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Results 391 to 420 of 525:

Root system development and health condition of sycamore maple (Acer pseudoplatanus L.) in the air-polluted region of Krušné hory Mts.

O. Mauer, M. Pop, E. Palátová

J. For. Sci., 2007, 53(10):452-461 | DOI: 10.17221/2086-JFS

The paper presents results from a study of sycamore maple development, health condition and growth in forest altitudinal vegetation zones (FAVZ) 6 and 7 occurring in pollution damage zones A and B in the air-polluted region of Krušné hory Mts. as compared with the trees of identical height in FAVZ 4 and 5 occurring in pollution damage zone D in the Bohemian-Moravian Upland. Sycamore maple develops a fully diversified root system. On spread mounds it creates only a superficial root system and its growth is retarded. The growth of sycamore maple is limited by the layer of humus horizons. If the layer thickness is over 20 cm, the sycamore roots would grow into mineral horizons.

Historical development of floodplain forests in the Upper Moravian Vale (Vrapač National Nature Reserve, Czech Republic)

I. Machar

J. For. Sci., 2008, 54(9):426-437 | DOI: 10.17221/46/2008-JFS

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.

Influence of human factor on the time of work stages of harvesters and crane-equipped forwarders

J. Dvořák, Z. Malkovský, J. Macků

J. For. Sci., 2008, 54(1):24-30 | DOI: 10.17221/790-JFS

Harvester technologies represent the second most common logging system in the Czech Republic. The high productivity of this technology is very necessary to cover its acquisition and operational costs. A human factor - a machine operator is the most important factor that surely influences the machine productivity. That is why the aim of this study is as follows: to analyze the mutual dependence of machine operator's education and working experience and harvester and forwarder productivity. The analysis proves that the operator's education and even more his working experience are very important. The time of harvesting work stages was measured when the harvester was operated by an operator with two-year working experience and by an operator with no experience. The average time difference between the harvester operators was 64.9 seconds in one work stage. The statistical significance of different operation times was confirmed during technically demanding segments in the working stage (the boom out the felling head and tree processing). Operators with the same working experience in forestry mechanization - about 13 years but with different education carried out the haulage work stage. In this case, the statistical significance between calculated differences was not proved. This fact proves that the operator's working experience is more important than his education.

Comparison of general tree characteristics of less known oak species Quercus dalechampii Ten. and Quercus polycarpa Schur

R. Matula

J. For. Sci., 2008, 54(8):333-339 | DOI: 10.17221/3096-JFS

This study was designed to evaluate basic tree characteristics of Quercus dalechampii Ten. and Quercus polycarpa Schur and to find out differences between them. Total height, height of crown base and diameter at breast height were measured before tree felling. Cut stems were visually checked for heart rot on their basal parts. Diameters were measured on each stem in 1 meter long sections from the base to the point of life crown setting. Average values for both species were compared by t-test. The total height was proved to be statistically different; the height of crown base and diameter at breast height were quite similar for both species. Q. dalechampii Ten. was proved to be of larger stem diameter from the tree foot to the 3rd height meter; the diameter of Q. polycarpa Schur was superior from that height upwards. However, the most significant interspecies difference was found in a number of stems affected by wood-rot fungi as Q. polycarpa Schur turned out to be less resistant than Q. dalechampii Ten.

A change in structural diversity and regeneration processes of the spruce virgin forest in Nefcerka NNR (TANAP) in relation to altitude

J. Pittner, M. Saniga

J. For. Sci., 2008, 54(12):545-553 | DOI: 10.17221/21/2008-JFS

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.

Intensively fertilised seedlings of the beech (Fagus sylvaticaL.) for artificial regeneration of the spruce stands in the process of conversion

A. Jurásek, J. Bartoš, J. Nárovcová

J. For. Sci., 2008, 54(10):452-458 | DOI: 10.17221/41/2008-JFS

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.

