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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.

The paper deals with the possibilities of homogenization of the kerf width by proper choice of the respective feed rate and abrasive mass flow for particular models of cutting. The introductory part is devoted to reasons for the kerf width variability in dependence on the models of cutting, as well as to the methods of determining the kerf width in cutting of solid wood by abrasive water jet. In the conclusion are presented the results concerning the development of kerf width in the range of commonly used feed rates and abrasive mass flows.

The paper presents a method for the derivation of total timber production and of increments in value units, particularly in net financial yield for spruce stands damaged by crown defoliation after their dieback. The value production was derived by means of value growth models of undamaged stands and models for the adjustment of volume and qualitative production of damaged and died stands. Changes in timber quality after tree drying and changes in the production of damaged stands compared with undamaged ones are illustrated in tables and graphs. The changes are expressed by means of the indexes of total mean increment and total current increment. They depend mainly on the degree of stand damage expressed by crown defoliation, age and yield class of stand, the age of stand when the damage started and duration of damage. The value of damaged stands after their dieback is lover minimally by 50% than before their dieback. It is caused mainly by deteriorated quality of timber from dead trees in stand.

In order to determine the environment carrying capacity in terms of biomass production utilizable by game 360 representative sample plots (1 × 1 m) were laid out in the growing season on the basis of typological classification in forest stand of an area of 1,796.49 ha in the studied region of the Soutok Game Preserve, Židlochovice Forest Enterprise, Lanžhot Forest District. On meadows, pastures and others areas producing grass and herbs of a total area of 532.87 ha, other 57 sample plots were laid out and sample of biomass utilizable by game. Quantification of the biomass was carried out on the basis of the area cover of grass and woody undergrowth. In total, forest and non-forest land provides 14,659,851 kg grass and herb utilizable biomass. In forest stands production was found of 6,826,662 kg grass and herb biomass (on average 380 g/m²) and on meadows and pastures 7,833,189 kg (on average 1,470 g/m²). Moreover, production of 1,401,262 kg (on average 78 g/m²). Laboratory analyses were carried out of naturally dried-up samples of biomass and these values available energy were ascertained: the energy of grass and herb biomass amounted to 5.7 MJ/kg, the utilizable energy of wooody origin amounted to 4.03 MJ/kg. In view of the standardized game population size up the available food supply sufficient, because the energy requirement was fully covered by their daily quantitative consumption of biomass.

The paper is a contribution to the research on problems of thinnings in mixed (spruce-fir-beech) stands situated in the 5^th forest altitudinal zone (beech with fir) in the central part of Slovakia. The research was carried out on two series of permanent research plots established in 1972. Each of the series consists of three partial plots where one plot was tended by free crown thinning in the framework of whole-area tending. On the second plot a non-whole-area tending was realised while the third ones were left without planned silvicultural treatment as controls. Dynamic changes in tree species composition, stand structure, qualitative and quantitative production including silvicultural analysis of seven thinning interventions were evaluated for a period of 29 years. A special attention was paid to development of future crop trees which are the main bearers of stand quality and quantity. The changes were compared with respect to differences between the plots with whole-area and non-whole-area long-term silvicultural treatment and the control plot (without treatments).

Soil properties of forest ecosystems depend on synergy of both parent material and organisms living in the soil, i.e. tree species communities including related plant and animal species. However these soils were not left intact being converted into agricultural land; addition of both nutrients and organic matter and cultivation using tillage led to increased fertility of topsoil. Even long-term afforested soils show differences which are considered as legacy of past agriculture. The change remains detectable for decades; though the altered properties are obvious especially couple of years after planting (approximately 10 years). We found increased concentrations of nutrients (P, K, Ca, and Mg) and subsequent increased base saturation (V %) in former tilled soil only. Moreover, there were no differences between topsoil and subsoil properties (69% and 72%, respectively). In addition to significantly lower saturation (both 0-10 cm and 11-30 cm layers) detected in the long-term-forest and 50-year-afforested (both covered with Norway spruce stands) soils in comparison with adjacent 10-year-old afforestations, there was found significantly lower base saturation in topsoil horizons compared to underlying ones.

