|DISORIENTATION IN PRIVATE FOREST MANAGEMENT
|This column has frequently viewed the condition and methods of state forest management from a variety of aspects. This year, when we celebrate the 250th anniversary of Croatian forestry, we record upward and downward trends in the past period, which have generally been influenced by the political situation. After about 50 years of a significantly rising trend, the past several years have witnessed stagnation and then a downward trend. The reasons for this is the irresponsible abandonment of the principle of sustainable management and the comprehensive use and management with the forest as a renewable resource and a highly complex ecosystem, and the comparison of a forest to a factory plant.
State owned forests (about 78 %) are managed by the company Hrvatske Šume Ltd. What about private forests, however? Naturally, they are managed by private forest owners. According to the Forest Law, these forests should be managed in the same way as state forests. Article 8 of the Forest Law states that the Company, but also the forest owners, are obliged to manage forests by sustaining and advancing biological and landscape diversity and by taking care to protect the forest ecosystem. Among the 12 items, one states that tending and cutting a forest should be performed in such a way as not to inflict permanent damage to the ecosystem ... Under Article 9, all forest owners have a duty to manage their forests in accordance with management plans ... Article 10 stipulates that all those concerned should repair the damage from devastation, illegal felling or clearing of forests. What we would particularly like to point out is contained in Article 13 of the Forest Law, which says that the timber felled in the forest and outside the forest, as well as other forest products, may be extracted from the forest only if they are adequately marked and if they are accompanied by adequate documents. Do private forest owners observe the Forest Law, who controls this and in what way? More recently, there have been almost daily reports from the field of uncontrolled felling actions, one might even say ruthless „pillages“ of private forests. Who is in charge of marking trees for felling and are the trees marked at all, who classifies the assortments and where do dubious labels on the assortments come from, how and with what documents are the assortments exported and finally, can all this function so well without some shady deals being made? Do certain private forest owners take advantage of the difficult economic situation, on their own accord or under someone´s coercion, believing that everything is allowed in a problem situation, while quasi entrepreneurs are becoming obscenely rich? Even if an action is undertaken to stop this, we have to wonder if the whole thing will end in the same way in which the action against the theft of gravel ended?
Otherwise, forest management plans have so far been approved by the Ministry on the proposal of the company Hrvatske Šume Ltd, but now this is done by the Advisory Service for Private Forests. We say now, because until 2006 all services in private forests were approved and generally well performed by the state company (Forest Entrepreneurship, Public Company Hrvatske Šume, and then Hrvatske Šume Ltd). The care of private forests was entrusted to forest experts and smaller departments. As early as 2003, the European Union passed a number of declarations, conventions and directives aimed at supporting rural development and highlighted the importance of private forests in terms of sustainable development. About 40 % of the subsidies related to forestry. This was the main incentive for the Government of the Republic of Croatia, on the basis of the Forest Law (OG 140/05), to pass a Directive on 2nd July 2006 concerning the establishment of the Forest Advisory Service with public jurisdiction. The Service was, however, abolished in 2010 due to financial reasons (it was considered parallel (double) cost), and the affairs were returned to the company Hrvatske Šume Ltd. On November 14th, 2013, the Croatian Parliament discussed a Proposal on changes and amendments to the Law on the Agricultural Advisory Service, and the competent Minister explained why the changes were necessary (the use of EU funds for rural development as early as 2014), as well as the reasons for changing the name and for the urgent procedure. Thus, according to the new Law on the Advisory Service, forestry was „engulfed“ in the somewhat changed and amended Agricultural Advisory Service, now under the general name of „Advisory Service“. This service is a specialized public institution for advisory affairs in the field of agriculture, rural development, fishing and improvement of management of privately owned forests and forestland. It acts through the central office and its branch offices (21). As seen from above, forestry has once again been excluded from the name and placed at the end of the sentence as an afterthought, because our „highly capable“ negotiators with the EU forgot that Croatian forestry with almost 80 % of state forests is not just one little part of agriculture as it is in the EU. Damage is now being compensated by drawing the means only through rural development. The new Law and Statute of 27th February 2014 again took the jobs related to private forests from the hands of the company Hrvatske Šume Ltd. According to the reports from the field, the efficiency is questionable, to say the least.
