Slovak Forests Research Articles

Assessing the influence of ruminating ungulates on forest regeneration and young stands in Slovakia: results from the National Forest Inventory

Abstract Our analyses utilized data from the latest National Forest Inventory conducted in Slovak forests in 2015–2016. Specifically, we included data on approximately 21,737 trees grown on forest land and 3,342 trees on non-forest land, all with a height of up to 1.3 meters. Browsing emerged as the second most frequent limiting factor for regeneration on forest land, following light deficiency, whereas on non-forest land, it ranked third after ground vegetation and light deficiency. Our results revealed the highest browsing rates on goat willow (47.8%), silver fir (39.3%), and rowan (35.1%). Conversely, certain commercial tree species exhibited relatively low browsing rates, notably Norway spruce (13.9%), European beech (8.1%), and oaks (6.2%). Among abiotic factors, exposition and slope were found to be significant, the south aspect was associated with the highest browsing rates, while browsing rates decreased with increasing slope steepness. Planted trees were more frequently browsed than those of natural origin. At the same time, higher trees (height between 0.5 m and 1.3 m) were browsed more frequently than small trees (under 0.5 m). Furthermore, significant differences in browsing frequency were observed among specific territories (hunting sub-regions), with the heaviest browsing occurring in the southwestern and northeastern parts of Slovakia, as well as in the Rimavská Sobota district. Given that reducing browsing pressure primarily relies on hunting activities, which are outside the forestry sector, close collaboration between foresters and hunters is essential. Additionally, hunting strategies in the near future must consider also the needs of other sectors such as forestry, agriculture, and nature conservation.

Identification of drought-induced forest damage in 2022 and of its key site condition drivers through satellite imagery

Abstract An extensive discoloration (yellowing, browning), and defoliation (leaf loss) were observed in Slovak forests during the summer of 2022. These phenomena are attributed to the combination of very low atmospheric precipitation and extremely high air temperatures from June to early August. In this study, the deterioration of forest health was analysed by comparing the image classification of Sentinel-2 satellite data from the year of intense drought occur-rence, 2022, with that from a referenced year without drought occurrence, 2020. The results indicated that in 2022, the proportion of heavily damaged stands with defoliation exceeding 50% doubled, reaching 19.3% (417,000 ha), and an area of 223,000 ha experienced an increase in defoliation by 30% or more. The damage exhibited an uneven spatial distribution, with the most significant impact observed in the western and southern parts of central Slovakia, as well as partially in the southern part of eastern Slovakia. Further GIS analyses revealed that forests growing on slopes with southern aspects suffered more severe damage than with northern exposures. However, the difference between the most damaged forests with south-southeast exposure (12.2%) and the least damaged ones with north-northwest exposure (8.2%) was only 4%. The level of damage gradually decreased with increasing altitude. Nevertheless, compared to previous studies, the damage was significantly manifested even in the fourth forest vegetation zone, up to an elevation of approximately 800 m. Regarding soil texture, which influences the water regime, the damage gradually decreased with decreasing sand content, ranging from sandy soils (17.5%) to clayey soils (6.6%).

Iron ax-adz from Mytulyn (Lviv region): evidence of migration or unknown type of weapons

The article is devoted to the introduction into scientific circulation of a recent discovery – an atypical iron adz-ax from the Slovak forest near the village Mytulyn. The circumstances and place of discovery of the Mytulyn adz-ax are analysed, its connection with the settlement of the X–XI centuries is proved. In connection with this find, various types of adz-ax of the Middle Ages are studied against the background of places of finds in the cultural layer of settlements and in the early medieval hoards of iron tools from the territory of Ukraine. The conclusion about the local peculiarities of the species composition of the hoards of iron tools is substantiated. The uniqueness of the Mytulyn type of long axes for the territory of Ukraine has been clarified. Possible parallels with the findings of adz-ax of this type of tools in different regions of Eastern Europe can be traced. Unlike ordinary adz-ax, the Mytulyn find was a more specialized tool, possibly for carving single-decker boats. Such long axe-like iron bar with a rectangular cross-section and a narrow blade were common among the Western Slavs (Greater Moravia, Poland). In this regard, the possibility of the West Slavic genesis of this type of ax is considered. The closest analogy of adz-ax from Mytulyn is long curved narrow-bladed axes, which are found only in military burials in one region of the Western Volga region - the basin of the Tesha and Moksha rivers, where 32 long axes are known today. All of them are of the same type and most of them come from the Mordovian burials of the XI–XIV centuries. However, no adz-ax has been found among these axes yet. Since the druzhyna of the great Kyiv princes often involved units from outside Kyiv, the conclusion is substantiated that a long adz-ax appeared in Halychyna in connection with the campaigns of Kyiv princes against the Galicians near the turn of the XI–XII centuries. Key words: archaeological finds, iron tools, princely era, adz-ax, Mytulyn.

