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Analysis of the perceived condition of forests in the Czech RepublicOriginal PaperM. Riedl, L. ŠišákJ. For. Sci., 2013, 59(12):514-519 | DOI: 10.17221/64/2013-JFS A realistic perception of the condition of forests, and the attributes of the forestry sector, by the public constitutes one of the basic prerequisites for successful implementation of forest policy in any country. Although data objectively demonstrate that the condition of Czech forests has improved, opinion polls show a gap between the public perception of the condition of Czech forests and the real status of these forests. The reasons for the discrepancy between reality and the perception of the public, and between the results of different surveys, are analysed. The most significant differences were found in perceptions of damage and threats to forests. The effectiveness of communication about forest policy is discussed, and some ways to create more effective communication are examined. |
Specifics in the introduction of sustainability reporting by companies in the forestry sectorOriginal PaperM. Ševčík, M. Hájek, A. MikulkováJ. For. Sci., 2014, 60(6):226-235 | DOI: 10.17221/33/2014-JFS Sustainability reporting is constantly paid attention by companies for its economic, environmental and social benefits. It supports making use of the wide potential for further development of enterprises and society. Individual sectors use types of indicators that correspond to their specifics. It is also the case of the forestry sector, which is especially characterized by a number of non-market outputs. However, we can find also other specific indicators that are relevant to forest management. The paper proposes indicators for sustainability reporting, which are not part of usual methodologies. These indicators will contribute not only to the formal preparation of sustainability reporting, but so that its benefits would be of significant influence on the development of forest enterprises and the forestry sector using its potential in all areas. |
Review of historical outbreaks of the nun moth with respect to host tree speciesOriginal PaperO. Nakládal, H. BrinkeováJ. For. Sci., 2015, 61(1):18-26 | DOI: 10.17221/94/2014-JFS The nun moth (Lymantria monacha /L./) is a polyphagous pest feeding on coniferous and deciduous trees in Eurasia. This paper, based on a literature review, presents an overview of the nun moth outbreaks in Czech forests from 1784 to 2010 in terms of host tree species. At least 22 genera of host trees, bushes and herbs were recorded in the Czech Republic. On the other hand 2 genera were evaluated like non-hosts and 4 genera like indifferent. The nun moth defoliated mainly coniferous forests (almost 90 % of all recorded outbreaks with known data about host trees) in the Czech Republic. Forests with mixture of coniferous and deciduous trees were defoliated nine times less frequent, and only insignificant portion were recorded in clearly deciduous forests. Although wide host range, the nun moth has defoliated predominantly spruce forests (almost 70 %). Mixed coniferous (with mixture of spruce, pine, larch, fir) forests were attacked three times less frequently then the spruce forests. Pine and larch forests were defoliated in low range. Defoliations were sorted also according the intensity. Spatial distribution of the recorded outbreaks was displayed in maps. |
Effect of repeated fertilization on stem growth in old stands of Pinus sylvestris in South East NorwayOriginal PaperO. Haveraaen, L.H. FrivoldJ. For. Sci., 2015, 61(2):72-79 | DOI: 10.17221/110/2014-JFS We studied effects of repeated applications of nitrogen on stem growth of mature Scots pine at four sites with yield potential around 3 - 4.5 m3 ha‑1 yr‑1. Treatments included control (0) and fertilization with ammonium nitrate at 100 and 200 kg N ha‑1. Some plots were supplied with corresponding doses of urea. Applications were repeated up to five times, at five to twenty years intervals. Plot size was 22 x 22 m with buffer zones of 4 m. Measurements were made on an inner plot, 14 x 14 m. Tree ring widths usually reached a maximum two to four years after fertilization, returning to about the original level after seven to ten years. Responses were larger to 200 than to 100 kg N ha‑1. Annual volume increment over the experimental period was 1.5 to 2.0 m3 ha-1 larger in plots provided with 200 kg N ha-1 than in control plots, or even more as the buffer zones of 4 m did not completely exclude tree roots from growing into neighbouring plots. |