Disorderly land registers, the organisation of which the state continuously shuns despite the fact that almost all the expected investments and development depend on their settlement, small private forest holdings, the unwillingness of private forest owners (with a few exceptions) combined with insufficient help by the state to merge, which would ensure coherent forest areas for rational management according to the principle of the ideal share, are the causes of the chaotic situation. In vain are management plans for private forests when these forests are reduced to a cadaster plot, however big/small it may be. Merging into cooperatives, like in the EU, would make it possible to employ forest experts who would manage forests in the name of private forest owners according to the Forest Law and who would be the responsible partners of the Advisory Service and the competent Ministry. Judging by the current situation, there are no such integrations and the question is whether the legalized system can function successfully.
|IZVORNI ZNANSTVENI ČLANCI
|Darko Bakšić, Nikola Pernar, Ivan Perković, Boris Vrbek, Vibor Roje
|UDK 630*114.2 (001)
|DISTRIBUTION OF ALKALI EARTH METALS AND ALKALI METALS (Ca, Mg, K, Na) IN THE FOREST SOIL OF MEDVEDNICA NATURE PARK
Alkali earth metals and alkali metals Ca, Mg, K and Na are a constituent part of the lithosphere rocks and belong among the 8 most abudant elements in the Earth´s crust. They are the results of the weathering of rocks on the surface of the Earth´s crust in the process of pedogenesis. From the aspect of plant nutrition, these elements belong to plant nutrients: K, Ca and Mg belong to macro-elements or essential elements, while Na belongs to beneficial elements.
The goal of this research is to establish how the lithological bedrock, or parent material in the area of Medvednica Nature Park affects the Ca, Mg, K and Na content in the soil, and whether their spatial distribution is conditioned by the relief as well as by the lithological bedrock.
A total of 181 composite samples were taken in the Medvednica NP forests. Topsoil samples to a 5 cm depth were taken in a regular 1 x 1 km grid. Twenty-eight pedological profiles were opened and evenly distributed to encompass all lithological units. Soil pH values (HRN ISO 10390:2005) were measured in topsoil samples and so was the content of the elements Ca, Mg, K, and Na after extraction with aqua regia (HRN ISO 11466:2004). Determination of particle size distribution in mineral soil material (HRN ISO 11277:2004),
determination of soil pH ( HRN ISO 10390:2005), determination of organic carbon and total nitrogen after dry combustion (HRN ISO 10694:2004; HRN ISO 13878:2004), mineral content of the soil (XRD) by X-ray diffraction method and content of the elements Ca, Mg, K and Na after extraction with aqua regia (HRN ISO 11466:2004) were determined in the samples taken from genetic horizons in the pedological profiles.
For statistical purposes, the lithological bedrock was divided into seven characteristic lithological units, which were used by geologists Halamić et al. (2001) in their study of stream sediments on Medvednica. Lithological unit LIT1 is made up of parametamorphic rocks, Lithological unit LIT2 is composed of orthometamorphic rocks, Lithological unit LIT3 consists of igneous rocks, Lithological unit LIT4 is formed of Mesozoic clastic rocks, Lithological unit LIT5 is comprised of Tertiary clastic rocks, Lithological unit LIT6 consists of Mesozoic carbonate rocks and Lithological unit LIT7 is made up of Tertiary carbonate rocks.
Statistical analysis was performed in Statistica 7 software package. Descriptive statistics was made for all the analyzed variables: number of samples, minimum, lower quartile, median, upper quartile, maximum, mean, standard deviation, coefficient of variation, standard error of mean and skewness. In order to eliminate the effect of outliers and extreme values, the median was taken as the mean value. Mutual differences between the analyzed values per lithological bedrock were tested using the Kruskal-Wallis non-parametric test. Type 1 (a) error of 5% was considered statistically significant.
