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Information on the historical background of the present forest conditions is needed for proper decisions on forest management. Disturbances play a major role in the formation of forest structure and composition. This paper compares the present break-up of mountain spruce stands in the Bohemian Forest (in the Šumava Protected Landscape Area) with conditions during their initiation using dendrochronological techniques. On three selected localities we established two study plots within relatively old stands of unknown origin. Stands were recently broken up by a windstorm. The present situation was described by diameter and decay class distribution. To describe the situation at the stand initiation, we cored at least 40 stems on each plot to get the age structure and growth series of trees. Disturbances were marked by discovering synchronous releases on tree-ring series. Main population waves were initiated in association with severe disturbances during a relatively short period, leading to the establishment of relatively even-aged, homogeneously looking stands. The disturbances were synchronized between plots and accounted for by historically known windstorms or bark beetle outbreaks; notwithstanding, logging as a disturbance factor is also particularly possible.

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 mycological conditions on study plots established in forests growing on former agricultural farm lands were studied. In young spruce stand (8-10 years) reduced and unstable spectrum of macromycetes was found. After approximately 50 years of forest growth the situation became stable and spectrum of macromycetes together with development of mycorrhizal status were similar to a situation found in stands on forest soils. Slightly increased occurrence of saproparasitic species of fungi (e.g. Heterobasidion annosum at others) was observed in older growths.

The aim of this study was to compare the degree of root rot damage in two large complexes of Norway spruce stands established on former agricultural land at fertile sites. The root rot infection was observed on the stump cutting area on both intended and salvage clear fellings. Stands in Kružberk area in the Nízký Jeseník Mts. established on arable land showed very poor stability and large root rot damage at the age of 40-50 years. In contrast, stands in Lužná area in the Javorníky Mts., founded on former sheep pastures, were markedly much less damaged at the age of 90-110 years and proved to be able to provide quality timber, although they were damaged by the root rot as well.

: The paper describes the basic potential methods and their costs of maintenance of forest lands in protective zones under high-voltage power lines (HVPL) 400 kV and 220 kV. In the present situation and with available information and data, it was possible to accomplish the average cost calculations for the whole area of the Czech Republic. The paper analyses the following mechanical and chemical methods of maintenance of forest lands: full-area scrub clearing with power saw (PS), selective individual scattered clearing of trees with PS, full-area scrub clearing by milling, full-area scrub clearing by the application of herbicides and arboricides, selective individual scrub clearing of individual trees by cutting followed by spray treatment with arboricides. The maintenance of forest lands in zones of HVPL (scrub clearing) by milling belongs to the economically most convenient mechanical methods, for example when removing 3,000 trees.ha^-1, the cost of this option is 20,000-23,000 CZK.ha^-1ha in a period of 3-year periodic frequency, while the most expensive method is selective individual scrub clearing of scattered individual plants with PS at costs of around 84,000 CZK.ha^-1.

The influences of long-term flooding and Phytophthora alni subsp. alni infection on the growth and development of 4-year-old Alnus glutinosa (black alder) saplings were investigated. The black alder saplings were divided into four groups and then subjected to combinations of both factors - flooded and inoculated with pathogen, flooded non-inoculated, non-flooded inoculated, and control. The biomass of the living roots and actinorrhizae, increase in stem length, length of leaves, rate of chlorotic foliage, amount of foliage biomass and length of stem necrosis were assessed after seven weeks. Both factors, flooding and P. alni infection significantly affected the black alder. In addition, a significant effect of interaction was observed. The inoculated flooded group had a substantially lower biomass weight of living roots, actinorrhiza and leaves than the other groups. The necroses caused by the pathogen in the flooded group were more extensive than those in the non-flooded one. These findings demonstrate that the simultaneous incidence of stress caused by flooding and P. alni infection is highly dangerous for black alder.

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.

The aim of this paper is to show the application of pine bark to indicate the level of air contamination by cement-lime dust and to determine the impact range of cement plants. The pine bark was analyzed in the forested formed around three cement plants in the Świętokrzyski administrative district (South of Poland). The test results were compared with the results gained from the controlled forested areas, free from alkali contamination. The strongly alkali areas show high pH_H2O of bark in the range of 7.2-8.5 and low coefficient of change v% = 2.2. The pine bark values of pH_H2O in the alkali areas are on average 2.5 times as high as those achieved in the controlled area (natural pH of bark shows the range of 2.8-3.5). On the basis of the measurements of pH_H2O there are five alkali-forested spheres determined. The existence of the forest spheres confirms the variable mineral composition of the bark, and first of all the variable content of calcium, magnesium, potassium, aluminium, manganese, zinc and iron as a function of the distance from the emitter and real dust fall.