Impact of soil conditioners on the growth of European ash (Fraxinus excelsiorL.) on dumpsP. BulířJ. For. Sci., 2005, 51(9):392-402 | DOI: 10.17221/4574-JFS The effects of soil conditioners TerraCottem, Frisol, Bio-algeen and fertilisers Silvamix Forte and Cererit on the survival rate and growth of European ash seedlings until the stage called established plantation were observed on two experimental plots with different anthropogenic substrates. Eight-year experiments showed that under the given conditions the tested agents fulfilled the declared effects only partially. The application of TerraCottem was statistically insignificant both in the survival rate and in the growth. In the applied dose, Frisol manifested itself as an agent that may cause problems with the survival of plants, but at the same time also as a preparation improving the overall growth of young plants statistically significantly. Its effective dosage largely depends on the soil character. Bio-algeen had a very good effect on the survival rate of plants, but it did not surpass the control plants in the initial growth of plants. Silvamix Forte did not cause the mortality of seedlings and influenced the growth of plants statistically significantly for 1-3 years. In the applied dose, Cererit caused a high mortality of seedlings. The application of soil conditioners and Silvamix Forte did not markedly accelerate the growth and development until the stage of the established plantation. Until that time, the costs of the application of conditioners were higher by 4-13% as compared with the costs in the control plants. |
Evaluation of John Deere 1490D operation phase in typical conditions of the Czech RepublicS. Liška, R. Klvač, A. SkoupýJ. For. Sci., 2011, 57(9):394-400 | DOI: 10.17221/21/2010-JFS The life cycle operation phase of John Deere 1490D energy wood harvester from the aspect of energy audit and environmentally negative influence caused by emissions were evaluated. Energy audit quantifies energy used in the form of fuels and oils as well as energy expended for manufacture, transport and distribution of these fuels and oils. Emissions produced by operation are determined according to the consumption of fuels and oils based on emission factors. We also made a comparison of the general calculation of costs based on data provided by the manufacturer with costs ascertained in real operating conditions. The costs are divided into purchase, operating and other costs. Total costs are subsequently converted into unit costs according to the assumed productivity of the machine, its estimated lifetime, and the mean real throughput of the machine. The machine throughput, and thus also its operating economics, is greatly dependent on the character of the processed material, its stem volume, moisture, way of dendromass preparation, and operator's skills. Energy use was calculated at 74.4 MJ.FU-1 (functional unit) related to fuel consumption and 13.4 MJ.FU-1 related to the consumption of oils. The total energy use of the life cycle operation phase of the slash bundler was determined as 87.8 MJ per each bundle produced. The real productivity of the machine in the given operating conditions was several times lower than the productivity indicated by the manufacturer. |
Modelling of tree diameter growth using growth functions parameterised by least squares and Bayesian methodsR. Sedmák, L. ScheerJ. For. Sci., 2012, 58(6):245-252 | DOI: 10.17221/66/2011-JFS The purpose of this paper is to present a new growth and yield function (denoted as KM-function), which was empirically derived from the cumulative density function of the Kumaraswamy probability distribution. KM-function is theoretically well disposed for the prediction of future growth; however, the function also has other theoretical features that make it useful also for retrospective estimation of the past growth frequently used in biological analyses of growth in the initial life stages. In order to demonstrate the practical applicability of the KM-function for growth reconstruction, an investigation of the accuracy of five-year retrospective projections of the real tree diameters obtained by stem analyses of 35 beech trees was done. Bias and accuracy of the new function were compared with bias and accuracy of some well-known growth functions on the same database. Compared functions were parameterised in two ways: by the method of nonlinear least squares and Bayesian methods. Empirical validation of the KM-function confirmed its good theoretical properties when it was used for retrospective estimation of the tree diameter growth. The valuable knowledge of this research is also a finding that the incorporation of a great deal of a priori known facts about the growth of trees and stands in natural conditions of Slovakia into Bayesian parameter estimation led to a decrease in the bias and magnitude of reconstruction errors. |