The highest pH value was recorded for the topsoil layer in LIT6 and LIT7. LIT6 has statistically significantly higher pH value than LIT1, LIT2, LIT3, LIT4 and LIT5, while LIT7 has statistically significantly higher pH value than LIT2, LIT4 and LIT5. Statistically significant positive correlation between pH values and Ca concentrations were found in all lithological units. Statistically significant positive correlation between pH values and Mg was also established for LIT1 and LIT5, and between pH values and K for LIT2 and LIT4. In terms of Mg concentration, two groups were clearly identified: one consisting of LIT4, LIT5 and LIT7 with lower concentration, and the other comprising LIT2, LIT3 and LIT6 with higher concentration, while LIT1 is between the two groups.
The following soil types were determined in the opened pedological profiles: dystric cambisol, eutric cambisol, calcocambisol, pseudogley on slope, colluvium and luvisol (50% – 18% – 14% – 11% – 4% – 4%). In general, the humus-accumulative horizon on Mt Medvednica is shallow – the median is 3.3 cm, and the mean is 3.9 cm. The next horizon, which is usually cambic, is 31 cm and 33 dm thick. The range of organic C content in the humus accumulative horizon ranges from medium humic to very humic soil. The soil is rich to very rich in total nitrogen, and the C/N ratio is favourable. The soil texture is most frequently silty loam, while on the carbonate bedrock it is of somewhat heavier – silty clay loam. The content of individual minerals, and of Ca, Mg, K and Na in the humus-accumulative and mineral horizon is more or less equal, while the correlation between the horizons is statistically significant (p<0,01). For quartz it is r = 0.81, muscovite/illite r = 0,68, chlorite r = 0,76, feldspate r = 0,69, Ca r = 0,85, Mg r = 0,88, K r = 0,82 and Na r = 0,52. The highest pH values and Ca, Mg, K and Na concentrations in beech-fir forests were recorded in the surface soil layer at a depth of 5 cm in LIT3. A statistically significant difference in Ca concentration was found between LIT3 and LIT2 and in Na concentration between LIT3 and LIT1.
The obtained Ca and Mg concentrations in the topsoil of Medvednica Nature Park are in accordance with the values recorded in Central Croatia by Halamić and Milko during their work on the Geochemical Atlas of the Republic of Croatia (2009). The data for all the obtained elements concord with the results obtained from a study of the condition of forest soils in Europe (Vanmechelen et al., 1997). The relief (elevation, inclination, exposition, curvature) do not affect the spatial distribution of Ca, Mg and Na in the topsoil to a depth of 5 cm. Although there is a statistically significant correlation between elevation and Mg concentration, and slope and Mg concentration, this correlation is actually conditioned by the lithological bedrock. Beech-fir stands developed on the soils above basic igneous rocks are characterized by a higher Ca, Mg, K and Na content, and consequently higher pH values. As a result, a higher number of neutrophilic species can be expected in these forests.
