12 research outputs found

    Application of Generalized Taper Model of Norway Spruce Tree in Forestry Practice

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    U radu je prikazan jedinstveni model oblika debla smreke, razvijen primjenom modificirane Brinkove funkcije, za područje Bosne i zapadne Srbije. Cilj istraživanja je izvrÅ”iti prilagođavanje jedinstvenih modela (Model 1 i Model 2) oblika debla prikazanih u radu Matovića, i dr.(2007) za jednostavnu praktičnu primjenu u Å”umarstvu. Jedinstveni model dobiven u ovome radu (Model 3) pokazuje neÅ”to manju preciznost procjene promjera duž debla i volumena stabla od jedinstvenih Modela 1 i 2, ali je joÅ” uvijek dovoljno precizan, pa se uspjeÅ”no može rabiti u Å”umarskoj praksi. U radu je izvrÅ”eno i uspoređenje jedinstvenih modela oblika debla s klasičnim dvoulaznim volumnim tablicama. Model 3 ima značajnu praktičnu primjenu i može se koristiti za procjenu volumena cijelog ili dijelova debla, promjera na bilo kojemu dijelu debla i neposredno visina stabla na kojima se nalaze karakteristični (traženi) promjeri.By applying modified Brinkā€™s function, this paper presents the unique generalized taper model of Norway spruce tree, developed for the area of Bosnia and west Serbia. The objective of this research is adapt generalized taper models (Models 1 and 2) for trees presented in the paper Matović, et al. (2007), for practical use in forestry. The significant quality of the modified Brinkā€™s function is the correlation of the characteristics of individual trees and stands and the function parameters, so in this way generalized taper models can be calculated for the use in a definite geographic region. The study of Norway spruce taper is based on the data collected from 86 even-aged stands in the region of Bosnia and west Serbia, which is adjacent to Bosnia. The total number of model trees is 156, and the number of data pairs (diameter-height) is 2028. The original parameters i, p and q of the modified Brinkā€™s function were first calculated for all model trees by the optimisation method - equations (1). By applying the multiple regression method, a link has been established between original values of parameters i, p and q, and characteristics of individual trees (diameter at breast height and tree height), i.e. Model 3 has been obtained. Model 3 is consisted of three functions used for determining the parameters of generalized taper model i, p and q. Unknown parameters of the three functions a1, a2, a3,...,.a15 are determined on the basis of available data, by applying multiple regression ā€“ equations (2), (3) and (4). In order to test the estimation of taper volume, on the material used for the development of generalized taper models of spruce trees by applying multiple regression, dual input volume tables were created. For that purpose NƤslund and Schumacher-Hall functions were used ā€“ equations (6) and (7). This research confirms that Model 3 shows less accuracy in estimating the diameter along the taper and volume than Models 1 and 2, which besides using the diameter at breast height and tree height, also require using the stand quadratic mean diameter. However, such difference, from the aspect of practical use, is not important, so Model 3 that applies only the diameter at breast height and tree height (in fact, reduced to the level of dual input volume tables) can be successfully used in forestry practice. Obtained Model 3 is the superior substitute for conventional dual input volume tables, because besides the total volume it enables the volume estimation for particular parts of the standing tree, and also estimation of the diameter along the taper. Model 3 indirectly enables the calculation of tree heights with some diameters characteristic for forestry practice. Model 3, with all above mentioned practical possibilities, can be very simply used by applying one EXCEL application. Because of the dimensions of trees used for Model 3 design, it can be reliably used in practice for Norway spruce trees with diameters at breast height of 10 to 60 cm and height of 6 to 37 m

    Quality and Assortment Structure of Beech High Forests in Serbia

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    The paper presents research results on quality and assortment structure of uneven-agedbeech high forests in Central Serbia. Eleven representative stands of submontane beech forest(Fagenion moesiacae submontanum B. Jov. 1976 ) and montane beech forest (Fagenion moesiacaemontanum B. Jov. 1976) were selected. Their altitude ranges from 450 m to 1350 m. Site class rangesfrom I/II to III/IV, canopy closure from 0.7 to 0.9 and volume from 290 m3/ha to 522 m3/ha. Total areaof the stands is 241.9 ha. Sample plots of 500 m2 were established in a systematic grid of 100 x 100 m.From silvicultural aspect, 16% of the standing volume (384 m3/ha) is class one, 39% is class two and45% is class three. From the aspect of forest utilization 37% of the volume is class one, 34% is classtwo, 19% is class three, and 10% is class four. In the assortment structure of the average stand volume,industrial wood accounts for 42%, cordwood 48% and waste 10%. It has been concluded that beechhigh forests in Serbia have unfavourable quality and assortment structure. This situation should beimproved in future by taking adequate management measures

