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Landslide is one of the negative sides of building non-standard roads in forest areas. The aim of the present study was to assess the effect of biological stabilization on landslide at the edge of forest roads in south and north aspects. For this purpose, in Neka forest (Mazandaran province) three treatments including control, sliding and stabilized areas covered by 35-years-old even-aged alder trees were selected. Benchmarking and soil sampling were conducted during three periods including July, November after rainfall events and March after rainfall events. The results showed that the mean movement of landslide in north direction was 9 cm, while this value was 6 cm in south direction. Sliding in north direction was 32% more than that in south direction. Biological stabilization by alder in north and south direction caused a 33 and 66% reduction in landslide movement, respectively. The characteristics of soil mechanics were different between stabilized and sliding areas. Besides, the soil texture in north direction for control and stabilized areas was clay with high liquid limit (CH) and for sliding area it was clay with low liquid limit, while this value in south direction was CH for three treatments of control, stabilized and sliding areas. To plan biological stabilization, the mechanical characteristics of soil, site features, and appropriate plant species should be considered as important factors.

Experimental results from the first thinning in mixed stands are not broadly experienced by forestry practice. To extend the experience with the thinning of a mixed stand, we studied thinned and unthinned mixtures of Norway spruce with European beech on two study sites in the Czech Republic, which represented different conditions: Všeteč (age of 19-35 years) - originally beech dominated site at 440 m a.s.l. and Deštné (age of 17-33 years) - originally spruce with beech site at 990 m a.s.l. Spruce and beech were mixed individually or in small groups. As the for number of trees, mixtures were 35-54% beech and 46-65% spruce at a lower altitude and 7-30% beech and 70-93% spruce at a higher altitude. In the period 1997-2013, we observed annually: mortality, diameter at breast height of all trees and height of trees (minimum 30 individuals) that represented diameter distribution. Results showed that the growth and development of young mixed spruce/beech stands were positively influenced by the first pre-commercial thinning on both locations. The most pronounced effect of thinning consisted in a decreased amount of basal area of dead trees. On control plots, salvage cut accounted for 34 and 46%, while on thinned plots it reached only 7-8% (thinned from above) and 18% (thinned from below) of basal area periodic increment during the 16-year study period. In contrast, diameter distribution was still relatively wide (i.e. an important amount of thin trees was left) at the end of observations on all plots of both study sites. Thinned stands also showed the better static stability (expressed as an h/d ratio) of dominant spruces compared to unthinned stands on both locations. Additionally, thinning supported the spruce share at a lower altitude and the beech share at a higher altitude.

This study is focused on testing progenies of common and narrow-leaved ash based on the measurement of provenance trial plots established in various forest regions under different site conditions within the Czech Republic in the spring of 1999. Height and diameter growth of 35 provenances was measured and evaluated at the stand age of 10-14 years. The main goal of this research is to analyse and compare differences in growth between progenies originating from alluvial versus scree habitats as well as between the two evaluated ash species. Moreover, the influence of localities on growth was tested using standard provenances planted on all plots. The results of the last measurement were compared with those from the first survey in 2000 at the age of 4-5 years (1 year after planting). With the exception of DBH on the Koněprusy plot, statistically significant differences in height and diameter growth between provenances were verified. The results confirmed a very strong site influence on growth. The main conclusions indicate significant differences in growth parameters between provenances, faster growth of alluvial versus scree provenances on most lowland plots, and generally faster growth of narrow-leaved ash as compared to common ash.

The paper analyses the growth, structure, production and soil chemistry of different tree species stands 20 years after allochthonous spruce dieback. The experiment was carried out at lower altitudes (300 m a.s.l.) at rich sites of the Central Europe region. Norway spruce (Picea abies Linnaeus) and beech (Fagus sylvatica Linnaeus) stands established by artificial regeneration were compared with silver birch (Betula pendula Roth), aspen (Populus tremula Linnaeus) and birch-aspen stands, which were regenerated naturally. Spruce stands showed a decrease of site index (site index 3), compared with the previous generation (site index 2). This leads to an expected lower production at the age of 100 years, compared to mature beech stands, which showed a site index of 1. The highest production (tree overbark volume) was found out in the aspen stand - 294 m³.ha^-1. The production (tree overbark volume) of other monoculture stands was comparable and reached 201-222 m³.ha^-1. Most of the soil chemical characteristics under the compared stands (Ca and Mg content, Al content and active and potential soil reaction) were significantly better under aspen and decreased in the following trend: birch - beech - spruce.