Floodplain forests of Litovelské Pomoraví and their management

I. Machar

J. For. Sci., 2008, 54(8):355-369 | DOI: 10.17221/27/2008-JFS

The paper characterizes the natural conditions and current state of floodplain forests in the area of Litovelské Pomoraví and proposes the protective management of the area in accordance with the European Natura 2000 system. The paper describes the geographical location and the natural conditions of the area of interest (climate, geology, geomorphology, hydrology and flood regime, soils, and vegetation). Six groups of geobiocene types were identified, classified and described in detail. Assessment of the ecological stability of the forest stand was carried out using biogeographical differentiation of the landscape and the outline of the forest ecosystem management is drawn based on the differentiation of the protected landscape area into zones with various levels of protection.

Conversion of even aged forest managed under the system involving coupes to selection forest in Klepačov

J. Šilhánek

J. For. Sci., 2008, 54(10):465-475 | DOI: 10.17221/53/2008-JFS

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.

Contribution to the knowledge of Apodemus sylvaticus populations in forests of the managed landscape of southern Moravia (Czech Republic)

J. Suchomel

J. For. Sci., 2008, 54(8):370-376 | DOI: 10.17221/33/2008-JFS

The population dynamics of wood mouse (Apodemus sylvaticus) was studied in three forest complexes differing in food supply in the intensively managed landscape of southern Moravia. They included an old semi-natural floodplain forest dominated by oak (HL), production broadleaved forest with the predominance of oak and robinia (HA) and a pheasantry with various forest stands consisting of diverse species and age categories of trees with a quantity of additional food for additional feeding of pheasants and roe deer (RB). The population fluctuation within six-year monitoring was affected by seed years (acorn crops in 2003 and 2006), which resulted in an increase in the species population density in the next year. Statistically significant effects of the crop of acorns on the body weight of monitored species were also detected (P < 0.01, F = 1.44). Relative abundance differed significantly between the floodplain forest (HL) and RB and HA (P < 0.01). The two last-mentioned sites did not differ and only a trend of greater preference to the most variable biotope in RB was noted. It evidences the unsuitability of floodplain forest for the species. In spite of the food specialization in small seeds significant effects of the excess crop of acorns can result in a rapid increase in the Apodemus sylvaticus population which can then cause damage to the natural regeneration of oak or artificial regeneration by seeding although to a substantially smaller extent than the more harmful A. flavicollis.

Changes in Austrian pine forest floor properties in relation with altitude in mountainous areas

O. Sevgi, H. B. Tecimen

J. For. Sci., 2008, 54(7):306-313 | DOI: 10.17221/819-JFS

Altitudinal studies has become of interest to ecologists concentrated on functional alterations aiming to clarify the effects of limiting factors. Nutrient element release from forest floor (FF) decomposition is suppressed by those factors such as low temperature, shortened vegetation period concluding FF accumulation at high elevation fields. To draw out a response to the FF decomposition issue, FF layers as leaf + fermentation (L + F) and humus (H) were collected from 37 representative sample plots along an altitudinal gradient (from 1,400 m to 1,710 m) on Kaz (Balikesir-Turkey) mountain. Mass, pH, organic matter (OM) and total nitrogen (Nt) contents of FF were investigated to explain the relation between decomposition and altitudinal effects. The results revealed that total FF mass and (L + F), (H) sub-fraction masses through elevation show an insignificant relation with the altitude. No significant difference was found between the altitudinal groups in the OM content of L + F. Besides there are significant negative correlations between OM contents (%) of L + F and H layers and altitude with the coefficient values 0.342 (P< 0.05) and 0.597 (P < 0.01), respectively. The Nt content of L + F layer also increases through the elevation revealing a medium correlation with altitude (0.368; P < 0.05). The increasing Nt and decreasing OM contents show better decomposition rates at higher sites regardless of the altitude induced climatic changes. We assume that the forest floor accumulation under tree canopies provides a better decomposition relying on the microclimatic environment mediated by tree canopies, in spite of the altitude.

