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HR  EN   



Scientific-technical and professional journal
of Croatia Forestry Society
                         Issued continously since 1877.
       First issue of this web edition start with number 1-2/2008.
   ISSN No.: 1846-9140              UDC 630*https://doi.org/10.31298/sl

Portal of scientific
journals of Croatia
   Issued by: Croatian Forestry Society

   Address: Trg Mažuranića 11, HR-10000 Zagreb, Croatia
   Phone/fax: ++385 1 4828477
   e-mail: urednistvo@sumari.hr
   Editor in Chief: Josip Margaletić

Uredništvo   293
Civil initiative to engage in collective tree planting on October 25, 26 and 27      
The headline of the editorial was prompted by a civil initiative sweeping through Croatia in recent times. The Facebook group, which calls for “three enjoyable days of planting trees across the State” under the motto “Plant a tree, don’t be a stump”, is imbued with enthusiasm and a wish to raise the awareness of Croatian citizens of the need to preserve and protect the nature; however, there are also more radical views on the forestry profession and the company Croatian Forests Ltd. Among others, they ask why there are no public afforestation activities and conclude that the reason lies in the fact that cutting trees has priority over planting them. There is an undergoing statement: “They cannot fell more than we can plant!” The campaign was prompted by large-scale planting campaigns in some countries such as India and Ethiopia. Another incentive to the campaign was provided by the devastating fires taking place in the lungs of the world, the Amazonian rain forest. The will and wish to plant trees deserves full credit, but we cannot be compared with the countries with different climatic and habitat conditions, in which felling or forest fires result in deforestation, loss of forest soil and inability of forests to regenerate. The situation in the Republic of Croatia is diametrically opposite: reforestation is an ongoing process; in other words, the forest spreads into abandoned agricultural and other areas, so that currently almost half of the country is covered with forests of different age categories. This campaign reflects the concern of the ordinary person, but also contains certain ill founded hysterical reactions targeted at foresters in Croatia.
In view of the ever more frequent and unfounded attacks on the forestry profession, which has gone out of hand, it is time for the profession to voice its opinion. We can do it in two ways: we can either put forward professional and well founded arguments, or retaliate in the same impertinent manner in which we are being attacked. To start with, for those who are ready to listen, let us stress that felling is a silvicultural operation. A forest or a tree has its beginning, followed by growth through different silvicultural stages until it reaches its optimum and finally the stage of “dying”. The task of the forestry profession is to deal with this last stage by cutting down old trees, making profit for the society by processing these cut trees, and ensuring natural regeneration in even-aged stands in the years of good seed mast. Before any negative attitude on a felling operation is taken, it would be advisable to inspect closely the area which was until “yesterday” covered by an old oak forest and check what is being planted in this area, if anything. In a selection forest of, e.g. beech and fir, felling is applied to remove old mature trees and those trees which prevent young trees from reaching the necessary light for growth. Reforestation with seeds or with so-called “trained” seedlings is applied only in those areas in which natural seedling has not been completely successful or in areas badly affected by fires. Maintaining the forest in a perpetually stable condition is the principle of sustainable management. This principle is something that Croatian science and practice is rightly proud of and for which it receives acknowledgement from the global forestry world.
What does the company Croatian Forests Ltd do, some protesters ask? The task of the company, as a state-owned company which has been entrusted by the State with caring for the forests, is to manage forests and carry out all the jobs set down in management plans, in line with the Forest Act,  the forestry policy and strategy. There is no question here of chaotic and disorganized management. Management plans for every management unit prescribe the execution of ten-year activities. These plans are  verified by expert committees and approved by the corresponding minister. They also contain regulations and rules set down by the Ministry of Environmental Protection. As seen from the above, nothing is done on an amateur basis - everything is firmly grounded on scientific and expert knowledge of the forestry practice, which has been acquired through 250 and more years of organized forestry. Climate change, damage caused by ice and wind, as well as pests, to which forests have been particularly exposed in recent times, make work in forestry even more difficult and require even more expertise and knowledge - certainly not amateurism. This is the reason that as far back as the 18th century it was realized that management of forests required not just a college degree but academic education. In Croatia, this was put to practice in1898, when the Forestry Academy (the present day Faculty of Forestry) was opened as the fourth institution of higher education within the University of Zagreb.
A battle against excessive felling should be fought in parts of privately owned forest areas, yet the above groups fail to grapple with this problem. Allow us to be  impertinent enough to ask: who are “they” who are not allowed to perform felling operations? Perhaps those who have studied forestry for five years, acquired knowledge of botany, higher mathematics, chemistry, meteorology, plant anatomy and physiology, pedology, dendrology, dendrometrics, silviculture, ecology, forest planning, forest protection and other fields, and who have, when receiving their degrees of graduate engineers of forestry, pledged to adhere to expert forestry principles in their work?  Such professionals are then lectured by those who have “googled” something about forestry and who have gained their knowledge of forestry at weekend outings in forests. We would welcome with open arms their expert advisors, which they claim there are many, to finally come out and engage in public debates. We would expect from these groups to support us in opposing the move to cut down on non-market forest function fees, which are used to finance the construction of fire breaks, fire suppression, reforestation of burnt areas and demining areas. Obviously, they prefer these fees to be “pushed” into parafiscal levies.  While the Croatian government expects from the company Croatian Forests Ltd to pay into the state budget, the German government invests 500 million euro into the recovery of forests, since over 110,000 ha of forests dried only last year.
We have nothing against making city areas green, but this should be carried out in a planned manner, both as regards the choice of areas and the choice of tree species, taking into account their ecological and biological requirements. Planting anything and anywhere, as seen from the initiative, is irresponsible both for the area and for the plant.
Editorial Board

