+ 2008 + 2009 + 2010 + 2011 1-2/2012 3-4/2012 5-6/2012 7-8/2012 9-10/2012 11-12/2012 + 2013 + 2014 + 2015 + 2016 + 2017 + 2018 + 2019 + 2020 + 2021 + 2022 + 2023 + 2024 new HR EN |
3-4/2012 |
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RIJEČ UREDNIŠTVA | ||
Uredništvo | 117 | |
CROATIAN FORESTRY AT THE CROSSROADS | ||
One of the many definitions of a forest states that: "A forest comprises forest soil coherently covered with forest trees, shrubs and ground vegetation, where wood matter is permanently produced and where non-market goods are expressed in the ecological (protective), social and socio-ecophysiological functions of a forest. A forest is characterized by harmony and mutual relationships between the living community or biocoenosis (plants, animals, microorganisms) and site (soil, climate, relief)". Therefore, when we talk about forests, we talk about air, water, climate, soil, landscape and plant and animal world. Forestry is a science, profession and art of managing this highly complex ecosystem to the benefit of mankind and nature. Croatian forestry is proud of its 250 years of tradition in managing forests according to the principle of sustainability, and of, until recently justly declared harmony of education, science, practice and even forest policies (competent ministry), united in the Croatian Forestry Association. The result of this unity is the exceptionally well preserved condition of Croatian forests. In the past 10 years, however, with politics penetrating almost all the pores of forestry, expertise and scientific know-how has been increasingly neglected (to the point that the term "forestry" has been deleted from the name of the ministry!). Unity fostered for decades has been severely undermined. Here are just a few examples: there are differing opinions related to the construction of the Danube-Sava Canal, which seriously threatens the survival of tbe Spačva forests (and about which the competent bodies of the forestry operative remained silent); next, there is no agreement in connection with the introducti on of the Natura 2000 protection concept, which comprises large forested areas, and the most productive continental stands in particular. For the second time, politics has decided to cut down on the means for OFKŠ (Non-Timber Forest Functions), despite the well known fact that these funds are invested into the sustenance of non-timber forest functions and forestry science. Hence, all economic subjects, who are also keen users of these functions, have the obligation to set aside the means for this purpose. The Croatian Forestry Society has discussed many topics of interest, including the worrying fact that the Forestry Strategy is still lacking. There has also been talk about the new Forest Law and about concessions on forests. Yet, professional debates which would provide guidelines to the solution of forestry problems and which would put a stop to speculation and even to justified fears for forests and forestry, are nowhere to be seen! The fact that around 80% of the forests in terms of surface area (and almost 90% in terms of value) are state-owned and that they are managed by the company Hrvatske Šume Ltd, which employs about 8,000 people, including a large number of highly qualified forestry experts, justifies the interest of the profession in the policy of the new Management Board. Sadly, we still have the impression that all is shrouded in a veil of secrecy; we sometimes get a glimpse of things from an interview in the press, or else some "directives leak out". Profit is a "must" word – it is just that we are not sure that those in authority valorise profit in forestry adequately; in other words, we fear that they only value wood matter from the afore mentioned definition, naturally, respecting the management plan, and not making profit by not applying, e.g. silvicultural treatments, as has been the case recently, instead of taking into account all the other goods provided by a forest, which are far more important and valuable. We hear about surplus workforce, while at the same time "non-forest activities" will be put up for lease (does this mean that forestry workers are not capable of retraining and that private entrepreneurs have adequate specialist workforce in excess?!). A part of surplus employees would receive paid years of work, we assume, in order to "improve the structure of the employed in relation to the retired". There are engineers who are employed part time for as many as three consecutive years. Now, their contracts will be terminated despite the fact that their profile is needed in production, which is in stark collision with the proclaimed care for young experts. If it is true that in future, according to the "directives", dedication at work will be valorised with 65% and knowledge with 35%, then welcome to "Croatia – Land of Knowledge"! We have given here some food for thought; naturally, there are many more issues that need discussing, so it is only natural that we require and expect answers and solutions. Still, we have the impression that now politics is trying to save itself from itself by increased politicisation. Finally, let us mention a slight "transformation" of our journal, which we have initiated with the goal of modernizing its visual profile and achieving its even better positioning among the current European and world scientifi c and specialist publications. We hope that the changes will be welcome and accepted. Naturally, we are open for further improvements. The Editorial Board of Forestry Journal wishes to retain firm contacts with its readers, especially in the hard times awaiting us all. Editorial Board |