The Slovak forest policy arrangement: Post-1989 residues and changes

After 1989, Central and Eastern European countries with planned economies launched a process of transformation. In the Slovak forest policy, the main changes have been in the structure of forest ownership, increasing the share of governance mechanisms within the decision-making, and the organization of the sector. The aim of the paper is to analyse the current Slovak forest policy arrangement in relation to the socialistic political history, via the Policy Arrangement Approach. The analysis is based on literature search and consultations with forest policy experts. In total, 55 scientific publications were analysed. Subsequently, the results were consulted with four national forest policy experts. Despite the three decades-lasting transformation process, in Slovakia, forest policy is characterised by a strong influence of governmental actors, centralisation, and prevailing hierarchical use of policy instruments. Nature protection actors enter the policy arena, for instance, to expand protected areas. The top-down planning has an impact on the forest owners’ performance of rights to use their forests. Non-governmental actors attempt to enforce their interests through participation mechanisms, inter-ministerial commenting procedures, and voluntary instruments. Public opinion is turning towards nature protection and forestry as such has come under pressure with its traditionalist approach.

Occurrence of gypsy moth (Lymantria dispar L.) in the Slovak Republic and its outbreaks during 1945–2020

Abstract The gypsy moth is one of the most serious pests in forests and fruit tree plantations over prevailing parts of the Northern Hemisphere. This work is based on a literature review, and presents history of gypsy moth Lymantria dispar L., observed in Slovak forests within the period 1945–2020. The life cycle, hosts, natural enemies, population dynamics of pests, impact of outbreaks on forests and different management methods used in the past are discussed. Since 1945, there were nine gypsy moth outbreaks in Slovakia. Between 1945 and 2020, a total of 155,034 ha of deciduous forests were touched with varying intensity, representing an average annual damage of 2,040 ha. The strongest outbreak culminated in 2004. Totally 51,479 ha were attacked in the period of 2000–2008. We have found outbreak periods that repeat with frequency of 7.8 ±2.2 years and the average outbreak phase lasts 3.1 ±1.1 years. The period between two subsequent outbreaks seems to be more or less constant and duration of the outbreak phase seems to be gradually shortened during the study period. Several factors influencing the gypsy moth population dynamics in Slovakia are discussed. The role of biological control by using entomopathogenic fungus Entomophaga maimaiga is described.

Economic Efficiency of Forest Enterprises—Empirical Study Based on Data Envelopment Analysis

Countries are forced to develop bio-based economic strategies to promote efficient use of renewable natural resources. The transition towards a sustainable forest bio-based economy is associated with resource efficiency optimization, adoption of innovative bio-based approaches in terms of technological improvements and cost effectiveness, and an opportunity to reach multiple societal challenges. This paper is focused on a comparative analysis of the forestry sector in the Republic of Bulgaria and the Slovak Republic by estimating the economic efficiency of four Bulgarian state-owned forest enterprises and four Slovak forest enterprises. The evaluation of economic efficiency was carried out using selected indicators of the studied enterprises over a period of five years. A data envelopment analysis (DEA) approach was used as a non-parametric linear technique for measuring the relative efficiency of a set of production decision-making units (DMUs). The Malmquist productivity index (MPI) was used to assess the pure efficiency changes (PEC) and technological changes (TCs) of the studied forest enterprises. Data for 2014–2018 were processed. The results obtained for the economic efficiency study outlined the major factors affecting the differences in efficiency scores. The long-term sustainability and increased economic efficiency of forest enterprises in both countries can be achieved by improvements in forest management and investments in research and development activities.