Joso Vukelić, Irena Šapić, Giacomo Mei, Igor Poljak, Ivana Plišo Vusić, Marko Orešković  UDK 630* 181.6 + 272 (001)
Black alder forests (type 91E0* Natura 2000 type E.2.1.9. NHC) in the Plitvice Lakes National Park      
The paper presents the first results of monitoring Natura 2000 habitat type 91E0*in the Plitvice Lakes National Park (Croatia). This type is represented in black alder forests (Alnus glutinosa /L./ Gaertn.) on an area of 44 ha. There, following the Braun-Blanquet method (1964), 25 plots were set up and relevés made, with 175 species of higher plant species recorded. Their environmental and sociological features suggest wetland and periodically flooded habitats with high ground water levels throughout the year, hence hygrophytes are decisive for the community structure. In addition, there is a moderate share of mesophilic species that are not present in the wetland black alder forests along the Sava and Drava rivers in the lowland part of northern Croatia.
A comparison of black alder forests of the Plitvice Lakes NP with other black alder syntaxa in Croatia (Figure 2, Table 3) demonstrates that, together with other alder stands in the Dinaric region of Croatia, they belong to the group of wetland forests of the alliance Alnion glutinosae. Their differentiating
species with regard to other syntaxa of the alliances Alnion glutinosae and Alnion incanae in Croatia are Fraxinus excelsior, Daphne mezereum, Viburnum lantana, Cirsium oleraceum, Crepis paludosa, Equisetum arvense, Paris quadrifolia, Thalictrum aquilegifolium, Valeriana dioica, Veratrum album, Acer pseudoplatanus, Chaerophyllum hirsutum, Lonicera xylosteum, Filipendula ulmaria, Knautia drymeia, Cruciata glabra. In addition, the researched stands in the Plitvice Lakes NP demonstrate individuality with regard to other stands of the Croatian Dinarides through the differentiating species of Phalaris arundinacea, Dactylorhiza maculata, Cirsium arvense, Primula vulgaris, Listera ovata, Carex acutiformis, C. paniculata, Succisa pratensis, Gentiana asclepiadea.
Black alder forests in the Plitvice Lakes NP were created by successive processes in non-forest areas after their fall out of use (Figure 1). They grow by watercourses in karst depressions with occasionally stagnant surface water. Here the river courses are slowed down and distanced from the slopes and surrounding massifs, hence zonal forests do not have a dominant influence on the floral composition.
The researched forests are classified in the class Alnetea glutinosae Br.-Bl. et Tx. 1943, order Alnetalia glutinosae Tx. 1937, and alliance Alnion glutinosae Malcuit 1929. They exhibit greatest similarity to the Central European association Carici acutiformis-Alnetum glutinosae. However, these results should not be generalized for the entire Dinaric region of Croatia. Detailed studies of black alder forests in the Dinarides are pending and their results will determine their nomenclature and syntaxonomic character.

