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The foliar nutrient status was examined in a degraded Greek fir (Abies cephalonica Loud.) forest in Mount Parnitha near Athens, Greece. The examination lied in comparing the foliar concentrations of Ca, Mg, K, N, P, Fe, Mn, Zn and Cu with the critical values referring to conifers and the elemental percentages with regard to N of the forest with the corresponding percentages of a healthy Bulgarian fir (Abies borisii regis) stand, the closest relative of the Greek fir. It was found that the needles of the Greek fir had significantly lower concentrations from the N and P critical values. Significant differences were found for the Ca/N, Mg/N, P/N, Fe/N and Mn/N percentages. Significant correlations for the Greek fir were found between needle weight and foliar N as well as between needle weight and the percentages Ca/N and Fe/N. It is highly probable that N and P in the Greek fir are in short supply.

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).

The paper presents the results of laboratory tests aimed at the study of storage place, storage manner and storage time in relation to mechanical properties of briquettes made from spruce shavings. A BrikStar 50 briquetting press with a pressure chamber 65 mm in diameter of the Briklis firm was used for the briquette production. All briquettes were made at the constant adjustment of all parameters of the briquetting press. The briquette properties were evaluated by determination of their density and rupture force. Moreover, mechanical durability, gross calorific value, total mois­ture and ash content were determined. It follows from the results of tests that at briquette storage in a well closed plastic bag neither place nor storage time influenced significantly their life time. At briquette storage in a net plastic bag various intensive damage to briquettes occurred, mainly depending on their storage place and storage time.

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.

The felling and skidding damage to residual trees was investigated in a selectively cutting operation in the Caspian forest of Iran. The logging operation was performed by chainsaw and cable skidder. Prelogging, after felling and skidding operations residual tree injuries (species, DBH and damage) were inventoried by systematic plot sampling. Two types of tree damage were observed: destroyed and injured. In this study felling operations mainly injured trees whereas skidding was the main cause of destruction. The percentage of destroyed and injured residual trees by felling operations was 1.4% and 3.4%, whereas the percentage of destroyed and injured residual trees by skid­ding operations was 5.2% and 11.1%. About 87% of destroyed trees were found in the DBH class smaller than 22.5 cm. Maple and Alder were the most damaged trees among the other trees species. Damage to the lower bole and wood damaged intensity were the most common type of injury. To reduce the stand damage, skid trails should be planned before felling and felling directions should be predetermined. In the selection cutting management, limiting logging damage to residual trees must therefore remain a major objective.

The life cycle operation phase of John Deere 1490D energy wood harvester from the aspect of energy audit and environmentally negative influence caused by emissions were evaluated. Energy audit quantifies energy used in the form of fuels and oils as well as energy expended for manufacture, transport and distribution of these fuels and oils. Emissions produced by operation are determined according to the consumption of fuels and oils based on emission factors. We also made a comparison of the general calculation of costs based on data provided by the manufacturer with costs ascertained in real operating conditions. The costs are divided into purchase, operating and other costs. Total costs are subsequently converted into unit costs according to the assumed productivity of the machine, its estimated lifetime, and the mean real throughput of the machine. The machine throughput, and thus also its operating economics, is greatly dependent on the character of the processed material, its stem volume, moisture, way of dendromass preparation, and operator's skills. Energy use was calculated at 74.4 MJ.FU^-1 (functional unit) related to fuel consumption and 13.4 MJ.FU^-1 related to the consumption of oils. The total energy use of the life cycle operation phase of the slash bundler was determined as 87.8 MJ per each bundle produced. The real productivity of the machine in the given operating conditions was several times lower than the productivity indicated by the manufacturer.

Biochar (BC), the carbon-rich by-product resulting from pyrolysis of biomass, is used for bioenergy and increasingly as a soil additive for carbon sequestration and soil improvement. However, information about the effects of BC on forest productivity and reforestation success, especially on boreal and temperate forest soils, is scant. We examined the effects of two BC types (Canadian and Finnish) added in proportions up to 60 vol.% into a common alluvial silty soil on the growth of transplanted Norway spruce (Picea abies [L.] Karst.) seedlings in a growth chamber. We found no marked differences in seedling growth among the binary growing media mixes used. Seedling growth attributes (seedling height, terminal shoot growth, root volume) differed consistently only between the BC types in the highest proportion used. The terminal shoot growth differed overall among the two BC types. These results suggest that BC may be applied into mineral soils without detrimental chemical effects on tree plantation success. Our results provide foundation for further field research on the longer-term impacts of adding BCs to boreal forest soils.