Scots pine covers large areas on sandy soils in lowlands of the Czech Republic. These sites can be threatened by non-sustainable biomass removal after clear-cutting. Totally 14 young pine stands at 14-26 years of age were analysed. Particular biomass components were separated, weighed and analysed to investigate their biomass and nutrient contents such as N, P, K, Ca and Mg. Results showed that leaving slash (needles and branches) plus belowground biomass (stumps and coarse roots) on the site represents 51% of calcium, 62% of magnesium, 74% of nitrogen, 67% of phosphorus and 72% of potassium. The total nutrient pools (without fine roots) were 171-377 kg.ha^-1 for nitrogen, 34-72 kg.ha^-1 for phosphorus, 74-172 kg.ha^-1 for potassium, 82-180 kg.ha^-1 for calcium and 19-42 kg.ha^-1 for magnesium. Needles and live branches are the most important pools of nutrients and the extraction of these parts of biomass can negatively affect the nutrient balance of forest stands on nutrient-poor sites. Stumps with coarse and fine roots also represent a significant pool of nutrients which is left on the studied sites.

Organic nitrogen is an important but yet not very well explored component of nitrogen deposition. In this study concentrations and fluxes of organic and inorganic nitrogen in bulk precipitation in an open field (BOF) and in throughfall (THR) were evaluated at the Bílý Kříž experimental site (Moravian-Silesian Beskydy Mts., Czech Republic, 908 m a.s.l.) with a young Norway spruce stand. The results of a two-year study (2008 and 2009) were compared with the results obtained during the same time period on forest plots included in ICP Forests Programme in the Czech Republic. Total nitrogen deposition in BOF at the Bílý Kříž site amounted to about 918 mg.m^-2.a^-1, the contribution of organic nitrogen was about 8%. Total nitrogen flux with THR at Bílý Kříž was about 1,305 mg.m^-2.a^-1 during the studied years and organic N accounted for 12% of this amount. The ranges of the two-year average values found for total nitrogen flux on ICP Forests plots throughout the Czech Republic were as follows: 759-1,857 mg N.m^-2.a^-1 with 7-38% contribution of organic N in BOF and 928-3,816 mg N.m^-2.a^-1 with 7-20% contribution of organic N in THR. The share of organic nitrogen in THR nitrogen fluxes at Bílý Kříž proved clear seasonality with maxima in July. A highly significant correlation between N-NH₄⁺ and N-NO₃^- concentrations in BOF suggested the common anthropogenic source of these substances at the Bílý Kříž site. No significant correlation was found either between organic N and N-NH₄⁺ or between organic N and N-NO₃^- concentrations in BOF. Cumulative deposition charts showed different behaviour of particular nitrogen deposition components while passing through the canopy.

Time consumption and productivity of a Valmet 890.3 8 wheel forwarder were evaluated on an Australian radiata pine clearfell site with a slope of 21 to 45% (12 to 24°). Cycle time was significantly related to extraction distance. Productivity was significantly related to extraction distance and load volume. Slope did not have a significant effect on cycle time or productivity. Productivity was considerably greater than that for many published studies, which was likely to have been the result of many factors at the study site affecting load sizes and cycle times, including the large load capacity of the studied forwarder, larger mean log volumes, larger log volumes per loading stop, fewer log assortments, potentially larger forwarder grapple volume capacity, log lengths suited to efficient loading and higher travel speeds.

The article describes natural, combined and artificial regeneration on 38 permanent research plots in both Czech and Polish part of the Krkonoše Mts. The attention is paid to species composition, spatial (horizontal and vertical) and age structure of forest regeneration according to different stand and site conditions. Concerning the structure and dynamics of forest stands and their regeneration, the potential and prospects of regeneration according to particular developmental stages and stand types (beech stands; mixed stands: spruce-beech, fir-beech, spruce-fir-beech; spruce stands, stands in the ecotone of the upper forest limit and relict pine woods) were evaluated. In many aspects the plots show several similarities, nevertheless the regeneration in different site and stand conditions show clear differences in dynamics of development. The main differences are result of different ecological conditions, environmental limits and biological characteristics of dominant tree species.