Circular economy versus planetary limits: a Slovak forestry sector case study

PurposeCircular economy is presented as an approach to economic growth that is in line with sustainable development. However, the recent literature has highlighted the limits of the concept in terms of environmental sustainability. The study examines the relationship between circular economy and conservation of ecosystems, using a case study on the implications of a circular economy for Slovak forests and forest sector.Design/methodology/approachThis study adopts a qualitative methodology through a focused review of the relevant literature on circular economy and sustainable development and primary data gathered through semi-structured interviews with 15 experts and practitioners in the forest sector, forest conservation and circular economy context, both from within as well as outside of Slovakia.FindingsThe study finds that the forestry sector has an important role to play in a shift to a circular economy in Slovakia, with significant opportunities for improved efficiency as well as substitution of wood for non-renewable resources. There is also growing potential for ecosystem stewardship and restoration. However, the increased application of biomass could crowd out other needs, including for biodiversity. Safeguarding these services depends ultimately on good governance.Originality/valueThe study highlights that circular economy taken in a narrow focus on resource efficiency is insufficient to ensure environmental sustainability but rather needs to be set within the broader environmental and social context.

Carbon sequestration in living biomass of Slovak forests: recent trends and future projection

Abstract The paper predicts development of forests in Slovakia from the perspective of carbon sequestration. Projection is based on actual trends of changes in forest area, age structure and tree species composition of forest stands managed according to forest management plans. Carbon balance in living biomass has been simulated until 2050 under two harvesting scenarios (based on planned and realized harvesting rates in reference period 2014–2019) with four possible combinations of fixed or changing tree species composition and size of forest area. Input data were stratified by tree species and 10-years wide age classes. A model simulating forest growth using yield tables and harvesting rates was developed and applied for prediction. Results indicate that the scenario based on realized harvesting would lead to a higher level of CO2 removals from atmosphere by living biomass in Slovak forests for the whole simulated period, despite their decrease from the current level ~ −4,000 kt CO2 to ~ −2,000 until 2040 and an increase to~ −2,800 kt CO2 in 2050. Conversely, scenario based on planned harvesting could result in a stronger decrease of CO2 removals, with the culmination in 2040 at ~ −200 kt CO2 followed by a slight increase to ~ −1,000 kt CO2 in 2050. The influences of changes in tree species composition and increasing forest area were significantly lower than effect of different harvesting rates. Results achieved by this study suggest that adjusting harvested volume (e.g., by decreasing harvesting rates or modifying rotation periods) could be the most effective tool to intensify CO2 removals by living biomass in Slovak forests in the upcoming decades.

Mapping Cultural Ecosystem Services Enables Better Informed Nature Protection and Landscape Management

Cultural ecosystem services (CES) have specific richness and diversity provision patterns related to particular landscape features and land cover forms. Studies of their spatial distribution, however, are quite rare in the Slovak Republic and surrounding countries. This paper links land cover information based on an ecosystem services (ES) matrix, field survey data and GIS method to assess CES supply in two selected Slovak regions. Our main focus is on the ecologically more valuable ‘hot-spots’ where socio-cultural values accumulate. We determined their spatial distribution, and our comparison with lower cultural value areas confirmed that mountainous landscapes have the highest capacity to provide CES. This especially applies to the landscapes under National Park protection. While Slovak forests, rocks and water areas also form essential ecosystems for overall CES provision, the lowest overall capacity is in areas with residential buildings, construction, industrial and other artificial habitats. Finally, a comparison of our results with the National Ecosystem Assessment indicates that our detailed CES assessment will be more effective in supporting future participatory planning and management processes.

Analysis of workplace injuries in Slovakian state forestry enterprises

Abstract The aim of the paper is to identify the most common workplace accidents regarding injured body parts with respect to anthropometric data measurements of the population in the Slovak republic. Data from workplace accidents database over the years 2000-2017 were drawn from the records of the Slovak Forest state enterprise. The highest number of workplace accidents (31.7% of all recorded workplace accidents) occurred during the forest harvesting phase. Timber skidding with 15.9% of recorded accidents was the second highest risky phase. In four phases Timber harvesting, timber skidding,Works at conversion depot, Repairs and maintenance was 76% from all injuries in forestry state enterprises was occurred. Nonsignificant increase in the injury rate over the years 2000-2017 was determined in the analysis of the injury rate in the Slovak state forests. From the point of view of the longterm changing anthropometric parameters of the adult population, it is also necessary to take into account the ergonomic parameters and the technological procedures of the performed work and the working environment.

