The paper presents the analysis of possible potentials for the production of forest biomass in Serbia taking into consideration the condition of forests, present organizational and technical ...capacities as well as the needs and situation on the firewood market. Starting point for the estimation of production potentials for forest biomass is the condition of forests which is analyzed based on the available planning documents on all levels. Potentials for biomass production and use refer to initial periods in the production and use of forest biomass in Serbia.
Interpopulation and intrapopulation variability of three morphological needle traits (length, width and thickness) was investigated in 16 natural silver fir populations in the Balkan Peninsula. The ...populations represent refugial areas of silver fir (
Abies alba
Mill.). This paper aims to provide a comprehensive analysis of the influence of climatic factors (mean annual temperature, number of days with temperatures < 0, > 5, < 18, > 18oC, Hargreaves climatic moisture deficit and De Martonne aridity index, on the pattern of morphological needle traits within each population. Populations showed variation in the analyzed morphological needle traits, which could not be clearly defined by any of the analyzed climatic factors. The De Martonne aridity index and Hargreaves climatic moisture deficit had the greatest impact on the trait values, whereas the mean annual precipitation had the lowest. Evolutionary ecology research of the silver fir needle morphology is a valuable contribution to the comprehention of the present genetic variability as a prerequisite for adaptation to the rapid climate change and conservation of the species area in the Balkan Peninsula region.
Interpopulacijska i intrapopulacijska varijabilnost triju morfoloških osobina iglica (dužina, širina i debljina) istraživana je u 16 prirodnih populacija jele na Balkanskom poluotoku. Populacije predstavljaju refugijalna područja jele (
Abies alba
Mill.). Ovaj rad ima za cilj pružiti opsežnu analizu utjecaja klimatskih čimbenika (srednja godišnja temperatura, broj dana s temperaturama < 0, > 5, < 18, > 18°C, Hargreavesov klimatski deficit vlage i De Martonneov indeks aridnosti) na obrazac morfoloških obilježja iglica unutar svake populacije. Populacije su pokazale varijacije u analiziranim morfološkim obilježjima iglica koje se nisu mogle jasno definirati niti jednim od analiziranih klimatskih čimbenika. Najveći utjecaj na vrijednosti obilježja imao je klimatski deficit vlage po Hargreavesu, a zatim najniže vrijednosti srednje godišnje količine oborina. Evolucijska ekološka istraživanja morfologije iglica jele vrijedan su doprinos razumijevanju sadašnje genetske varijabilnosti kao preduvjeta za prilagodbu na brze klimatske promjene i očuvanje vrste na području Balkanskog poluotoka.
Predmet istraživanja u ovoj disertaciji predstavljaju tržište drveta i s njimpovezane ekonomske aktivnosti u drvnom sektoru Srbije. U cilju utvrđivanja ikvantifikovanja značaja društvenih faktora i ...njihovog doprinosa razvoju drvnog sektora,izabrani su indikatori kojima se ovaj značaj može numerički iskazati. Analiza odabranihindikatora sprovedena je sa ciljem da doprinese jasnijem i ekonomski merljivijemsagledavanju društvene uloge i značaja drvnog sektora u Srbiji. Sadašnje stanje drvnog sektora i njegov socio-ekonomski značaj rezultat jeuticaja mnogih činilaca. Tranzicioni procesi u Srbiji koji su započeli 90-ih godina XXveka doveli su do značajnih promena u drvnom sektoru. Promene su se odvijale upravcu državne centralizacije upravljanja šumskim resursima i privatizacije idefragmentacije poslova na korišćenju šuma i preradi drveta. Procesi privatizacije i izgradnje novih fabrika za preradu drveta bili supodstaknuti odgovarajućom ponudom drvne sirovine. Prosečna proizvodnjaindustrijskog drveta u periodu 2000. do 2012. godine iznosila je 0,96 milionam3, što jeimalo značajan pozitivan uticaj na razvoj drvnog sektora. Broj preduzeća u preradi drveta, posebno malih preduzeća, u 2011. godini bio jeizuzetno visok. Evidentirano je čak 1.855 aktivnih preduzeća i preduzetnika, od čega1.827 pripada kategoriji preduzeća koja imaju manje od 50 zaposlenih. U isto vreme,poslove gazdovanja šumama obavljalo je 12 preduzeća. Ukupan broj direktnozaposlenih i samo zaposlenih u drvnom sektoru je preko 31.000 radnika, od čega je18.293 direktno zaposlenih. Najznačajnije promene u odnosu na broj zaposlenih udrvnom sektoru Srbije odnose se na „pomeranje” radne snage ka ekonomskirazvijenijim područjima, pre svega ka Beogradu i Vojvodini. Analizom tokova prometadrveta takođe je uočena pojava premeštanja fabrika za preradu drveta ka ekonomskirazvijenijim delovima zemlje, što je dovelo do teritorijalne neusklađenosti preradnihkapaciteta i šumskih resursa. Kao posledica ovoga, u području „Južna i Istočna Srbija”,koje obuhvata 46% od ukupne površine šuma Srbije, zaposleno je svega 21,0% radnikaiz oblasti prerade drveta i proizvoda od drveta. Na drugoj strani, na području Vojvodinei Beograda zaposleno je 43,7% radnika. Trendovi izvoza i uvoza u drvnom sektoru su pozitivni. Kao rezultat potražnje iposlovnih aktivnosti drvnog sektora, izvoz proizvoda od drveta beležio je rast i u 2012.godini dostigao vrednost od 183,8 miliona €. Pozitivan bilans u odnosu na uvozproizvoda od drveta prvi put je zabeležen 2011. godine, od