One of the important issues both in the political discussion about climate change and in forest ecosystem research is carbon sequestration. In this paper, we estimated soil carbon sequestration (SCS) in two Persian oak forest stands of different origin (seed and coppice). Soil samples were taken at two soil depths (0-15 and 15-30 cm) and locations (under the tree crown and open area) in each oak stand. Results showed that surface layers (0-15 cm) had the highest soil carbon sequestration ranging from 41.2 t.ha-1 to 47.9 t.ha-1 for both oak forests. The total SCS was higher (between 79.5 and 89.07 t.ha-1) in open areas of the two forest stands than under the crowns of oak trees. Finally, the amount of total SCS in seed originated forest (SOF) (86.52 t.ha-1) was significantly greater (P < 0.05) than in coppice forest (CF) (77.70 t.ha-1). The results indicate that a relatively large proportion of C loss in CF is due to overgrazing, forest degradation and conversion to coppice forests in the study area.

Coppicing was widespread throughout Europe for many centuries but was largely abandoned in the second half of the 19th century. Currently, there has been a renewed interest in coppicing for biomass production and nature conservation. We studied differences in soil chemistry and tree growth between active and abandoned coppices to highlight the impacts of coppice restoration on soil fertility and tree. Stand structure, collected soil samples and tree cores were compared on 46 research plots in temperate Turkey. The plots were set as actively managed and abandoned coppice stand. In our study no effect of coppicing on growth rate was confirmed. Active coppice stands had lower content of Ca, K, N and C:N and higher soil acidification than abandoned coppices. The tree growth rate was significantly higher on more nutrient rich soils. Coppice restoration may not result in increased biomass production in long term periods due to negative effect on soil fertility.

Reduced air pollution load has allowed to use commercially oriented forestry in the Central European mountains since the 1990s. The goal is, however, to restore species- and age-diversified stable stands that are expected to cope with uncertain changes of the harsh mountain climate. The microclimate of current young forest stands can impact on growth and performance of underplanted seedlings. In the present study, aboveground (+10 cm), surface (0 cm) and belowground (-10 cm) temperatures were compared under Norway spruce and Carpathian birch canopies. Measurements were performed in 22-year-old Norway spruce and Carpathian birch stands and replicated three times. These measurements were compared with three adjacent gaps dominated by herbal vegetation. Temperatures were measured automatically during the growing periods 2011 and 2012. The research was conducted on Norway spruce on an acidic Spodosol forest site in the summit part of the Jizerské hory Mts., Czech Republic. Data were analysed using the Horn procedure of pivot measures. The highest variability of aboveground and soil surface temperatures was observed within the gaps during a spring time. The temperatures beneath the leafless birch were close to those within the gaps, whereas in the period of leaved trees the temperature extremes were reduced similarly like under the spruce stand canopy compared to the gaps. The differences between the plots were the smallest at the end of growing seasons.

The paper documents the mid-term changes of the soil characteristics and upper soil dynamics in the stands of introduced tree species, grand fir and Douglas-fir, on the former agricultural lands. These species were compared with Norway spruce stand and original grassland in the same site conditions at the Hrubá Skála locality (Eastern Bohemia). The plot was established in 1980 on Luvisol type of soil, sandy clay. Altitude ranges between 350 and 360 m a.s.l., mean annual temperature was 7.8°C, mean annual precipitation 703 mm. Results confirmed the starting process of the development of humus forms typical for forest ecosystems, despite the initial stage was dominant. The amount of surface humus (holorganic horizons) did not differ between the tree species stands and the agricultural land, but the grassland humus layer contained much more mineral particles. The grand fir was confirmed as a species favourably affecting the site, Douglas-fir affecting it less favourably in the given conditions compared with Norway spruce. Different dynamics was documented for soil reaction, characteristics of soil adsorption complex, soil acidity and nutrient dynamics.

