|The demise of a man who has devoted his life to forests and forestry
|Slavko Matić, Academy member, Professor Emeritus of the Faculty of Forestry and Wood Technology of the University of Zagreb, Doctor Honoris Causa of the Mendel University of Agriculture and Forestry in Brno (Czech Republic) and the Technical University in Zvolen (Slovakia), member of the presidency of the Croatian Academy of Sciences and Arts, one of the founders and the first president of the Academy of Forestry Sciences in Zagreb, member of the Deans’ Club of the University of Zagreb and long-standing president of the Croatian Forestry Association, passed away on March 30th, 2021, at age 83.
We are not going to discuss his scientific achievements here. His bibliography, available from the web site of the Croatian Forestry Association, fully testifies to his immense scientific legacy, as do numerous awards and recognitions which he received during his rich career of forestry pedagogue and scientist.
Although Slavko Matić’s scientific work focused more specifically on silviculture within the scientific area of biotechnical sciences, his broad spectrum of activities left an indelible mark on the whole era of forestry history at the end of the 20th and the beginning of the 21st century.
His life path was determined by his love for forests and forestry. He would often say that forestry was not only a profession but also a way of life. He staunchly advocated and promoted the unity of forestry policy, science, education and profession.
His words, spoken at the 107th annual assembly of the Croatian Academy of Sciences in Županja illustrate his mission and his understanding of the forestry profession. „We are proud of our long tradition marked above all by the utmost care for forests and forestry of Croatia. We would like all those who are actively involved in this profession to do their best in order to improve the quality and eternity of forests. We have always believed and we still believe that all our efforts and love invested in the forest will be paid back manifoldly and permanently, but not in enormous and unnecessary material goods, but in the satisfaction and knowledge that we belong to a profession in which work, love and honesty are the basic principles and laws. Without these principles it would not be possible to raise and maintain forests today, whose structure and worth rank them among the most beautiful and valuable in Europe. These beliefs allow us to cultivate and preserve forests in the state in which they provide both market and non-market goods, goods dedicated to every person in this country”.
He was the protector of forests and the forestry profession in every sense of the word. We still remember vividly how our professor would “storm and thunder” if something was not done according to the rules of the forestry profession. It might have been a number of things, such as the conversion of forests and forestland for the needs of building infrastructure or for agricultural production, when construction interventions would be undertaken in the affected zone with negative impacts on the forest ecosystem (the Danube-Sava Canal, the Zagreb Project on the River Sava, hydropower stations on the River Drava, the Kalje forest). He also frequently spoke against the policy of passive forest protection promoted by the Croatian Ministry of Environmental Protection, stressing felling as a means of tending forests.
When interventions were made in forests which went against the principles of the Zagreb School of Silviculture, of which he was one of the founders, foresters knew with certainty that it was Professor Matić who would react and respond adequately.
He openly opposed the payment of the water fee for forests and forestland, while at the same time they are the only ones that ensure a natural water regime and provide clear water. He always highlighted the importance of non-market forest functions and viewed timber as a side product of forest management.
He considered the Croatian Forestry Association as his second home. Here, we would often discuss in detail issues related to forests and forestry.
He expressed dissatisfaction with the current policy towards forestry, which systematically neglected the interests of the forestry profession, particularly after the word forestry was omitted from the name of the corresponding ministry. He was also saddened by the fact that a number of our colleagues who, under the influence of politics, put the conformism of current managerial functions above the forestry postulates we were taught at the faculty.
The demise of Professor Matić ends a period which we, his contemporaries, will always look upon as an unforgettable experience of living a noble foresters’ life in togetherness, the result of which are well-tended and preserved forests.
