

The success of forest and agricultural plant establishment program mainly depends on the quality of reproductive material. The study intends to offer engineers and farm owners a solution for small-size seed improvement before sowing. The effect of low-intensity coherent light on the seeds of various crops is theoretically and empirically hypothesized. The seedlots of Scots pine (Pinus sylvestris L.) and sugar beet (Beta vulgaris L.) of Russian diploid hybrid RMS-127 were germinated in a controlled environment. The germinants were produced from six seed fractions, previously irradiated with 1.274 W.m^-2 at the 632.8 nm wavelength with 1, 2, 3, 5, 10, 15 min exposure to a standard laser system, plus untreated control. Pine germinants were measured on day 15, beetroot on day 10 after germination. An increase in exposure time reduced Scots pine germination energy and capacity, while for sugar beet the results were not conclusive. On the contrary, increasing the exposure time had a positive effect on both the height and biomass growth of both Scots pine and sugar beet germinants. The 10-min exposure time resulted in maximum values for sugar beet height and biomass and Scots pine height, while the 15-min exposure time produced maximum Scots pine biomass.

Control and supervision activities in the field of forest management are a type of activity of state authorities to detect, prevent forest violations. The purpose of this study is to analyse the dynamics and nature of violations in the forest sector on the example and in comparison of such regions of Russia as the Krasnodar territory and the Republic of Bashkortostan. The research methodology is selected taking into account the characteristics of the object under study. With the assistance of employees of the environmental inspectorate, search operations were organized in the areas where the greatest amount of forest damage occurs in the studied regions. The authors concluded that one of the reasons for the existing problems is the lack of interest of the state in the development of this sector of economy. The paper focuses on specific types of forest violations and the problems of their prevention. The authors believe that illegal logging belongs to the most common and socially dangerous forest violations. The article concludes that when adopting new regulations for control and supervisory activities in the field of forest management, the legislator must take into account requirements of administrative reform, regulatory guillotine, and risk-based approach.

The study focused on natural regeneration of European beech (Fagus sylvatica), Norway spruce (Picea abies) and European larch (Larix decidua) within very small and four times bigger size gaps following a disturbance at a mixed temperate forest in the Czech Republic. In spring 2013, experimental gap design starts, when 1 m2 circular sampling plots along transects were delineated within four selected naturally occurring canopy openings with size below 20 m2. In December 2013, these initial canopy openings were artificially enlarged by felling to 226 m2 for small and 904 m2 for big gaps. Regeneration was monitored in the next two consecutive growing seasons after disturbance. Light conditions were measured before and after disturbance. Results indicated that four times larger gaps increased twice levels of light conditions, and that diffuse light starts to equilibrate to direct light there. Large gaps were favouring larch regeneration. Beech regeneration was predominant, independently on gap size as the study area belongs naturally to Beech Forest Vegetation Zone, however, the decline of spruce regeneration was presumably linked to drought. Gap size explained variation of larch regeneration in gaps. Contrarily, gap size could not be associated with the prolific regeneration of beech and abysmal regeneration performances of spruce in gaps.

Biomass nutrient loss and retention were studied at nutrient-poor forest site dominated by Scots pine where two methods of logging residues handling after clear-cutting were compared. The experiment was conducted on nutrient-poor pine-oak forest site on deep sandy-gravel unconsolidated sediments at the altitude of 255 m. There were three treatments established such as (i) control - no harvesting, (ii) whole-tree harvesting with ca. 10% of the slash retained unintentionally on site as processing residues and (iii) stem-only harvesting when small-diameter wood and slash were left on site. The third treatment was found to retain much larger amounts of nutrients in logging residues representing 16% of total above-ground dry mass which accounted for 58% of N, 32% of P, 56% of K, 22% of Ca and 28% of Mg left on site.

The first competitive open tender called "Standing timber sale" was executed in 2010. The aim of the paper was to conduct complete collection of data from online tender catalogues and to analyze the data with respect to the coniferous/broadleaved ratio. A total of 254 units were analyzed, 195 of them harvested and 59 withdrawn from the auction at a limit price. Out of the harvested units, 125 units with a maximum 10% coniferous or broadleaved tree representation were selected, while the remaining 70 units showed a varying coniferous/broadleaved ratio ranging from 11% to 89%. Upon 0-10% coniferous ratio the average winning price ranged between 330 and 2,045 CZK.m^-3. Upon 91-100% coniferous ratio the winning prices ranged between 766 and 1,743 CZK.m^-3. The results obtained indicated a statistically significant difference between the average winning prices in stands with more than 90% conifers and in stands with more than 90% broadleaved species.

