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An Approach to In Situ Evaluation of Timber Structures Based on Equalization of Non-Destructive and Mechanical Test Parameters
No full textThis paper addresses the challenges in evaluating the structural performance of built structures using non-destructive methods and in situ tests. Such an examination of structural properties, without their sampling, is a diagnostic improvement, especially for historical heritage buildings, where it is not allowed to violate their physical integrity. Therefore, the research proposes a non-destructive testing method based on the equalization of the mechanically and non-destructively determined parameters of the strength of built-in timber. The research included three phases: (1) a preliminary examination; (2) a calibration procedure of the non-destructive method, and (3) in situ application of the established non-destructive method. The preliminary examination involved testing specimens using X-rays and ultrasonic waves by directing them, analogous to mechanical testing, in the fibers' longitudinal, radial, and tangential directions. In the second phase, it was shown that equalizing the parameters of mechanical and non-destructive testing using ultrasound and X-rays of timber was feasible. Furthermore, mechanical calibration was conducted to establish an applicable non-destructive in situ method. Finally, in the third phase, an in situ assessment of timber architectural elements confirms the effectiveness of the suggested non-destructive approach in diagnosing architectural structures
Analysis of financial reports of pe "NP Fuška Gora"
No full textFinancial reports are a value presentation of the impact of those changes on the financial structure, business success and changes in cash flows of a company. The aim of the research is the financial analysis of the operations of the public enterprise (PE) "NP Fruška Gora". The purpose of the research is to identify problems in business and indicate opportunities for improving the economic efficiency of the business of PE "NP Fruška Gora". The subject of research is balance sheets and profit and loss accounts of company. In the conducted research, the elements of business indicators and business efficiency essential for the analysis of financial indicators of the PE "NP Fruška Gora" were analyzed. Data from the company's balance sheet and income statement were used as material. The following methods were used in the work: a. Financial indicators: liquidity, solvency, indebtedness and b. Performance indicators: productivity, efficiency, profitability. Based on the data from the balance sheet, we can see that the company used funds from credits or loans. By increasing the value of real estate, plant and equipment, and by reducing long-term receivables, the fixed assets of the company also increased, which as of 2018 increasing. The company operated with a business profit for 4 years in a row. In 2014, 2015, 2019, 2021, the company suffered a loss from financing. At no time was the company liquid due to high liabilities. In the period 2014-2021, the company was always solvent. The company needs to improve the labour productivity parameter, which is constantly decreasing. The company generally operates efficient from the point of view of indicators of overall and regular operations, and by observing the indicators of the economy of financing. If all obligations were to be reduced, the indebtedness factor would also be reduced
Genofond drvenastih vrsta SP „Šuma košutnjak” : konzervacija i održivo korišćenje
No full textПубликација која је пред вама представља
проширени приказ дела резултата истражи-
вања која су спроведена током израде сту-
дије „Идентификација и мониторинг генофонда
ретких, рањивих и угрожених врста биљака СП
„Шума Кошутњак“, чији је наручилац Секрета-
ријат за заштиту животне средине града Бео-
града, а реализатор Универзитет у Београду –
Шумарски факултет (Уговор број V-01 401.1-56
од 12.6.2019. године).
Циљ истраживања је био да се идентификују,
попишу, георефернцирају и картирају ретке,
рањиве и угрожене биљне врсте, на подручју
споменика природе „Шума Кошутњак”, као ос-
нова за њихов мониторинг, конзервацију и одр-
живо коришћење у времену и простору. Истра-
живања је реализовао мултидисциплинарни тим
истраживача са Шумарског факултета, Универ-
зитета у Београду; Института за шумарство, Бе-
оград; Института за молекуларну генетику и ге-
нетичко инжењерство, Универзитета у Београду
и Универзитета Сингидунум - Животна средина
и одрживи развој, под руководством др Мирја-
не Шијачић-Николић, редовног професора Уни-
верзитета у Београду - Шумарског факултета
Results of the use of iMammalia and Agouti applications for game monitoring in Serbia
No full textIn Serbia, there is an abundance of diverse game thanks to favourable natural
habitat conditions. However, the current system of game population monitoring
and their habitats in Serbia has numerous shortcomings and is lagging behind
modern and the best monitoring systems (e.g. in Slovenia, Hungary). This paper
analyses the main problems in the use of iMammalia and Agouti applications
by citizens and hunters in Serbia, as well as the results on game obtained using
these applications. These implemented activities were an integral part of two
major international initiatives (MAMMALNET and EOW), funded by EFSA (European Food and Safety Authority) through the scientific project ENETWILD (www.