Five types of stand stages (clearings-samplings, plantations, thinnings, thickets, and mature forests) of spruce forests were examined at the foothills of the Jizerské hory Mts. in summer 2005 and 2006. The presence of ants was surveyed by catching them into pitfall traps and observing on baits. Higher numbers of Formica fusca ants were found in clearings-samplings and in plantations. Their activity was higher at the soil and air temperature of 20-30°C. The peak of activity was observed in July. Most specimens were trapped at lighter habitats and in the sites with more than 50% herbaceous and gramineous vegetation cover. F. pratensis was trapped in plantations and thickets. It was active at the soil temperatures 12-21°C and air temperatures 16-25°C. It occurred both in dark and light areas. F. sanguinea most commonly occurred in thinnings. This species was the most active at the soil temperature 20-30°C. Its activity depending on air temperature grew almost linearly. It occurred both in dark and in light stand stages with at least 60% vegetation cover. F. truncorum was observed only in thinnings. The activity of F. truncorum was the highest at the air and soil temperatures 15-25°C. The peak of activity was recorded in July. It was observed only in stands with the quantity of incident radiation 1,030 lx and with 20-80% of undergrowth cover.

The impact of blue spruce (Picea pungens) and reed Calamagrostis villosa) cover on quantity and quality of upper soil layers was investigated. The research was conducted in the Jizerské hory Mts., Czech Republic (altitude 880 m, acidic spruce forest site type - 8K). Mean weight of dry matter of holorganic horizons was similar under both variants. Totally, there were accumulated 153 t/ha of dry matter of humus horizons in blue spruce and 174 t/ha in reed. Soil pH (KCl) varied from 3.7 to 3.2 under blue spruce stand and from 3.6 to 3.3 under reed. The differences of concentrations of nutrients (P, K, Ca, Mg) were not found significant either. Only L horizon showed significant differences: there were higher values of cation exchangeable capacity (T) and higher content of exchangeable bases (S) under reed. We found very similar forest-floor humus properties under both species. Therefore we can not state worsening of the soil conditions under blue spruce compared to areas covered with tested forest weed species.

Beech (Fagus orientalis Lipsky) is the most industrial commercial tree species among more than 80 broadleaved trees and shrubs in Hyrcanian forests. In this study some of the silvicultural properties of beech were studied under a shelterwood cutting system in a regeneration unit of 25 years old stand in Sangdeh forests of Iran. Tree height, diameter, canopy cover, variety of species, frequency at different stages of growth (seedling, sapling, thicket and pole) and tree density at juvenile phase were recorded in 431 circular 1,000 m² sample plots before and after shelterwood cutting. Results indicated that tree density in the diameter at breast height (dbh) class of < 20 cm increased during shelterwood cutting. Canopy cover of regeneration unit was 78.5% in 1957, while in 2000 and after the shelterwood cutting it reached 59%. Growing stages of regeneration were 14% sapling, 21% thicket, 24% small pole and 41% pole. The shelterwood method has not been very successful in our study area due to a number of technical and potential problems.

Effective forest management demands detailed knowledge of resources. Local forest users are usually the best source of information. In the Democratic Republic of Congo forest management partnerships between local people and government staff have become more common. A proper understanding of local perceptions of the forest is needed. This study was designed and guided by a multidisciplinary team including a sociologist, a linguist and a forester. It identified and compared classification and management units. It also touched on the different uses of the forest products, the species that provided these products and the locations of these species.

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.

Digital terrain model (DTM) represents a very important geospatial data type. In the CzechRepublic, the most common digital contour data sources are the Primary Geographic Data Base (ZABAGED), the Digital Ground Model (DMÚ25) and eventually the Regional Plans of Forest Development (OPRL). In constructing regular raster DTM, the initial process requires interpolation between the points in order to estimate values in a regular grid pattern. In this study, constructions of DTM from the above-mentioned data were tested using several software products: ArcEditor 9.0, Atlas 3.8, GRASS 6.1, Idrisi 14.02 and TopoL 2001. Algorithm parameters can be optimized in several ways. In this sense a comparison of the first and second derivative of DTM and its real appearance in the terrain and a cross-validation procedure or terrain data measurements to compute and minimize the root mean square error values (RMSE) proved to be the most useful operations. The ZABAGED contour data provided the best results, with software specific algorithms for interpolations of contour data (ArcGIS Desktop Topo to Raster, Idrisi Kilimanjaro TIN).

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 paper deals with historical development of floodplain forests in the area of Vrapač National Nature Reserve in the floodplain of the Morava River (Protected Landscape Area Litovelské Pomoraví, Czech Republic). The aim of this paper is to contribute to a better understanding of the anthropogenic influences that have over centuries led to the present state of floodplain forests in the study area. Thus, it will be possible to define more efficiently the management plan of this floodplain forest ecosystem.