The study deals with the monitoring of dissolved organic carbon (DOC) concentrations in seepage water sampled from differently managed forest plots in the Drahanská vrchovina Upland. Simultaneously, the input of DOC in precipitation and throughfall is evaluated. Preliminary results show higher mobility level of carbon substances in forest soil in a pure spruce stand compared to mixed stand or a pure beech stand. DOC can be one of suitable characteristics to evaluate the conversion effectiveness of spruce monocultures.

The fine root biomass represents 3,372 kg/ha in the intermediate stage of the beech virgin forest with different admixture of goat willow, where the vast majority of this biomass is located in the uppermost mineral soil layer 0-10 cm. The variability of the fine root biomass calculated from 35 sample points represents approximately 90% of the mean value and reaches the highest value within the humus layer. The total fine root length investigated in 10 cm thick soil layers decreases with increasing soil depth. A significant linear relationship between the fine root length (calculated per 1 cm thick soil layer and 1 m² of stand area) and the soil depth was confirmed, although the correlation is rather weak. The number of root tips decreases with increasing soil depth faster than the root length. As the number of tips per 1 cm of root length remains in the finest diameter class without significant changes, the reason is above all a decreased proportion of the finest root class (diameter up to 0.5 mm) from the total fine root length within the particular soil layer.

In recent years, the Czech part of the Silesian Beskids has been affected by strong yellowing of Norway spruce stands and gradual decline of individual trees. Similar damage has also been observed in the neighbouring parts of Poland and Slovakia. The article presents the results of an investigation in the Forest District Jablunkov - part Nýdek. To evaluate the situation, monitoring plots were established and a regional survey was carried out together with tree-ring analysis. The results show a mosaic distribution of damage in the region studied, independent of the altitude and forest type. Defoliation was lower in 20-40 years old stands. Even these young classes, however, show yellowing symptoms. The decline of stands started to be visible at the end of the 1990s; significant loss of vitality was observed in the most affected stands in 2003, after an extremely hot and dry vegetation period. Actual development of meteorological conditions plays an important role in the stand damage. Lastly, possible causes of damage and further development are discussed.

This material describes parameterization of allometric functions applicable to biomass estimation of European beech trees. It is based on field data from destructive measurements of 20 full-grown trees with diameter at breast height (dbh) from 5.7 to 62.1 cm. The parameterization was performed for total tree aboveground biomass (AB; besides stump), stem and branch biomass, respectively. The allometric functions contained two or three parameters and used dbh either as a single independent variable or in combination with tree height (H). These functions explained 97 to 99% of the variability in the measured AB. The most successful equation was that using both dbh and H as independent variables in combination with three fitted parameters. H, as the second independent variable, had rather a small effect on improving the estimation: in the case of AB, H as independent variable improved prediction accuracy by 1-2% whereas in the case of branch biomass by about 5%. The parameterized biomass equations are applicable to tree specimens of European beech grown in typically managed forests.

This study was carried out in a steep and difficult terrain. Trees were logged downhill to the landing by a wheeled skidder Timberjack 450C. Selection cutting was performed on a 66-hectare tract with an average slope of 30%. The elemental time study method was applied to develop the skidding time predicting model. In this study 43 working cycles were included. The skidding cycle time was mainly affected by skidding distance, winching distance and interaction between skidding distance and slope. The gross and net production rate was 20.51 and 22.93 m³/h, respectively. The unit cost considering the gross and net production rate was 6.31 and 6.22 USD/m³, respectively.

Clearcuts are one of the results of forest management. The aim of this study was to assess the effect of clearcuts on bird communities in a managed forest in Western Poland. I applied the method of point transect counts. 20 points were located near clearcuts (less than 100 m from the nearest clearcut) and 25 points in the forest interior. In total, 36 bird species were recorded. On average, I found 9.20 bird species at points located near clearcuts and 6.72 species at points situated in the forest interior, and the difference was significant. The cumulative number of bird species for a given number of sampling points in the vicinity of clearcuts was higher than in the forest interior. The obtained results indicate that in managed, even-aged forests the generation of clearcuts can lead to an increase in local bird species richness.