Various forest models that estimate volume, site index, growth and yield, biomass, and sequestrated carbon amounts are based on the information of the tree heights. The tree heights are obtained either directly from measurements or indirectly estimated using height-diameter models. We developed a nonlinear mixed effect height-diameter model applicable to both conifer and broadleaved tree species through the introduction of dummy variable that accounts for the variations in the height-diameter relationship, caused by the effects of species-specific differences. Data from 255 sample plots located within the multi-layered mixed species forests in the central part of the Czech Republic were used. Based on the fit statistics of twelve bi-parametric models, the Näslund's model, which best fits height-diameter data of various species, was selected for expansion by incorporating height of the tallest tree per sample plot, dummy variable, and sample plot-level random effects. As compared to the ordinary least square model, the mixed effect model described significantly a larger part of the variations in the height-diameter relationship and showed a higher prediction accuracy. Large prediction errors still occurred for the mixed species stands when all measured heights other than the focused species (species used in species group-specific model) per sample plot were used to predict random effects and localize the mixed effect model. But those errors were significantly reduced when all measured heights per sample plot, regardless of species were used to predict random effects. We therefore recommend a mixed effect model with random effects predicted using all measured heights per sample plot, regardless of species, to accurately predict the missing height measurements.

A young speckled alder (Alnus incana [L.] Moench) stand was planted on a tract clear-felled due to air pollution and located on a summit plateau of the Jizerské hory Mts. (Central Europe, Czech Republic) at an altitude of 950 m a.s.l. The aim of the experiment was to test the suitability of Alnus incana to form preparatory stands covering the site and thus enabling the reintroduction of more sensitive target species. A potential of Alnus incana to respond to slow-release fertilizing was tested as well. The control treatment showed sufficient growth dynamics, nevertheless, the fertilization significantly promoted the growth (documented by height, height increment and stem-base diameter). If some limitations of alder such as high light requirements are respected, the speckled alder can be recommended as a suitable species for preparatory stands even in the 7^th and 8^th altitudinal (vegetation) zones, especially when fertilized.

Anew approach to forestry that increasingly values non-timber forest functions brings new interest and value also to coppice forests. A case study in the Voskop nature reserve located in the Český kras Protected Landscape Area was focused on a comparison of the timber production of individually growing trees and in multistemmed trees resprouting after cutting (stools). We recorded tree ecological characteristics of trees such as existence of stem cavities, whether the tree grows individually or from a stool and whether or not the tree is broken, dead or has a dying crown. In total 2,670 trees were sampled on a 1,875 ha sample plot. The main tree species forming coppice stands are Quercus petraea and Carpinus betulus. The total stock volume of only 136 m³.ha^-1 is very low at 84 years of age. The stock volume of individually growing trees is 84 m³.ha^-1 and the stock volume of trees in stools is only 52 m³.ha^-1 although the number of individually growing trees is lower.

The Natura 2000 network includes the sites of community importance identified by Directive 92/43/EEC and the special protection areas defined by Directive 79/409/EEC. This network can be considered the cornerstone of the European Union (EU) nature conservation policy in order to ensure the long-term protection of endangered species in their natural habitats. The European Union has adopted an integration approach to the Natura 2000 network. The integration approach is based on combining human activities and nature conservation purposes in Natura 2000 sites and in neighbouring areas. Furthermore, the stakeholders' involvement in the site management is considered a fundamental point for the success of the network. The application of integration approach in Italy was different from one region to another, often presenting a framework where institutional actors collaborate with environmental non-governmental organizations and other groups. These stakeholders influence the Natura 2000 implementation with different strategies, increasing the complexity and unpredictability of the policy outcomes. The objective of this study is to analyse stakeholders' opinions concerning the coexistence of different human activities in the Italian Natura 2000 sites. In order to achieve this objective a semi-structured questionnaire was administered by email to 146 stakeholders. 56 stakeholders filled in the questionnaire and the collected data were statistically processed. The stakeholders assessed the importance of five human activities (nature conservation, environmental education, recreational activities, agricultural activities and forestry activities) in Natura 2000 sites through a pairwise comparison and identified the main opportunities and obstacles of the network. The results show that the most relevant activities are nature conservation and environmental education according to stakeholders' opinions. In addition, the respondents highlighted that the main opportunities are the possibility of access to EU funding and the enhancement of local green economy, while the main obstacle is the restriction of agricultural and forestry practices not adequately compensated.