The purpose of this study was to assess the volume increment diversification of selected provenances of grand fir growing under mountain conditions of Poland. The mean increment was determined on the basis of volume reached by the respective provenances when trees were 30 years old while the current increment was calculated from a difference between the volume when trees were 30 years old and the volume when they were 26 years old. It was found that the productive (increment) potential of tested grand fir partial populations is determined by the genotype (provenance). Among the tested provenances grand fir from Salmon River on Vancouver Island in Canada is characterized by the greatest productive capacity.

Studies were undertaken to investigate the composition, structure and diversity of four different types of North Mongolian montane forest near the southern border of the taiga. These forest types, classified as willow-poplar, larch-birch, spruce-fir and Siberian-pine forests, were found to be significantly different with respect to the elevational gradient. In the study area, two fire regimes could be distinguished at lower and drier elevations, frequent surface fires resulted in less diverse forests comprising coniferous species, which in their adult form were found to be fire-resistant, burn-colonizing and light-demanding deciduous tree species. In contrast, the forests colonizing the moist, higher elevations and shaded slopes had a higher diversity of tree species with greater basal area, higher proportion of deadwood, and more regenerating trees; here the coniferous shade trees experienced infrequent but destructive treetop fires. Overall, our results showed that the four forest types differed in composition according to the tree species, diameter and height classes.

A few individuals of Grayish oak have been observed in the Low Murgia Plateau, Puglia Region. This is the first time that Quercus pedunculiflora C. Koch has been found in Italy. The territory is dominated by olive trees, where spontaneous vegetation occurs only in residual patches in particular along an important old dry erosion stream, Lama Lamasinata. Individuals of Grayish oak are located along a rural road and in a closed abandoned park which is in the vicinity of Lama Lamasinata, near Balsignano, one of the most important archaeological sites of the Low Murgia Plateau. In the area other deciduous oaks such as Italian pubescent oak, the most common spontaneous oak in the western district of the Murgia Plateau, and Hungarian oak, which is very rare in the Low Murgia Plateau, have been observed.

This paper describes the forest fire dynamics in the city of Sanming in Fujian province, China, from 2000 to 2009 with a view to understand the number of fires and burned areas in different counties. It also includes the spatial-temporal distribution of fires and application of the Canadian Forest Fire Danger Rating System (CFFDRS). Daily forest fire data was provided by the Department of Wildfire Prevention of Sanming Forestry Bureau. FWI calculator v.7.0.2.76 was used in this study for analysing the weather parameter data. The results showed that a total of 818 fires and burned areas of 8721.16 ha were found during the study period of 10 years. However, the highest and lowest forest fires were found in Youxi county and Sanming district, respectively. Most of the fires with large burned areas occurred at 2 p.m. Moreover, occurrences of fires were found the highest and lowest in March and June, respectively. Based on FWI calculation, the highest danger rating value was found in March, 2009. This study proposes that it would be possible to manage regular forest fire occurrences through the application of CFFDRS. Finally, to plan the fire prevention and management in southern China and other tropical countries, this system has a great opportunity for further implementations.

Fraser fir (Abies fraseri) Christmas tree plantations in North Carolina are infested by root rot caused by Phytophthora cinnamomi. This disease kills almost 100% of Fraser fir material and leaves the soil permanently infested. Control crossings of Mediterranean fir hybrids Abies cilicica × Abies cephalonica with Abies fraseri were performed to ensure possibly resistant hybrid material of desired Christmas tree parameters. Pollen of various clones of A. fraseri was shipped to the Czech Republic by NCSU. Control pollinations were performed in April/May 2010 and 2011 in our hybridization seed orchards. Female strobili were isolated in the period of their highest receptibility. Cones were collected during September. Cones were dried and completely disintegrated. Basic parameters of cones and seeds were assessed for each seed lot. Seed samples of the individual seed lots were X-rayed for assessment of the final share of full seeds. In 2010, the most successful combination CZ2 × NC81 brought 7% of viable seeds. In 2011 the most successful combination was CZ2 × NC26 with 18% of viable seeds.

