Omorika Digital repository of the Faculty of Forestry, University of Belgrad
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Forestry products as renewable energy sources
No full textU ovom poglavlju prikazanoje stanjeobnovljivih izvora energije u svijetu i Republici Srpskoj, sa posebnim osvrtom na drvnu biomasu. Posebno je apostrofiran značaj korišćenja drvne biomase u kontekstu smanjenja emisije štetnih gasova u atmosferu. Na bazi analize podataka iz izvještaja FAOSTAT,prikazani su proizvodnja i potrošnja biogoriva na svjetskom i evropskom nivou. U XXIvijeku potrošnja energije iz obnovljivih izvora porasla je za 38,5%. Opšti zaključak je da proizvodnja i potrošnja biogoriva u svijetu rastu veoma brzo, a najveće povećanje ostvareno je u evropskim zemljama, posebno zemljama EU. U ukupnoj proizvodnji energije iz biomase,najviše učestvuje drvna biomasa. Proizvodnja energije iz poljoprivrednih ostataka veoma malo je zastupljena u odnosu na potencijal. Većina zemalja EU ispunila je planirane kvote potrošnje obnovljive energije do 2020. godine. Plan EU je da do 2030. godine ostvari najmanje 40% smanjenja emisije gasova sa efektom staklene bašte u odnosu na nivo iz 1990. godine, kao i da učešće obnovljive energije poveća najmanje za 27% i isto tolikoostvari poboljšanje energetske efikasnosti. U Republici Srpskoj drvna biomasa je značajan energetski resurs. U posljednjih 20 godina izgrađen je veliki broj postrojenja. Za proizvodnju energije koristi se ogrevno drvo i drvni ostatak iz pilanske prerade drveta, dok je učešće drvnog ostatka poslije sječe minimalno zastupljeno. Potrebno je znatno više aktivnosti usmjeriti na korišćenje drvnog ostatka poslije sječe, jer se u šumama nalaze velike količine realno dostupnog drvnog materijala. U dijelu koji se odnosi na istraživanja u ovoj oblasti kratko su prikazani rezultati dosadašnjih istraživanja i budući pravci razvoja. U prethodnom periodu istraživanisu različiti aspekti (ekološki, tehničko-tehnološki, ekonomski, socijalnii dr.) korišćenja drvnebiomase za energiju. Korišćenje sirovine, bez obzira o kojoj kategoriji drveta se radi, može štetiti ekosistemu, ukoliko je prepušteno stihijskom korišćenju.Pozitivne strane racionalnog korišćenja drvne biomase znatno su veće od opasnosti koje se mogu javiti po šumski ekosistem. Još od 70-ih godina prošlog vijeka aktivno se radi na razvoju tehnike i tehnologije na poslovima korišćenja drvne biomase. U razvoju je učestvovao veliki broj naučnih institucija, a rezultati se ogledaju u povećanju polja primjenljivosti sredstava rada, unapređenjuergonomskih karakteristikai obezbjeđenju veće ekološke prihvatljivosti. Kada je u pitanju tržište drvnih sortimenata u Republici Srpskoj, skoro cjelokupna drvna masa oblog drveta ostaje na domaćem tržištu. Poluproizvodi i finalni proizvodi distribuiraju se na svjetsko tržište. EU je najveći uvoznik proizvoda za energetsku upotrebu, kao što su pelet, briket i dr. Velika tržišta su Italija, Njemačka, Velika Britanija itd.Prema svim procjenama,proizvodnja i potrošnja drvne biomase će se i dalje povećavati. Potencijali drvne biomase na svjetskom nivou znatno su veći od trenutne potrošnje. Imajući u vidu rast broja stanovnika u svijetu i razvoj industrijskih kapaciteta, potrebno je više raditi na stvaranju uslova za veće korišćenje ove sirovine, uz maksimalne mjere kontrole
Autochthonous species and ecological restoration of the habitats of the coastal zone of Lake Palić and Lake Ludaš
No full textRezultati prikazani u okviru ovog rada deo su podataka Projekta
„Zaštita biodiverziteta i voda jezera Palić i jezera Ludaš“- Izgradnja
zaštitnih pojaseva oko jezera Palić i Ludaš [1, 2]. Projekat je imao za cilj
uspostavljanje pojasa zelenila kao tampon zone oko jezera (oko 10 km
za Palićko jezero, a oko 14 km za Ludaško jezero) što treba da doprinese
smanjenju unosa polutanata vetrom, površinskim oticanjem i smanjenju
uticaja od direktnih poljoprivrednih aktivnosti u obalnoj zoni [3]. Širina
bafer zone koja je definisana planovima detaljne regulacije [4, 5, 6]
varira između 5 i 30 m, sa srednjom širinom od 20 m, čineći površinu od
oko 48 ha novog obalnog pojasa koji je uspostavljen u periodu trajanja
projekta 2018-2021. godina
Site conditions and floristic composition of montane beech forest with maples (Asperulo odoratae - fagetum moesiacae subass. aceretosum B. Jovanović 1973) on limestone of Očka gora, Zlatibor mountain - Serbia