enetwild.com). A total of 1,012 records on mammals were collected on the entire
territory of Serbia using the iMammalia application (period from 8 May 2016 to 12
May 2023), of which the largest number of records were accepted as valid (n = 938
or 92.7%). The dominant game species are roe deer (n = 334), wild boar (n = 165),
brown hare (n = 155), badger (n = 83), fox (n = 73) and jackal (n = 72), followed by
red deer, squirrel, hedgehog, brown bear, wolf, marten, fallow deer and wildcat.
The Agouti application was applied in the analysis of a large number of collected
images (n = 25,000) using 12 camera traps installed in the period July-October
2022 at 36 randomly selected locations in the part of the hunting ground “Studenica” with an area of about 6,000 ha. This forest-mountain hunting ground is
located in central Serbia near the town of Kraljevo and is managed by a hunting
association. Various species of game have been recorded, the most common
being roe deer, wild boar, marten, fox, dormouse and squirrel. It is estimated
that the density of the wild boar population in the studied part of the hunting ground “Studenica” is 2.2 ind/km2, while for roe deer a much higher density
of 14.0 ind/km2 was estimated. It is concluded that both applications can help
to obtain important new data and significantly improve the system of game
populations monitoring in Serbia, so their use by citizens and hunters should be
continued in the coming period, particularly in a much larger number of hunting
grounds throughout Serbia
Genetic diversity of the Quercus robur L. Population from the Protected area „Košutnjak Forest” (Belgrade, Serbia) assessed by nuclear microsatellites
No full textPedunculate oak (Quercus robur L.) is one of the economically and ecologically mostimportant deciduous forest tree species in Europe. In recent decades, there has been anevident decline of pedunculate oak forests, caused by various factors, such as climate change,site conditions, over-exploitation, or insufficient and inadequate regeneration. In Serbia, thisspecies usually occurs in the valleys of major rivers (Danube, Sava, and Morava), and the mostvaluable pedunculate oak forests grow along the river Sava in the area of Srem, where thereare individual specimens aged hundreds of years. The protected area „Košutnjak Forest“(Belgrade, Serbia), occupies 267 ha, with numerous forest tree species, among which are fivenative oak species, including the pedunculate oak. Oaks can be categorized as „at-risk” speciesin „Kosutnjak Forest”, since their populations are mostly represented by very old trees, with apoor possibility of natural rejuvenation. This research aimed to determine the geneticvariability of the pedunculate oak population in the „Košutnjak Forest” using nuclearmicrosatellites. DNA extraction was performed from young leaves, collected from 56 adulttrees, using a commercial peqGOLD Plant DNA Mini Kit (PEQLAB). In total 13 nuclearmicrosatellites were used, and values of standard genetic diversity parameters werecalculated using GenAlEx 6.5 software. The number of alleles per locus ranged from 8 (MSQ13and PIE239) to 39 (QrZAG90), with an average of 17.538. The number of effective alleles perlocus was in the range from 2,498 (QrZAG108) to 23.668 (QrZAG90), with an average of 8.360.The average value of the observed heterozygosity (Ho) was 0.705, and the average unbiasedexpected heterozygosity (uHe) was 0.818. A statistically significant deviation of the expectedheterozygosity from the observed heterozygosity occurs at 5 loci (MAQ4, PIE239, QpZAG104,QrZAG108, and MSQ13). The average values of the fixation index were positive andstatistically significant, indicating an excess of homozygotes. According to the assessment ofthe genetic status, determining the level of genetic variability of pedunculate oak served as abasis for defining in situ conservation measures for the available gene pool in „KosutnjakForest”
Identification of the field elm gene pool in the protected natural area KOSMAJ (Serbia) as a basis for its conservation and sustainable use