The present study examines the relationships between the indicators of tree species and structural diversity and the quality of timber production in young even-aged forest stands with the average age below 40 years. The study is based on the forest inventory data from University Forest Enterprise Kostelec nad Černými lesy, Czech Republic, performed from 2009 to 2011. The examined young stands were recorded in 256 sample plots representing 21.2% of the enterprise area. On each sample plot, we quantified 171 partial biodiversity indicators. In total, we analysed 16,416 different variants of the relationship between the diversity indicator and the quality of timber production. The analysis revealed that similarity indicators such as the range of tree heights, Canberra distance, Bray and Curtis index, and index of species evenness and heterogeneity were the most frequent basic indicators occurring in significant correlations. The results indicate a positive relationship between the proportions of assortments in quality classes I to IV and stand diversity expressed by the number of tree species and Canberra distance.

The study described in this paper was undertaken in order to assess the impact of different woody plants on the dynamics of phenolic acids in soil. The influence of plant litter on the amount of phenolic compounds occurring in soils beneath several deciduous and coniferous tree species was examined in pot experiments. The contents of endogenous methanol soluble free and conjugated phenolic acids in Norway spruce, larch, rowan and two species of willow were determined. We focused on the dynamics of water-soluble and reversibly bound phenolic acid contents in the upper layers of soil substrates in pots after the cultivation of studied woody plants.

Changbai Mountain Natural Reserve (1,985 km² and 2,734 m a.s.l.) of Northeast China is a typical ecosystem representing the temperate biosphere. The vegetation is vertically divided into 4 dominant zones: broadleaved Korean pine forest (annual temperature 2.32°C, annual precipitation 703.62 mm), dark coniferous forest (annual temperature -1.78°C, annual precipitation 933.67 mm), Erman's birch forest (annual temperature -2.80°C, annual precipitation 1,002.09 mm) and Alpine tundra (annual temperature -3.82°C, annual precipitation 1,075.53 mm). Studies of soil carbon (C) and nitrogen (N) mineralization have attracted wide attention in the context of global climate change. Based on the data of a 42-day laboratory incubation experiment, this paper investigated the relationship between soil moisture and mineralization of C and N in soils with different vegetation types on the northern slope of the Natural Reserve Zone of Changbai Mountain. The elevation influence on soil C and N mineralization was also discussed. The results indicated that for the given vegetation type of Changbai Mountain the C and N mineralization rate, potential mineralizable C (C0) and potential rate of initial C mineralization (C₀k) all increased as the soil moisture rose. The elevation or vegetation type partially affected the soil C and N mineralization but without a clear pattern. The moisture-elevation interaction significantly affected soil C and NO₃^--N mineralization, but the effect on NH₄⁺-N mineralization was not significant. The complex mechanism of their impact on the soil C and N mineralization of Changbai Mountain remains to be studied further based on data of field measurements in the future.

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 growth, survival, damage and provenance × environment interactions of 30 provenances of Norway spruce (Picea abies L.) from Poland, Slovakia and the Czech Republic, were analyzed at the age of 26 years. Significant effects of altitude and site quality but no geographic trends were dectected in the series of 5 provenance plots. Correlation of growth and survival appeared to be insignificant at individual plots and their series. The highest differentiation among provenances was revealed on the plots at the minimum and maximum altitudes (350 and 950 m). Several Slovak (Western-Carpathian) provenances proved to grow significantly better than the average at nearly all plots, and also exhibited insignificant provenance × site interaction. Indigenous provenances from the southern part of the Western Carpathians showed higher adaptability to sites in lower altitudes with longer vegetation but seasonal water deficiency.

Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkonoše and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkonoše Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkonoše Mts. implies that the macromycete species composition developed quite differently but with a similar success.