Will the new trends increasingly visible in present day forestry, in which foresters have less and less contact with forest and with their colleagues, be able to respond to all the challenges, particularly in conditions of growing climate changes, remains to be seen.
|IZVORNI ZNANSTVENI ČLANCI
|Tomislav Poršinsky, Vitomir Kajgana, Željko Tomašić, Andreja Đuka
| UDK 630* 453 (001)
|Gradeability of the cable skidder based on traction performance
Based on the dimensional characteristics of the cable skidder (dimensions, weight, position of the center of gravity), a model was developed for estimating the mobility of the skidder during timber extraction (skidding) uphill in a safe, efficient and environmentally sound way. The model is based on the limiting slope of skidders’ mobility depending on the traction performance of the vehicle, which connects two research approaches, 1) vehicle – terrain (distribution of forces depending on the slope and load) and 2) wheel – soil (traction performance based on wheel numeric). The model is in compliance with a number of restrictions arising from previous research: i) unloading the front axle of the vehicle, ii) overloading the rear axle of the vehicle, iii) minimum longitudinal stability of the skidder, iv) minimal soil bearing capacity and v) allowed tyre load capacity.
The results of the mobility of the cable skidder Ecotrac 55V equipped with 12.4-24 tires during skidding timber uphill, differ significantly with regard to the load-bearing capacity and the load size. For smaller loads, weighing up to 1 ton, the mobility of the skidder is determined by the criteria/limits of the skidder gradeability (traction performance) and environmental benefits (minimum load-bearing capacity). As the weight of the load increases, apart from the load-bearing capacity, the decisive limiting factor of mobility becomes the load ratio of the front and rear axles of the vehicle (> 1: 3.5), which limits the mobility of the skidder on slopes <33% for loads of 1.5 tons, <20% for 2 tons. At a load of 2.5 tons, the mobility of the skidder is affected by the criteria of the maximum allowable load of the rear axle of the skidder on slopes <7%.
Key words: cable skidder; uphill skidding; gradeability; traction performance
PORŠINSKY, Tomislav ŠL
TOMAŠIĆ, Željko ŠL
|Krunoslav Sever, Dimitrije Damir Sviličić, Tomislav Karažija, Boris Lazarević, Željko Škvorc
| UDK 630*232.3 (001)
|Photosynthetic response of common beech seedlings to suboptimal mineral nutrition
This paper presents the results of measuring parameters that describe the photosynthetic activity of beech seedlings under suboptimal mineral nutrition. The aim of paper was to present the issue of mineral nutrition of forest trees to forestry practice through the discussion of the obtained results in the context of previous knowledge about the impact of mineral nutrition on the photosynthetic process of forest trees. In the early spring of 2019, beech seedlings originating from a natural mixed stand of sessile oak and common beech were transplanted into a sterile substrate (agroperlite). After transplanting, the seedlings were regularly watered (treated) with a complete nutrient solution (KO treatment), and nutrient solutions in which nitrogen (–N treatment), phosphorus (–P treatment), magnesium (–Mg treatment) or iron (–Fe treatment) were omitted. The following parameters were regularly measured on six seedlings within each of the five previously described treatments during the 2019 growing season: rate of photosynthesis (A), stomatal coonductance (gs), intercellular concentration of CO2 (ci), relative chlorophyll content index (CCI) and the photosynthetic performance index (PIABS). All parameters were worse in seedlings from –N, –P and –Mg treatment compared to seedlings from KO treatment. Such a result is probably due to the physiological functions of N, P and Mg that participate in the structure of proteins and enzymes, energy turnover and storage, and the structure of chlorophyll, which together are necessary for the proper functioning of the overall photosynthetic process. Despite the important role of Fe in all life processes of plant, including photosynthesis, all measured parameters in seedlings from –Fe and KO treatments were very similar.
However, unlike N, P and Mg which belong to the group of macronutrients, Fe belongs to the group of micronutrients whose concentrations in plant tissue are relatively low. Therefore, it is possible to assume that the investigated seedlings from natural stand soil and/or from seed reserves during the initial phase of their development could absorb and/or retraslocate enough Fe for normal functioning throughout the growing season, regardless of subsequent treatment. Given such a results, initial monitoring of photosynthetic activity parameters will be continued over the next few growing seasons. In this period, it is planned to start monitoring the vegetative growth dynamics, leaf phenology and the development of visual symptoms under suboptimal mineral nutrition of beech seedlins in order to further approximate this issue to forestry practice
Key words: Fagus sylvatica; beech; seedlings; photosynthesis; mineral nutrients
SEVER, Krunoslav ŠL
Dimitrije Damir Sviličić
ŠKVORC, Željko ŠL
|Ahmet Lojo, Jusuf Musić, Besim Balić, Admir Avdagić, Velid Halilović, Aida Ibrahimspahić, Jelena Knežević
| UDK 630* 523 (001)
|Modeling bark thickness of beech (Fagus sylvatica L.)