Key words: alkali earth and alkali metals; Medvednica Mount; forest soil
BAKŠIĆ, Darko ŠL
PERNAR, Nikola ŠL
PERKOVIĆ, Ivan ŠL
VRBEK, Boris ŠL
|Vinko Paulić, Damir Drvodelić, Stjepan Mikac, Goran Gregurović, Milan Oršanić
| UDK 630* 271 + 174
(Aesculus hippocastanum L.)(001)
|ARBORICULTURAL AND DENDROECOLOGICAL ANALYSIS OF THE CONDITION OF HORSE CHESTNUT (Aesculus hippocastanum L.) TREES IN THE TOWN OF VELIKA GORICA
The paper analyses vitality, health condition, mechanical stability and growth of horse chestnut trees (Aesculus hippocastanum L.) which represent one of the traditional urban green landmarks in the town of Velika Gorica. Following the Visual Tree Assessment protocol biological (vitality) and structural (static) condition of young and old horse chestnut trees was acquired. Vitality assessment was done according to scale 1 – 5 and Roloff model (0–3). Correlation analyses of climatic conditions (temperature and precipitation) and tree index chronology was conducted via DENDROCLIM software. Researched young trees of horse chestnut had similar dendrometrical variables (breast height diameter, tree height, crown radius, tree distance), while old trees showed difference in respect to location which was conditioned by different age of trees, crown topping and site conditions. Tree breast height diameters are statistically different when three research locations are compared. Younger trees growing in park manifested significantly higher vitality compared with those trees growing in tree alley which is explained by better general growing conditions. Best tree vitality was measured in old trees growing in park while the opposite side of the scale was represented in tree alley along the railway station, while best vitality according to Roloff model was measured in tree lane in Zagrebačka street and on the opposite side of the scale was represented by trees growing in park. According to the assessed symptoms and tree defects younger trees growing in park had smaller percent share in respect to younger trees growing
in tree alley in Zagrebačka street. Highest percent share of given symptoms and tree defects at old horse chestnuts trees was assessed in Zagrebačka street and near the railway station while smaller percent share was recorded in park. Visual tree assessment with resistography revealed two of older trees which need to be removed due to their mechanical breakdown resulting with heightened risk on humans and property. Dendrochronological analysis revealed sensibility in radial increment of measured trees (0.08–8.17 mm). Significant positive correlation of radial increment with average spring precipitation and limiting effect of maximum spring air temperatures was determined.
Key words: arboriculture; vitality; static state of tree; horse chestnut; dendroecology; Visual Tree Assessment – VTA
DRVODELIĆ, Damir ŠL
MIKAC, Stjepan ŠL
ORŠANIĆ, Milan ŠL
|Adrian Enache, Tibor Pentek, Valentina Doina Ciobanu, Karl Stampfer
|UDK 630* 383 + 686 (001)
|GIS BASED METHODS FOR COMPUTING THE MEAN EXTRACTION DISTANCE AND ITS CORRECTION FACTORS IN ROMANIAN MOUNTAIN FORESTS
Extraction distance is an important factor used for locating new forest roads. Correction factors should be used for adapting theoretical models to real life situations. The aim of this study was to show how extraction distance and the correction factors can be computed and used for assessing forest road options in a more efficient and effective manner using process automation in GIS. The study was located in a mountain forest in the South Central Carpathians of Romania. For determining the mean extraction distance, 71.5 km of skid trails were tracked in the field and mapped in GIS. Four computing methods were defined: raster method, grid point method, buffer strips method and centre of gravity method. For testing and validating the methods, four infrastructure scenarios were defined: one was describing the existing forest infrastructure and three others were proposing new road options. Statistical analyses were performed for testing the accuracy and the possible differences between methods. The paired samples t-tests revealed significant differences between scenarios proposing new forest roads and the current infrastructure conditions. The raster method, the grid point method and the buffer strip method reported high accuracy for computing the mean extraction distance. This study reported an extraction correction factor (ks) value of 1.50 and a total correction factor (kt) value of 3.40 which can be used for rough calculations in practice. The automation models developed in GIS improved the efficiency of computations. The correction factors determined in this study were comparable with those reported in literature, highlighting the reliability of the analysed methods.