No full textZlatibor je dominantno izgrađen od ultramafita. Međutim, u severnom delu, na planinskoj visoravni Gruda, nalazi se krečnjački masiv Očka gora, koji je sa istočne, severne i zapadne strane u tektonskom kontaktu sa serpentinitima, dok je sa južne tektonsko-erozionom granicom odvojen od metamorfisane dijabaz-rožnačke formacije. Na krečnjacima Očke gore zadržale su se šume bukve, dok se na drugim matičnim supstratima, koji je okružuju, pojavljuju samo sporadično. Opstanak bukovih šuma na Očkoj gori vezan je za morfologiju terena, jer su na površini zastupljeni krečnjački blokovi metarskih dimenzija koji nisu bili pogodni za poljoprivrednu proizvodnju. Šume bukve na Očkoj gori pripadaju u asocijaciju planinske šume bukve sa javorima (Asperulo odoratae - Fagetum moesiacae subass. aceretosum B. Jovanović 1973). Ove šume su prema biološkom spektru hemikriptsko-fanerofitske. Po horološkom spektru preovlađuju vrste srednjeevropskog areal tipa. Po ekološkim spektrima: prema vlažnosti navedena zajednica je submezofilna, prema reakciji zemljišta neutrofilna, prema svetlosti polusciofilna do sciofilna i prema toploti mezotermna
Production portfolio analysis of companies form the field of forestry - case study
No full textU radu je, kroz studiju slučaja preduzeća iz oblasti šumarstva, izvršena analiza proizvodnog portfolija i definisana pozicija svakog proizvoda u okviru BCG (rast/ učešće) matrice. Takođe, na osnovu sprovedene SWOT analize identifikovane su jake i slabe strane preduzeća, kao i šanse i pretnje iz okruženja. Cilj rada je identifikovanje najboljeg načina korišćenja finansijskih sredstava i definisanja potrebe za uvođenjem novih proizvoda, u svrhu procene potencijala i tržišnih mogućnosti preduzeća „Gradina Sistem” d.o.o. iz Temerina. Svrha rada je da se na osnovu utvrđenih pozicija pojedinih proizvoda definišu pravci (pre)usmeravanja finansijskih sredstava ka održivijim i profitabilnijim. Predmet istraživanja je preduzeće „Gradina Sistem” d.o.o iz Temerina, njegov dosadašnji sistem poslovanja i proizvodni portfolio, koji je u najvećoj meri usmeren na: drvene patose, palete i gajbice od topole
Comparative analysis of the lawns structure along Belgrade city roads
No full textIstraživanja obuhvataju uporednu analizu structure i florističkog sastava različitih tipova travnjaka duž saobraćajnica Beograda (travne površine kružnih tokova, razdelnih traka, površina u neposrednoj blizini saobraćajnica i travne površine saobraćajnica prvog reda). U analizama su korišćeni rezultati florističkih istraživanja iz 2002. godine, kao i rezultati terenskog istraživanja sprovedenog tokom 2019. godine. Na istraženim travnim površinama duž Beogradskih saobraćajnica evidentirano je ukupno 114 biljnih vrsta, među kojima najveći broj pripada kategoriji korovskih vrsta. Zakorovljenost travnjaka saobraćajnica posledica je specifičnih uslova sredine koji vladaju na ovim tipovima zelenih površina i pogoduju naseljavanju i širenju korovskih vrsta, ali i slabijeg intenziteta negovanja i održavanja. Taksonomska analiza je pokazala da je nakon 17 godina došlo do smanjenja broja familija i rodova na istraživanom području. Evidentirana je apsolutna dominacija biljaka iz grupe hemikriptofita u oba istraživana perioda. Rezultati istraživanja služe za davanja smernica i preporuka za unapređenje stanja i strukture travnjaka duž Beogradskih saobraćajnica. Takođe, oni čine i osnovu za budući izbor adekvatnih vrsta trava za zasnivanje novih kao i reparaciju postojećih travnjaka, odnosno u širem smislu za održivo upravljanje zelenim površinama duž gradskih saobraćajnica.The research includes a comparative analysis of the structure and floristic composition of different types of lawns along Belgrade roads (grass areas of roundabouts, dividing strips, areas near roads and grass areas of first order roads), their floristic composition, as well as determining changes over a period of 17 years. The analyses are based on the results of floristic research from 2002, as well as the results of field research conducted during 2019. A total of 114 plant species were recorded on the studied lawns along Belgrade roads, among which the highest proportion belongs to the category of weed species. The taxonomic analysis has shown a reduction in the recorded number of families and genera over the study period of 17 years Both studies indicate the absolute dominance of plants from the group of hemicryptophytes. The results of the research are used to provide guidelines and recommendations for improving the condition and structure of lawns along Belgrade roads. Also, they provide the basis for the future selection of adequate types of grass for the establishment of new lawns, as well as the repair of the existing ones, i.e. for the sustainable management of green spaces along city roads
Establishing Correlation between Cruise Ship Activities and Ambient PM Concentrations in the Kotor Bay Area Using a Low-Cost Sensor Network