Following measurements of dead wood (20 to 40 years) at various developmental stages of the life cycle of selected virgin forests of the 1^st to 7^th altitudinal zone the relation of its course was derived. The dynamics and course of dead wood in the life cycle of virgin forests were best represented by a polynomial of the third degree. An analysis confirmed that virgin forests consisting of stable tree species with approximately the same physical age (Boky) showed small differences between maximal increase and decrease in necromass during the whole development cycle. Virgin forests at sites rich in nutrients consisting of several tree species with various physical age had high values of necromass during their whole development cycle. Spruce stands at the upper forest boundary also had a relatively high ratio of necromass at the advanced optimum stage.

Estimation of stand growth is crucial for forest planning. Estimations were usually done using fixed values, and recently growth equations have been used. An alternative is through stand growth models. The objective was to develop a simple model for Nothofagus pumilio stands with full density along site quality and age gradients. The sample was obtained from 125 stands. Data on forest structure and samples for tree-ring measurement were taken in all trees to estimate growths using biometric models previously developed. The growth values of each plot during the last twenty years were calculated to fit the model, using the ratio of total volume increment/basal area as an independent variable. The developed model gives a ratio between stand volume increment and basal area (m/year) in relation to the site quality and stand age. The statistics (r² = 0.819, mean error = 0.019, absolute mean error = 0.033), residual analysis and biological performance were satisfactory. The obtained stand growths varied between 1 and 20 m³/ha/year. This simple model allowed to estimate growth values at a stand level from easy field measurements from forest inventories.

The paper evaluates the development of the tree numbers, secondary stand and species composition on eight partial control plots in Klepačov where the conversion of even aged forest managed under the system involving coupes to selection forest has been implemented within the framework of a long-term project. The plots capture various stages of conversion. Plots A, D, and H still possess structures nearing the forest of age classes. The assessment was made of the measurements taken in 1974, 1994, and 2004. Tree numbers on the partial control plots in the diameter degrees 10-70+ decreased in the first inventory period as compared with both the model situation and the initial situation in 1974 due to increased felling volumes in that period. The felling and the subsequent opening of stands resulted in a rapidly developing regeneration, which manifested itself by the increase in the number of trees in diameter degrees 2 and 6 above the values given by the model curve for these diameter degrees. In the second inventory period, tree numbers in these diameter degrees were lower by 11% as compared with the model situation and slightly lower as compared with the initial situation. Moreover, the results of the survey show that the forest stands under the selection system of management are massively invaded by broadleaved species, namely the beech and that danger exists that broadleaves will dominate in the future. This is generally considered undesirable because the quality of broadleaved stems in the stands under the selection system is low.

The collection and sale of asparagus (Asparagus racemosus Willd.) is a major source of income for Praja and Tamang castes around the Royal Chitwan National Park (RCNP) in Nepal. However, the forests where asparagus is harvested are becoming depleted threatening the livelihood of collectors. To address this issue, at sustainable harvesting practices, the research reported here applied the contingent valuation method (bidding game) and estimated the average willingness to pay (WTP) of collectors to two asparagus collection scenarios. In the first scenario, if forests under the Department of Forests jurisdiction were managed for sustainable harvesting at 1995 rates, the average WTP of collectors was 4.4 NR/kg. In the second scenario, if the forest in the RCNP is managed in such a way that both the current harvesting rate of asparagus is sustained and they are legally allowed to collect asparagus at the present rate, the average WTP of collectors was 8.35 NR/kg. Consequently, there is a good chance of earning revenue for the government and sustaining the livelihood of asparagus dependents by the sustainable management of the Department's and the National Park's forests and giving legal permissions to collect asparagus from the National Park, which would have happened anyway but with financial and legal risks to collectors.