    Usporedba strukture sastojina gospodarenih i praŔumskih bukovih Ŕuma Srbije

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    This study presents results of the comparison of structural and production characteristics of managed and virgin European beech forests in Serbia. Five managed and three virgin European beech stands were studied. The aim of this research was to determine the impact of the previous forest management on the structural diversity and production characteristics of managed European beech high forests in Serbia. The observed stands are located in the mountainous range of 400 to 1200 meters above sea level in the areas with the most productive beech forests in Serbia. Structural characteristics were compared using the following parameters: Height curves, Diameter distribution, Gini index, Coefficient of variation, Slenderness coefficient and maximum dimensions of standing living and dead trees. Stand density and productive characteristics were studied using the following forest estimation elements: number of trees, basal area, volume, biomass, carbon stock, stand quadratic mean diameter, Loreyā€™s mean height and volume of dead wood. The greatest differences were found in the dimensions of the largest trees in managed and virgin beech forests (diameters at breast height and heights). Certain differences were found in the shape of Height curves and Diameter distribution and in the values of Slenderness coefficient. However, the Gini index and the Coefficient of variation show that these managed beech forests in Serbia substantially preserve the primeval structural diversity. The differences in the average value of most forest estimation elements of managed beech high forests in Serbia compared to virgin beech forests are statistically significant, which tells us that the previous management had a significant impact on the changes in the production characteristics of these forests in Serbia.U radu se prikazuju rezultati usporedbe strukturnih i proizvodnih karakteristika bukovih sastojina gospodarskog iĀ  praÅ”umskog tipa u Srbiji. Istraživano je pet sastojina gospodarskogĀ  i tri sastojine praÅ”umskog tipa. Cilj ovog istražiĀ­vaĀ­nja bio je utvrditi utjecaj prethodnog gospodarenja Å”umama na strukturnu raznolikost i proizvodne osobine visokih bukovih Å”uma u Srbiji. Istraživane sastojine nalaze se u planinskom rasponu od 400 do 1200 metara nadmorske visine u područjima gdje se nalaze najproduktivnije bukove Å”ume u Srbiji (slika 1 i tablica 1). Strukturne karakteristike usporeĀ­Ä‘eĀ­ne su pomoću sljedećih parametara: visinske krivulje, debljinska struktura, Gini indeks, koeficijent varijacije, koeficijent vitkosti i maksimalne dimenzije dubećih živih i mrtvih stabla. Sastojinsku gustoću i produktivne osobineĀ  proučavane su pomoću sljedećih procijenenih taksacijskih elemenata: broj stabala, temeljnica, volumen, biomasa, zaliha ugljika, srednji promjer po temeljnici, Lorajeva srednja visina i volumen mrtvog drveta. Najveće razlike pronađene su u dimenzijama najvećih stabala u bukovim sasatojinama gospodarskog i praÅ”umskog tipa (tablica 4). Određene razlike proĀ­naĀ­Ä‘ene su u obliku visinskih krivulja i debljinskoj strukturi, i vrijednostima koeficijenta vitkosti (slike 2, 3, 4 i 5, i tablica 3).Ā  Međutim, Ginijev indeks i koeficijent varijacije pokazuju da su bukove sastojine gospodarskog tipa u Srbiji u velikoj mjeri sačuvale iskonsku strukturnu raznolikost (tablica 2 i slika 6). Razlike u prosječnim vrijednostima taksacijskih elemenata sastojina gospodarskog tipa visokih bukovih Å”umama u Srbiji u odnosu na sastojine praÅ”umskog tipa su statistički značajne, Å”to nam govori da je prethodno gospodarenje imalo značajan utjecaj na promjene u proizvodnim karakteristikama ovih Å”uma u Srbiji (tablica 5)