No full textThe analysis of cruise ships is focusing on port areas where they may represent a significant source of anthropogenic emissions. In order to determine the correlation between cruise ship activities (hoteling and maneuvering) in ports with the ambient concentration of pollutants associated with marine diesel fuel combustion, the low-cost sensors are finding their market share due to lower prices compared to the referent ones. In this study, a network of four low-cost PM sensors was used to determine the correlation between ambient PM2.5 and PM10 mass concentrations with cruise ship activities in the Kotor Bay area during 27 days in the peak summer season, with a 10-min resolution. Recorded data and the Openair model were used to investigate the potential relationship between cruise ship operations and temporal fluctuations in PM concentrations in the ambient air. Additionally, an Tier 3 methodology developed through the European Monitoring and Evaluation Programme of the European Environmental Agency (EMEP/EEA) was applied in order to estimate the total cruise ship PM emissions. The study has shown that weather conditions play a significant role in local PM concentrations, so that, with predominant ENE wind directions, the west side of the Bay experienced on average higher concentrations of both PM2.5 and PM10. Rain precipitation and higher winds tend to decrease rapidly ambient PM concentrations. Higher PM levels are associated mainly with lower wind speeds and the inflows from neighboring berths/anchorages. During the maneuvering (arrival and departure) of cruise ships, higher spikes in PM values were detected, being more visible for PM10 than PM2.5. A significant correlation between daily average PM concentrations and cruise ships’ daily estimated PM emission was not found. As a result, higher temporal resolution demonstrated a stronger correlation
Comparative analysis of the influence of climate factors on the radial growth of autochthonous pine species ( pinus spp.) In central Bosnia and Herzegovina
No full textIn central Bosnia and Herzegovina, in the Zavidovici-Teslic area, the study of the radial growth of Austrian and Scots pine (autochthonous pine species) trees was conducted using the dendrochronological method in order to identify the differences between the species in terms of the influence of climatic variables on the tree ring formation. Trees were sampled in five experimental areas or five sites. The first site had a Scots pine stand, while the second had an Austrian pine stand, and the other three sites had mixed stands of Scots and Austrian pine. Cross-dating was conducted using visual on-screen techniques of CDendro software and statistical methods using Cofecha software. The tree ring series were standardized using the Arstan program and cubic smoothing spline. It produced Scots pine regional chronology, 145 years long (1870-2014), and Austrian pine regional chronology, 180 years long (1835-2014). Correlation analysis of the relationship between the index of tree-ring width and precipitation and temperature in the characteristic periods of the year showed a negative effect of temperature (except in winter months) and a positive effect of precipitation on the tree ring formation. The statistically significant dependence of the tree-ring width index on the SPEI indices indicates a significant impact of moisture deficiency on the tree ring formation in the period from June to August (r = 0.33 in June, r = 0.45 in July and r = 0.47 in August) for Scots pine and in the period from June to September (r = 0.36 in June, r = 0.43 in July, r = 0.47 in August and r = 0.30 in September) for Austrian pine. The analysis of the relationship between climatic parameters and the chronologies of Scots and Austrian pine shows similar relationships between radial growth and climate but the influence of climate is somewhat more pronounced in Austrian pine. In the study area, the radial growth of both tree species is significantly determined by climate conditions. In other words, the chronology of these species has a good climatic signal, especially the drought signal in the summer months
Application of retaining structures in rehabilitation of landslide on Stolice - Krupanj regional road