A survey of forest nutrition was carried out in Natural Forest Region (NFR) No. 40 Moravskoslezské Beskydy. The reason for this survey was the gradually worsening state of forest stands in this region and especially in a part of it - in the Jablunkov Pass. Air pollution was the suspected cause of the unfavourable development. According to methodology established for the survey of forest nutrition, the samples of soil and assimilatory organs were collected at 375 sampling sites. The spatial distinctness of Jablunkov Pass was expressed on the basis of selected soil characteristics (quantity of organic material, exchangeable pH, content of total nitrogen, zinc, lead, chromium, cadmium) and of the contents of chemical elements (total nitrogen, magnesium, zinc, lead, chromium, cadmium) in two-years-old Norway spruce needles. These analyses were done by the software Statistica. The medians of concentrations of elements in two-years-old Norway spruce needles in the area of NFR except Jablunkov Pass are: Zn - 34, Pb - 0.71, Cd - 0.15 and Cr - 0.38 (mg/kg). In the area of Jablunkov Pass: Zn - 43, Pb - 12.1, Cd - 0.25 and Cr - 0.41 (mg/kg). Particular attention was paid to the content of heavy metals both in the whole area of NFR and in the area of Jablunkov Pass particularly. The spatial homogeneity is disturbed by the influence of air pollution there. Markedly higher contents of zinc, lead and cadmium are found in the whole soil profile, in the case of chromium in the forest floor only. The distribution of heavy metal contents in the soil profile is influenced by the quantity and quality of organic matter and by the altitude of sampling sites. The higher values of medians of zinc, lead and cadmium contents are found in the area of the Pass. Chromium is an exception with the highest contents found in the southern part of NFR. The medians of concentrations of elements in the forest floor of Norway spruce stands in the area of NFR except Jablunkov Pass are: Zn - 70.6, Pb - 88.6, Cd - 6.4 and Cr - 0.69 (mg/kg). In the area of Jablunkov Pass: Zn - 103, Pb - 138, Cd - 8.8 and Cr - 1.02 (mg/kg). The spatial distinctness of the area around the Jablunkov Pass is confirmed by the evaluation of the data of forest nutrition survey. Particularly, it consists in the high contents of phytotoxic heavy metals. The exceptionally high pollution of this area can be a cause of the physiological weakness of trees with following attack of the honey fungus.

The Bohemian-Moravian Upland shows a large-scale decline and dieback of Norway spruce up to the forest altitudinal vegetation zone (FAVZ) 5. This phenomenon has been observed in the last 7 years and its progress is rapid. Healthy, declining and standing dry trees of equal height were mutually compared in nine forest stands (aged 3-73 years). These parameters were measured: increment dynamics, root system architecture, biomass, fine root vitality and mycorrhiza, infestation by biotic and abiotic agents. Analyses were done for 414 trees, soil characteristics and weather course data covered the period 1961-2004. Warming and precipitation deficit are the predisposition factors. Weakened trees are aggressively infested by the honey fungus (Armillaria mellea), and they die from root rots. In this paper we describe the mechanism of damage to and dieback of the spruce trees concerned.

Dioszeghyana schmidtii (Diószeghy 1935), is forest species protected by European Union. Its distribution has been studied essentially by the use of light traps. However, its biology and habitat preferences are not sufficiently known and thus its habitats may be damaged by forest management. We suggest the beating method in order to collect larvae as an useful way to record and to survey D. schmidtii. Larvae of the species can be collected by beating branches of its host plants (Quercus and Acer species) in the lower canopy (below 3 m). Optimal survey time would be the second half of May and the first half of June. Differences between the larvae of D. schmidtii and 16 similar moth larvae, as well as, Tenthredinidae (Hymenoptera) species living at the same time on the same trees are described and figured in a key to identification. The method described in the paper allows one to identify larvae in the field. Results are discussed.