    Jednofazna žetva semena žutog zvezdana univerzalnim žitnim kombajnom

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    The biggest problem in seed birdsfoot trefoil harvest is pod cracking before and during harvest. At full maturity, birdsfoot trefoil pods crack easily, resulting in seed spillage and hence seed losses. The cracking pod problem significantly limits the successful production of seeds. Exploitation indices, operational performance and reliability of a used general-purpose Claas Mercator 50 combine harvester in harvesting birdsfoot trefoil seed were studied. The testing was carried out in field conditions in Western Serbia area. The losses of grain over the cutter bar and over the threshing machine were found out.Total header and thresher losses ranged from 21.28% to 23.86% at an operating speed of 2.04 km/h and 2.63 km/h, respectively. This is an expected result for the crop under increased crop moisture conditions. There was loss of operating time i.e. congestion of unharvested grain due to increased operating rate, seed moisture and straw. Time consumption for elimination of harvesting delay at a rate of 2.63 km/h was higher than at a rate of 2.04 km/h and accounted for 13.48% of the total operating time. The research also involved monitoring of intensity pod cracking during the day depending on air temperature. Birdsfoot trefoil pod opening intensity increased of starts after 11 a.m. at air temperatures over 30 0 C when 80-90% of pods crack at 17- 20% moisture.U žetvi semena žutog zvezdana najveći problem predstavlja otvaranje mahuna pre i toku žetve. U punoj zrelosti mahune žutog zvezdana lako se otvaraju i seme se prosipa Å”to dovodi do gubitaka. Problem otvaranja mahuna u značajnoj meri limitira uspeÅ”nu proizvodnju semena. Istraživani su eksplatacioni pokazatelji, kvalitet rada i pouzdanost starog univerzalnog žitnog kombajna 'Claas Mercator 50' u žetvi semena žutog zvezdana. Ispitivanje je obavljeno u poljskim uslovima Zapadne Sbije. Ustanovljeni su gubici na hederu i vrÅ”alici kombajna. Ukupni gubici hedera i vrÅ”alice na ispitivanom kombajnu iznosili su od 21,28% do 23,86% pri radnim brzinama 2,04 km/h i 2,63 km/h, Å”to se moglo i očekivati za pomenuti kombajn i ovu kulturu u uslovima povećane vlažnosti useva. Tokom rada kombajna dolazilo je do zastoja tj. zaguÅ”enja vrÅ”idbene mase, usled povećane radna brzina, vlažnosti semena i slame. UtroÅ”eno vreme za otklanjanje tehnoloÅ”kih zastoja kod radne brzine od 2,63 km/h bilo je veće nego kod brzine od 2,04 km/h i iznosilo je 13,48% od ukupnog radnog vremena. Intenzitet pucanja u toku dana zavisno od temperature je takođe bio predmet ispitivanja ovog rada. Povećani intenzitet otvaranja mahuna počinje posle 11 sati, pri temperaturi vaduha preko 30 0 C kada se otvori 80-90% mahuna vlažnosti od 17- 20%

    Estimation of Biomass in a Submontane Beech High Forest in Serbia

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    The analysed submontane beech forest (Fagenion moesiacae submontanum B. Jov. 1976) is situated in Eastern Serbia (Majdan-Kučajna, compartment 33a). Stand area is 22.7 ha. Its altitude is 410-520 m and the slope is 7ā€“28Ā°. Parent rock consists of dense limestone, and the soil is calcocambisol. The stand is uneven-aged, managed under group selection, with a volume percentage of beech is 97%. Other statistics of the stand are: site class II, canopy closure 0.9, mean diameter 39.4 cm, and Loreyā€™s mean height 31.0 m. For biomass evaluation, circular sample plots of 500 m2 size were used with the area intensity of 5%. While the aboveground biomass amounts to 337.69 tons/ha or 85.9%, belowground biomass makes 55.49 tons/ha or 14.1% of the total biomass. The proportion of timber in the aboveground biomass is 89.7%, brushwood 9.3% and leaves 1.0%. Estimation of biomass of the uneven-aged beech high forest was based on the results of investigations on European beech in Central/Western Europe