authors: Uredništvo | |
IZVORNI ZNANSTVENI ČLANCI | ||
Maja Jurc | UDK 630*453 (Phyllonorycter issikii) (001) |
119 |
The Lime leafminer (Phyllonorycter issikii) in Slovenia | ||
Summary: From 2007 to 2008, a study of presence of the lime leafminer (Phyllonorycter issikii) in Slovenia and an attack of different species of the genus Tilia (Tilia cordata, T. platyphyllos, T. tomentosa, T. sp.1, T. sp. 2) in six ecological regions at 22 sites in urban areas was carried out. The aim of the study was to determine the extent of lime leafminer in Slovenia and investigate whether the localities, ecological region, hosts species and years affect the moth population density, the damage to the leaves, and the number and surface of mines in the leaves of different host plants. A total of 918 leaves were analysed; measuring the characteristics of leaves (average leaf area, total number of mines, the average size of mine) was done by scanning, and calculations with the program Digimizer 3.0.0.0., MedCalc Software. Ph. issikii is present throughout Slovenia. Damage to leaves and moth population density was greatest in the Pre-alpine, Pre-panonic and Alpine ecological regions; the largest mines were in the Pre-alpine, Alpine and Pre-panonic ecological regions. Among native limes, the most commonly damaged is T. cordata (91.47%), followed by T. platyphyllos (21.72%), then T. tomentosa (0.41%). By far the greatest damage was appearing on the hybrid lime T. sp.1 (512.5%). Damage to the leaves in the period of investigation was high: 87.8% on average; in 2007, it amounted to 116.3% in 2008 to 66.5%. The surface of mines in the leaves was higher in 2007 year than in 2008 (39.3 mm² compared to 21.4 mm²).
According to the size (surface) of mines, the results showed that there were statistically significant differences between sites in relation to surface of mines on a leaf. The largest surfaces of mines were in the leaves at the locations 19 (Vrt oddelka-Ljubljana), 20 (Pernica) and 21 (Ižakovci); there were significant differences between ecological regions in relation to the surface of mines on a leaf. Larger surfaces of mines were identified in the Pre-alpine region (92.2 mm²) and the Alpine region (59.6 mm²). There are significant differences between tree species in relation to surface of mines on a leaf; greater surfaces of mines were found on the leaves of T. sp.1 (165.3 mm²); finally there are significant differences between years in relation to surface of mines of the leaves. Surface of mines were larger in 2007 compared to 2008. There were significant differences between sites in relation to the number of mines on a leaf; sites 19 (Vrta oddelka – Ljubljana) and 21 (Ižakovci) (5.1 and 3.9) stand out in this regard. There were also significant differences between ecological regions in relation to the number of mines; the Pre-alpine region (2.9) is predominant. There were also significant differences between tree species in relation to the number of mines on a leaf; species 4 (T. sp.1) (5.13) stands out in this regard. Finally, there were significant differences between years in relation to the number of mines on a leaf. This number was higher in 2007. Ph. issikii was discovered in Slovenia in 2006, but we assume that it appeared in Slovenia prior to 2006, considering the distribution of species throughout the country. Due to the relatively large amount damage to the host leaves, we believe that Ph. issikii is a significant pest species of the hosts from the genus Tilia in parks and trees in park-like forests in urban areas. This paper also gives recent data on the range and hosts of the lime leafminer; in Asia, it is indigenous in three countries, while in Europe it has expanded in 20 countries. In natural distribution, its hosts are local species of linden (Tilia spp.); in Europe its hosts are also linden hybrids, as well as exotic species of limes. Key words: Europe Slovenia; Phyllonorycter issikii; Tilia spp. |
authors: Jurc, Maja | |
Ivan BALENOVIĆ, Ante SELETKOVIĆ, Renata PERNAR, Maša Zorana OSTROGOVIĆ, Anamarija JAZBEC | UDK 630*521+522+531 (001) | 129 |
Regression models of dbh estimation for photogrammetric maesurement | ||
Summary: Since it is impossible to measure diameters at breast height (dbh) directly from aerial photographs, existence of reliable dbh estimation models is crucial for the application of photogrammetric method in forest stands measurements. Research of relationships and creation of mathematic models for correlations between diameter at breast height and tree variables measured on aerial photographs (crown diameter, tree height, tree number etc.) was therefore the object of numerous scientific studies.