List of reviewers - 2013List of reviewerseditorsJ. For. Sci., 2014, 60(1):I | DOI: 10.17221/7223-JFS |
Management of mountain forests in the hydrology of a landscape, the Czech RepublicReviewF. Šach, V. Švihla, V. Černohous, P. KantorJ. For. Sci., 2014, 60(1):42-50 | DOI: 10.17221/73/2013-JFS Forests important from a water-management perspective cover 723,000 ha of the Czech Republic (CR), i.e. 27.6% of the forest area. These forests play an important role especially in a mountain landscape. Forests decrease peak flood flows, compensate water discharge and represent a source of high-quality fresh water. The optimum hydrological function is provided by forests that are healthy, ecologically stable, diversified, proper to site, growing on a good forest soil, managed by small-area felling and emulating natural processes. For mountain sites of the CR, the optimum proportion of Norway spruce (+ Silver fir) ranges from 70 to 80% and of European beech from 20 to 30%. Clear-cuts due to air pollution disasters led to replacement of the forest stand by perennial grassland increasing stormflows and decreasing the soil water supply to groundwater resources and the quality of water discharged from the forest. Skidding and hauling operations and an improperly constructed and maintained road network increased the surface runoff from a forest. Intraskeletal erosion occurs on pollution-disaster stone fields and in dying forest stands on stony sites. Reforestation of stone fields is necessary for the preservation of forests on stony and bouldery localities and their services for the cultural landscape situated below. In mountain headwaters, torrent control and forest amelioration are of great importance. These decrease peak flood flows, compensate water discharge and reduce bed-load and sediment transport. Forest amelioration enables the reforestation of waterlogged pollution-disaster areas. |
Operation times in John Deere 1110 E forwarders in regeneration fellingOriginal PaperA. Kabeš, J. Dvořák, P. NatovJ. For. Sci., 2014, 60(6):248-253 | DOI: 10.17221/53/2014-JFS We calculated high-power forwarder productivity in regeneration felling with the objective to set long-term work plans. Based on the time studies of the forwarder operator's work operation the operation time consumption was calculated and operation standards for the studied type of forwarder were designed. The standard values were determined based on the volume weight of harvested timber and the forwarding distance. The resulting time consumption required for forwarding 1 m3 of timber, whose mean tree volume is 0.30-0.99 m3.stem-1, and upon forwarding distance of 100-1,000 m ranges from 0.05-0.09 Nh.m-3. |
Visible foliar injury as a tool for the assessment of surface ozone impact on native vegetation: a case study from the Jizerské hory MtsL. Matoušková, R. Novotný, I. Hůnová, V. BuriánekJ. For. Sci., 2010, 56(4):177-182 | DOI: 10.17221/61/2009-JFS Surface ozone is considered to be a very phytotoxic gaseous air pollutant. Its negative impacts at both the cell and the organ level have been shown, mainly as a result of experiments. However, the demonstration of ozone negative impacts on native plants is not explicit. An assessment of ozone impact on vegetation and ecosystems using indicators based on ambient ozone concentrations is insufficient and assessment techniques based on internal ozone dose and on real plant damage are more appropriate. Such a possible technique is the mapping of ozone visible symptoms due to ozone influence. The ICP-Forest method concerning ozone visible symptoms and the assessment of ozone influence were applied for the purposes of this case study. The visible symptoms are characterized by a few typical signs. Nevertheless, the identification of visible symptoms in native conditions can be problematic and misleading conclusions could be drawn. Therefore it is necessary to complete the identification of visible symptoms with a validation in order to confirm ozone as the cause of plant injury. |