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 basic condition of forest management development is the accessibility of the forest. A design of the forest road network in relation to all-society functions of forests has been made in the catchment of the Vilčok stream. The catchment is situated in Protected Landscape Area Beskydy. The method Quantification and quantitative evaluation of functions of forests as a basis for their evaluation (Vyskot et al. 2003) was used for the design. This method can be applied to road planning. It can serve as another component in the decision-making process of the planning of forest road construction.

The article investigates the socio-economic importance of collection and use of non-wood forest products (NWFP) for inhabitants in the Czech Republic (CR) in 2005 and brings a comparison with former investigations and research projects. The research project consisted of these parts in 2005: 1. Analysis of hitherto performed research projects and their results in 1999-2003, 2. Investigation of quantities and values of NWFP collected in 2004 and 2005, 3. Specific investigation of socio-economic importance of NWFP collection and use. The results of respective investigations prove NWFP collection being quite important for the inhabitants of the CR. The importance consists in the material value of picked commodities on the average annual level higher than 3,000 mil. CZK. Nevertheless, collecting NWFP is considered as a very important recreational activity. Only a small part of the population collecting NWFP (about 12%) collects NWFP to save money.

Frisol forte (FR F) and Frisol active (FR A) are slow-acting organic fertilisers recommended for reclamation and revitalisation of undeveloped soils and degraded areas. Tentative results of experiments carried out with these products on spoil banks in the CR showed controversial reactions of plants - on the one hand a high mortality of seedlings and a very good growth on the other. Reasons for these disproportions projecting themselves into the welfare of woody plants probably lie in an incorrect dosage of products. Thus, a special long-term experiment was established with the objective to find an optimal dosing to be used in practice for the reclamation process on spoil banks. By the method of measuring and statistical evaluation of height and stem diameter growths it was discovered that the best results were achieved by the combined use of both products with a dosage in the range of 30-60 g FR F + 250 ml FR A/5 l of water/10 seedlings. The discovered dosage is lower than that indicated by the manufacturer and literature. The application of granulated FR F alone was not so effective. The best dosage in this case was also 60 g/seedling. A disadvantage of using the combination of both types of Frisol is that the water required for dissolving the FR A liquid concentrate is not always available in the location being reforested.

At present, photogrammetric interpretation of aerial images is a dominant method of forestry mapping. In the last years, transition from analogue to digital photogrammetry has been distinct. Digital photogrammetry enables to achieve workflow effectivity, and so to decrease the final product costs. The objective of the submitted paper was to evaluate the availability of digital photogrammetry for the forestry mapping rationalization. Digital aerotriangulation using the ImageStation SSK system brings more accurate results without requirements for the use of a larger amount of control points. The results also demonstrated the use of colour infrared aerial images, and also black and white aerial images at the scale 1:15,000 for the orthoimage creation in the forestry mapping department. Compared with the black and white aerial images, the colour infrared images have an essentially more interesting content, mainly from the qualitative aspect, which shifts them to use in many forestry disciplines (mostly for determination of the health conditions of forests stands, …), in combination with the remote sensing of the Earth and GIS (Geographic Information Systems).

The objective of the study was to evaluate the growth potential of Carpathian birch (Betula carpatica W. et K.) at an environmentally harsh mountain site and a response of this species to altered soil chemistry after dolomitic limestone and basalt grit applications. The Carpathian birch proved to be a suitable species for the replanting of extreme acidic mountain sites. This birch shows a low mortality rate, grows well in the clear-felled patches and soon forms a cover which is necessary for the reintroducing of more sensitive tree species. The application of dolomitic limestone and basalt grit resulted in the slower growth of Carpathian birch plantations. Liming raised soil reaction, sum of exchangeable bases, base saturation, cation exchange capacity and reduced exchangeable Al content. On the other hand, liming decreased an amount of oxidizable soil organic matter and negatively affected soil N, exchangeable P and K. Basalt grit increased exchangeable P and K contents and raised soil reaction, however only slightly. The influence of basalt grit on the sum of exchangeable bases, base saturation and cation exchange capacity was also less pronounced compared to liming. Basalt grit elevated the proportion of exchangeable aluminium and reduced the content of soil N.

Manipulated experiments with males of Ips typographus (L., 1758) were conducted in spruce stands in north-western Slovakia. Some of trees were stressed by a lack of water caused by preparation of roofs under canopy. Inoculation experiments with bark beetles were conducted on such trees. According to results, the differences in attack rates between differently positioned trees on slope were not statistically significant (P = 0.389 for bottom and middle and P = 0.924 for bottom and top, and P = 0.530 for middle and top trees, t-test). Also the differences in attacks rate and the speed of entry holes preparation between more stressed and less-stressed trees were not statistically significant (P = 0.321, t-test). Thus the results of inoculation confirmed that low level of water stress does not lead necessarily to higher attack rate and (neither) faster speed of entry holes preparation. The obtained results are discussed.

