|AT THE END OF THE YEAR
|At the end of a year we always ask ourselves in wonder – how did it "fly by" so quickly? We then go on to analyze whether the set programmes have been accomplished and prepare programmes for the upcoming year. Since this column addresses current forestry topics, let us remind ourselves briefly which topics stimulated the thoughts of our readership and drove them to action.
In the double issue 1–2/2013 we reviewed the successful completion of the 45th European Foresters’ Competition in Nordic Skiing (EFNS). The event, held from February 17 to 23 in the area of Delnice and Mrkopalj, was hosted by Croatia. A detailed presentation of the biggest ever meeting of European foresters in Croatia was given in the double issue 3–4/2013. Let us cite the official report of Mr Kaltenbach, the EFNS technical delegate: The 45th EFNS in Delnice, Croatia, was a superbly organized competition that required enormous effort and dedication. There was not one weak point in the technical area. The 45th EFNS 2013 was executed faultlessly and with hearty enthusiasm. All the participants are full of praise.
The double issue 3–4/2013 dealing with the topic "Where did politically biased personnel recruitment and non-market management lead us?" explores a shift from a relatively acceptable political-professional personnel recruitment in forestry to the completely politically based recruitment. This was reflected primarily in the omission of the term "forestry" from the name of the relevant Ministry, in the selection of party-based but insufficiently professional staff and, worst of all, in the appointment of non-forestry staff. For a profession which will mark the 250th anniversary of organized work in forestry in 2015, and whose Faculty marked the 115h anniversary in the year 2013, this is certainly demeaning, to say the least.
The central topic of the double issue 5–6/2013 was "Forestry with and without a tax on non-market forest functions". It was initiated by the announcement of total abolishment of the tax levied for non-market forest functions. We pointed out that the Croatian Forestry Association held a number of meetings devoted to this topic and provided some concrete suggestions regarding the tax. It was interesting to analyze the purposes and the ratios in which the tax was used, and who the biggest tax payers were who would be exempt from paying the tax.
The double issue 7–8/2013 searched for an answer to the question "Do forestry practices disregard the principles of sustainable forest management?" Of the 10 principles of close-to-nature forest management summarized by the Academy Member Dušan Klepac, we highlighted the following (accompanied by comments on the adherence and non-adherence to these principles): managing a forest as a renewable natural resource by safeguarding the forest ecosystem; adequate forest management as sustainable management that maintains the commercial, ecological and social forest functions, and the selection of the optimal organisational form in forestry. The last sentence says: "There is no progress in forestry without science and culture", which is often forgotten.
The double issue 9–10/2013 deals with a document by the European Commission Secretary General that was sent to the EU Council and the EU member states for acceptance. The report relates to the "The new EU forest strategy: for forests and the forest-based sector". We concluded that we almost completely agree with the principles contained in the proposed Strategy, since it reflects precisely the issued we have been advocating for years. We expect the Croatian Forest Strategy to finally see the light of day. It should be pointed out that the Strategy regards forestry as a particularly important axis of regional development
The last double issue of this year deals with the question : "Who will draw up this Strategy (or under whose guidance it will be drawn up), considering that the relevant Minister, Deputy Minister and the managing director of the company Hrvatske Šume Ltd are not forestry experts? At the same time, the Faculty of Forestry, the Academy of Forestry Sciences and the Croatian Forestry Association have no say in forestry-related issues. Forestry issues have not been discussed at any meetings of the relevant Ministry. Moreover, the Minister of Economy has never even mentioned forestry as an economic branch, and neither has the Minister of Regional Development, although the EU Forestry Strategy stresses that forestry is the main axis of regional development. In fact, not one single politician in Croatia has made an attempt to meritoriously discuss forests and forestry, unlike Dr Danilo Turk, President of the Republic of Slovenia, for example, who read a well received paper on this topic at the Forest Week in Slovenia in May 2009. The paper was published in "Gozdarski Vestnik" (Journal of Forestry), and we published a summary in the Forestry Journal. We advise our readers to read it once again and draw a parallel with our current situation. Forestry features in the media only when an affair is disclosed, whereas expert discussions to which the media is invited arouse no interest.
Hoping that things will change for the better in the upcoming year, we wish Merry Christmas and a Very Happy and Successful Year 2014 to all the readers of our Forestry Journal.
|IZVORNI ZNANSTVENI ČLANCI
|Ivan Perković, Nikola Pernar, Darko Bakšić
|UDK 630*114.1 (001)
|COMPARISON OF TWO SIEVING AND SEDIMENTATION METHODS FOR DETERMINATION OF PARTICLE SIZE DISTRIBUTION – POSSIBILITIES AND LIMITATIONS OF INTERPRETATION
The purpose of this research was to comparison of two sieving and sedimentation methods for determination of particle size distribution (PSD). Until 2009, PSD was determined at the Faculty of Forestry in Zagreb by a sieve and pipette method after soil preparation using Na-pyrophosphate according to the Pedological manual (old method) (Škorić, 1965). Since the opening of the ecological-pedological laboratory at the Forestry Faculty in 2009, PSD determination has been performed according to the ISO 11277 (2009) Standard. The most important difference between the two methods is that according to the ISO 11227 Standard, pre-treatment is accomplished with hydrogen peroxide which oxidizes the organic matter, so that PSD is determined only in mineral soil particles, while according to the old method, the organic matter was not removed at PSD determination.