Analysis of price changes of selected roundwood assortments in some Central Europe countriesJ. Suchomel, M. Gejdoš, L. Ambrušová, R. ŠulekJ. For. Sci., 2012, 58(11):483-491 | DOI: 10.17221/98/2011-JFS The paper deals with the analysis of price changes of roundwood (spruce, fir and beech sawlog, fuelwood) and energy wood in Slovakia, Czech Republic and Austria during the period of 2008-+September 2011. At the beginning of the article, the authors identify the major factors influencing timber price trends such as legislation regarding technical standards for the quality grading of round wood, global economic recession, incidental felling and political influence. Consequently, detailed analysis of timber price changes in selected European counties is provided by means of line graphs. The results of the analysis revealed that demand for wood and wood products began to decrease in mid-2008. The most critical situation was in 2009, primarily in the softwood market, when prices bottomed out. However, recent trends indicate a gradual rise in timber prices. In the future, a slight increase of timber prices is expected, however other factors (such as economic development, lobbyist pressure, incidental felling and many others) may influence prices, which makes it difficult to predict their trend. |
Rural development policy in the context of actor-centred institutionalismOriginal PaperZ. Dobšinská, J. Šálka, Z. Sarvašová, J. LáskováJ. For. Sci., 2013, 59(1):34-40 | DOI: 10.17221/24/2012-JFS We analysed the formulation of Rural Development Programme of the Slovak Republic for 2007-2013 applying the theory of actor-centred institutionalism and its interaction forms. Approaches accentuating the role of actors and their interactions are an appropriate tool for the better understanding of cross-sectoral relationships and the improvement of public policy coherence in the formulation process of strategic documents in rural development. Methodologically the study is based on a qualitative analysis of documents and standardized interviews. The formulation of RDP SR 2007-2013 is showing signs of cross-sectoral coordination between different actors in the form of bargaining, as well as signs of hierarchical coordination among public and private actors. In the formulation process of RDP SR 2007-2013 a negative mechanism of coordination was dominant with negative consequences for the policy coherence of the final document. A positive element for the coherence of rural development policy is the observation of decision-making elements in networks. |
Recent results of Czech-American fir hybridization researchOriginal PaperJ. Kobliha, J. Stejskal, P. Škorpík, J. FramptonJ. For. Sci., 2013, 59(2):64-71 | DOI: 10.17221/55/2012-JFS Fraser fir (Abies fraseri) Christmas tree plantations in North Carolina are infested by root rot caused by Phytophthora cinnamomi. This disease kills almost 100% of Fraser fir material and leaves the soil permanently infested. Control crossings of Mediterranean fir hybrids Abies cilicica × Abies cephalonica with Abies fraseri were performed to ensure possibly resistant hybrid material of desired Christmas tree parameters. Pollen of various clones of A. fraseri was shipped to the Czech Republic by NCSU. Control pollinations were performed in April/May 2010 and 2011 in our hybridization seed orchards. Female strobili were isolated in the period of their highest receptibility. Cones were collected during September. Cones were dried and completely disintegrated. Basic parameters of cones and seeds were assessed for each seed lot. Seed samples of the individual seed lots were X-rayed for assessment of the final share of full seeds. In 2010, the most successful combination CZ2 × NC81 brought 7% of viable seeds. In 2011 the most successful combination was CZ2 × NC26 with 18% of viable seeds. |
Study of briquette properties at their long-time storageOriginal PaperM. BrožekJ. For. Sci., 2013, 59(3):101-106 | DOI: 10.17221/27/2012-JFS The paper presents the results of laboratory tests aimed at the study of storage place, storage manner and storage time in relation to mechanical properties of briquettes made from spruce shavings. A BrikStar 50 briquetting press with a pressure chamber 65 mm in diameter of the Briklis firm was used for the briquette production. All briquettes were made at the constant adjustment of all parameters of the briquetting press. The briquette properties were evaluated by determination of their density and rupture force. Moreover, mechanical durability, gross calorific value, total moisture and ash content were determined. It follows from the results of tests that at briquette storage in a well closed plastic bag neither place nor storage time influenced significantly their life time. At briquette storage in a net plastic bag various intensive damage to briquettes occurred, mainly depending on their storage place and storage time. |