A dramatic forest decline due to the bark beetle outbreak, which occurs in the Norway spruce stands in the Western Beskidy (southern Poland) since 2003, was started after severe physiological drought during winter time. An analysis describing some spatio-temporal characteristics of this process, with special regard to the patterns of bark beetle occurrence related to root fungal diseases, is presented. In 2003 the bark beetle occurrence level assessed as high and catastrophic was recorded on 40% of the area, while in 2006 - on 59%. The range of Armillaria root disease and bark beetle outbreak increased towards higher altitudes, including the zone above 1,000 m a.s.l. The wind damage in 2004 and 2007, and high temperatures in the summer 2006, further stimulated the increase in bark beetle populations level. Some conclusions on possible development of the outbreak and recommendations concerning related needs in forest protection, are given.

This article presents a review of data and results of investigations from the period 1958-2006 regarding the occurrence of insects of the genus Cephalcia Panzer (Hymenoptera, Pamphiliidae) in Norway spruce stands of the Beskidy Mountains (Western Carpathians, southern Poland). Currently, eight species are known for the area: C. abietis, C. alashanica, C. alpina, C. annulicornis, C. arvensis, C. erythrogaster, C. fulva and C. masuttii. Information regarding each species is given, with details on identification, local occurrence and importance.

Emissions and ecological factors are evident in changes of dynamics of global forest ecosystems. Specific develop-ment takes place in these substitute stands on contaminated and devastated plots. The aim of this study was to solve a problem if forest stands were able to indicate its real natural potential in these anthropogenically influenced conditions. In ten substitute stands on experimental plots samples were taken in autumn 2002 from H-horizons and A-horizons and phytocoenological relevés were taken in the area of the firm Městské lesy Trutnov (Poříčský hřbet Plateau, 530 m a.s.l.; +6.9°C; 671 mm). A hypothesis that the combination of herbaceous species can significantly indicate pH/H₂O and pH/KCl was tested.

Dokumenty týkajúce sa regulácie hospodárenia v lesoch sa prakticky až dodnes považovali za materiály, týkajúce sa skoro výlučne len jednotlivých odborných rezortov. Na základe Vyhlášky Ministerstva financií SR č. 465/1991 ich možno efektívne využívať aj v rámci rezortov financií a spravodlivosti. Ďalšie významné medzirezortné využitie týchto dokumentov vyplýva zo Zákona č. 127/1994 o posudzovaní environmentálneho dopadu. Cieľom práce je demonštrovať proces posudzovania na konkrétnom príklade - ploche patriacej do lesného pozemkového fondu. Okrem máp, výsledkov pozorovania, slovných popisov a súborov numerických údajov, týkajúcich sa jednotlivých porastov, obsahujú tieto dokumenty aj kódované údaje, ktoré pre väčšinu užívateľov nie sú zrozumiteľné bez využitia dekódovacích kľúčov. A práve tieto posledné údaje majú pri vyhodnocovaní environmentálneho dopadu najvyššiu výpovednú hodnotu. Po nadobudnutí platnosti pripravovaného zákona (vyhlášky) o strate vlastníctva, vyplývajúcej z prohibitívnych a ďalších podmienok v lesnom hospodárstve v súvislosti s presadzovaním verejno-prospešného záujmu (Kundrík et al. 1999), významne vzrastie dôležitosť využitia finálnych dokumentov týkajúcich sa regulácie hospodárenia v lesoch SR.

This paper describes the automated classification of tree species composition from Ikonos 4-meter imagery using an object-oriented approach. The image was acquired over a man-planted forest area with the proportion of various forest types (conifers, broadleaved, mixed) in the Krušné hory Mts., Czech Republic. In order to enlarge the class signature space, additional channels were calculated by low-pass filtering, IHS transformation and Haralick texture measures. Employing these layers, image segmentation and classification were conducted on several levels to create a hierarchical image object network. The higher level separated the image into smaller parts regarding the stand maturity and structure, the lower (detailed) level assigned individual tree clusters into classes for the main forest species. The classification accuracy was assessed by comparing the automated technique with the field inventory using Kappa coefficient. The study aimed to create a rule-base transferable to other datasets. Moreover, the appropriate scale of common image data and utilisation in forestry management are evaluated.

By means of computer-based image analysis it was possible to accelerate and automate a number of originally time-consuming activities in plant pathology and forest protection. In 1997-2005, image analysis was applied to the measuring of the size of colonies of fungi in vitro, feeding mark area, mass measuring of the size of spores and other microscopic objects, assessment of the progress of rot in a stem etc. The paper brings particular examples of the application of image analysis including methodical procedures and examples of research results obtained using Lucia G and Quick Photo Micro programs.