Key words: mean extraction distance; forest roads; road network planning; model; process automation; GIS
PENTEK, Tibor ŠL
Doina Ciobanu, Valentina
|Neculae Şofletea, Marius Budeanu
| UDK 630* 561 + 564 + 535
(Picea abies (L.) H. Karst)(001)
|RESPONSE OF NORWAY SPRUCE (Picea abies(L.) H. Karst) SEED STAND PROGENIES TESTED UNDER DIFFERENT SITE CONDITIONS
The aim of this study was to analyse the response of 33 seed stand progenies of Norway spruce, originating from the Romanian Carpathians, in terms of growth and wood characteristics, in trials located inside (Brețcu and Gurghiu) and outside (Avrig and Câmpina) of their natural distribution. Thirty years after planting, measurements were performed for the following traits: total height (TH), average volume per tree (AV/T), radial increment (RI), latewood percentage (LP) and conventional wood density (CWD). Correlation coefficients between the evaluated traits, on one hand, and the geographical coordinates (latitude, longitude and altitude) and ecophysiological latitude of seed stands origin, on the other, were also determined. ANOVA revealed significant (P < 0.01) differences among populations for all traits, with the exception of RI, suggesting that it is possible to make a selection at the populations level. Generally, the most valuable populations for TH and RI originate from Eastern and Western Carpathians. High values for LP were recorded mainly for populations originating from Eastern Carpathians. Compared to the two trials installed inside the natural range, the values for RI, TH and AV/T diminished only in one of the two tests installed outside the natural range (Câmpina), but the value for CWD increased. This pattern of expression of traits in the two trials located outside the natural range was explained by the different climatic conditions in two areas: the thermo-pluviometric factor in May-September period (TPV-IX) is 25.3 in Avrig, and only of 21.7 in Campina trial. On the other hand, on overall and in all the Carpathians branches, for latewood proportion there was a significant decrease (P<0.001) in the two tests outside the natural range. Significant interaction (P<0.001) between population and site trial was found for RI, TH, LP and AV/T. At the same time, the traits analyzed showed low intensity correlations between their values in the four trials and geographical location (altitude, latitude, longitude and ecophysiological latitude) of seed sources origin. The IUFRO standard provenance (Moldoviţa) was one of the most valuable population for the ensemble of all trials. The results of this study allowed the identification of the best populations in each trial that can be used to establish new plantations in similar ecological conditions.
Key words: comparative trials; Norway spruce; quantitative traits; radial increment; wood density
|Marno Milotić, Osman Mujezinović, Mirza Dautbašić, Tarik Treštić, Daniela Pilarska, Danko Diminić
|UDK 630* 453 + 443 (001)
|FIRST RECORD OF GYPSY MOTH ENTOMOPATHOGENIC FUNGUS Entomophaga maimaiga Humber, Shimazu & R.S. Soper IN BOSNIA AND HERZEGOVINA
The fungal pathogen Entomophaga maimaiga Humber, Shimazu & R.S. Soper (Enthomophthorales: Entomophthoraceae) was found in the north-east Bosnia and Herzegovina populations of Lymantria dispar L. (Lepidoptera: Erebidae) in summer 2013 at 5 localities (Figure 1, Table 1). Since the first introduction of this pathogen in Bulgaria in 1999 several southeastern European countries confirmed its presence in subsequent years. Recent findings of this pathogen in the neighbouring countries, especially in Croatia and Serbia, and also regarding to the progradation of L. dispar populations in some parts of Bosnia and Herzegovina, attracted the attention of the researchers on the possibility of finding this highly selective fungal pathogen. The sampling localities were selected based on pre-collected data of reported L. dispar population progradation, but also to the relative geographical vicinity regarding the new Croatian positive sites with E. maimaiga fungal pathogen. Large areas were aerially sprayed with a Bacillus thuringiensis kurstaki – based bacterial insecticide and larval development was closely inspected in the field. In the last 70 years, from the first reported outbreak of L. dispar in Bosnia and Herzegovina, many outbreaks have been reported, causing the supstantial economical and ecological damage in forestry but also in agriculture production. Biological insecticide based on the