To minimize the cost of logging, it is necessary to optimize the road density. The aim of this study was to determine optimal road spacing (ORS) in Northern Austria. The stepwise regression method was used in modelling. The production rate of tower yarder was 10.4 m³/PSHo (Productive system hours) and cost of 19.71 €.m^-3. ORS was studied by calculating road construction cost, installation cost and yarding cost per m³ for different road spacing. The minimum total cost occurred at 39.15 €.m^-3 and ORS would be 474 m assuming uphill and downhill yarding. The optimal road density and yarding distance are 21.1 m.ha^-1 and 90 m, respectively. A sample logging area was used to plan different roads and, using network analysis, the best solution was found based on a modified shortest path algorithm. The network analysis results were very different from the optimal road spacing results that assumed roads and logging corridors could be located anywhere in the planning area at a constant cost. Mixed integer programming was also used to get a real optimal solution.

Sustainability reporting is constantly paid attention by companies for its economic, environmental and social benefits. It supports making use of the wide potential for further development of enterprises and society. Individual sectors use types of indicators that correspond to their specifics. It is also the case of the forestry sector, which is especially characterized by a number of non-market outputs. However, we can find also other specific indicators that are relevant to forest management. The paper proposes indicators for sustainability reporting, which are not part of usual methodologies. These indicators will contribute not only to the formal preparation of sustainability reporting, but so that its benefits would be of significant influence on the development of forest enterprises and the forestry sector using its potential in all areas.

Interest in conifer-broadleaf mixedwood forests has greatly increased due to continuous demand for hardwood products and a shift towards more biological or ecosystem-based management. In British Columbia, more than 30% of the productive forest land is a conifer-broadleaf mixture and current forest regulations are more conifer biased rather than maintaining a mixed-species condition. The aim of this study was to examine the impact of paper birch on white spruce growth. Spruce growth data from 10 to 18 years old complex stands indicate that radial, height, and stem volume was not impacted by retaining up to 3,000 stems.ha^-1 of birch. Similarly, growth and yield model projections suggest spruce-birch stands would be more productive up to a threshold birch density (3,000 stems.ha^-1) than pure spruce stands. At a 4% real interest rate, the removal of birch from these stands does not appear to be warranted as an investment. The results suggest that instead of encouraging uniform broadleaf removal across conifer plantations, mixed species management strategies could enhance the forest productivity, stand diversity and resilience.

Different variants of regeneration felling or different light conditions (total site factor 15-95%) and weed control were evaluated in relation to the 4-year development of individuals of regenerated sessile oak. The regeneration density is not dependent on light conditions. The highest mortality occurs on the open area of clear felling. For a certain time in youth, it is possible to consider oak as a shade-tolerating species. With the increasing light intensity the diameter and height growth of oak seedlings increases proportionally, being the highest at 100% light intensity. However, to support at least medium-fast growth, the species requires minimally 50% light intensity (smaller closed clear-felled areas). On the other hand, more extensive unprotected cleared areas appear to be quite unsuitable at the initial stages of regeneration. The positive effect of weed control on the success and growth of natural regeneration is questionable. We recommend developing the regenerated stand by means of a series of small-area (about ≤ 0.3 ha) two-stage felling with a medium-long regeneration period (15-20 years).

Vegetative propagation of forest tree species is of great importance not only for breeding programmes but also for the conservation of valuable populations of tree species. Important is also a possibility of improving the genetic quality of established stands. Beech is a tree species that can substantially increase the stability of forest ecosystems. Minimal information is available about the ontogenesis of rooted cuttings of beech in forest stands for the time being. In our experiments that were gradually established since 1993 we acquired the first significant results of the evaluation of health status, phenological phenomena and growth of these plants. Our findings indicate that it is possible to use rooted cuttings as an element stabilising man-made forest stands including the transferred genetic quality. The evaluation of the 2^nd generation rooted cuttings of beech also provided positive results.

Different transformations of RGB colour space were compared to develop the best method for discrimination of vegetation from the background in open pure cork oak stands in southern Portugal in high-resolution colour imagery. Normalised difference index, i1i2i3 colour space and other indices developed for classic band imagery were recalculated for near infrared imagery and tested. A new method for fully automated thresholding was developed and tested. The newly developed index shows the equal accuracy performance but provides the smallest overestimation error and retains the largest scale of grey levels for a subsequent shape analysis.

Physical, chemical and microbiological properties of soils were studied in black walnut (Juglans nigra L.) stands and compared with those in stands of natural species composition, in mixed stands of black walnut with linden and in pure oak stands. The objectives were to consider a possibility of black walnut planting at floodplain sites in the alluvial area of Southern Moravia. The first results did not show any worsening of soil properties and soil production potential. A positive amelioration effect of soil- improving species was proved in black walnut stands.