Omorika Digital repository of the Faculty of Forestry, University of Belgrad
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Silviculture in deteriorated stand conditions and complex societal demands in the area of national park ,,Fruška gora”
No full textPrimena na savremenim osnovama racionalizovanih mera gajenja šuma u cilju održanja i unapređenja šuma na području Nacionalnog parka „Fruška gora” predstavlja najznačajniji segment gazdovanja šumama, imajući u vidu njihovo antropogeno narušeno stanje i namenu. Za unapređenje stanja potrebne su intenzivne uzgojne mere u pojedinim fazama razvoja sastojina, što je suprotno njihovoj permanentnoj pasivnoj zaštiti. Osnovni razlozi za primenu ovih mera nalaze se u izdanačkom poreklu sastojina na preko 82% površine Nacionalnog parka i dominaciji lipe u odnosu na glavne edifikatore (hrastove i bukvu). Na osnovama ekosistemskog pristupa u gazdovanju šumama, a posebno u uslovima sve izraženijih klimatskih promena, mere gajenja šuma je potrebno racionalizovano usklađivati sa biološko-ekološkim zahtevima glavnih vrsta drveća i dominantnim prirodnim procesima u šumskim ekosistemima, odnosno potrebno je uvoditi elemente prirodi bliskog gazdovanja šumama. U radu se, na osnovu raspoloživih podataka i stavova u planskim dokumentima, kao i rezultata sopstvenih istraživanja, ukazuje na najznačajnija opredeljenja gajenja šuma u cilju ostvarivanja njihove posebne namene u Nacionalnom park
Hydrocarbon Contamination of Karst Aquifers - Case Study: Lyda Well-1 (Bowling Green, Kentucky)
No full textThis study analyzes the fate and behaviour of petroleum hydrocarbons in a shallow
karst environment in the City of Bowling Green, KY. The study site is a natural hydrocarbon
seep in this groundwater system monitored at the Lyda Well-1. The groundwater
hydrochemistry of two sampling campaigns (before and after the rainfall event) was
compared. The concentrations of total petroleum hydrocarbons (TPH) in groundwater
decreased from an initial 20.4 mg/l to <1.4 mg/l (after the rainfall event) primarily due to
the advection. The hydrocarbon-contaminated groundwater before the rainfall event was
characterized by decreased O2 and NO3
-
(electron acceptors) concentrations and increased
Mn and Fe content (metabolic products of biodegradation). After the freshwater recharge
and flushing of the well, Mn and Fe concentrations decreased, following a similar trend
as TPH. Similar trends were observed during several sampling campaigns in 2021, thus
providing reasonable to assume that hydrocarbons undergo attenuation processes in the
karst aquifers
ψDOs with radial symbols and spaces of type G
No full textWe investigate various G type spaces on Rd+ and their relations with the Gelfand-Shilov S type spaces on R2d through the mapping w : R2d-* Rd+, w(x, & xi;) = (2x21 + 2 & xi;21, ... , 2x2d + 2 & xi;2d). Sufficient conditions for the hypoellipticity of symbols originating from the coordinante radial symbols in G type spaces are also given. Two open problems explained in the introduction are posed
Agricultural Land Use Changes as a Driving Force of Soil Erosion in the Velika Morava River Basin, Serbia
No full textThe erosion potential model was applied to estimate the soil erosion status of rural settlements during the years 1971 and 2011. We used univariate and bivariate local Moran's I indices to detect and visualize the spatial clustering of settlements with respect to changes in erosion intensity and agricultural land use, as well as their mutual spatial correlation. The study area was differentiated into four statistically significant clusters using the calculated bivariate local Moran's I indices. The statistical analysis examined the two largest clusters, i.e., the high-high and low-low clusters, and the results of the research indicate that the first four principal components explained 70.50% and 73.47% of the total variance, respectively. In the high-high cluster, the low rates of erosion reduction (average Index Z = 98) in the most significant types of rural settlements were determined according to demographic indicators (i.e., the higher population vitality and population density, the smaller share of the old population and the lower average age of the population) and the large proportion of arable land and Neogene sediments. In the low-low cluster, high erosion reduction rates were detected (average index Z = 64). In this cluster, the more statistically significant influence of natural conditions in combination with demographic-agrarian processes (i.e., the larger share of the old population, the higher average age of the population, the lower vitality index and deagrarization) were decisive factors in changing erosion intensity
Ascertaining the Knowledge of the General Public and Stakeholders in the Forestry Sector to Invasive Alien Species-A Pan-European Study
No full textAgainst the background of the phenomenon of globalisation, which has increasingly intensified in recent decades, invasive alien species (IAS) have led to biological invasions that have resulted in multiple negative effects on economies, human health, and especially on the environment. In order to control invasive alien species, preventive actions are considered the most effective methods. In this context, society can actively participate in the process of early detection and preventing the spread of these organisms, but there is a need to raise public awareness. In order for this process to take place in the most efficient way, it is necessary to initially evaluate the knowledge of the general public to IAS. Through a questionnaire that was circulated in ten European countries and had over two thousand respondents, this study aimed to investigate the level of knowledge of some stakeholders in the forestry sector regarding IAS. The results showed that a vast majority of respondents who participated in the study had heard about IAS and provided a correct definition of these organisms. Most of the respondents in this study heard for the first time about IAS from school, the Internet, or journal articles. Data analysis also showed that stakeholders in the forestry sector (foresters, forest owners, and members of environmental NGOs) were more likely than the other respondents to be aware of the impact of IAS. The results of this study offer an insight to researchers and decision makers assessing the differences of opinion regarding invasive alien species, and the necessary steps that could be adopted in the process of raising awareness in society