Thickness and share in volume of tree and/or round wood represent the most important features of the bark, especially in the process of timber harvesting, during scaling of processed logs. In forestry of Federation of B&H there are no rules or tables for deduction of double bark thickness based on scientific research. Wood assortments tables for our most important tree species, besides a whole series of wood assortments, also contain the category of waste. From a practical point of view this category can be divided into “real waste” and losses. The real waste in this sense consists of various logging slash and sawdust, while the loss constitutes a prescribed method of measuring the dimensions and calculation of volume and the deduction of the double bark thickness. So, it is very important to have relatively accurate data of the bark thickness for certain tree species. Therefore, the objecti ve of this paper is to explore double bark thickness and share of bark in the volume of beech round wood. The research was carried out in the area of the Canton 10 of Federation of B&H. The research included 678 sample trees from 10 cm to 85 cm diameter breast height (DBH) and from 5 m to 40 m of height with 6,403 pairs were measured for double bark thickness and diameter in the middle of the round wood (section). Data of double bark thickness in relation to mid diameter of round wood were equalized by following equation with coefficient of determination R2=0.722.
The results of research confirmed the regularities defined in previous research and has shown as follows: a) by the increase of mid diameter of round wood, double bark thickness increases from 6.05 mm (thickness class 12.5 cm) to 20.69 mm (thickness class 82.5 cm), b) by the increase of mid diameter of round wood, bark share in the volume decrease exponentially from 9.44 % (thickness class 12.5 cm) to 4.95 % (thickness class 82.5 cm).The research have indicated the need to use the results and incorporating it into applicable rules of deducting the bark on logs or share of bark in the volume depending on diameter over the bark.
Key words: beech; bark thickness; bark share; round wood
|Tark Çtgez, Refik Karagül, Mehmet Özcan
| UDK 630*114.1 + 116
|Evaluation of the effects of some watershed characteristics on water and suspended sediment yield in agricultural and forest dominated watersheds
Topography, geological structure and land use play a determinative role in the streamflow and total suspended sediment yield of watersheds having similar climate, soil and vegetation characteristics. In order to facilitate sustainable water resource management and effective land use planning, there is an increasing need for research investigating the effects of these factors. This study was carried out in forested and agricultural dominated subwatersheds of the Big Melen watershed in the Western Black Sea Region of Turkey. Hazelnut plantations are grown on most of the agricultural areas in both watersheds. The forested watershed has a steep topography and its geological structure consists of sandstone-mudstone and sedimentary rock. The agricultural watershed area is larger and unlike the forested watershed, there is argillaceous limestone in its geological structure. The precipitation, streamflow and total suspended sediment yield in the watersheds were measured for two years. The total precipitation of the study area over the two years was 2217.3 mm. The water yield of the forested watershed was 867.6 mm, while that of the agricultural watershed was 654.9 mm. In the two years, the total suspended sediment transported from the forested watershed was 19.51 t ha-1 and from the agricultural watershed 7.70 t ha-1. However, except for the high values measured after an extreme rainfall event, the unit surface suspended sediment yield of the agricultural watershed was found to be higher than that of the forested watershed. These findings showed that watershed characteristics such as slope, geological structure and rainfall intensity may be more effective on the streamflow and total suspended sediment yield of the watersheds than land use.