Physical properties of soil can be affected by machines that are used for skidding which have the potential to impact soil sustainability and forest productivity. The present study evaluated the effect of timber skidding by a rubber-tired skidder and farm tractor on the soil physical properties. The study site was located in Hafdaghanan plantation region in the north of Iran. Two treatments that consisted of skidding by HSM 904 skidder and ITM285 farm tractor equipped with trailer were applied. The trails were included in three traffic levels: primary, secondary and tertiary. Treatment effects were tested using analysis of variance (ANOVA) with skidding machine types and traffic levels. Results indicated that machine type and traffic intensity are the effective factors on soil physical properties. The results showed that with an increase of traffic frequency, bulk density increased but total porosity and soil water content decreased. The results of the study provide clear evidence that farm tractor is a more environmentally friendly machine than rubber-tired skidder in the plantation area.

Horizontal structure of forest stands largely affects the competitive relationships between tree individuals and plays a significant role in the stand dynamics. The present study describes horizontal structure on nine permanent research plots (0.24-0.25 ha) in the regeneration and tree layer of autochthonous European beech (Fagus sylvatica Linnaeus) stands in the wide altitudinal gradient in protected areas in the Czech Republic and Poland. The spatial structure was classified in productive herb-rich beech sites, through acidophilic beech sites, exposed sites, to beech fragments near the timberline. The spatial pattern of tree layer was regular in the lowest parts of the altitudinal gradient of beech, random in the middle parts and aggregated in the beech forests under the hilltop phenomenon and extreme edaphic site. Nevertheless, trees in lower tree layers showed a tendency to the aggregated pattern, similarly like the strong aggregation of natural regeneration. In most cases, the parent stand had a significant negative effect on natural regeneration at a smaller distance (to 0.8-4.2 m). The spatial pattern of dead wood was mostly random. Because of the great plasticity of beech crowns, crown centroids were more regularly distributed than tree stems. The average displacement of crown centroids from the stem base was 1.5 m with the prevailing direction of 52.7% down the slope. Projected canopy cover was on average 10.7% higher compared to the canopy simulated by circular crowns.

Mid-rotation responses to fertilization of Pinus radiata D. Don plantations after the first or second thinning have been observed in research experiments in many regions where the species is grown. The practice is not however common in commercial plantations. This is probably because the effects of soil-site conditions on the magnitude and duration of tree and stand growth responses are not well understood. The effects of nitrogen (150 and 300 kg N.ha-1) and phosphorus (0, 20 and 40 kg P.ha-1) including common base fertilization of boron (8 kg B.ha-1) and potassium (65 kg K.ha-1) were evaluated in three mid-rotation P. radiata plantations after thinning. The plantations were located on sites with contrasting nutrient and water availability, sandy, granitic and red-clay sites, in south-central Chile. The magnitude and duration of growth response was site specific. After 8 years, the growth response to the highest dose of fertilization relative to the control was 57 m3.ha-1 (16%) at the granitic and 24 m3.ha-1 (14%) at the sandy site. No response to either nitrogen or phosphorus fertilizer was observed at the red-clay site. Nitrogen and phosphorus were limiting at both granitic and sandy sites, and high fertilization doses considering 300 kg N.ha-1 plus 40 kg P.ha-1 would ameliorate nutrient resource limitations and yield a cost-effective increment in stand volume.

The study analyses the chemical properties of the soil in open-canopy beech stands in relation to the predominant species of ground vegetation. A hypothesis is examined whether the predominant ground vegetation species can represent in chemical terms different site conditions. Four localities were used for testing reed grass, myrtle blueberry, wavy hair grass and vegetation-free patches. Samples were taken from three organic horizons (litter (OL), fragmented (OF) and humus (OH)) and from the humic first mineral horizon. Significant differences between the variants were found only in the OL horizon, in which the vegetation species explained 65% of the variability in data. The OL horizon in the vegetation-free variant showed the significantly lowest pH/KCl and the lowest potassium content. The most distinct particular differences were observed between the blueberry variant and the grass variants. Although the studied variants of vegetation growing under the beech stand represented significant differences in the litter horizon chemistry, the effects on the other humus horizons and on the upper mineral horizon were marginal.