The incidence of the summer (late-seasonal) growth of shoots was monitored following the planting of Scots pine from different provenances of the Czech Republic and different planting regimes in an experimental plot in Týniště nad Orlicí. In the third year after reforestation the local populations had the highest proportion of summer growth of the shoots (18%) compared to other populations. From the second to the fourth year after planting the percentage proportion of summer shoots was determined for the species Scots pine in conditions of the Polabí region, it was 13.5% of the individuals in each year. The analysis of stem sections demonstrated double rings as a result of the cambium activation through the growth of summer shoots.

In 1986 (1987) research plots were established in a forest stands on the south-western slope of Šerlich Mt., Orlické hory Mts. (Kristina Colloredo-Mansfeld - Forest Administration Opočno), at the altitude of 950 to 970 m, to study deposition, chemistry of precipitation and soil water and development of soil chemistry. The plots were established on a clear-cut area, in a young stand and a mature stand of spruce, in a mature beech stand, and in an advanced growth of spruce and European mountain ash. The content of solutes in creek water was studied at the same time. Since 1993 the concentration of substances in precipitation water intercepted in the summit part of Šerlich Mt. has been measured. Research on water chemistry in the stands terminated in 1997. Soil analyses were done in 1986 (1987), 1993 and 1999. The load of acid air pollutants in these forest ecosystems was high in the eighties. After 1991 the deposition of H⁺, S/SO₄^2-, N/NO₃^- + NH₄⁺, Mn, Zn, Al decreased. Similarly, an increase in pH was observed in soil water, and the concentrations of SO₄^2-, and N, Al compounds decreased. But in 1993 the concentrations of SO₄^2- and Al increased again under the spruce stand for several months. The concentrations of NO₃^-, Mn, Zn and Al in the stream water also gradually decreased in the nineties. On the contrary, the average values of S-ions increased compared to those of 1987 to 1991. Strongly acid soil reaction developed in deeper layers until 1993. In the second half of the nineties the pH/H₂O value somewhat increased again, however the reserve of K, Mg, Ca available cations in the mineral soil constantly decreased. The saturation of sorption complex by basic cations in the lower layer of rhizosphere did not reach even 10% in 1999. The forest ecosystems of Šerlich Mt. were also loaded by a high fall-out of Pb, and increased fall-out of Cu. The lack of balance of N-compound transformations and consumption in the soil and increased leaching of N in the form of nitrates contribute to soil acidification on the investigated plots.

The agro-forestry system is one of the best known indigenous practices for livelihood. In view of instant decline in the rainfed hill agro-forestry system the present study was undertaken in the hilly villages of Uttarakhand state of India with the major objective to assess the status and effects of various factors on this centuries old indigenous agro-forestry system. The survey documented a total of 26 herbaceous food crop species and 21 woody species that were raised by farmers in the selected villages of Uttarakhand. A total of 37 plant species available in the agro-forestry system and used for curing various ailments by traditional healers were also documented during the survey. The major cereals produced by farmers were Oryza sativa L., Echinochloa frumentoacea Link., Eleusine coracana (L.) Gaertner and Triticum aestivum L. The indigenous system of cropping was locally called as Baranaja that revolved around the production of > 12 varieties of crops. Besides food, the species grown in the agro-forestry system were used for multiple purposes. Water scarcity, migration of youth in search of employment and changing socio-economic and climatic conditions were some of the major reasons for declining agro-forestry system and abandoning the agricultural land.

Important parts of the forest sector are forest engineering constructions and capital construction of forest road network which improve the optimal management of forests and forest stands and their reasonable opening by a forest road network. The basic frameworks of forest road network are forest transport roads of various grades and categories. The paper discusses the basic parameters of forest transport roads such as the length of forest transport roads and their density outspread to the area of a particular district above all. The conditions of forest opening in 41 Natural Forest Regions of the Czech Republic and in the Czech Republic as a whole are shown and confronted on the basis of these parameters. A dilemma of the double division of forest transport roads according to the standard ČSN 73 6108 - Lesní dopravní síť (Forest Transportation Network) and according to the methodology used by Forest Management Institute in Brandýs nad Labem is also described in the paper. Although it is not suitable to use two methods of evaluation, there is no tendency to unify it.