No full textThe field elm (Ulmus minor Mill.) is an autochthonous tree species in Serbia that occurs as asecondary species in oak forests. In the forest fund of Serbia, this species is rare/endangereddue to the genetic erosion and disappearance of elms from natural populations, mainly as aresult of Dutch elm disease. In the protected natural area „Kosmaj“ the field elm was identifiedas one of the target species from the aspect of conservation. This research aimed to identify andassess the state of available field elm genepool in the protected natural area „Kosmaj“, as abasis for its conservation and sustainable use. By terrain reconnaissance a field elm gene poolwas identified, representing almost 100 trees: 47 individuals and 8 groups of trees, on an area of652.99 ha. All trees were georeferenced and mapped. The average height of the trees is 10.34m, the diameter at breast height is 15.68 cm, the perimeter is 51.09 cm, while the averagecrown span is 3.95 m. Dry tops or dry side branches of trees, absence of yield for a long period,and weak natural rejuvenation were recorded. The selected trees will be includedinconservation units, which were proposed to conserve the available gene pool in situ. Toconserve the available genepool ex situ, the cuttings from selected mother trees were collectedand the clonal test was established in the greenhouse of the Faculty of Forestry, University ofBelgrade. This clonal test could be a basis for the establishment of a field gene bank in thefuture. It is planned to determine the variability of the selected trees, using morphological andmolecular markers. The initiated activities should contribute to the conservation andsustainable use of the field elm gene pool in the protected natural area „Kosmaj“ and furtherbreeding of the species
Torrential floods prevention
No full textTorrential floods are the most frequent phenomenon in the arsenal of “natural hazards” in Europe and
globe, being the first when it comes to losses, causing huge damage and the loss of human lives. Torrential
events are characteristic both in urban and rural landscapes. Appearance of torrential floods is consequence
of factors which are partly or completely out of man control. Climate, specific characteristics of relief,
distinctions of soil and vegetation cover, social-economic conditions have resulted in the occurrence of
erosion processes and torrential floods. Anthropogenic influence could be increased by irresponsible
activities concerning land use or decreased with preventive activities: spatial planning in endangered
watersheds; afforestation of bare lands, amelioration of degraded forests, meadows and pastures;
appropriate agricultural techniques; application of agroforestry; erosion control measures and torrent
training works. Soil bioengineering works in the headwaters lead to improvement of interception effects
and infiltration-retention capacity of soil. Performing of erosion and torrent control works in line to Nature
Based Solution (NBS) and Land Degradation Neutrality (LDN) could be the way for decreasing of natural
and man-made hazard
SELEKCIJA GENOTIPOVA POLJSKOG BRESTA NA PODRUČJU PIO “KOSMAJ” KAO OSNOVA ZA NAMENSKU PROIZVODNJU SADNOG MATERIJALA VEGETATIVNIM PUTEM
No full textPoljski brest (Ulmus minor Mill.) je vrsta koja u šumskom fondu RepublikeSrbije spada u kategoriju retkih/ugroženih vrsta čija je brojnost znatno smanjenakao posledica holandske bolesti koja je prisutna na području čitave Evrope poslednjih decenija. Smanjenjem autohtone populacije poljskog bresta, šumarstvo jelišeno njegovih dragocenih ekonomskih i meliorativnih vrednosti, a pejzažnaarhitektura uskraćena za upotrebu poljskih brestova u oplemenjivanju urbanihsredina i vangradskih predela. Na prostoru predela izuzetnih odlika (PIO) „Kosmaj“poljski brest je autohtona vrsta, čija je brojnost znatno redukovana, a populacijasvedena na nešto manje od 100 stabala kod kojih, u dužem vremenskom periodu,nije konstatovan urod. Procenjena starost stabala, njihovo zdravstveno stanje,nedostatak prirodnog podmlađivanja i plodonošenja kao i veliki broj faktora kojidovode do genetičke erozije raspoloživog genofonda upućuju na potrebu namenskeproizvodnje sadnog materijala vegetativnim putem. U tom cilju obavljena je selekcija 12 materinskih stabala, na osnovu fenotipskih karakteristika i