Main goal of this paper was to create the regression models for main tree species (Sessile oak, Common beech, European hornbeam and Black alder) dbh estimation in "Donja Kupčina–Pisarovina" forest management unit of uneven-aged, privately owned, forests located at hilly regions (Figure 1). These models would serve as a prerequisite for the application of photogrammetric method in forest stands measurements, by using contemporary tools and digital photogrammetry techniques. Based on the former studies, and keeping in mind the heterogeneous structure of the researched stands, in dbh modelling were used two independent variables. First model (dM1) used crown diameter and tree height, while second model (dM2) used crown projection area and tree height for the above mentioned variables. Field measurements of stands’ structural elements (diameter at breast height, crown diameter and tree height (Figure 2)) needed for creating regression models was conducted on the sample of 383 trees in total (103 Sessile oak trees, 103 Common beech trees, 127 European hornbeam trees and 50 Black alder trees), distributed through 6 chosen compartments (16 to 21) at "Donja Kupčina–Pisarovina" forest management unit (Figure 1). Conducted partial correlation confirmed the statistical significance of all independent variables (crown diameter, crown area and tree height) planned for model creation (Table 1). Multiple regression analysis confirmed the statistical significance of all created models – both model types (dM1 – Table 2 and dM2 – Table 3) and all tree species (Sessile oak, Common beech, European hornbeam and Black alder). Modelling results have shown that independent variables crown diameter and tree height from the first model (dM – Table 2), as well as the crown projection area and tree height from the second model (dM – Table 3) explain the variability of diameter at breast height with high values of determination coefficients (R2 > 0,76). By comparing the results based on tree species between different model types, it was determined that the first model for Sessile oak and Common beech shows better results – 4% higher values of determination coefficient, and lesser error values in dbh estimation, expressed through root mean square error (RMSE), were obtained. For European hornbeam and Black alder both models produced almost identical results regarding R2 and RMSE values. Since crown diameter and tree height variables in Common beech model (dM1) increase the explained dbh variability by only 3%, using the simpler model with crown diameter as the only independent variable is recommended for estimating Common beech diameter at breast height, especially if tree height is not measured during the photogrammetric measuring. Based on the obtained results and regression analysis parameters for each individual model (Table 2 and 3), as well as the results from graphic (Figure 3 to 5) and analytic (Kolmogorov-Smirnov test) testing of each individual model, we can conclude that created regression models can be used for dbh estimation in "Donja Kupčina–Pisarovina" forest management unit of uneven-aged, privately owned forests located at hilly regions, and also in forest stands with similar characteristics. In order to confirm the possibility of practical application for created regression models it is necessary to conduct a photogrammetric measurement of forest stands in "Donja Kupčina–Pisarovina" forest management unit, and to compare the obtained results and the costs of its application to terestrial measurements. |
authors: BALENOVIĆ, Ivan ŠL SELETKOVIĆ, Ante ŠL PERNAR, Renata ŠL OSTROGOVIĆ, Maša Zorana ŠL Jazbec, Anamarija | |
Győző F. HORVÁTH, Dávid SCHÄFFER, Ákos POGÁNY, Dániel TÓTH | UDK 630*451+411 (001) | 141 |
Spatial distribution of small mammal populations in Drava floodplain forest | ||
Summary: In the present study we examined the spatial distribution of the small mammals of a floodplain forest by River Drava based on a three-year live trapping (capture-mark-recapture). We registered the presence of 5 shrew and 5 rodent species between 2001 and 2003. Of them Apodemus agrarius, A. flavicollis, Myodes glareolus and Sorex araneus were generally typical in the region. In our examination striped field mouse was the most frequently recorded species. The habitat use of the Apodemus species was equal, however the habitat use of bank vole was the opposite, preferring the area between the river and the dirt road. This indicates the spatial segregation of the bank vole and the two mouse species. Striped field mice travelled greater distances than bank voles did. Yellow-necked mouse individuals covered significantly greater movement distances than striped field mice. As suggested by our study, the dirt road as a dividing line of the trapped forests had no barrier effect on the movements of individuals of the three rodent populations. Key words: capture-mark-recapture; floodplain forest; small mammals; spatial association |