    Quality and Assortment Structure of Beech High Forests in Serbia

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    The paper presents research results on quality and assortment structure of uneven-aged beech high forests in Central Serbia. Eleven representative stands of submontane beech forest (Fagenion moesiacae submontanum B. Jov. 1976 ) and montane beech forest (Fagenion moesiacae montanum B. Jov. 1976) were selected. Their altitude ranges from 450 m to 1350 m. Site class ranges from I/II to III/IV, canopy closure from 0.7 to 0.9 and volume from 290 m3/ha to 522 m3/ha. Total area of the stands is 241.9 ha. Sample plots of 500 m2 were established in a systematic grid of 100 x 100 m. From silvicultural aspect, 16% of the standing volume (384 m3/ha) is class one, 39% is class two and 45% is class three. From the aspect of forest utilization 37% of the volume is class one, 34% is class two, 19% is class three, and 10% is class four. In the assortment structure of the average stand volume, industrial wood accounts for 42%, cordwood 48% and waste 10%. It has been concluded that beech high forests in Serbia have unfavourable quality and assortment structure. This situation should be improved in future by taking adequate management measures

    Energetski potencijal produkata rezidbe voćarskih i vinogradarskih zasada Srbije

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    Modern technologies of the fruit and wine production include implementation of the intensive plantation pruning where the accumulated considerable amounts of plant biomass residue have significant environmental and energy value. Thermal energy and the use of pruning residues as biomass are important from the point of view of environmental protection and the closed-cycle of CO2 emission and consumption. Remains of the pruning in the orchards represent a problem during the implementation of agricultural practices, so necessity for their disposal from these surfaces exists. Fossil fuel limited reserves and the environmental pollution impose the necessity of finding alternative and renewable energy resources with the environmental pollution reduction. Very important problem is to correctly define the optimal technical solutions and technologies for utilization of machine pruning of fruit trees and vines, which will increase the energy efficiency of the production. Outdated technologies, extensive production and inefficient consumption of energy in our country environment, haven't been helping in the suitable application of the collecting, preparing and using of the remains of the pruning. The prerequisite for the study of the economic and technical feasibility for the using of pruning residues (biomaterials) are the information about the quantity, the energy potential, the workmanship, the transportability, the price, the storage convenience, the preservation and the combustion. The essential starting point for this research is the annually definition of the energy potential of the pruning residues. .Savremene tehnologije voćarsko-vinogradarske proizvodnje podrazumevaju sprovođenje intenzivne rezidbe zasada gde nastaju znatne količine biljnih ostatka koji predstavljaju biomasu znatne ekoloÅ”ke i energetske vrednosti. Dobijanje toplotne energije i upotreba ostataka rezidbe kao biomase značajna je sa stanoviÅ”ta zaÅ”tite okoline, zbog zatvorenog ciklusa emisije i potroÅ”nje CO2. Ostatci rezidbe u zasadima predstavljaju problem u sprovođenju agrotehničkih mera, tako da je neophodno njihovo iznoÅ”enje sa navedenih povrÅ”ina. Ograničene rezerve fosilnih goriva i veliko zagađenje životne sredine nameću potrebu iznalaženja alternativnih i obnovljivih izvora energije koji istovremeno smanjuju ekoloÅ”ko zagađenje. Veoma aktuelni problem predstavlja definisanje optimalnih tehnologija i tehničkih reÅ”enja maÅ”ina za koriŔćenje ostataka rezidbe voćaka i vinove loze, Å”to znatno povećava energetsku efikasnost ove proizvodnje. Zastarele tehnologije, ekstenzivna proizvodnja i neracionalno raspolaganje energijom, u naÅ”im uslovima, prikupljanje, obrada, priprema i koriŔćenje biljnih ostataka nisu naÅ”li adekvatnu primenu. Preduslov za istraživanje ekonomske i tehničke opravdanosti koriŔćenja ostataka rezidbe (biomaterijala) predstavljaju podaci o količini, energetskom potencijalu, načinu obrade, transportabilnosti, ceni, pogodnosti za skladiÅ”tenje, čuvanje i sagorevanje. Najznačajnije polaziÅ”te tom istraživanju je definisanje energetskog potencijala ostataka rezidbe na godiÅ”njem nivou.