The reflection of soil properties in the health condition of forest stands is connected with synergy of stressors that influence the forest existence. In the Krušné hory Mts. (Czech Republic, Europe) methods of full-area site mechanized preparation before reforestation were applied on existing ecotopes of the air polluted clear-cut area and the uniform relief of windrows was established. The hypothesis whether the soil in the windrows could be directly used for local cultivations as a substrate suitable for forest tree species growth was examined. The influence of three machines (digger, bulldozer and cultivator) used for the windrow cultivation was monitored in relation to soil properties. The state of the properties of prepared sites was compared with retained windrows and control plots with scarification. The effects of mechanized soil preparation before reforestation were different according to the concrete ecological factors of the given sites. The influences of individual means of mechanization on concrete soil properties were determined as locally differentiated. The windrow cultivation led to an increase in cation exchange capacity (CEC) especially due to an increase in Ca²⁺ and Mg²⁺ content. Locally it led to the stabilization of N-NH₄ content. The optimization of soil physical properties was connected with the state of C_ox. The mechanized windrow cultivation did not optimize either C/N ratio or maximum capillary capacity (Θ_MCC) or porosity (p). The mechanized windrow cultivation in the conditions of decreased air pollution load generally appears as a good technology for revitalization of degraded sites because it provided more optimal trophic conditions for the forest tree species growth than windrows or sites with completed scarification.

This project used the recorded machine utilisation of two machines (harvester and forwarder) by MultiDATs in pine plantations of Southern Tasmania (Australia) to verify the impact of site conditions on utilisation rates over a long study period. The parameters of site conditions included type of forest operations, stand age, site productivity, ground slope and forwarding distance. The correlation ratio between each parameter and machine utilisation was low and not significant at a significance level of 0.05. Harvester's utilisation rate varied from 48.6% to 100.3% while it averaged at 77.3%. Forwarder's utilisation in this case varied from 47.8% to 96.5%. The average rate for forwarder in this study was 81.1%. The long-term machine utilisation rates can be applied by the operation management to control the current level of machine utilisation and to calculate the machine hourly cost accurately to obtain unit harvesting costs.

Soil properties can be affected by heavy equipment used for skidding but these impacts vary greatly with site conditions and operational practices. We assessed the effects of ground-based skidding on site disturbance and soil physical properties. We also tested the effects of skid trail slope and traffic frequency on soil compaction, total porosity, and moisture content. On average, about 30% of all harvested area was disturbed to varying levels. Intact forest floor (undisturbed) and light slash were the dominant surface conditions, covering an average of 68.9% of harvested area. Deep disturbed soils accounted for only just over 1.1% of observations. Results showed that dry bulk density, total porosity and moisture content were affected considerably on skid trails by traffic frequency and skid trail slope. Measurements of soil properties in the surface layer (0-10 cm) showed that bulk density is 57% higher and total porosity is 31% lower on the skid trail compared to the undisturbed area. Average moisture content has been measured as 35% on the skid trail versus 47% in the undisturbed area.

We developed optimal models for predicting the aboveground biomass of European beech (Fagus sylvatica L.) applicable to the national forest inventory data of the Czech Republic. The models were based on a data set of 81 beech trees collected in 19 stands that represent a wide range of stand and site conditions. The relationship between biomass and tree dimensions (diameter D, height H) was modelled using non-linear regression equations with one (D) or two (D, H) independent variables and two or three parameters (D2, DH2, DH3 models). Subsequently additional predictor variables, i.e. tree age, site index and altitude, were added to the basic models. The inclusion of tree age (T) and altitude (A) in the basic DH2 model resulted in the best model for aboveground biomass (DH2AT model). The altitude (A) and site index (S) were important predictors for stem biomass estimate (DH3AS model). Similarly, branch biomass was predicted in the best way by four-variable model DH2AS.

The individual tree growth models are important decision-making tools in forestry. Age dependent and age independent individual tree basal area growth models were developed for Chir pine (Pinus roxberghii Sarg.) in one of the western districts, Rukum district, in Nepal. Data from thirty-five destructively sampled trees, which were representative of all possible stand densities, site productivities, age classes, and size classes of Chir pine forests in the district, were used. Sample trees were felled and diameters and ages were measured on the cut surface of the stump (at 30 cm above the ground). Since measurements from the same stump of a tree were strongly correlated, the autoregressive error structure modelling approach was applied while specifying the model in order to reduce bias. All parameter estimates of the models were significant (P < 0. 01) and the models described most of the variations of basal area growth (R²_adj > 0.86). Residual graphs showed no serious systematic bias for all observed age classes and diameter classes. The age independent growth model showed relatively better fit statistics (R²_adj = 0.8751, RMSE = 4.8494) than its age dependent counterpart (R²_adj = 0.8668, RMSE = 5.0158). Because of being more precise and simpler, the age independent model is recommended to apply to both even-aged and uneven-aged stands of Chir pine in the district.