Bacillus thuringiensis kurstaki, commonly used for the suppression of the local populations of L. dispar, does not always produce the desired impact. Consequently, the highly selective, host specific, fungal pathogen that could be put in use as a biological control agent of the L. dispar populations is found to be very interesting for both science and professional application thus deminishing the economical and ecological negative feedback of this indigenous defoliator. The research was carried out during July 2013 throughout the north-east part of Bosnia and Herzegovina where gypsy moth populations continued an ongoing outbreak. From five selected localities, where excessive mortality was observed, larval cadavers were sampled from tree trunks 0,5 – 1,5 m above the ground. Only older larval stages (L4 – L6) were sampled due to the late sampling period. Cadavers were inspected, and larval tissue samples were prepared under the stereo microscope (LEICA Leitz MZ8) and light stereo microscope (Motic SMZ – 168 TLED). Process was digitaly documented with Olympus SP – 500UZ digital camera equipped with the Olympus QuickPHOTO CAMERA 2.3 digital imaging software. Larval tissue samples were inspected under light microscope (Olympus BX53) and images were recorded by digital camera Motic MoticamPro 252A. Measurements of azygospores and conidia (conidiospores) were made via digital imaging software Motic Images Plus 2.0 and Motic Images Advanced 3.2. associated with a compound microscope. Microscopic analysis of the dead tissue larvae, in all five locations, confirmed both conidia and azygospores or azygospores only, of the E. maimaiga species. Spore dimensions were as follows: pear-shaped conidia crosswise 25,7–35,1 µm and 34,6–43,7 µm lenghtwise; azygospores 32,2–47,9 µm in diameter (Figure 2, Figure 3). The type of spores (conidia or azygospores or both) that will form after host death is determined by the pathogen and the type of host infection, host-related factors and environmental conditions. Macroscopic symptoms of E. maimaiga attack were easily recognizable on the tree trunks along with some signs of larval mortality caused by Lymantria dispar multicapsid nuclear polihedrosis virus (LdMNPV) (Figure 4). There were very few signs of parasitoid mortality, but unlike in the Croatian sites (Hrašovec et al. 2013), with a great abundant presence of gypsy moth predators like Calosoma sycophanta L. (Figure 5), which could be an indicator that the pathogen has emerged when the L. dispar population was already starting its descent into a retrogradation phase. Just like in the Croatian localities where the sampling took place (Hrašovec et al. 2013), dead larvae were hanging from the tree trunks head down all through the sites and no living larva or viable pupa could be found in the area. Based on the field collections and microscopic analysis, entomopathogenic fungus E. maimaiga, a pathogen of L. dispar introduced on the European continent, has been confirmed in Bosnia and Herzegovina. Extensive monitoring of the fungal pathogen in the following years will give us the information on pathogen spatial spread, its speed and the possibility for establishing its permanent position among the other local indigenous species. Nevertheless, there are some concerns whether E. maimaiga may show some direct and indirect impacts on non-targeted and beneficial organisms in the future, or change the basic community structure of folivore insect guilds on oaks, maybe resulting in increasing populations of other defoliating insect groups such as tortricids, geometrids and sawflies. These concerns will demand more scientific attention in the future.
Key words: Entomophaga maimaiga; Lymantria dispar; biological control agent; fungal pathogen; spatial spread; mortality; impact; natural enemies; beneficial organisms; defoliators
DIMINIĆ, Danko ŠL
|Peter Boyadzhiev, Mirza Dautbasic, Osman Mujezinovic, Plamen Mirchev, Georgi Georgiev, Margarita Georgieva
|UDK 630* 442 (001)
|Baryscapus transversalis Graham (Hymenoptera: Eulophidae) – A NEW SPECIES FOR THE FAUNA OF BOSNIA AND HERZEGOVINA
Baryscapus transversalis (Hymenoptera: Eulophidae) was established for first time as an egg hyperparasitoid of Thaumetopoea pityocampa (Lepidoptera: Notodontidae) in Bosnia and Herzegovina. It was reared from egg batches of pine processionary moth collected on Pinus nigra in the region of Boracko jezero. In laboratory conditions, 80 specimens of B. transversalis were reared during emerging period of 20 days between 3 and 22 November 2013. In the eggs of T. pityocampa, both males and females of B. transversalis developed, in sex ratio (♀♀:♂♂) 3:1.
Key words: first record; hyperparasitoid; Thaumetopoea pityocampa; Bosnia and Herzegovina