Forest visitors' opinion of recreational facilities and trails in forests in the Blaník Protected Landscape Area - a case studyOriginal PaperA. Drábková, L. ŠišákJ. For. Sci., 2013, 59(5):185-190 | DOI: 10.17221/77/2012-JFS Currently, recreation is the most common use of protected areas and there are scarce data on the users and their opinion. The research was focused on visitors to the Blaník Protected Landscape Area (hereafter referred to as PLA), a well-known recreational area where data on visitors, important for PLA management, are missing. Therefore, the aim of the paper is find out: what kind of visitors comes to the study area; the type of forest trails and tourist facilities the visitors prefer. A questionnaire survey of forest visitors was used. Results show that the visitors mostly prefer maintained trails. According to forest visitors' opinion, the most convenient facility to place near the forest tourist trail is the nature trail panels. Furthermore, based on the acquired data, it was possible to create a visitor's profile which is important for respective research and other case studies in similar areas, and for managers of protected landscape areas to comply with both the visitors' needs and the needs of the protected area. |
Foliar nutrient status of a natural fir forest in GreeceOriginal PaperP. MichopoulosJ. For. Sci., 2013, 59(5):191-195 | DOI: 10.17221/11/2013-JFS The foliar nutrient status was examined in a degraded Greek fir (Abies cephalonica Loud.) forest in Mount Parnitha near Athens, Greece. The examination lied in comparing the foliar concentrations of Ca, Mg, K, N, P, Fe, Mn, Zn and Cu with the critical values referring to conifers and the elemental percentages with regard to N of the forest with the corresponding percentages of a healthy Bulgarian fir (Abies borisii regis) stand, the closest relative of the Greek fir. It was found that the needles of the Greek fir had significantly lower concentrations from the N and P critical values. Significant differences were found for the Ca/N, Mg/N, P/N, Fe/N and Mn/N percentages. Significant correlations for the Greek fir were found between needle weight and foliar N as well as between needle weight and the percentages Ca/N and Fe/N. It is highly probable that N and P in the Greek fir are in short supply. |
Felling and skidding damage to residual trees following selection cutting in Caspian forests of IranOriginal PaperF. Tavankar, B. Majnounian, A.E. BonyadJ. For. Sci., 2013, 59(5):196-203 | DOI: 10.17221/53/2012-JFS The felling and skidding damage to residual trees was investigated in a selectively cutting operation in the Caspian forest of Iran. The logging operation was performed by chainsaw and cable skidder. Prelogging, after felling and skidding operations residual tree injuries (species, DBH and damage) were inventoried by systematic plot sampling. Two types of tree damage were observed: destroyed and injured. In this study felling operations mainly injured trees whereas skidding was the main cause of destruction. The percentage of destroyed and injured residual trees by felling operations was 1.4% and 3.4%, whereas the percentage of destroyed and injured residual trees by skidding operations was 5.2% and 11.1%. About 87% of destroyed trees were found in the DBH class smaller than 22.5 cm. Maple and Alder were the most damaged trees among the other trees species. Damage to the lower bole and wood damaged intensity were the most common type of injury. To reduce the stand damage, skid trails should be planned before felling and felling directions should be predetermined. In the selection cutting management, limiting logging damage to residual trees must therefore remain a major objective. |
The proportion of heartwood in conifer (Pinus sylvestris L., Picea abies [L.] H. Karst.) trunks and its influence on trunk wood moisture -Original PaperM. MillersJ. For. Sci., 2013, 59(8):295-300 | DOI: 10.17221/29/2013-JFS As the tree age increases, the formation of heartwood takes place in the central part of the tree. Since there is a large difference in the moisture content between sapwood and heartwood in conifers, the proportion of heartwood expressed in percentage is one of the most important factors influencing the average moisture of trunk wood. The aim of the research was to find out the changes in parameters of heartwood proportion and the changes in average trunk wood moisture parameters, depending on the age of the tree. To evaluate and compare the heartwood proportion in pine and spruce trunk and its moisture, sample plots were established throughout the territory of Latvia in 2011. These sample plots were established in stands of different ages (37-143 years). The total number of sample plots was 61-29 for pines with 246 sample trees and 32 sample plots for spruces with 270 sample trees. With the increase in the tree age from 60 to 140 years, the heartwood proportion increases and the average moisture content of trunk wood decreases. With an increase of the heartwood proportion in pine from 18% to 39%, the average moisture of trunk wood decreases from 108% to 86%, but with an increase of the heartwood proportion in spruce from 30% to 49%, the average moisture content of trunk wood decreases from 107% to 81%. |