Key words: Alnus glutinosa; Natura 2000 habitat type 91E0*; National Habitat Classification (NHC); floral composition; Plitvice Lakes National Park

    VUKELIĆ, Joso      ŠL
    Irena Šapić  
    Giacomo Mei  
    Igor Poljak  
    Ivana Plišo Vusić  
    Marko Orešković  
A. Paletto, T. Laktić, S. Posavec, Z. Dobšinská, B. Marić, I. Đordjević, P. Trajkov, E. Kitchoukov, Š. Pezdevšek Malovrh  UDK 630* 907 + 585 (001)
Nature conservation versus forestry activities in protected areas - the stakeholders’ point of view      
Implementation of nature conservation policy follows two main approaches: the segregation approach based on the spatially separation of protected areas from productive areas, and the integration approach based on the integration of productive and conservation purposes. In many cases, the implementation of nature conservation policy has increased conflicts due to different and competing land use principles, interests, and point of views.
The aim of this study is to analyse the stakeholders’ opinions towards possible conflicts, opportunities and obstacles for human activities, and constraints on forest management related to establishment of a new protected area. The study was structured in three main steps: stakeholder analysis, questionnaire survey, and statistical analysis of the collected data. A semi-structured questionnaire was administered by email to a sample of stakeholders in each county involved in the COST Targeted Network TN1401 “CAPABAL” (41 stakeholders in 10 countries). The data were statistically processed to highlight differences between EU28 member countries and non-EU28 countries, and among groups of interest (public administrations, actors of forest-wood chain, universities and research institutes, environmental Non-Governmental Organizations).
The results show that the most common type of conflict is that related to the procedure for the establishment of a new protected area with special regard to property rights restrictions and additional bureaucracy. In addition, the results show that the most important opportunity is for the rural development of the marginal areas with special regard to the eco-tourism development, while the most important obstacle is the decrease of forest management practices (loggings) due to the nature conservation constrains.
The stakeholders’ point of view is a fundamental starting point to reduce conflicts between nature conservation and human activities and to increase the social acceptance of the nature conservation policy.

Key words: protected areas; Natura 2000 network; participatory process; conflicts; consultation; questionnaire survey

    Alessandro Paletto  
    Tomislav Laktić  
    Stjepan Posavec    ŠL
    Zuzana Dobšinská  
    Bruno Marić  
    Ilija Đordjević  
    Pande Trajkov  
    Emil Kitchoukov  
    Špela Pezdevšek Malovrh  
Daniela Pilarska, Manana Kereselidze, Gernot Hoch, Andreas Linde  UDK 630* 453 (001)
Spore viability of microsporidian species isolated from gypsy moth larvae (Lymantria dispar) after long-term storage in liquid nitrogen      
Data on the viability of microsporidian isolates from Lymantria dispar after long-term storage in liquid nitrogen are presented. Eight microsporidian isolates from L. dispar were tested for their infectivity against L. dispar larvae: ­Vairimorpha disparis, Nosema lymantriae, Nosema portugal, Nosema sp. (Poland), Nosema sp. (Ebergassing), Nosema sp. (Germany), Nosema sp. (Schweinfurt) and Nosema sp. (Veslec). The survival of spores in liquid nitrogen was ­studied in detail for N. portugal and Nosema sp. (Ebergassing) which had been stored in liquid nitrogen almost 19 years and used for individual per oral infections while the other six isolates were used only in surface contamination per oral experiments. Our study confirms that storage in liquid nitrogen is a suitable option for long-term storage of Nosema and Vairimorpha species from lepidopteran hosts. Spores survived for up to 19 years; however, the experiments show that there is a significant loss of viability. In some cases, spores had lost viability already after 7 years in liquid nitrogen. We recommend producing fresh material every 5 years to maintain collections in liquid nitrogen. No material that had been stored in liquid nitrogen for extended periods should be used for infection experiments.

Key words: microsporidia; spore viability; long-term storage; liquid nitrogen

    Daniela Pilarska  
    Manana Kereselidze  
    Gernot Hoch  
    Andreas Linde  
Ender Bugday, Abdullah Emin Akay  UDK 630* 383 + 686 (001)
Evaluation of forest road network planning in landslide sensitive areas by GIS-based multi-criteria decision making approaches in Ihsangazi watershed, Northern Turkey      
Forest roads are one of the fundamental infrastructures in carrying out forestry activities and services. According to FAO, approximately 20 percent of the world’s forest lands are covered mountain forests. Since forests are generally located also in mountainous areas with steep slope in Turkey, difficulties experienced in these mountainous conditions render the provision of services difficult while increasing the costs. The aim of this study is to evaluate forest road planning alternatives which are to be developed in landslide sensitive mountainous areas based on the Landslide Susceptibility Mapping (LSM). For this purpose, a total of 12 models were generated with different multi-criteria decision making (MCDM) approaches including Modified Analytical Hierarchy Process (M-AHP), Fuzzy Inference System (FIS), and Logistic Regression (LR). As a result of the study, the best model was Model 3 obtained with LR approach (area under the curve (AUC)=76.6%) value followed by LR-Model 4 (AUC=75.7%) and FIS-Model 4 (AUC=73.4%). Model 3 (AUC=71%) was the most successful M-AHP approach. Consequently, the application of these methods will provide an advantage in making more accurate and more rational decisions during road network planning in landslide sensitive forest areas.