authors: Horváth, Győző F. Schäffer, Dávid Pogány, Ákos Tóth, Dániel | |
Tzvetan ZLATANOV, Ivaylo VELICHKOV, Georgi HINKOV, Margarita GEORGIEVA, Olafur EGGERTSSON, Saevar HREIDARSSON, Magdalena ZLATANOVA, Georgi GEORGIEV | UDK 630*561+114 (Castanea sativa Mill.) (001) |
153 |
Site index curves for European Chestnut (Castanea sativa Mill.) in Belasitsa mountain | ||
Abstract: Richards, Lundqvist-Korf and Hossfeld growth functions were fitted to age-height data of European chestnut (Castanea sativa Mill.) dominant trees on the northern slopes of Belasitsa mountain, Southwest Bulgaria. The model prediction performance was evaluated using quantitative as well as qualitative examinations. Goodness of fit of each model was estimated by the coefficient of determination, F-test for significance of the regression and t-tests for significance of the coefficients of the model. Models were further compared by the evaluation of the standard error of the model and Akaike’s Information Criteria. Site index curves were constructed following the "guide curve method" procedure. In accordance with the evaluation tests, the Richards function was chosen as most adequate to express the age-dominant height relationship. Accordingly, it was further employed as a guide function to derive site index curves for studied chestnut population. It was recommended that the growth model and the site index curves elaborated in the current study are used within the data range 10−110 years. Key words: Castanea sativa; Guide curve method; height growth; Richards function; site index curves |
authors: Zlatanov, Tzvetan Velichkov, Ivaylo Hinkov, Georgi Georgieva, Margarita Eggertsson, Olafur Hreidarsson, Saevar Zlatanova, Magdalena Georgiev, Georgi | |
Bojana KLAŠNJA, Saša ORLOVIĆ, Zoran GALIĆ | UDK 630*232:232.4+238 (001) | 161 |
Energy potential of poplar plantations in two spacings and two rotations | ||
Summary: The article presents the results which are related to the biomass yield of five poplar clones in the testing phase: P. deltoides cl. ‘B-229’, P. deltoides cl. ’B-81’, P. deltoides cl. ‘182/81’, P. deltoides cl. ‘PE 19/66’, and Euramerican poplar P. × canadensis cl. ‘Pannonia’, in experimental plantations of seven years, with planting space of 6×6 m (278 plants ha–1) on two soil types. Also, the analysis of the biomass yield of the same clones that were established as dense plantations, by sprouting one shoot per stool after harvesting in the experimental plot at the Institute with the planting space 16667 plants ha–1 (1.5 m between rows and 0.4 m within rows). The energy that could be obtained by biomass combustion, on base of wood calorific values for the examined clones has been estimated. It was found that the maximum (annual) weight of biomass, and thus also the energy in SRF plantations, are obtained by the clone ‘PE 19/66’ – 7.236 tha–1, and 134.556 GJha–1, respectively. However, clone ‘B81’, which achieves the maximum values in the SRC plantations (6.617 tha–1 and 121.523 GJha–1), has the least oscillations in all experiments and is very close to maximum values in SRF plantations. Key words: biomass yield; energy; poplar clones; spacing |
authors: Klašnja, Bojana Orlović, Saša Galić, Zoran | |
PREGLEDNI ČLANCI | ||
Igor ANIĆ, Šime MEŠTROVIĆ, Slavko MATIĆ | UDK 630*902 | 169 |
Important events in the history of forestry in Croatia | ||
Abstract: The purpose of this article is to elaborate on the relationship between man and forest in Croatia in the context of historical development of the forestry science and profession. To facilitate reading, the article makes use of list with some important years and events that marked the history of the man–forest relationship and the history of forestry in Croatia in particular. Each event is accompanied by a brief description of its features and data source. The goal is to illustrate the Croatian tradition of the profession, education and science of forests and forestry. This is one of the unique features that we bring into the European Union; the feature that past generations have managed to preserve and guard, taking account of forest sustainability and resources.