The paper deals with the occurrence, development and natural enemies of the cecidogenous aphid Pemphigus gairi Stroyan (Pemphigidae). The aphid abundantly occurred on leaves of Populus nigra and P. nigra var. italica in Brno in 2003. It was described from England and no information on its occurrence is available in literature from continental Europe. It refers to a holocyclic and heteroecious species. In localities under study, larvae of fundatrices hatched mainly in the last decade of April. Through their sucking on the abaxial face of freshly unfolded leaves of poplars, species-unspecific lengthwise tile-like galls originate on the adaxial face of leaves (near the central leaf vein). During 12 to 14 days, fundatrices mature in galls of an average length and width 11.2 and 3.9 mm, respectively. Adults live about 1.5 months, namely max. until mid-July. They produce on average 75.6 fundatrigeniae which mature to winged migrantes alatae in the course of 16 days. In the period of hatching the first migrants (at the end of May), galls grow up to the final length of about 11.8 mm and width 4.7 mm. In primary slit-shaped caps on the abaxial face of leaves, migrants leave the galls through emergence holes. In a secondary host (Aethusa cynapium, Daucaceae), they produce on average about 17.5 larvae of exules. Owing to natural enemies (above all true bugs of the species Anthocoris minki), aphids die in 90% of galls.

This report assesses the structural diversity of the spruce virgin forest in Nefcerka NNR in the Tatra National Park (TANAP). The structure of the virgin forest is evaluated by the indices proposed by Clark & Evans, Füldner and Jaehne & Dohrenbusch. Concerning the spatial distribution of trees (Clark & Evans index), a statistically significant difference was confirmed between the growth stage and the optimum and the breakdown stages. The influence of altitude on the tendency of concentration of virgin forest trees was also confirmed. In the case of complex diversity evaluation by the JAEHNE & DOHRENBUSCH index (1997), a statistically significantly different diversity of the spruce virgin forest between the growth stage and the other stages was found. The analysis of the regeneration processes revealed their good dynamics even at an altitude above 1,400 m, and with the ascending altitude (above 1,300 m) the dead wood and knolls of wind-thrown roots have the greater importance as seedbeds.

Psocid (Psocoptera) taxocoenoses were studied in forest ecosystems of the Western Carpathian Mts. in 1997-2001. As a study frame, vegetation tiers (VT = altitudinal vegetation zones) of geobiocoenological or forest-typological system were used. Lower units of forest typological system (forest type complexes) were used for the classification of ecological conditions and the material found in forest ecosystems of Abieti-fageta s. lat. communities (5^th fir-beech VT) was evaluated in detail. This VT is the most widespread in the regions under study (the Moravskoslezské Beskydy Mts., the Vsetínské vrchy Hills and Javorníky). 2,023 adults comprising 28 species were found in the 5^th VT. Caecilius burmeisteri was found as eudominant species; Philotarsus picicornis, Caecilius flavidus and Peripsocus subfasciatus were found as dominant species. In natural geobiocoenoses with the level of naturalness 1 or 2, the following species were found: Mesopsocus unipunctatus, Caecilius flavidus, and Caecilius burmeisteri as eudominant and Caecilius despaxi as dominant. Taxocoenoses of psocids were evaluated by Detrended Correspondence Analysis (DCA) and Divisive Cluster Analysis (DvClA). The axes were interpreted in DCA-analysis as follows: the x-axis denotes the influence of VTs and the q-axis refers to the influence of hydricity. This material was compared with other material obtained from various vegetation tiers in the Western Carpathians Mts. The characteristic species composition of psocids in the 5^th VT was as follows: Caecilius flavidus - C. burmeisteri - C. despaxi - Metylophorus nebulosus - Philotarsus picicornis.