No full textNa pojavu klizišta mogu uticati mnogi faktori: promenljivi klimatski uslovi; velika količina padavina u kratkom periodu; složenost strukture terena; opterećenja od saobraćaja, itd. Rad se bavi problemom sanacije klizišta na regionalnom putu Stolice - Krupanj, koje je nastalo usled opterećenja od vozila i zasićenja zemljišta vodom. Tehničke mere koje su primenjene za sanaciju klizišta su: betonski potporni zid i potporna konstrukcija od tla i geomreže. Na osnovu podataka o zemljištu iz laboratorijskih ispitivanja izvršene su provere stabilnosti kosina pre i posle primenjenih mera sanacije u programu GEO5, dok je stabilnost betonskog zida ispitivana analitičkim proračunom faktora sigurnosti na prevrtanje i horizontalno pomeranje. Obe tehničke mere, zadatih fizičko mehaničkih karakteristika, povećale su stabilnost padine.Landslides can be triggered by different factors including changeable weather conditions, prolonged heavy rains, complex terrain, traffic loads, etc. This paper deals with the problem of landslide rehabilitation on the Stolice-Krupanj regional road that resulted from vehicle loads and soil saturated with water. The technical measures used in the rehabilitation of the landslide included a concrete retaining wall and a geogrid-reinforced soil structure. Based on data related to soil obtained from laboratory tests, slope stability before and after applying rehabilitation measures was tested in the GEO5 Geotechnical software. The stability of the concrete wall was examined analytically by calculating the factors of safety against toppling and horizontal displacement. Both technical measures of given physicalmechanical properties increased the stability of the slope
Factors Affecting Seed Germination of the Invasive Species Symphyotrichum lanceolatum and Their Implication for Invasion Success
No full textInvasive species Symphyotrichum lanceolatum (Willd.) G. L. Nesom is spreading uncontrollably along wet habitats as well as in disturbed ecosystems. All those habitats function as corridors that facilitate seed dispersal. One way to prevent the spread of invasive species is to know their reproductive ecology. The present study evaluates the potential for generative reproduction of S. lanceolatum and determines how different temperatures, amounts of nutrients, and light regimes, affect seed germination. Seeds collected from 13 natural populations were germinated at four fluctuating temperature regimes (15/6, 20/10, 30/15, and 35/20 degrees C). To test the influence of nitrate on seed germination, two KNO3 concentrations were used (5 mM and 50 mM solution). For each treatment, three replicates of 30 seeds were placed in complete darkness or a 14 h photoperiod. The results showed that the germination increased with increasing temperature. The optimal temperature regimes were 30/15 degrees C and 35/20 degrees C with approximately 88% germination. The overall effect of KNO3 on germination was positive. The concentration of 50 mM KNO3 had a less stimulating effect compared to 5 mM KNO3. Seeds showed sensitivity to lack of light during germination but were able to germinate in a significant percentage in such conditions. Considering that S. lanceolatum often occurs in disturbed sites, these results suggest that seed reaction to alternating temperature, nutrients concentration, and light can be determining factors that affect seed germination of this species and, thus, its spread
Upravljanje klimatskim promenama u šumarstvu i povezanim sektorima: stavovi ispitanika u odabranim šumskim područjima i nacionalnim parkovima u Srbiji
No full textEffectively combating climate change involves recognition of its negative
environmental, economic and social impacts. Climate change governance
requires the participation of stakeholders from different sectors, and the
alignment of their interest and influence in the decision-making
process. This paper aims to determine the attitudes of respondents towards
the existence of climate change and assess their negative impact on
forestry, forest ecosystems and protected areas. In addition, the goal is to
identify differences in the assessment of interest and influence between
stakeholders in climate change governance in selected forest regions and
national parks in Serbia. Primary data were collected through interviews (103
in total), in the period from March 2017 to July 2019, with representatives
of organizations from the public and civil sector, who deal with issues of
forestry, nature conservation and climate change. Respondents believe that
climate changes have a negative environmental, social and economic impact on
forestry, forest ecosystems and protected areas. It was found that there are
differences in interest and influence in climate change governance between
stakeholders, regardless of sectoral affiliation. In addition, stakeholder
influence assessments were found to be lower than interest in climate change
governance. Opportunities for enhancing stakeholder interest and influence in
climate change governance have been proposed