Key words: landslide susceptibility; forest roads; modified-AHP; fuzzy inference system; logistic regression

    Ender Bugday  
    Abdullah Emin Akay  
Velid Halilović, Jusuf Musić, Muhamed Bajrić, Dževada Sokolović, Jelena Knežević, Amer Kupusović  UDK 630* 453 https://doi.orig/10.31298/sl.143.7-8.5 337
Fuel and lubricants consumption during timber felling and processing in the area of p.j. Forest office „Zavidovići“      
Chainsaw is the main tool for work in a phase of wood felling and processing of forest harvesting in BiH. The aim of the research was to determine fuel and lubricant consumption of the chainsaws Husqvarna 365 and Dolmar PS – 7310 in the phase of felling and processing of wood assortments at the area of P.J. Forest Office „Zavidovići“, forest compartment 203. The volumetric method was applied for the measurement of fuel and lubricants consumption, with precise determination of fuel and lubricant quantity in chainsaw tanks. In total 140 trees of the sessile oak were felled (70 trees with
chainsaw Husqvarna 365 and 70 trees with chainsaw Dolmar PS – 7310) during the research. The diameter at the breast height of felled trees ranged from 15 to 84 cm, while tree height ranged from 10,3 to 37,2 m. The total volume of processed assortments was 180,11 m3. The average fuel consumption per m3 processed assortments was 0,306 L/m3 for trees felled by chainsaw Husqvarna 365 which is for 0,042 L/m3 larger in comparison to chainsaw Dolmar PS – 7310 with average fuel consumption of 0,264 L/m3. The average lubricant consumption per m3 processed assortments was 0,102 L/m3 for trees felled by chainsaw Husqvarna 365 which is for 0,012 L/m3 larger in comparison to chainsaw Dolmar PS – 7310 with average lubricant consumption of 0,09 L/m3. Considering conducted research it can be assumed that there are differences in fuel and lubricant consumption between this two type of chainsaws for considered working conditions, but differences are not statistically significant.

Key words: chainsaw; fuel consumption; lubricant consumption; Husqvarna 365; Dolmar PS -7310

    Velid Halilović  
    Jusuf Musić  
    Muhamed Bajrić  
    Dževada Sokolović  
    Jelena Knežević  
    Amer Kupusović  
Zdravko Dolonec  UDK 630* 148.2 (001)
Nestbox occupancy by the great tit (Parus major L.) in young deciduous forest stands      
Conservation of the biodiversity of the forest ecosystems is becoming one of the priority issues in the forest management. Birds play an important role in the overall life of the forest ecosystem, for instance, as an important component of the trophic chains. Recent studies worldwide suggest decline in the population size and richness of the forest bird species, especially those nesting in the cavity of the forest trees. Special emphasis is placed on the secondary cavity nesters. In contrast to the primary cavity excavators, which are making a tree cavity by themselves, secondary cavity nesters for their nesting use cavities made by the primary cavity excavators or natural cavities formed by gradual wood decay process. In order to maintain bird diversity in the forests with a lack of nesting cavities, installation of the nestboxes is an important strategy in many countries. This applies mainly to young deciduous, coniferous stands, and monocultural plantations and areas afforested with exotic tree species. In this paper, occupation of the nestboxes in the young deciduous stands was investigated. According to some researchers, the colour of the nestbox and its height above the ground could be important factors of the nestbox occupation in some bird species. In this study, a total of 120 standard wooden nestboxes were used (60 green and 60 brown). Nestboxes were installed in pairs on a single tree, at a height of 4.0 to 4.5 m (“high” position) and 2.0 to 2.5 m (“low” position). On the first tree, the green nestbox was in the “high” position, on the next tree in the “low” position and so on. The aim of this study was to determine the degree of occupancy of the nestboxes with a respect to the colour and the position on the tree. Because of the intra- and interspecific competition, only one of the nestbox pair was inhabited. Of the total 60 nestbox pairs, 44 (73.3%) nestboxes were occupied; 35 (79, 5%) by a Great Tit (Parus major) and 9 (20.5%) by a Blue Tit (Cyanistes caeruleus). Great Tits occupied mainly “green” nestboxes (88.6%), with no significant differences in the height position of the chosen nestbox. In conclusion, the colour of the nestboxes is more important factor than the height position on the tree during the occupation of the nestboxes by a Great Tit.