Free European data on forest distribution: overview and evaluationOriginal PaperJ. Trombik, T. HlásnyJ. For. Sci., 2013, 59(11):447-457 | DOI: 10.17221/58/2013-JFS A growing need for the evaluation of prospects and sustainability of forest resources calls for the availability of harmonized data on forest distribution. We described and evaluated nine datasets providing such information: Corine LandCover, four European forest maps and four tree species distribution maps. Apart from providing a condensed overview of these datasets, we focused on the match between selected forest maps and forest management plans (FMPs) of Slovakia, which can be thought of as highly accurate information on forest distribution. The degree of match between forest and species area, within 306 forest administrative districts of Slovakia, was used as an indicator of accuracy. In addition, the match between the total forest and species area in Slovakia, given by FMPs and by evaluated datasets, was addressed. We found a high degree of match for the datasets on forest distribution (R-square 0.77-0.93, depending on the dataset), as well as strong agreement in total forest area (± 5%). Both indicators are worse in the case of forest type evaluation (coniferous and broadleaved). Poor results were obtained for tree species maps, which under- or overestimated species areas by tens of per cent, although differences were highly variable among species. The obtained results are valid mainly for temperate forests. |
Road network optimization using heuristic and linear programmingM. R. Ghaffariyan, K. Stampfer, J. sessions, T. Durston, M. Kuehmaier, Ch. KanzianJ. For. Sci., 2010, 56(3):137-145 | DOI: 10.17221/12/2009-JFS To minimize the cost of logging, it is necessary to optimize the road density. The aim of this study was to determine optimal road spacing (ORS) in Northern Austria. The stepwise regression method was used in modelling. The production rate of tower yarder was 10.4 m3/PSHo (Productive system hours) and cost of 19.71 €.m-3. ORS was studied by calculating road construction cost, installation cost and yarding cost per m3 for different road spacing. The minimum total cost occurred at 39.15 €.m-3 and ORS would be 474 m assuming uphill and downhill yarding. The optimal road density and yarding distance are 21.1 m.ha-1 and 90 m, respectively. A sample logging area was used to plan different roads and, using network analysis, the best solution was found based on a modified shortest path algorithm. The network analysis results were very different from the optimal road spacing results that assumed roads and logging corridors could be located anywhere in the planning area at a constant cost. Mixed integer programming was also used to get a real optimal solution. |
Forest visitors' opinions on the importance of forest operations, forest functions and sourcesof their financingL. ŠišákJ. For. Sci., 2011, 57(6):266-270 | DOI: 10.17221/135/2010-JFS The survey was conducted in three selected areas of the Czech Republic in 2008, with the results processed in 2009. Forests visitors received inquiry forms (face to face interviews, random sample). The total number of visitors on 8 survey days was 7,369. The total number of filled-in questionnaires in the three areas was 1,122. Tree planting and tree protection are considered as the most important forest operations, followed by road and stream bank maintenance. On the contrary, timber transport and harvesting are considered as the least important activities. The nature-protecting function is considered as the most important forest function, followed by soil-conservation, climatic, hydrological and health (recreational) functions. Timber production and non-timber production are the least important functions according to the respondents. 20% of respondents claimed that increased costs needed to improve non-market forest functions, used by the visitors, should be partially or fully financed from the timber sales revenues, while only 6.5% of respondents say the costs should be partially or fully financed from payments by the users of forest functions. |