Fine root growth of beech (Fagus sylvatica L.) seedlings during the first outplanting years in Western Bohemia (Czech Republic)

M. Skrziszowski, I. Kupka

J. For. Sci., 2008, 54(5):212-215 | DOI: 10.17221/2901-JFS

The study analyses the growth of beech seedling fine roots and their development in the first five years. The research plots were established in 1997-2003 in community forests of Starý Plzenec (Western Bohemia, Czech Republic). The data are based on annual reviews of beech samplings extracted from surveyed plots. The whole root volume as well as the fine root volume is significantly (on a 95% significance level) growing during the first years after outplanting and there is not any disruption of growth immediately after outplanting.

Architecture of root branches of Norway spruce trees (Picea abies [L.] Karst.) growing in gley soil

P. Štofko, M. Kodrík

J. For. Sci., 2008, 54(11):485-490 | DOI: 10.17221/55/2008-JFS

In the locality Hnilé Blatá (the High Tatras Mts.), the structure was measured of root branches in the windthrown spruces (Picea abies [L.] Karst.). After cleaning the root plates, the number, diameter, and length of individual root branches were measured. Individual root branches were classified into twelve diameter classes - according to their diameters measured in the middle of the root branch length. We found out a high frequency of the root branches in the first three root-diameter classes; the values of the average frequency of root branches smoothly declined with their diameters increasing. We found out the lowest mean values of the root branch length in the first two root diameter classes. However, the values of total average length of root branches were the highest in the first root diameter class and these values continually decreased with increasing values of the root branch diameter. On the basis of the high values of root frequency and of total root length in the thinnest root-diameter classes, it seems that the spruce trees growing in gley soil form a similar root structure as those growing in podzolic brown soil.

Nutrients in the aboveground biomass of substitute tree species stand with respect to thinning - blue spruce (Picea pungens Engelm.)

M. Slodičák, J. Novák

J. For. Sci., 2008, 54(3):85-91 | DOI: 10.17221/3032-JFS

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.

Analysis of the production potential of raw wood in the forests of Slovakia

R. Petráš, J. Mecko

J. For. Sci., 2008, 54(7):314-320 | DOI: 10.17221/10/2008-JFS

Production of raw wood material and its regulation has a great ecological and economic importance in every country. The aim of the paper is to analyze the prospective production of raw wood with respect to the expected basic tree species composition and assortment structure on an example of long-term development of selected indicators of forest condition in Slovakia. For this analysis we used data on the area, growing stock and planned decennial timber felling in the forests of Slovakia in 1980, 1996 and 2003. The production potential of forests was evaluated on the basis of the annual perspective allowable cut by 2020, from which the prospective production of assortments was derived using the models of assortment yield tables of tree species. The results show that in the forests of Slovakia there is an about half proportion of coniferous and half proportion of broadleaved tree species, very good structure of growing stock as well as its trend in the last years. Production of raw wood assortments for industrial processing for the years 2010-2020 is limited by the volume 6.3-6.4 mil. m3. About one half of this volume comes from coniferous and the other half from broadleaved tree species. For coniferous tree species the proportion of spruce and fir is 87% and for broadleaved tree species the proportion of beech and oak is 80%. For coniferous tree species sawmill assortments have a decisive, almost 70% proportion. Regarding broadleaved tree species, pulpwood assortments with 47% proportion prevail, although with 11% the highest quality assortments for the production of veneer from beech and oak are also significant.

Models of assortment yield tables for poplar clones

R. Petráš, J. Mecko, V. Nociar

J. For. Sci., 2008, 54(5):227-233 | DOI: 10.17221/3/2008-JFS

The results of research on the production of raw timber assortments for the stands of poplar clones Robusta and I-214 in Slovakia are presented in this paper. Models of assortment yield tables were constructed, separately for each clone, in dependence on the yield class and stand age. The construction was based on the models of yield tables, stand assortment tables, models of external quality and damage to stems. Robusta clone produces by about 15-20% higher proportions of the highest quality assortments than I-214 clone. I-214 clone produces faster and higher proportions of average- and below-average quality assortments.