Trends in Workplace Injuries in Slovak Forest Enterprises.

The aim of the paper is to analyse the effect of key factors affecting the risk of workplace injuries and to identify the most common workplace accidents regarding injured body parts with respect to anthropometric data measurements of the population. Data associated with workplace accidents over the years 2000–2016 were drawn from the records of the state enterprise Forests of the Slovak Republic, situated in Banská Bystrica. Gathered data were processed and entered into the database complemented by the data on accidents of the self-employed working in the forestry industry. A total of 1874 workplace accidents in the state enterprise were recorded and statistically evaluated during the analysis period. A method for contingency table was used to analyse correlation between qualitative (categorical) variables in the dataset. A Poisson regression model was used to determine the injury rate. Forest harvesting is considered the most risky phase of the process of harvesting, processing, and transport. The highest number of workplace accidents (31.8% of all recorded workplace accidents) occurred during the forest harvesting phase during the analysis period. Timber skidding, with 16% of recorded accidents, was the second highest-risk phase. The workplace injury rate in the forest industry in Slovakia decreased over the course of the years 2000–2016. Head and facial injuries were those with the highest rate (67.1% injuries of these body parts) during the phase of harvesting and skidding.

Innovation Strategy in Slovak Forest Contractor Firms—A SWOT Analysis

The aim of the study is to determine the innovation strategy of contractor firms in the Slovak forestry service sector in the area of further innovation activities development. The strategy identification was based on the analysis of the strengths, weaknesses, opportunities and threats in this sector. The results indicate that weaknesses of contractor firms exceed their strengths and, considering the degree and importance of their impact, opportunities exceed identified threats. Based on these findings revealing the relations in the area of innovation activities of forestry service contractors, the “Strategy of Partnership” was suggested as the most suitable type of strategy. It can be concluded that such a form of grouping cooperation brings many benefits to contractors in the form of information availability, guidance, training, and management of conflicts, risks and uncertainty, which are associated with the innovation process.

Salvage felling in the Slovak forests in the period 2004–2013

Abstract Salvage felling is one of the indicators of the forest health quality and stability. Most of the European Union countries monitor forest harmful agents, which account for salvage felling, in order to see trends or functionality between factors and to be able to predict their development. The systematic evidence of forest harmful agents and volume of salvage felling in Slovakia started at the Forest Research Institute in Zvolen in 1960. The paper focuses on the occurrence of the most relevant harmful agents and volume of salvage felling in the Slovak forests over the last decade. Within the 10 years period (2004–2013) salvage felling in Slovakia reached 42.31 mil. m3 of wood, which was 53.2% of the total felling. Wind and European spruce bark beetle Ips typographus damaged 78.4% of salvage wood, i.e. they were the most important pest agents. Norway spruce (Picea abies) was the most frequently damaged tree species that represented the amount of 35.6 mil. m3 of wood (81.2% of total volume of salvage felling). As Norway spruce grows mostly in mountains, these regions of Central and Northern Slovakia were most affected. At the damaged localities new forests were prevailingly established with regard to suitable ecological conditions for trees, climate change scenarios and if possible, natural regeneration has been preferred. These approaches in forest stand regeneration together with silvicultural and control measures are assumed to gradually decrease the amount of salvage felling over long term perspective.

Value of forest berries and mushrooms picking in Slovakia's forests

Non-wood forest products have important commercial, environmental, social and recreational roles in many European forests. Collecting wild foods from the forests now largely represents a form of recreation. In some countries, any revenues from the sale of wild food are exempted from income tax. The main objective of this work is to estimate the value of the selected forest berries and mushroom picking in Slovak forests. A random sample of 5,168 Slovak inhabitants was surveyed, with 1,534 interviews in 2006, 1,732 interviews in 2007, 1,402 interviews in 2008 and with 500 interviews in 2011. Face to face interviews were used and people were asked to answer prefilled questions. Based on the results of the survey, the most collected forest berry is blueberry (Vaccinium myrtillus), one third of respondents stated, that they picked them either for own consumption or for sale. Harvest activity in mushrooms picking is connected mainly with Boletus sp. They were picked by two-thirds of respondents for own consumption and by 2 % for sale. Mushrooms picking implies revenues of around 110–140 mil € annually. Levels of activity differed in each year. It can be influenced also by poorer crop in some years. In general, average price was higher in years with lower harvest.