Productivity and cost of farm tractor skiddingN. Gilanipoor, A. Najafi, S.M. Heshmat AlvaezinJ. For. Sci., 2012, 58(1):21-26 | DOI: 10.17221/4804-JFS In this study, productivity rate and operation cost of farm tractor were evaluated in a mountainous natural forest. Data for the study came from a detailed time study in the Research and Educational Forest of Tarbiat Modares University (REFTMU) and was used to develop a multiple linear regression model to predict the skidding cycle time. The results showed that effective independent variables of skidding time were skidding distance and slope of skid trail (P = 0.01). Average productivity rate ranged from 2.43 to 2.60 m2.h-1. Total time and effective time, respectively. Total cost of the system was 10.24 USD.h-1 whereas 4.58% of the cost of skidding resulted from personal delay. The cost and productivity resulting from this study emphasized the importance for foresters to consider a farm tractor when designing skidding operations in young stands or prescribing a combination of two machines in mature stands. |
Legal framework for payments for forest ecosystem services in the Czech RepublicK. Ventrubová, P. DvořákJ. For. Sci., 2012, 58(3):131-136 | DOI: 10.17221/71/2011-JFS Although examples of payments for ecosystem services (PES) can be traced back at least as far as the 1980's, it is still a relatively new instrument, and the hitherto experience in many parts of the world is not extensive yet, or based on a very long timeframe. In addition, PES is being introduced in more and more sectors (agriculture, water supply, carbon sequestration, biodiversity conservation, etc.) and in relation to more and more ecosystems (surface water, groundwater, forest, etc.). But such PES can work only with good governance in place, comprising an effective political, legislative as well as institutional system. Nevertheless, an effective introduction of PES system into national legislation calls for an appropriate analysis of the current legal system so that duplications can be excluded and only valuable measures can be added. The main goal of this paper is to analyze if the current legal framework of the Czech Republic provides an appropriate basis for establishing payments for a forest ecosystem services scheme. |
Molecular markers: their use in tree improvementR. Mahajan, P. GuptaJ. For. Sci., 2012, 58(3):137-144 | DOI: 10.17221/5579-JFS Earlier breeders used phenotypic selection based on morphological characteristics to improve tree varieties. These selections often take many cycles of breeding and backcrossing in order to place desired characteristics. But today the knowledge has paved the way for a much deeper understanding of the mechanics of cell biology and the hereditary process itself. Breeders are presented with numerous possibilities of altering the behaviour of existing varieties. Linkage between molecular markers can be translated to genetic linkage maps, which have become an important tool in plant genetics. They may choose to use marker-assisted approaches in order to facilitate the selection of favourable combinations of genes that occur naturally within a tree species. |
Calculus of variations and its application to division of forest landM. MatějíkJ. For. Sci., 2004, 50(9):439-446 | DOI: 10.17221/4639-JFS The paper deals with an application of the least squares method (LSM) for the purposes of division and evaluation of land. This method can be used in all cases with redundant number of measurements, in this case of segments of plots. From the mathematical aspect, the minimisation condition of the LSM is a standardised condition ∑ pvv = min., minimising the Euclidean norm ||v||E of an n-dimensional vector of residues of plot segments at simultaneous satisfaction of the given conditions. The traditional procedure of calculus of variations with the use of Lagrangian function is shown. If some additional conditions are included in the calculation, on the basis of the criteria presented in this article it is possible to evaluate the degree of deformation of the selected solution in relation to the measured quantities. The application of the method of adjustment of condition measurements may help solve the problems of parcel division on the basis of intersection of the parcel layers according to the real-estate cadastre and according to previous land records, valuation, typological, price and other map sources. |