Growth and health state of silver fir (Abies alba Mill.) in the ridge area of the Jizerské hory Mts.

V. Balcar, D. Kacálek

J. For. Sci., 2008, 54(11):509-518 | DOI: 10.17221/63/2008-JFS

The silver fir was planted under mountain conditions in order to reveal its response to the addition of finely ground rocks (limestone and amphibolite) mixed with soil into the planting holes. The results document that the increments of the plantations fertilised with amphibolite were higher by 25% on average than those of the control plantations while the increments of the plantations treated with dolomitic limestone were lower by 13%. Generally, as concerns both the plantations with the application of ground rocks and the control ones, the development of the fir plantations in 1994-2007 is considered successful. As the damage by climatic stresses has gradually diminished, the number of dead trees has been decreasing and the height increments have been increasing in the last years, therefore a positive development is to be expected also in future.

Biological activity, nitrogen dynamics, and chemical characteristics of forest soils in the Šumava national park

M. Svoboda

J. For. Sci., 2003, 49(7):302-312 | DOI: 10.17221/4704-JFS

This paper deals with large-scale mountain forest decline in the Šumava National Park. The changes in biotic and abiotic properties of forest sites follow the tree layer disintegration. Changed microclimatic conditions such as intensity of irradiance, moisture and temperature of the top holorganic layers together with altered development of ground vegetation could strongly affect the values of microbiological respiration activity and the rates of nitrogen mineralization and nitrification. Soil substrates, built of organic mater, located on stony locations, are endangered by introskeletal erosion. This paper compares these features in pairs of research plots, consisting of dead or cut forest and of living stand. According to the results of this study, higher rates of organic matter decomposition, transformed dynamics of nitrogen and other nutrients and possible nutrient leaching from soil solutions were demonstrated in the forest floor under declined spruce stands. The extent and seriousness of these adverse processes for forest soils are strongly site dependent.

Sustainable management of mountain forests in the Czech Republic

S. Vacek, V. Balcar

J. For. Sci., 2004, 50(11):526-532 | DOI: 10.17221/4651-JFS

Forest management in the Czech Republic (CR) was not shaped in the environment of natural forests but in the territory that was influenced by unregulated felling and animal grazing for a long time. Hence the fear for sustainable and balanced benefits from forests endangered by long-term uncontrolled exploitation was legitimate. Almost after three centuries of application of the sustainability principle, forests are considered not only as a source of renewable wood raw material but also as a tool of the environment formation. Mountain forests are an important landscape component of this country. They are an object of specific importance from the aspect of natural environment conservation, stabilization of natural processes and general landscape homeostasis. In addition, they fulfil a number of production and non-production functions. Cardinal elements of sustainable forest management in the CR conditions are as follows: management of the forest as an ecosystem, i.e. transition from exclusive care of forest tree species and their stands to care of the whole forest ecosystems; restructuring (conversion, reconstruction) of damaged and declining forests; optimum (species, genetic, spatial, age) structure of forest ecosystems differentiated according to site conditions and management targets; differentiated transition from general management to group or individual methods; utilization and support of spontaneous processes such as natural regeneration, competition and other principles of self-regulation. The above cardinal elements of sustainable forest management are applicable to forests of the CR in general, but their importance considerably increases in mountain forests where many species survive on the margin of subsistence. Moreover, mountain forests of CR have been heavily destroyed by anthropogenic factors, especially air-pollution ecological stresses, during the last three or four decades.