Forestry as a science appeared in the 18th century. Its occurrence marks the third period in the man–forest relationship. It sprang from the need for the sustainable use of forest resources and the preservation of forests after deforestation (disappearance of water springs, onset of torrents, soil erosion, formation of bare rock, decrease in soil fertility, loss of forest resources) resulting from intensive cutting operations in the 17th century and the first half of the 18th century. This is the reason that forestry is defined as a science, profession and art of managing and preserving forest ecosystems, whose purpose is to secure permanent benefits to man, society and nature. Forestry is based on the principle of sustainability; defined in 1713, it is still the only proper example of sustainable development and sustainable management. The first written documents that regulate the relationship between man and forests in Croatia date from the 12th century. Forestry in Croatia was established in a very short period in the second half of the 18th century. It all began with the first forest inventory and mapping (1764), the foundation of forest offices (1765 in mountain region, 1773 in lowland region) and the first legally binding Regulation (1769) which introduced sustainable forest management in Croatia. The establishment of the first forest offices as the basic units of the profession can be considered as the official beginning of the development of forestry in Croatia. In three years, Croatian forestry will mark an important jubilee: two and a half century of its existence. In 1846, forestry professionals gathered within the forestry association of the Croatian Forestry Society, which began issuing its scientific-specialist and professional journal Šumarski List (Forestry Journal). The development of the profession was closely followed by the development of higher forestry education. In Croatia, forestry education was provided by vocational schools as early as 1860 and by the University of Zagreb since 1898, after theology, philosophy and law. Forestry is a complex activity that integrates biological, ecological, technical and economic components. It is for this reason that the beginnings of some scientific fields in Croatia emanate from higher forestry education programmes. Forests are the only Croatian self-renewable natural resource and national treasure. They are the source of drinking water, clean air, natural soil, flora and fauna, biodiversity, naturalness, mild climate, attractive landscape and wood material, or in one word, of life itself. As set down in the Constitution of the Republic of Croatia, forests rightly enjoy the status of goods of special interest that have particular protection. Every government in power has been acutely aware of the importance of forests and forestry and has carefully guarded and fostered them. It is no wonder, therefore, that the provided overview contains a set of laws and bylaws, regulations, instructions and directives that relate to forest management. Until recently, the importance of forests was also reflected in the name of the competent ministry, which always contained the word "forest" or "forestry". Forestry was born in the most forested part of Croatia, where it began its two-and-a-half-century long development. It is precisely here that high-quality, productive, and natural forests are still growing. The profession has adhered to scientific principles and regulations to create these forests by applying regeneration and tending operations. The existence, structure, the level of naturalness and biodiversity of these forest ecosystems are the product of Croatian forestry. Key words: Croatia; history of forestry |
authors: ANIĆ, Igor ŠL MEŠTROVIĆ, Šime ŠL MATIĆ, Slavko ŠL | |