Main city street transformation framework
No full textThe purpose of this paper is to present the framework of the green transformation of the main city street based on the results of the comparative analysis of the green transformation proposals and realisations done for the main streets of the four European capital cities Paris, London, Vienna, and Ljubljana. Selected cities are important cases because they could be also interpreted as influential examples of the green transformation of renowned or major city streets that broadening the appeal of this topic and represent a model for other public space interventions. Interest of this work is placed on the presentation of the components of the framework divided into two groups that interact with each other - agents of change and sustainable urban structure, as fields of action
Improving the method of lens mass preparation for age assessment in the European brown hare (lepus europaeus)
No full textResearch was conducted on the European hare (Lepus europaeus Pall.), one of the most numerous and important small game species both in Europe and in the Republic of Serbia. The aim of the research was to examine the possibility of modifying the standard method, which is a standard in the Republic of Serbia, for determining the age of hares based on the mass of their lenses in order to shorten its duration. Additionally, the goal was to investigate whether there was a difference in the age structure determined by the standard and modified methods. For the purpose of processing and analyzing samples, a total of 410 hare heads were collected from hunting grounds in Central Serbia and Vojvodina, and only heads with intact lenses of both eyes (399) were included in the analysis, resulting in the examination of 798 lenses. It was determined that there was no statistically significant difference in the lens mass between the standard and modified methods, both for age categories of hares up to one year and over one year. High correlation coefficients were found, indicating a strong relationship between the lens mass obtained by the standard and modified methods within both age categories. Furthermore, the real growth rates of hares determined by the standard and modified methods were equal
Efficiency of different systems of work within tree felling and making of wood assortments : doctoral dissertation
No full textSeča stabala i izrada drvnih sortimenata u Srbiji se u preko 90% slučajeva obavlja motornim testerama. U literaturi se navodi da je posao radnika koji rukuje motornom testerom jedan od najtežih, ali i najopasnijih. Osnovni cilј ovog istraživanja je bila ocena efikasnosti i izbor odgovarajuće organizacione forme rada u seči stabala i izradi drvnih sortimenata u različitim uslovima rada, istovremeno uvažavajući više faktora. Ovo istraživanje obavljeno je na 7 oglednih površina (5 u ravničarskom i 2 u brdsko-planinskom predelu), gde su seča stabala i izrada drvnih sortimenata obavljene motornim testerama Stihl i Husqvarna, koje su se razlikovale po snazi. Istraživane su tri različite forme rada (1M (radnik koji rukuje motornom testerom) +0R (pomoćni radnik), 1M+1R i 2M+0R) u sastojinama različitih vrsta drveća i različitim vrstama seče (čista seča u zasadima topole, proredna seča u sastojini hrasta i prebirna seča u sastojini bukve i jele). Utvrđeno je da postoje statistički značajne razlike u ostvarivanju učinaka između organizacionih formi rada, ali i između vrste drveća. Potrošnja goriva najviše zavisi od prečnika stabla na prsnoj visini, zatim od vrste drveća, a tek onda od snage motorne testere i organizacione forme rada. Utvrđeno je da je se najmanja potrošnja goriva i maziva, ali i potrošnja energije kao i emisija štetnih gasova ostvaruje kombinacijom dve motorne testere u sastojini bukve (jedne veće i jedne manje snage), u organizacionoj formi rada 2M+0R. Utvrđeno je da na štete na preostalim stablima u seči stabla izradi drvnih sortimenata najveći uticaj imaju prečnik posečenog stabla, zatim nagib terena i sklop sastojine, dok na štete na podmlatku najveći uticaj ima veština rukovaoca. Ukupno opterećenje dvojice radnika koji rukuju jednom većom i jednom manjom testerom u proseku je za 11% manje u odnosu na grupu radnika koji rukuju dvema testerama veće snage, pa je i sa ergonmskog aspekta povoljnija varijanta kombinacije veće i manje testere (kao i kod potrošnje goriva i maziva).Felling and processing of wood assortments in Serbia is performed with chainsaws in over 90% of cases. It is stated in the literature that the job of a chainsaw operator is one of the most difficult but also the most dangerous ones. The main goal of this research was to evaluate the efficiency and choose the organizational form of work in tree felling and wood assortments processing under different operating conditions, while taking into account several factors. This research was carried out in 7 sample plots (5 in a lowland area and 2 in a hilly-mountainous area), where the felling of trees and wood assortments processing were