Risk evaluation of the climatic change impact on secondary Norway spruce stands as exemplified by the Ktiny Training Forest Enterprise

P. Čermák, L. Jankovský, P. Cudlín

J. For. Sci., 2004, 50(6):256-262 | DOI: 10.17221/4623-JFS

The paper proposes a method of assessing the potential risks of the future development of stands in relation to a climatic change. To assess risks of the future development of a stand simple point scales have been worked up based on primary properties of a site and a stand according to data of the forest management plan (FMP). In assessing the health condition, the risk of damage to stands by Armillaria sp. in the felling age was evaluated on the basis of a present attack by Armillaria sp. and also defoliation of the crown primary structure assessed during a simple field examination. The evaluation was carried out in the region of the Křtiny Training Forest Enterprise (TFE) Masarykův les, ranger district Proklest, in 2002. The study was conducted in 118 Norway spruce stands aged more than 20 years. The majority of evaluated stands ranked among the category of high and medium risk from the viewpoint of site and stand risks and among the category of high Armillaria sp. attack.

Soil chemistry changes in green alder [Alnus alnobetula (Ehrh.) C. Koch] stands in mountain areas

V.V. Podrázský, I. Ulbrichová

J. For. Sci., 2003, 49(3):104-107 | DOI: 10.17221/4685-JFS

The present study documents the effects of green alder [Alnus alnobetula (Ehrh.) C. Koch] on the uppermost forest soil layers in mountain areas, respectively in the summit part of the Jizerské hory Mts. Pedochemical characteristics of holorganic horizons in stands of this species, established in 1992 on a clear-cut caused by air pollution, were compared to the status of soils in stands of bog pine (Pinus rotundata Link.). Extreme site conditions and young age of both stand types resulted in low effects on the humus forms in the first decade. Despite of this, enrichment in total nitrogen content and tendency to acidification due to nitrate leaching were obvious and statistically significant in green alder stands.

Isotope ratios and concentration of N in needles, roots and soils of Norway spruce (Picea abies [L.] Karst.) stands as influenced by atmospheric deposition of N

S. P. Sah

J. For. Sci., 2005, 51(10):468-475 | DOI: 10.17221/4580-JFS

This study aims to investigate the changes in isotope ratios in foliage and soils of two Norway spruce (Picea abies [L.] Karst.) forests greatly differing in their atmospheric N deposition and climatic conditions. As expected, both N concentrations and δ15N values in needles and roots were found to be significantly higher in the Solling stand (N-saturated) compared to the Hyytialä stand (N-poor). For both stands a typical vertical gradient of the soil 15N-enrichment was observed. As expected, the soil of N-polluted site (Solling) was 15N-enriched significantly more than that of N-limited site (Hyytialä) and this is explained by the presence of marked NO3- leaching at the Solling site. Although the annual trends (1990-1994) of N concentration in the foliage of spruce trees remained almost constant, their δ15N values significantly decreased with the increasing years of sampling. The 15N-depletion in spruce needle litter from 1990 to 1995 was by 2.0‰. This is explained by a slight decrease in N deposition at Solling site during this period.

Forest decline and pedobiological characteristics of humus forms in the Šumava National Park

M. Svoboda, V.V. Podrázský

J. For. Sci., 2005, 51(4):141-146 | DOI: 10.17221/4552-JFS

Humus forms dynamics and characteristics of different forest sites were studied in the area of Smrčina Mt. in the Šumava National Park territory. The study was performed in vital Norway spruce forest, dead Norway spruce forest (bark beetle Ips typographus infestation) and on a clear-cut area (site conditions were comparable for all three plots). The amount of surface organic matter was not affected by forest decline or by clear-cut (95.5 t/ha, 73.1 t/ha and 100.2 t/ha, respectively), pH being comparable (between 2.3 and 3.2 pH KCl). A slight favourable effect of grass litter on pH increase was obvious; higher leaching of bases occurred in lower horizons. Nitrogen losses were detected from the L + F horizons, falling from 1.93-1.83% (living stand) to 1.73-1.83% (clear-cut area). Higher ammonia production was documented in substrates (F and H horizons) from the living stand (from 263 and 103 mg/kg before incubation to 610 and 248 mg/kg after incubation - nitrogen content in ammonia form), and higher nitrification rates (nitrogen content in nitrate form) were recorded on the clear-cut area (103 and 80 mg/kg to 153 and 87 mg/kg) and especially in the dead stand (160 and 93 mg/kg to 216 and 139 mg/kg). Respective values for the living stand increased from 52 and 61 mg/kg to 119 and 84 mg/kg. Respiration activity, both potential and basic, was more balanced, indicating more intensive dynamics in the case of dead stand and clear-cut area.