Dynamika obnovy a vývoja lesných porastov na Slovensku počas ostatných piatich desaťročí

Abstract General information on forest growth and development as well as different approaches of forest management are presented in the introduction of the paper. Furthermore, it shows an analysis of the development of tree species composition in the Slovak forests during the last 50 years. Historical data base for the analysis originated from the forestry records (especially Permanent Forest Inventory). Our attention was focused on reforestation with respect to tree species, tree species composition in young forest stands by age classes and relations between these forest characteristics. The next section of the paper describes new proposals for regulation of forest regeneration and reforestation with the aim to achieve desired tree species composition in all age classes, not only in accordance with natural conditions but also respecting human demands in the future.

Analýza aktuálneho zvyšovania produkcie Lesov SR na základe údajov LHP

Abstract This paper is based on results from assessment of the production characteristics development in sampling sets of forest management plans with the same date of validity and the validity period. Database is generated by basis sets of forest management plans valid from 1983. The aim of the analysis is to quantify and compare the development of production characteristics of the prevailing tree species in time levels and to quantify the impact of increasing growing stock. We have analysed the variables of the main crop: mean height, mean diameter, absolute yield class, current annual increment, growing stock and crop density. The result is a progressive, balanced and significant trend of increasing production characteristics, which confirms the results of the selection assessment and indicates increased and fast growth of Slovak forests in the research period. The analysis showed that increasing total growing stock is caused except increasing mean heights and mean diameters in particular by changes of the age structure that is reflected in increasing average age of the area.

Damage to spruce stands in the Kysuce and Orava region determined from the National Forest Inventory

An analysis of the status of spruce stands in the Kysuce and Orava region was performed and their health condition was compared to the spruce forest constitution in the rest of Slovakia. For this purpose, the inventory plots established within the first circle of National Forest Inventory (NFI) in 2005 and 2006 were used. The Kysuce and Orava regions significantly differ from the rest of Slovak forests by its high proportion of spruce. The health status of the spruce stands in these regions, according to the salvage felling as a result of the damage caused prevailingly by stem rotting and bark beetles appears worse than in the rest of Slovakia. The analysis showed that not only the acute damage of spruce stands (insects) but also the chronic damage of trees (rotting, mechanical damage during logging) is more serious in these regions than in the rest of Slovakia. The browsing caused by deer game (data does not include young stands) in both regions as well as in the rest of Slovakia seems to be low and not so serious compared to the previously mentioned types of damage. Other sorts of damage (stem breakage, standing dead trees, or damage by insect) have also small proportion. More detailed analyses of NFI data with acceptable precision were possible only for most frequent kinds of damages such as stem rotting and damage by logging. The results showed the frequency of rotting tended to be higher with increasing stand age. Influence of altitude on the frequency of the damage was not evident. Since variability of selected types of damage on spruce forest in the target regions was high, all results are presented with the precision at 68 % confidence interval.

Different approaches to the classification of vertical structure in homogeneous and heterogeneous forests

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.

Acidification of forest soils in Slovakia - causes and consequences

In Slovakia, soil acidification remains an environmental and forestry related issue despite a sharp decrease in the S02. Recent monitoring of critical acid loads of Slovak forests show that around one third of Slovak forests are directly affected by acidification. In this situation, an increased biomass extraction from forests for energy generation purposes, considered by some decision-makers, poses a serious threat to geobiochemical cycles and may further aggravate the effect of the emissions on soils. In other parts of the country however, the drop in pH value means a soil degradation in sense of soil forming processes rather than in reference to forest production. This fact is also confirmed with the values of growing stock in Slovak forests, continually increasing since 1920.

Quantification of anthropogenic lead in Slovak forest and arable soils along a deposition gradient with stable lead isotope ratios

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