svega 2 miliona €, ali već unarednoj godini dostigao je 19,5 miliona€. Analiza dosadašnjih trendova, kao i razvojpotrošnje u zemljama UNECE regiona, ukazuju da bi izvoz proizvoda od drveta i daljemogao da ima pozitivan rast. Savremena primena biomase za energetske potrebe takođemože uticati na dalji rast proizvodnje i izvoza. Međutim, struktura izvoza ukazuje nanizak stepen razvijenosti finalne prerade drveta i proizvodnje nameštaja od masivnogdrveta, čime se na direktan način smanjuju potencijali za zapošljavanje i umanjujeproduktivnost korišćenja šumskih resursa.Analiza lanca vrednosti pokazala je značaj i zastupljenost pojedinih faza proizvodnje kroz stvaranje dodate vrednosti i zapošljavanje radnika. U posmatranom preduzeću, učešće tehničke oblovine u vrednosti gotovog proizvoda iznosilo je svega 13,3%. Istovremeno, sve poslovne aktivnosti koje obuhvata drvni sektor učestvovale su sa 33,8%. Preostala dodata vrednost od 66,2% nastala je u procesu izrade gotovih proizvoda i njihovog transporta do krajnjeg kupca na tržištu EU. Takođe, utvrđeno je da se vrednost oble tehničke građe njenom preradom do finalnog proizvoda može povećati za 7,5 puta.Pored svih problema, doprinos drvnog sektora ukupnoj ekonomiji Srbije nije zanemariv. Obračunom koji je izvršen na osnovu realnih podataka ustanovljeno je da učešće drvnog sektora u ukupnom bruto domaćem prihodu zemlje iznosi 0,64%. Doprinos drvnog sektora javnim prihodima u 2011. godini iznosio je 95,5 miliona€ i bio je 6,7 puta veći od državnih izdvajanja za potrebe razvoja sektora.
The paper presents research results of the current situation in the area of certification of forests and wood products in Serbia in the context of new European Union legislation referring to the ...placement of wood and wood products on this market. The objective of the research was to observe the situation, phases which Serbia implemented in the process of forest and wood products certification until now, as well as the problems and challenges the companies in this process face. Based on research results, future development of the market of certified wood products in Serbia was assessed and the proposal of measures which should be realized in order for Serbia to become a country whose companies will be ready for the moment when provisions and measures of the new EU legislation become effective was given. The selection of the abovementioned objective was conditioned by the fact that from January 1st, 2013 new legislation takes effect, with significantly stricter terms for the placement of wood and wood products from other countries on this market. One of the conditions which will have to be fulfilled by the companies wishing to export their products on this market refers to proving their origin. Since the EU is the most significant market for wood products exported from Serbia, fulfillment of the stated and other terms from the new EU legislation is of great importance to Serbian companies. Until the beginning of September 2010, only 387,000 ha were certified, namely 17.2; of the total area under forests. In the same period, only 33 wood processing companies in Serbia possessed CoC certificates for their products. Such a small number of companies possessing certificates for their wood products compared to competitive neighboring countries can represent a serious limitation in achieving their satisfactory competitiveness on the EU market in the following period.
The objective of this study is to assess drivers and barriers to primary forest fuel (PFF) supply in the wide-stretched South East Europe (SEE) countries and to develop strategies to improve PFF ...supply involving dozens of stakeholders from different SEE countries. SWOT (strengths, weaknesses, opportunities and threats) analyses were used to evaluate country supply chains. Based on those a regional SWOT analysis was compiled and strategies were developed and evaluated in a participative decision process. Results show that strategies for increasing biomass utilisation are of high relevance in all participating countries. Additionally, strategies for knowledge dissemination are also important. The evaluated regional strategies for the forest fuel sector examined have great potential to improve cooperation, increase efficiency and strengthen competitiveness of PFF based bioenergy production.
•Drivers and barriers to forest fuel supply in South East Europe were assessed.•A regional Meta-SWOT analysis was compiled.•Strategies were developed and evaluated in a participative decision process.•Strategies for increasing forest biomass utilisation are of high relevance.•Strategies show great potential to improve competitiveness of bioenergy production.
We demonstrate transitional dimensionality of discrete diffraction in radial-elliptical photonic lattices. Varying the order, characteristic structure size, and ellipticity of the Mathieu beams used ...for the photonic lattices generation, we control the shape of discrete diffraction distribution over the combination of the radial direction with the circular, elliptic, or hyperbolic. We also investigate the transition from one-dimensional to two-dimensional discrete diffraction by varying the input probe beam position. The most pronounced discrete diffraction is observed along the crystal anisotropy direction.
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