Dynamics of soil temperature and its influence on biomass production of herb layer in a submontane beech forest

R. Janík

J. For. Sci., 2005, 51(6):276-282 | DOI: 10.17221/4564-JFS

The paper summarizes the results of long-term measurements of soil temperature. The measurements were performed at two depths: 5 cm and 20 cm, on a series of five experimental plots with different stocking. The temperature of soil in the submontane beech forest at the Ecological Experimental Site (EES) Kremnické vrchy Mts. reached maximum values in August, minimum ones in February. The obtained data were processed using t-test and regression analysis - to evaluate the influence of soil temperature at the discussed soil depths on the biomass production in plants. An important influence of this factor was confirmed at both depths.

Changes in tree species composition, stand structure, qualitative and quantitative production of mixed spruce, fir and beech stand on Stará Píla research plot

I. Štefančík

J. For. Sci., 2006, 52(2):74-91 | DOI: 10.17221/4489-JFS

The paper is a contribution to the research on problems of thinnings in mixed (spruce-fir-beech) stands situated in the 5th 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).

Spruce windfalls and cambioxylophagous fauna in an area with the basic and outbreak state of Ips typographus

E. Kula, W. Ząbecki

J. For. Sci., 2006, 52(11):497-509 | DOI: 10.17221/4530-JFS

In spruce windfalls incurred in the autumn and winter season the synusia of cambioxylophagous fauna was evaluated in the profile of a whole stem and crown branches according to the species spectrum, tree cover and intensity of attack. The fauna of windfalls in the area with the basic level of Ips typographus and in the gradation area differed by species diversity. In the gradation area, frequency of the occurrence of Ips typographus (L.) was higher by 20-40%. P. chalcographus (L.) showed decreased stem cover in the gradation area. In the area with the basic state of Ips typographus, windfalls were intensively colonized by secondary species Hylurgops palliatus (Gyll.), Isarthron fuscum (Fabr.), Monochamus sp. With the increasing dbh (diameter at breast height) of windfalls the colonization of stems by Ips typographus was positively affected, H. palliatus, I. fuscum, Polygraphus poligraphus (L.) responded the other way round.

The Pinus mugo complex - its structuring and general overview of the used nomenclature

J. Hamerník, I. Musil

J. For. Sci., 2007, 53(6):253-266 | DOI: 10.17221/2020-JFS

The Pinus mugo complex (P. mugo Turra sensu lato, and/or species aggregate or group - P. mugo agg., including its internal as well as external aggregate hybrids) is an important fragment of European dendroflora. For its high variability this complicated group has not been solved in taxonomical terms satisfactorily yet. Most problems are mainly caused by a large amount of taxa of uncertain value described in the past, which often more or less overlap or are based on insufficiently researched and unsuitably interpreted characters. Such facts coincidently cause further problems in applied disciplines. Specialized European literature already contains a large amount of information referring to individual taxa of this complex. Much information is listed under various, often commonly not known or not used scientific names. In order to make the information available and useful, it was necessary to collect the most frequent names used in the past and to assort them in a tabular manner into a convenient synoptic schedule respecting the present concepts of the complex and assign them with the present most commonly used names.