Two forested catchments in the Bohemian Forest (Šumava Mts.) were investigated according to the species composition of herb layer and aboveground plant biomass. The bark-beetle gradation was observed in the Plešné Lake catchment during this study. The community dynamics depends mainly on the altitudinal zone of the site. Variability in the species composition was more pronounced in the sites of natural broadleaved mixed forests than in the sites of natural Norway spruce forests. Three processes were recorded after the tree layer damage: tree regeneration (very rapid), appearance of some species typical of the clear-cuts (only limited, mainly after windthrows) and disappearance of some species (limited, probably for a short time only). The aboveground biomass was variable. Some relations to the canopy decline were observed for Vaccinium myrtillus. The stock changes depend on the population features of this species and can differ (increase or decrease) according to individual localities.

The results of a fifteen-year period of investigations conducted on Norway spruce in the upper plateau of the Jizerské hory Mts. were summarised. The objectives were to evaluate the growth performance of an experimental plantation under harsh environmental conditions and assess the effects of amendments as well as the influence of the forest site variability on growth performance and survival of young spruces. The following treatments were distinguished: (1) lower control, (2) limestone and (3) amphibolite treatments on a less exposed slope of the ridge and (4) upper control on a summit of the mountain ridge. Principle characteristics such as mortality rate, height, annual height increment, stem base diameter, crown diameter and nutritional status were summarized and evaluated. Significant differences between treatments were recorded in heights. The trees fertilized with amphibolite were significantly taller than the control ones in thirteen out of the fifteen evaluated years and the applied limestone improved heights in ten years out of the fifteen evaluated years. A positive effect of amphibolite treatment on stem base diameter was proved in three of the four assessed years and was persisting till 2007 (last measurement of this characteristic), the positive effect of limestone was lasting up to 2006. The considerable role of the site variability was apparent from a comparison between the upper and lower control although they were in a very close position to each other, growth increment of the spruces on the ridge was significantly lower. Temporarily lower N concentration was recorded in the fertilized treatments in comparison with their respective control. The concentration of P was low and decreased to the limit of deficiency in all treatments, P seems to be the most limiting macroelement in the area.

Clonal propagation is widely used for Acacia breeding and commercial planting. When a large number of clones are handled, problems with mixings are commonly confronted. Detection of admixture in Acacia clones based on morphology particularly at seedling stage is not feasible. However, molecular markers are commonly used to test the genetic fidelity of planting materials. This paper reports the detection of mislabelling in Acacia clonal progenies using a sequence tagged microsatellite (STMS) genetic marker system. Progenies from two mapping populations were clonally propagated and field planted for phenotypic and genotypic evaluation at three locations in Malaysia: (a) Forest Research Institute Malaysia field station at Segamat, Johor, (b) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak and (c) Asiaprima RCF field trial site at Lancang, Pahang. During field planting mislabelling was reported at Segamat, Johor and similar was suspected for Bintulu, Sarawak. Screening revealed mislabelling events in both populations. A total of 18.52% mislabelling incidences were detected from both sites, of which 17.39% of mislabelling was detected for fibre length cross and 20% for wood density cross. The assignment test efficiently reestablished the mislabelled ramets to the respective clones. Future studies should be focused on the utilization of a higher number of markers, e.g. SSR or SNPs to increase a discrimination power. A high number of SNPs can be generated within a short period of time compared to SSR, but SNPs could be cost inhibitory. Multiplexing microsatellite combinations along with sample bulking will further reduce the processing time when screening large populations. The use of assignment test would efficiently assign mislabelled individuals to the respective clones. It is concluded that checking for mislabelling is imperative for future breeding and for analyses such as QTL mapping where a correlation between genotypic and phenotypic data is determined.

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.