The purpose of this research was to establish whether there was a difference in the results of PSD determination between the old method and the ISO 11277 Standard in the overall number of samples and particularly in the topsoil. Another goal was to test the difference in the textural interpretation of PSD results obtained by these two methods.
For the needs of the analysis, 67 forest soil samples were taken from two areas in Croatia. The two methods were compared in order to determine whether there was a statistically significant difference in the total number of the samples. A comparison was also made to determine whether there was a statistically significant difference between the samples taken from the topsoil layer, since according to ISO 11277 the organic matter largely found in the surface soil part oxidizes.
Statistical analysis and t-test revealed no statistically significant difference in any single fraction from the topsoil layer between the old method and ISO 11277. A high correlation was found in the topsoil layer for all the measured fractions (r = 0.98 for coarse sand, r = 0.96 fine sand, r = 0.94 coarse silt, r = 0.84 fine silt and r = 0.97 clay) as well as in the all established samples (r = 0.99 for coarse sand, r = 0.97 fine sand, r = 0.89 coarse silt, r = 0.88 fine silt and r = 0.97 clay).
Based on the classification into three main fractions (sand, silt and clay) a higher percentage of sand and a lower percentage of silt was established by the old method compared with ISO 11277. This difference is directly reflected on textural interpretation. No statistically significant difference between the two methods was found for the clay fraction.
Key words: particle size distribution; soil texture; Na-pyrophosphate; Na-hexametaphosphate; ISO 11277
PERKOVIĆ, Ivan ŠL
PERNAR, Nikola ŠL
BAKŠIĆ, Darko ŠL
|Tarik TREŠTIĆ, Osman MUJEZINOVIĆ, Azra ČABARAVDIĆ, Ismir MURATAGIĆ
|UDK 630*412 (001)
|IMPACT OF MICRO-LOCALITY FACTORS TO THE INTENSITY OF INFESTATION OF SILVER FIR TREES WITH WHITE MISTLETOE
White mistletoe (Viscum album L.) is semi-parasitic plant which in different intensity occurs on numerous deciduous and coniferous tree species. The research on the impact of micro-localities to the intensity of infestation of Silver fir trees with white mistletoe was conducted in April 2012 in forest management area "Ključko", management unit "Šiša-Palež", in parts of units 5, 6 and 7/1 which belong to management class 1211 – Forests of Beech and Silver fir with Spruce on mainly deep calco-cambisole, luvisole and combinations of it on dense limestone and dolomites. According to the valid forest management plan for these forests is predicted a group-selective system of management. As characteristics of the micro-locality of infested Silver fir trees were assessed or measured the following parameters: breast-height diameter, inclination, altitude above the sea level and shading of the crown of infested tree caused by crowns of neighboring trees. The intensity of the presence of white mistletoe on Silver fir trees was assessed by implementation of Hawksworth Index of Infestation
Research covered 517 infested Silver fir trees by the characteristics of which are given in the tables 1–4. It was determined that with the increase of breast-height diameter of tree (diameter class) increases the average index of infestation (Figure 1). By the analysis of variance were determined statistically highly important differences in the intensity of infestation by white mistletoe of trees from different diameter classes (Table 1; F = 9,239; sig. 0,000). In majority of cases, the increase of the inclination of the terrain has caused higher intensity of infestation of trees. However, by the analysis of variance were not determined statistically significant differences
in intensity of infestation by white mistletoe of trees from different inclination category (Table 2; F = 2,237; sig. 0,083). Regarding the altitude above the sea level of the micro-locality, the conducted analyses did not confirm the existence of statistically significant difference in average index of infestation of trees which were located at different altitudes above the sea level (Table 3; F = 1,095; sig. 0,358). The impact of light to the occurrence of mistletoe was researched through the level of shading of infested crown caused by crowns of neighboring trees. By the analysis of variance were determined statistically highly significant differences in the intensity of infestation by white mistletoe of trees from different categories of shading of their crowns (F = 17,761; sig. 0,000). By comparison of all categories of shading was determined a general model which points that the intensity of infestation by mistletoe declines with the increase of the level of shading of the crown of infested tree (Figure 3).