The paper shows difficulties in the evaluation of the forest status when considering forests with different height structure (uneven-aged forests). It is the main problem in categorizing such forests. Concerning the actual forest management conception in Slovakia, it is assumed that the area of forests with close-to-nature management system will increase. It leads to more structured forests, as for the tree species, age, height, as well as the spatial structure. The typical vertically homogeneous forests account for only 50% of all Slovak forests, according to results from the National Forest Inventory in Slovakia (NFI SR). During the processing of NFI data the stands were divided into 2 classes as follows: (i) vertically homogeneous stands, which are classified into nine growth stages; (ii) vertically heterogeneous stands, which are classified into two growth stages (lower and advanced), and stands in the process of regeneration. New approaches are not based on the visual subjective estimation of forest homogeneity, but on objective analyses of measured values from inventory plots (tree heights, diameters, and age). The paper shows a new approach to the classification of forest stands on an example of the variability of measured heights on inventory plots from NFI.

Artificial regeneration of autochthonous target tree species plays an important role in the process of conversion of forest stands. The European beech is one of the most suitable and most frequently used tree species in this process. Modern technologies of intensive methods of the cultivation of the European beech seedlings provide, among others, a possibility to increase the proportion of this tree species in reforestation more quickly. It is however necessary to test at what types of sites this planting material can be used. The health status and growth of intensively grown beech seedlings in the first years after planting were studied on 2 research plots. Proper intensive fertilisation of the beech seedlings affected positively both the initial height and growth. Even the slow-release fertiliser did not negatively influence the beech after planting. The health status of the beech is excellent after 4 years, the average height of plants with different fertilisation treatments having become equal. It is to conclude from the hitherto obtained results that a slow-release fertiliser in the substrate has a positive effect on the plant growth, and that different fertilisation variants did not cause any serious root deformations of the beech planting stock samples taken 4 years after planting. The impacts of prior nursery fertilisation upon the beech planted under the conditions of extreme sites are further investigated.

The present paper is the first contribution from the biomass quantification series which is realized by Forestry and Game Management Research Institute in the Krušné hory Mts. (Northern Bohemia). This study is aimed at blue spruce substitute stands. Research was done within the blue spruce experiment Fláje II in the Krušné hory Mts. (800 m above sea level in the spruce forest vegetation zone, acidic category). Results showed that the aboveground biomass of the investigated substitute blue spruce stand without thinning amounted to approximately 56 thousand kg of dry matter per ha at the age of 22 years. Wood and bark of branches are the most important parts of the aboveground biomass (ca 40%). Needles and stem wood accounted for approximately 26 and 28% and stem bark only for 6%. At the age of 22 years, the investigated substitute blue spruce stand accumulated: N - 336 kg, P - 28 kg, K - 138 kg, Ca - 159 kg, Mg - 28 kg per hectare. Thinning with the consequent removal of aboveground biomass (54% of trees, 40% of basal area at the age of 16 years) represented a loss of ca 8.7 thousand kg/ha of total biomass, which contained 53 kg of N, 5 kg of P, 22 kg of K, 26 kg of Ca and 4 kg of Mg. The removal of biomass in areas previously degraded by acid deposition may result in the deficiency of Ca and Mg because of their low content in forest soil. On the other hand, thinning supported the faster growth of trees left after thinning and consequently faster biomass and nutrient accumulation.

The uniqueness of limestone soil-forming substrate was assessed with respect to the classification of forest ecosystems. 50 soil profiles from the Bohemian Karst were studied and the results were confronted with previously published works from other karst areas. The evaluation of soil profiles was based on a macroscopic description, on the results of chemical and physicochemical analyses, and on a micromorphological study. The carbonate bedrock was a cause of specific genesis of soils in these sites - both recent and relict ones (terrae calcis). However, it does not always condition the unique characteristics of these sites whose differentiation would call for an a priori special edaphic category. Unique geochemical characteristics of the substrate are modified on the gradient of advanced pedogenesis (Holocene up to mid-Pleistocene soils were assessed) by a very intensive soil-forming process connected with the impact of allochthonous, mostly aeolian material. Two possible approaches were designed for the classification of these sites: (i) wider conception - distinction of the basic edaphic category with small limitations for the quality of soil-forming substrate, (ii) narrower conception - limestone edaphic category with a number of limitations to distinguish this edaphic category.