zdrvastvenogstanja, sa kojih su sakupljene grančice od kojih su formirane reznice. U staklariŠumarskog fakulteta, osnovan je klonski test potomstva u kome je tokom tri meseca praćen procenat prijema i preživljavanja reznica kao i uticaj debljine reznicana njihovo ožiljavanje. Procenat preživljavanja se na kraju istraživanja kretao od0,00% do 49,12% u zavisnosti od materinskog stabla, a prosečan prečnik na sredinireznice za sva materinska stable iznosio je 3,58 mm. Dobijeni rezultati poslužićekao osnova za masovnu proizvodnju sadnog materijala za potrebe konzervacije iodrživog korišćenja genofonda poljskog bresta na ovom području
Training needs assessment of women in the forestry sector in Serbia
No full textRegularly evaluating and adapting training programs of women
is essential for the long-term success of the forestry sector. This
paper aims to investigate women’s needs for training in the
field of forestry expertise, social-, IT- and management-skills in
Serbia. The study employs a mixed methods design and
integrates both quantitative and qualitative data collection and
analysis techniques. Structured online questionnaires were
administered in the period March-May 2021 to 32 female
forestry students and 64 female forest professionals and
private forest owners. In-depth interviews with 13 respondents
further explored training experiences of women in the forestry
sector. Key findings from the survey indicate a strong need for
nature conservation and forest protection, with over 60% of
forestry professionals and 70% of students expressing interest
in such programs. Additionally, forest adaptation to climate
change (61% of forest professionals and forest owners) and
silviculture and forest maintenance (47% of students) training
emerged as a priority. Respondents highlight the need for
training that fosters communication (50% of forest
professionals and forest owners and 63% of students),
teamwork, and cooperation (70% of forest professionals and forest owners and 56% of students). Findings also underscore
the urgency of designing training programs that address
technical skill gaps, as most respondents showed interest in IT
skills development. The results stress the need for
management training initiatives that are geared toward
building diverse leadership skills (time management, managing
teams and projects, planning and goal setting). Qualitative
analysis reveals the significance of mentorship, networking,
self-confidence and soft-skills development. By addressing the
training needs of women, forestry organizations can contribute
not only to gender equality but also to enhanced workplace
performance and innovation
Germination of seeds of callistephus chinensis, celosia argentea and zinnia elegans after treatment with different fertilizers
No full textChinese Aster (Callistephus chinensis), Silver cock's comb (Celosia argentea), common
zinnia (Zinnia elegans) are popular and wide grown annual ornamental plants in Serbia. They
are propagated from seeds and fertilizers are usually applied in substrate before seed sowing
or during the early propagation stages. Fertilizers can promote or inhibit germination,
depending on fertilizer type and on plant species and it is important to test the effect of
different fertilizers in order to obtain rapid and uniform germination. For this reason, the
effect of three commercial fertilizers (EkoBooster 1®, Unistart and Bakterije) on germination
of Chinese Aster, Silver cock's comb and common zinnia was tested. Substrate was treated
with fertilizers before seed sowing and on 2nd, 3rd and 9th day after seed sowing. Obtained
results differed considerably depending on plant species. The highest germination rate of C.
chinensis was recorded after the treatment with EkoBooster 1® (56%), while the germination
of C. argentea after the treatment with EkoBooster 1® was the lowest (48%) compared to the
other treatments (66.7% - Bakterije, 74.7% - Unistart), even lower than the control (56%).
Tested fertilizers did not have an effect on Z. elegans germination because differences among
recorded germination rates, including the control treatment, were not statistically significant
and the germination ranged from 68% to 76%