Key words: white mistletoe; Viscum album; Silver fir; Abies alba; intensity of infestation; index of infestation; characteristics of micro-locality.
|Roman ROSAVEC, Zoran ŠIKIĆ, Željko ŠPANJOL, Damir BARČIĆ
|UDK 630*431 + 111 (001)
|INFLUENCE OF METEOROLOGICAL PARAMETERS ON FLAMMABILITY OF SOME MEDITERRANEAN SPECIES
The Mediterranean ecosystems are affected by human activity, and the present situation is largely a result of intensive human activities and natural changes. Meteorological parameters were having a great impact on the fires. As fires are a natural phenomenon, they are small scale with minor damage can be interpreted as a dynamic natural processes. But the number of forest fires, and thus the size of the burned area, have drastically increased in recent decades. The vegetation of the Mediterranean is specific in many ways, including by cause-and-effect relationship with the forest fires. Specifically, each vegetation type has its own fire regime, and features such as fire interval, the average annual burnt area and severity (intensity of fire). Mediterranean forests are generally poor in terms of the number of species represented. Monodominant are, and as such are easily flammable and subject to the spread of fire from a mixed forest with a large number of species. This paper describes the variation of flammability (ID) major tree species of the Mediterranean area and are presented to estimate the effect of meteorological factors on the above variables. Research was conducted on Teaching Experimental Forest Object Rab Faculty of Forestry, University of Zagreb, and in an experimental laboratory for the protection of forests against fire in Makarska. Tests were carried out in the period of June 2007. until June 2009., one month per location. The results were confirmed by differences in delay between the flammability species tested at all sites, as well as the location of the species tested. The mean delay flammability of all kinds at both sites was 10.60 seconds. The results based on laboratory testing show that they can be directly used in the description and prediction of forest fire when it comes to the flammability of natural fuels in actual site conditions.
Key words: flammability; forest fires; meteorological factors; Mediterranean
ROSAVEC, Roman ŠL
ŠIKIĆ, Zoran ŠL
ŠPANJOL, Željko ŠL
BARČIĆ, Damir ŠL
|Matthias KROPF, Gerald HÖLZLER, Rosemarie PARZ-GOLLNER
| UDK 630 * 152 + 135
(Castor fiber L.) (001)
|GENETIC EVIDENCE ON THE ORIGIN OF THE CURRENT BEAVER (Castor fiber) POPULATION IN LOWER AUSTRIA
Beside European beavers (Castor fiber) from Poland, Belarus and Sweden also individuals of C. canadensis have been released to the Austrian Danube watershed east of Vienna during the years 1976 and 1990. Based on reintroduction activities the Lower Austrian beaver population developed well to a current size of more than 3000 individuals. However, it remains ambiguous, which of the originally released animals account for this success. Here, we present mitochondrial (mt) DNA data to answer the questions whether C. canadensis is still traceable in Lower Austria and which intraspecific lineages of C. fiber are currently present?
Our Maximum Likelihood (ML) analysis based on 81 newly generated DNA sequences from the mitochondrial control region plus 30 reference beaver samples from the literature, revealed no evidence for the existence of C. canadensis in Lower Austria. With respect to C. fiber, three different intraspecific lineages (mainly corresponding to different subspecies) were identified. While the majority of samples represent either Scandinavian (subsp. fiber) or Central European beavers (likely C. f. albicus x belorussicus/orientoeuropaeus), one sample of C. f. pohlei was rather genetically distinct and unexpected from the documented reintroduction history. In addition, possible hybridisation among intraspecific beaver lineages is discussed, although the maternally inherited mtDNA analysed here did not give the ultimate answer to this question.
Key words: Castor fiber; Danube; Lower Austria; mitochondrial control region; reintroduction
|Andreas Redin, Göran Sjöberg
|UDK 630*151 (001)
|EFFECTS OF BEAVER DAMS ON INVERTEBRATE DRIFT IN FOREST STREAMS
We aimed to assess the effects of beaver dams on the invertebrate drift fauna in five central Swedish boreal forest streams. Each stream was sampled once during the autumn, with drift traps placed upstream and downstream of the beaver dams. Drift densities (numbers/100 m3 water) were calculated. The invertebrates were determined, dried and weighed. No significant differences were noted in total drift densities or in the drift densities of pelagic species. The drift densities of benthic species were higher upstream of the dam, mainly because Ephemeroptera were more abundant in the upstream part. No significant difference was observed in diversity or dry weight. The functional feeding group ratio: filtering collectors/gathering collectors was significantly higher downstream of the dam.
Key words: stream invertebrates; drift fauna; beaver dam; beaver pond
|UDK 630 *114.4
|THE PREPARATION METHOD OF FOREST SOIL MONOLITHS WITH THE USE OF EPOXY RESIN
In the Croatian Forestry Institute a collection of monoliths of the most important forest soils was produced during the period from 2011 to 2013. The collection was made by means of a new method of attachment and preparation with the use of epoxy resin. After digging the pedological pit, the profile is prepared and a prism of soil, measuring 20 cm x 100 cm and 5 cm thick, is made. With a sharp tool it is then separated from the soil and placed horizontally so that the monolith can be analysed and fixed onto the base. In the case of skeletal soils we gradually move the soil from the marked prism in the pedological profile into the frame according to marked parts. After drying the monolith is fixed with clear matte varnish, following which it can be presented in a vertical position or on the wall of an exhibition area. The new method is less complicated and faster because it does not require a massive monolith in a large box, which is occasionally difficult to transport to the first communication road.
Key words: Soil Monolith; pedology; epoxy resin. Collection of works
VRBEK, Boris ŠL