Key words: Great Tit; Parus major; secondary cavity nesters; nest-box occupation; young deciduous forest

    Zdravko Dolonec  
Damir Klobučar, Silvije Orsag  UDK 630* 906 + 766
Analysis of using a financial leverage in company „Hrvatske šume“, Ltd      
Business success for business owners depends on the achieved earning power but also on choosing methods of financing their companies. Summing up, the opportunity of choosing methods of financing can be observed through the financial leverage rule. The rule states that the income for business owners can be increased through an opportune use of debt, in comparison to the income they would yield if the debt was not used.
This paper first examines possible approaches to the analysis of the opportune use of a financial leverage and isolates the best approach as the one which excludes the burden of spontaneous financing. After that, an analysis of concrete data of the company Croatian forests, Ltd is conducted, for the period between 2005 and 2015. The company manages most forests and forest land (2 million ha) owned by the Republic of Croatia. The company’s headquarters is in Zagreb. The share capital is HRK 1.171.670.000.00.
The opportunity of using financial leverage is usually shown in the ratio of return on equity (ROE) and return on assets (ROA) (Table 1). The paper measures the ratio through the difference between ROE and ROA. If the difference is positive, the use of a leverage was opportune and vice versa (Figure 5). This type of assessment of opportune leverage use hides a burden of spontaneous financing which is a result of business decisions, and not the decision of methods of financing. Therefore, the first idea of the paper was to test the effectiveness of an analysis of an opportune use of a leverage through the modified indicator called the financial leverage effect (Expression 4, Figure 6). Through a deductive approach, which was also confirmed by the empirical research, we have concluded that this indicator also shows the same burden of the rating of the financial leverage use connected with spontaneous financing. For that reason, we modified the standard ROE/ROA analysis by using three cases. The first case started with complete assets and total liabilities and equity (Expression 5-7). The second case had only interest-bearing liabilities so that the total asset was decreased for the amount of non-interest-bearing liabilities, which means that only the asset financed by equity and interest-bearing liabilities was taken into consideration (Expression 8-10). The third case was constructed for emphasizing the influence of suppliers as one of the most significant forms of spontaneous financing (Expression 11-13). The definite rating of an opportune use of financial leverage is possible only through using the second case where the yield on equity and asset is observed only through the ration of ROE and ROA calculated for assets financed by equity and interest-bearing liabilities.
In the analyzed time period, Croatian forests Ltd., achieved a positive result and a positive net profit (Figure 1, 2, 4). One possible conclusion might be that the company’s business was successful. Naturally, the conclusion of a company’s business success should be based on whether the net profit is satisfactory from the owner’s point of view. An additional question, which was also the subject of this research, relates to the whether the use of a financial leverage in the analyzed company was opportune or not. The answer to that question is provided by the management’s assessment of the choice of financing mode. In other words, whether the company’s choice of financing has increased or reduced earnings for owners.
The standard analysis of the ROE and ROA ratio showed that the use of a leverage was opportune only between 2006 and 2007 and in 2015 (Figure 5). A somewhat different rating is given by the use of indicators of the financial leverage effect (Figure 6). The key difference between these two ratings is connected to the intensity of aggregated indicators. After the conducted analysis of the opportune use of financial leverage by modifying the calculation of ROE and ROA for spontaneous financing, a final conclusion can be made about the opportune use of financial leverage in Croatian forests Ltd. (Figure 7,  8).
Based on the definitive analysis of the opportunity to use the financial leverage (Case 2) in Croatian forests Ltd. in the period from 2005 to 2015, we concluded that, the general speaking, the management used the financial leverage poorly. In other words, the management used debt whose price was too high in relation to the company’s earning power. For this reason, the owners of the company made a smaller return than the company would have done, had it not been indebted. The only opportune financial leverage was used in 2015 where debt had a lower interest rate than the return on assets (Figure 8).
The reasons for the unsuccessful use of the financial leverage should not be sought only in excessive loans (Figure 3). A very low earning power had a huge impact on the unsuccessful use of the financial leverage (Figure 1, 2). The breakthrough point for poor earnings was 2012, from which steady growth is recorded. It is precisely as the result of this turnaround that the achieved level of the profitability of assets was high enough that the use of financial leverage can be assessed as opportune in the last year of the analyzed sample (Figure 8).

Key words: forestry; effect of financial leverage; return on equity; return on asset; cost of debt

    Damir Klobučar  
    Silvije Orsag