    Biological efficacy of the ecotoxically favourable insecticides and their mixture in the control of gypsy moth

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    Forest certification is one of the ways of adapting forestry to modern ideas of "sustainable management", by meeting demands of Forest Stewardship Council (FSC) standard. By joining this process, Serbia obligated to follow FSC pesticides policy. Almost all insecticides registered in Serbia and applied for control of the most dangerous outbreaking defoliating species in forests, are on the list of prohibited ones. In certificated forest ecosystems in Serbia, microbiological insecticides (active ingredient: Spores and protein-crystals of the bacterium Bacillus thuringiensis ssp. kurstaki) are most widely used pesticides for the control of one of the most important economically harmful defoliators - gypsy moths, in progragation phase, when the number of pests is relatively small. When the number is greater, it is assumed that the so-called "soft" ecotoxicologically favourable preparations Avaunt (R), Alverde (R), Coragen (R), registered for application in agriculture, but not in forestry can be used for inhibition of multiplication. Studies of biological efficacy of the aforementioned preparations and their mixtures with biological insecticide Foray (R) showed that they have preconditions for application in forest ecosystems. The high biologic efficacy, mechanism of action, resistance to water rinsing, high selectivity, and small quantities of application, anticipated a bright future for them. Since results of researches of biological efficacy of insecticides in laboratory and field conditions are statistically different, studies done in natural conditions should be favored