Processes of loss, recruitment, and increment in stands of a primeval character in selected areas of the Pieniny National Park (southern Poland)

A. Jaworski, R. Podlaski

J. For. Sci., 2007, 53(6):278-289 | DOI: 10.17221/2017-JFS

Studies were carried out during 1987-1997 in four stands situated in the lower mountain zone, and representing the association Carici-Fagetum abietetosum (sample plots Facimiech and Walusiówka) and the community of a transitory character between Dentario glandulosae-Fagetum and Carici-Fagetum (sample plots Gródek and Przelecz Sosnów). The greatest volume increment was found in a pure fir (Abies alba) stand of Facimiech (9.4 m3/ha/year, i.e. 1.4% of actual stand volume determined in 1997) being in the optimum stage, phase of aging and regeneration, and the smallest one stand of Gródek (5.3 m3/ha/year, i.e. 0.9% of actual stand volume) being in the growing up stage, phase of selection forest. The stand of Przelcz Sosnów was characterized by the greatest mortality of trees (volume of loss, i.e. 13.5 m3/ha/year). In this stand of a transitory character between the growing up and optimum stages, due to rapid mortality of fir the break up of the stand took place, and in consequence the growing up stage, phase of a little diversified stratified structure was developed. Volume of recruitment was the greatest in the stand of Facimiech, i.e. 0.05 m3/ha/year. In three fir (Abies alba)-beech (Fagus sylvatica) stands the proportions of fir and beech in stand increment differed from their proportions in stand volume. The percentage of fir in volume increment was smaller, and that of beech greater, than their percentages in stand volume. Processes of increment and mortality of fir and beech pointed to a progressive process of changes taking place in stand species composition, expressed by the increase of beech and the decrease of fir. The knowledge about values of loss, recruitment, and increment, expressed by the number of trees and volume units, may be of help in determination of the amount of cut in productive and protective forests managed according to a close-to-nature silviculture.

The root-plant ratio changes in the first growing periods of wild cherry (Prunus avium L.) plantations

I. Kupka

J. For. Sci., 2007, 53(3):113-118 | DOI: 10.17221/2147-JFS

The root-plant ratio is one of the important parameters for planting stock quality. We suppose that the ratio is one of the driving variables for the growth performance of new plantation in the forest. The study summarises data on the volume of major parts of 4 years old wild cherry trees. An allometric analysis of different parts of plants in relation to the growth performance of wild cherry trees was done. The results show a close positive relationship between the volume of the whole root system and aboveground biomass. The same is true of the fine root proportion in the root system. Data also document that the efficiency of root system is not decreasing during the root development - at least in the investigated period. The same results were obtained for fine root efficiency. Data confirm the importance of the root-plant ratio for the growth performance of new plantation in the forest provided that harmful factors are not at a limiting level.

Multifunctional forestry practices as a land use strategy to meet increasing private and public demands in modern societies

F. Schmithüsen

J. For. Sci., 2007, 53(6):290-298 | DOI: 10.17221/2016-JFS

The present distribution of forests and the degree of their transformation by man are the results of natural factors and cultural development. The limit between forested areas and open spaces, as well as differences between intensively used forests and those showing small or no traces of human intervention, is determined by social needs and values, economic opportunities, and political regulations. Forests are currently perceived by the population as physical and social spaces profoundly influenced by timber use and forest management. Their social and political significance is in full evolution. The multiple demands on forests in a rapidly evolving economic, social, and political environment require maintaining a high level of forest management standards and a flexible adaptation of multiple-use forestry to the complex interactions between the private and public sectors.

Root systems of forest tree species and their soil-conservation functions on the Krušné hory Mts. slopes disturbed by mining

P. Čermák, F. Fér

J. For. Sci., 2007, 53(12):561-566 | DOI: 10.17221/2167-JFS

The paper describes the root system architecture of the forest tree species Fagus sylvatica L., Quercus robur L., Pinus sylvestris L., Carpinus betulus L., Acer platanoides L., and Alnus glutinosa (L.) Gaertn. at the age of 80-220 years growing on the slopes of the Krušné hory Mts. at the altitude of 330 to 480 m above sea level. These species were influenced by open-pit mining of brown coal as well as by power engineeting. The investigation also involves the determination of soil properties of Ranker Cambisols.

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