The paper deals with the issue of mapping the age composition of stand groups using hyperspectral imagery acquired by the AISA Eagle VNIR sensor in the Bílý Kříž locality in the Moravian-Silesian Beskids Mts. An object-oriented approach was employed through segmentation and subsequent classification by means of Nearest Neighbour (NN) algorithm in the environment of eCognition Developer 8 and artificial neural network (ANN) classification provided by ENVI 4.7 software. Because of the dominant occurrence of Norway spruce (Picea abies [L.] Karst.) monocultures in the studied locality the work focuses primarily on the distinguishability of two selected age classes of Norway spruce (10-20 years and 70-80 years). It studies possibilities of a more detailed age estimation of stand groups aged from 10 to 80 years based on the classification into the boundary classes, which shows similarity to dithering based on random algorithm. Comparison with the outline map of the Forest Management Plan shows a correlation (r² = 0.83) between the spectral characteristics of Norway spruce stands and their age composition.

The paper presents the evaluation of data on precipitation totals and on SO₄^{2 -}concentrations and S-SO₄^{2 -} fluxes in lysimetric waters in a submontane beech stand. The records cover continually a 19-year period. The site is situated in the Kremnické vrchy Mountains, belonging to the West Carpathians Mountains. The material was sampled on two plots. The first had been clear cut immediately before the research started (1989), the second was covered with the original forest stand. In total, the highest SO₄^{2 -} concentrations on the open plot were measured four years after the intervention (1993) at the soil depth of 0.25 m (40.50 mg.l^-1). The lowest values were recorded in 1989 on the control plot at the soil depth of 0.25 m (4.54 mg.l^-1). The sulphate sulphur deposition was the highest in 1995 in the surface humus layer on the open plot (51.8 kg.ha^-1.year^-1). A very significant influence of precipitation totals on sulphur amounts deposited in the particular soil horizons was also confirmed. No interannual differences in SO₄^{2 -} concentration and S-SO₄^{2 -} fluxwere proved.

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.

The aim of this study was to investigate the wood density of Turkish hazel (Corylus colurna L.), an introduced species in the Czech Republic. Sample trees coming from a Czech site were tested for basic wood density and oven-dry density according to Czech national standards. Four sections were taken from each tree to evaluate the variability of wood density along the stem height and along the stem radius. The mean values for the basic density and the oven-dry density were 544 kg.m^-3 and 627 kg.m^-3, respectively. The results show that the highest density can be found in the bottom part of the tree, followed by a decline with the increasing height of the stem. For the radial direction from the pith to the bark, the pattern of density variability was more complex, reaching its highest value close to the cambium. Practically no correlation between annual ring width and density values was found out.

The Bruks mobile chipper was tested for chipping extracted non-merchantable stemwood at the roadside in Pine plantation in Victoria. The elemental time study method was used to evaluate the system productivity. The productivity, cost, biomass yield, remaining slash, chip quality (size classification and energy content), and fuel and energy consumption were analysed. Chipping extracted small logs at the roadside yielded a productivity of 43.88 GMt.PMH₀^-1 (19.4 BDT.PMH₀^-1). The average cost was about 16.96 USD.GMt^-1 (38.36 USD.BDT^-1).

A road network in forest lands provides easy access to forest resources for extraction, regeneration, protection and recreation activities. Erosion from forest roads and skid trails is a major concern in forest management due to the capability to cause adverse environmental effects. The objective of this paper is to introduce two methods for reducing erosion on forest roads and skid trails: water diversion and vegetation cover. Factors affecting erosion on forest roads and skid trails are climate, quality of forest road surfacing material, traffic, slope and vegetation cover. There are several management practices to mitigate the impact of logging and forest road and skid trail construction on stream water quality. Sediments delivered to streams from roads and skid trails lead to a number of dramatic effects on water quality and aquatic life. These management practices were found to be effective in controlling and reducing the runoff volume and soil erosion. Therefore, management and maintenance of forest roads and skid trails are essential elements to mitigate erosion.

This paper presents research results of the performance of HSM-904 grapple skidder using a full tree harvesting method in a non-native aspen Populus deltoides plantation in even terrain conditions in Shafaroud, Northern Iran. Patch cutting as a silvicultural method was used in the plantation (2,000 ha). To evaluate the newly introduced machine to a ground skidding system in the aspen plantation and the possibility to increase the production rate, an empirical time study was conducted. The elements of the skidding work phase were identified and 58 cycles were recorded for the study. The models for effective time consumption, total productivity and work phase models are calculated. The average load per cycle was 2.2 m³, the average one-way skidding distance was 253 m. The average travel speed of unloaded skidder was 5.53 km.h^-1 and the average speed of loaded skidder was lower than the speed of the unloaded one by 2.94 km.h^-1. The average output in the study was 7.1 m³ per effective hour and the unit cost was 13.9 USD.m^-3.