Key words: Big Melen watershed; land use; suspended sediment yield; watershed characteristics; water yield
|Nediljko Landeka, Mirela Uzelac, Danijela Poljuha, Barbara Sladonja
| UDK 630* 453
|The first record of the asiatic string cottony scale Takahashia japonica in Croatia
The Asiatic string cottony scale Takahashia japonica Cockerell (Hemiptera, Coccomorpha, Coccidae) is a species native to Japan. The first record in Europe was observed in Italy in 2017 and again in UK in 2018. In this paper, we provide an overview of the first record of T. japonica in Croatia. First appearance of T. japonica was in 2019 in Pula (Istrian County, Croatia) but the species was determined in spring 2020. In order to collect the field data as efficiently as possible we launched a citizen scientist campaign under title: “A search for an insect – Takahashia japonica”. The campaign was shared to city utility companies in Istria, public institutions of protected areas, NGOs, local newspapers and radio stations. The specific morphology of the eggsacs enabled easy recognition of this species and ensured the accuracy of citizens’ reports. During the campaign we have collected in total seven reports in the city of Pula. The most common host plant of T. japonica was Acer sp. and Morus alba L. some of which have suffered significant defoliation and tree decay. Given the limited infestation and the relatively small number of infected trees, next step is to carry out a complete eradication of the species. The procedures of early detection measures and rapid eradication of invasive pest is in accordance to Regulation no. 1143/2014 of the European Parliament and the Council and by the European and Mediterranean Plant Protection Organization (EPPO). In the end, eradication activities have been agreed with the city utility company Herculanea d.o.o. which is responsible for horticulture and plant protection in the city of Pula.
|Toni Safner, Ana Gracanin, Ivan Gligora, Boštjan Pokorny, Katarina Flajšman, Marco Apollonio, Nikica Šprem
| UDK 630* 461
|State border fences as a threat to habitat connectivity: a case study from South-Eastern Europe
The conservation value of transboundary management of wildlife populations in Europe, that marked end of the 20th and the beginning of the 21th century, has come under huge pressure since 2015 especially in the South-eastern Europe due to border fences construction in response to large influxes of refugees/migrants. The primary aim of this study was to present data on the direct impacts of the long fence on wildlife (e.g. fence-related mortality) across the Hungary–Croatia border. We collected data on fence-related animal mortality along 136 km of the fence in the first 28 months after its construction. In total, 64 ungulates (38 red deer, 23 roe deer, and three wild boar) were found entangled in or deceased due to the razor wire fence. In addition, we present direct (photographic) evidence of newly recorded behaviour of red deer, as they gather in huge herds attempting to cross the border fence between Hungary and Croatia. Short term effect of the border fence is reflected in direct animal mortality, and as obstruction to the movement and behaviour of animals. In the case that current fences will remain or continue to expand along the northern boundary of South-eastern Europe, it is likely that fragmented wildlife populations in the region will suffer from negative effects of genetic subdivision such as loss of alleles and reduced heterozygosity that can cause important long-term damage to their vitality.
Key words: Border fence; Wild ungulate mortality; Habitat fragmentation; Red deer; Roe deer; Wild boar; South-eastern Europe
|Marina Milović, Marko Kebert, Saša Orlović
| UDK 630* 172.8
|How mycorrhizas can help forests to cope with ongoing climate change?
The ongoing climate change have multi-faceted effects not only on metabolism of plants, but also on the soil properties and mycorrhizal fungal community. Under climate change the stability of the entire forest ecosystems and the carbon balance depend to a large degree on the interactions between trees and mycorrhizal fungi. The main drivers of climate change are CO2 enrichment, temperature rise, altered precipitation patterns, increased N deposition, soil acidification and pollutants, ecosystem fragmentation and habitat loss, and biotic invasion. These drivers can impact mycorrhizal community directly and indirectly. We discussed the influence of each driver on mycorrhizal community and outlined how mycorrhizas play an important role in the resilience and recovery of forest ecosystems under climate change, by mitigating detrimental effects of CO2 enrichment, temperature rise, drought, lack of nutrients, soil acidification, pollutants, pests, and diseases. Conservation of the overall biodiversity in forest ecosystems as well as providing the most favourable conditions for the development of mycorrhizae can contribute to increasing the resilience of forest ecosystems to climate change.
Key words: mycorrhizal fungi; forest trees; colonisation; increase of CO2; drought