Aboveground biomass of substitute tree species stand with respect to thinning - European larch (Larix decidua Mill.)J. Novák, M. Slodičák, D. DušekJ. For. Sci., 2011, 57(1):8-15 | DOI: 10.17221/24/2010-JFS This study is focused on substitute European larch stands in the Krušné hory Mts. (northern part of the Czech Republic). Research was conducted within larch thinning experiment Kalek (780 m a.s.l. in the category Piceeto-Fagetum oligo-mesotrophicum - Calamagrostis villosa). Results showed that the aboveground biomass of the investigated substitute unthinned larch stand represented approximately 102 thousand kg of dry matter per ha at the age of 20 years. Stemwood (ca 59%) is the most important part of the aboveground biomass. Needles, live and dead branches accounted approximately for 6%, 17% and 11%, respectively, and stem bark only for 7%. At the age of20 years, the investigated substitute unthinned larch stand accumulated: nitrogen - 307 kg, phosphorus - 21 kg, potassium - 136 kg, calcium - 122 kg, magnesium - 53 kg per hectare. Thinning with consequent removal of aboveground biomass may result in nutrient losses. Especially, the removal of whole tree biomass by thinning for chipping in areas previously degraded by acid deposition may result in calcium and magnesium deficiency because of their low content in forest soil. On the other hand, thinning supported faster growth of trees left after thinning and consequently faster biomass and nutrient accumulation. Our results supported the recommendation that the use of biomass from thinning for chipping should be limited to stemwood only and the remaining aboveground biomass (mainly needles and branches) should be left in the forest ecosystem for decomposition in conditions of the historically disturbed area of the Krušné hory Mts. |
Long-term silvicultural experiment with transformation of the mixed stand structureL. Šimerda, J. SoučekJ. For. Sci., 2011, 57(6):259-265 | DOI: 10.17221/2/2011-JFS The paper summarizes the main characteristics of a mixed stand during 80-year transformation to the mixed stand with permanent selective structure. The initial main stand was mostly composed of conifers with group arrangement, broadleaves as the reserved trees created the upper storey. Partial opening by thinnings prepared the stand for regeneration. Heavy thinning in 1959 (22% of the growing stock) opened the main stand and released the advance growth of broadleaves. Subsequent stand development was negatively affected by air pollution. Mainly fir and spruce responded to air pollution by deteriorated health condition and increment reduction. Beech and other broadleaves gradually increased their proportion in the stand (64% of the growing stock in 2008). Initial diameter distribution was sinistral, reserved trees affected the frequency of thick trees. Final diameter distribution resembled the model curve for selective forests, the number of thin trees was below the model curve for broadleaved forests with selective structure in these types of localities. Mean increments of individual species changed according to their stand position. Low fecundity of trees, weed infestation and game damage limited natural regeneration, artificial regeneration dominated for the whole time. The complicated structure corresponding to selective forest occurred rarely during the monitored period, the stand was differentiated mainly by spatial arrangement. |
Broadleaved regeneration dynamics in the Pine plantationK.K. Islam, S. Patricia, Y. RinchenJ. For. Sci., 2011, 57(10):432-438 | DOI: 10.17221/78/2010-JFS In an Island of the Netherlands, Pine (Pinus nigra) was planted to stabilize the dunes and to protect the arable lands from the blowing sand. This research was conducted to understand the most important environmental factors responsible for a vegetation change in the Pine plantation and effect of this change on the rare orchid population: Goodyera repens and Listera cordata. Vegetation sampling was carried out according to the Braun-Blanquet phytosociologic method within the three sites of this Island. Twinspan analysis confirmed the definition of three site types and redundancy analysis showed a significant difference between the pure Pine stands and the plots with regeneration. The results revealed that the most significant explanatory variables were litter cover, broadleaved tree cover, and shrub cover indicating the vegetation change under the Pine plantation. The abundance of Goodyera repens is strongly associated with the Pine forest and negatively related to broadleaved cover. Listera cordata could apparently cope with vegetation change. Controlling the herbaceous layer in the Pine plantation can promote the orchid population but on the contrary, promoting the natural regeneration of broadleaved species might endanger them. |
Findings regarding ectotrophic stability of Norway spruce forest of the Krkonoše and Orlické Mountains based on mycorrhiza studiesV. Pešková, J. Landa, F. SoukupJ. For. Sci., 2011, 57(11):500-513 | DOI: 10.17221/139/2010-JFS Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkonoše and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkonoše Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkonoše Mts. implies that the macromycete species composition developed quite differently but with a similar success. |