The research was aimed to estimate above- and below-ground carbon stock in Tankawati natural hill forest of Bangladesh. A systematic sampling method was used to identify each sampling point through Global Positioning System (GPS). Loss on ignition and wet oxidation method were used to estimate biomass and soil carbon stock, respectively. Results revealed that the total carbon stock of the forest was 283.80 t.ha^-1 whereas trees produce 110.94 t.ha^-1, undergrowth (shrubs, herbs and grass) 0.50 t.ha^-1, litter fall 4.21 t.ha^-1 and soil 168.15 t.ha^-1 (up to 1m depth). The forest in the study area is a reservoir of carbon, as it has a good capacity to stock carbon from the atmosphere. To realize the forest sector potentiality inBangladesh, the carbon sequestration should be integrated with the Clean Development Mechanism (CDM) carbon trading system of the Kyoto Protocol.

This paper documents the development of soil conditions in the set of 32 permanent research plots in the Krkonoše (Giant) Mts. These plots represent an altitudinal gradient covering the ecosystems of beech, mixed beech-spruce and spruce stands. In all plots, representing the site conditions of the highest areas of the mountain range, standard soil pits were prepared and the soil sampling was performed in autumn of years 1980, 1993, 1998, 2003 and 2009. The results reflect extreme site conditions, soil acidification, large scale surface liming and in minor extent also different tree species composition of the stands. The general type of the soil-genesis is represented by the podzolisation, overlapping the other soil-genetic factors, including the tree species composition. Nevertheless, this development is mostly expressed in the spruce stands. The beech dominance and/or co-dominance are reflected especially by more efficient N-cycling, higher pH, S and V values and fluctuation and lower extractable Al3+ content. More efficient cycling in beech ecosystems is insignificantly documented for plant available phosphorus, calcium and magnesium contents; on the contrary higher dynamics for iron ions was registered in the spruce stands. The long-term soil dynamics with a hysteresis (evident on the base of ordination analysis) can be divided into some periods - processes of acidification (typical in the 1980's samples), liming (main effect in 1993 and 1998) and regeneration (2003, 2009). Other features, important for the soil development, are probably related to the vegetation change, but this relation is not statistically significant.

In an Island of the Netherlands, Pine (Pinus nigra) was planted to stabilize the dunes and to protect the arable lands from the blowing sand. This research was conducted to understand the most important environmental factors responsible for a vegetation change in the Pine plantation and effect of this change on the rare orchid population: Goodyera repens and Listera cordata. Vegetation sampling was carried out according to the Braun-Blanquet phytosociologic method within the three sites of this Island. Twinspan analysis confirmed the definition of three site types and redundancy analysis showed a significant difference between the pure Pine stands and the plots with regeneration. The results revealed that the most significant explanatory variables were litter cover, broadleaved tree cover, and shrub cover indicating the vegetation change under the Pine plantation. The abundance of Goodyera repens is strongly associated with the Pine forest and negatively related to broadleaved cover. Listera cordata could apparently cope with vegetation change. Controlling the herbaceous layer in the Pine plantation can promote the orchid population but on the contrary, promoting the natural regeneration of broadleaved species might endanger them.

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.

The effect of Scots pine admixture in European beech stand on the leaching of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), nitrate nitrogen (NO₃-N) and ammonium nitrogen (NH₄-N) from organic and humic horizons of Dystric Arenosols was studied in northern Poland in 2008-2009. Three zero-tension lysimeters under organic and humic horizons were installed in pure beech and mixed pine-beech stands. Water samples were collected after each rainfall, measured volumetrically, filtered and analysed. In each sample pH and concentrations of DOC, DON, NH₄-N and NO₃-N were analysed. Stronger acidification of leachates was observed in mixed stand compared to pure beech. About twice higher concentration of DOC and its fluxes per unit area were determined in mixed stand. The fluxes of DOC from unit mass of soil were less varied. In general, lower concentrations of DON, NH₄-N and NO₃-N as well as fluxes of the components (calculated in mg.kg^-1DM.year^-1 and mg.m^-2.year^-1) were observed in mixed stand.