performed with Stihl and Husqvarna chainsaws, of different powers. Three different forms of work (1 worker with chainsaw (C), without assistant (A) – 1C+0A, 1C+1A and 2C+0A) were investigated in stands of different tree species and different types of felling (clear felling in poplar plantations, thinning in oak stands and selection cutting in a beech and fir stand). It was established that there are statistically significant differences in the achievement of results between the analyzed organizational forms of work, but also among the tree species. Performance increases with an increase in diameter class in all organizational forms of work. Fuel consumption mostly depends on the diameter at breast height, after that on the tree species, and only then on the power of the chainsaw and the organizational form of work. It was found that the lowest fuel and oil consumption, as well as energy consumption and emission of harmful gases, are achieved when two chainsaws in beech forest (one of higher and one of lower power) are combined, in the organizational form of work 2C+0A. It was established that the diameter of the felled tree, the slope of the terrain and the composition of the stand have the highest impact on the damage to the remaining trees in felling and wood assortment processing, while damage to the regeneration is most influenced by the operator's skill. The load of two workers who handle one larger and one smaller saw is on average by 11% lower compared to the group of workers who handle two saws of higher power, so from an ergonomic point of view (as well as in terms of fuel consumption and lubricants), the combination of a larger and a smaller saw is more favourable
Conservation of forest genetic resources in protected areas in Serbia
No full textU Republici Srbiji je zakonom defi nisano sedam različitih tipova zaštićenih područja, koja predstavljaju vid in situ konzervacije. Ukupno je izdvojeno 471 zaštićeno područje, na površini od
707.992 hа. Imajući u vidu da šumski ekosistemi, najčešće, zauzimaju veliku površinu u zaštićenim područjima i da su često ugroženi, usled delovanja različitih abiotičkih i biotičkih faktora,
konzervacija šumskih genetičkih resursa može se smatrati važnom aktivnošću u svim zaštićenim
područjima. U radu su prikazane aktivnosti na identifi kaciji retkih, ugroženih, reliktnih, endemičnih i ranjivih drvenastih vrsta i predlogu mera za njihovu konzervaciju, u različitim tipovima zaštićenih područja. Konkretni rezultati primene in situ i/ili ex situ mera konzervacije genofonda različitih šumskih drvenastih vrsta već su vidlјivi u nekima od njih, dok se u drugima implementacija
predloženih mera planira u budućnosti. Prikazan je deo rezultata sprovedenih istraživanja u jednom nacionalnom parku („Kopaonik“), jednom spomeniku prirode („Šuma Košutnjak“) i dva predela izuzetnih odlika („Veliko ratno ostrvo“ i „Kosmaj“). Kao ciljne vrste, koje su uključene u program konzervacije šumskih genetičkih resursa, izdvojene su šumske voćkarice, autohtoni hrastovi i druge retke, reliktne, endemične vrste, kao što su: planinski javor, planinski brest, poljski brest,
vez, crna topola, crni grab, mleč, tisa, itd. Predloženo je izdvajanje konzervacionih jedinica u svim
istraživanim zaštićenim područjima i realizovane su različite aktivnosti na utvrđivanju varijabilnosti raspoloživog genofonda, primenom morfoloških i/Ili molekularnih markera. Ex situ konzervacija je primenjena osnivanjem generativnih testova potomstva (divlja kruška, divlja trešnja, vez,
medunac, kitnjak, lužnjak, poljski jasen) i klonskih testova (crna topola, poljski brest) u rasadniku
Šumarskog fakulteta, Univerziteta u Beogradu, kao i osnivanjem poljskih banki gena crne topole
na Velikom ratnom ostrvu. Aktivnosti na konzervaciji i monitoringu šumskih genetičkih resursa
potrebno je nastaviti, ali i realizovati u drugim zaštićenim područjima u kojima se nalaze retke i
ugrožene drvenaste vrst
Floristic and ecological analysis of black pine forests (Pinus nigra arn.) on Western Balkan serpentinites
No full textBlack pine forests of the Western Balkans constitute a significant complex of azonally and
orographically–edaphycally conditioned forests on the ophiolitic massifs in Bosnia and
Herzegovina (B&H), Serbia, North Macedonia and Albania. They mainly exist on series of
soils on serpentinites - from eutric humus-siliceous to brown soil and pseudogley. In terms of
floristic composition, these forests exhibit great similarities, but also significant differences.
Forests of black pine on the territory of B&H, which belongs to Illyrian floral province, grow
in humid conditions with higher precipitation compared to other countries in the region,
which results in larger numbers of mesophillic species. Black pine forests in Serbia belong to
transitional Illyrian-Moesian and Moesian province and grow in continental climate with
lower precipitation, which tends to further decline towards the East, hence the black pine
forests in Central Serbia are more xerophillic with larger presence of subMediterranean species. North Macedonia has even lower precipitation and more prominent
influence of Moesian province and Aegean Sea, which results in species from those areas
being dominant, while Illyrian species are absent. Black pine forests in Albania belong to the
Mediterranean climate, however, in the mountain zone some climatic parameters tend to
become more continental. From the ecological point of view, the Albanian black pine
communities are in an intermediate position between the typical Mediterranean litoral pines
and European or continental ones. Within the natural distribution range, species composition
of black pine forests on serpentinite strongly reflects a west-east biogeographical division
related to climatic difference