    MRTVO DRVO U GOSPODARENIM BUKOVIM ŠUMAMA NA PODRUČJU SRBIJE

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    Dead wood in forests of Serbia hasn`t been studied so far, although it is an important component of forest ecosystems. This paper presents results of investigating volume, biomass, and carbon stock bound in the dead wood of beech high forests. The sample includes eleven pure beech stands selected in six forest regions. They are all uneven-aged stands that have been managed for the last several decades, mostly under selection or group-selection. Their site class is I/IIā€“III/IV. The altitude ranges from 400 to 1380 m. One stand belongs to submontane (Fagetum moesiacae submontanum B. Jov. 1967) and ten to montane (Fagetum moesiacae montanum B. Jov. 1953) beech forests. A systematic sample was used to determine the presence, quantity, diameter structure of volume, and state of dead wood considering its degree of decomposition both in standing and lying position. Sample plots of 500 m2, at a distance of 100 x 100 m were used as elements of the sample. Altogether 242 sample plots were established. The volume of aboveground dead wood was determined by applying familiar dendrometric methods, while the dry biomass was calculated on the basis of its volume and wood density at different degrees of decomposition. The biomass of belowground dead wood i.e. roots of stumps and snags was obtained directly using the relevant regression equations. The quantity of the carbon bound in dead wood was calculated by multiplying dry biomass of dead wood by 0.5 coefficient. A simple and a stratified sample were used for the purposes of estimating the average and total volume, biomass, and carbon stock of dead wood. It was concluded that the average aboveground deadwood volume in all studied stands amounted to 19.24 m3 haā€“1. The aboveground biomass of dead wood was 6.06 t haā€“1 and belowground 17.34 t haā€“1, or 23.40 t haā€“1 in total. The carbon-bound stock in the total estimated dry biomass of dead wood was 11.70 t C haā€“1.U cilju rjeÅ”avanja problema energetske krize i klimatskih promjena u svijetu se pridaje veliko značenje proučavanju biomase, odnosno zalihe i kruženja ugljika u Å”umskim ekosustavima. Proučavan je najčeŔće utjecaj klimatskih promjena i načina gospodarenja na razvoj i stabilnost Å”umskih ekosustava, kao i njihov doprinos ublažavanju negativnih utjecaja klimatskih promjena na životni okoliÅ” (Cannell 1995., Lebaube et al. 2000., Joosten et al. 2004., Mund 2004., Mund and Schulze 2006., Liski et al. 2006). Mrtvo drvo je najviÅ”e proučavano u praÅ”umama, odnosno rezervatima bukovih Å”uma (Christensen et al. 2005). Uz to, proučavano je u približno prirodnim bukovim Å”umama (Beneke and Manning 2003., Mountford 2002) i u gospodarenim bukovim Å”umama (Green and Peterken 1997., Fridman and Walheim 2000., Ferguson and Archibald 2002., Mund 2004., Mund and Schulze 2006). Rađena je i komparacija karakteristika mrtvog drveta u prirodnim ā€“ negospodarenim i gospodarenim Å”umama (Andersson and Hytteborn 1991., Kirby et al. 1998). U Europi, volumen dubećeg i ležećeg mrtvog drveta u uređivanim ā€“ proizvodnim Å”umama označena je kao važan indikator za održivo gospodarenje i očuvanje biodiverziteta (MCPFE 2003). Prema tomu, mrtvo drvo je važna komponenta Å”umskih ekosustava. Međutim, u Å”umama Srbije do sada nije detaljnije proučavano. Zbog toga, cilj ovog rada bio je dobivanje pouzdanih informacija o najznačajnijim karakteristikama mrtvog drveta (volumenu, biomasi i ugljiku) u visokim gospodarenim bukovim Å”umama koje su u državnom vlasniÅ”tvu.Istraživane sastojine bukve po strukturnoj su izgrađenosti specifične, a početkom dvadesetog stoljeća bile su pretežito praÅ”ume, pa su neurednim prebornim sječama prevedene u privredne Å”ume. Radi se o izrazito raznodobnim sastojinama bukve, specifične starosne strukture. Uzorkom je obuhvaćeno jedanaest čistih sastojina bukve izabranih u Å”est Å”umskih područja (Slika 1). Jedna sastojina pripada brdskoj (Fagetum moesiacae submontanum B. Jov. 1967) a deset sastojina planinskoj Å”umi bukve (Fagetum moesiacae montanum B. Jov. 1953). Klima je umjereno kontinentalna. PovrÅ”ina sastojina je 9,8ā€“32,3 ha (ukupno 241,9 ha). Bonitet staniÅ”ta je I/IIā€“III/IV, nadmorska visina 400ā€“1380 m, prosječan nagib terena 11ā€“27Ā°, najčeŔća ekspozicija sjeverozapadna, stupanj sklopa 69ā€“94 %, srednji promjer po temeljnici 30ā€“42 cm, srednja visina po Loraju 22ā€“34 m, broj stabala 214ā€“308 po ha, temeljnica 22ā€“33 m2 haā€“1, volumen 290ā€“522 m3 haā€“1 i volumni prirast 5,0ā€“10,5 m3 haā€“1. Kvalitativna i sortimentna struktura istraživanih sastojina bukve bila je loÅ”a (Koprivica et al. 2010b).Za utvrđivanje prisutnosti, količine, debljinske strukture volumena i stanja mrtvog drveta glede stupnja raspadanja u dubećem i ležećem položaju primijenjen je sistematski uzorak. Kao elementi uzorka u sastojinama koriÅ”tene su probne plohe veličine 500 m2, raspoređene na rastojanju 100 x 100 m. Postavljene su ukupno 242 probne plohe. Volumen mrtvog drveta na probnim plohama iznad zemlje određen je po klasičnim dendrometrijskim metodama, a suha biomasa na bazi njegovog volumena i gustoće drveta pri različitom stupnju raspadanja (Marjanović et al. 2010). Biomasa mrtvog drveta ispod zemlje (korijena panjeva i suhih stabala) određena je izravno po regresijskoj jednadžbi (Wutzler et al. 2008). Sadržaj vezanog ugljika u mrtvom drvetu dobijen je množenjem suhe biomase mrtvog drveta s koeficijentom 0,5 (IPCC 2003). Za procjenu prosječnog i ukupnog volumena, biomase i zalihe ugljika primijenjen je jednostavni i stratifikacijski uzorak.Prosječan volumen živog i mrtvog drveta iznad zemlje po hektaru u sastojinama i za sve istraživane sastojine zajedno prikazan je u tablici 2. Za sastojine dobiveni su podaci nedovoljne točnosti. Međutim, podaci dobiveni za sve istraživane sastojine zajedno su dovoljno točni ā€“ pouzdani. Prosječan volumen mrtvog drveta iznad zemlje svih istraživanih sastojina bukve zajedno (p = 0,95, n-1 = 241) je 19,24 +/ā€“ 2,63 m3 haā€“1 ili 5,01 % od prosječnog volumena živog drveta (383,9 +/ā€“ 20,58 m3 haā€“1). Metodom analize varijance utvrđeno je da je razlika između sastojina, s obzirom na prosječan volumen mrtvog drveta po hektaru, statistički značajna. Volumen mrtvog drveta s obzirom na način javljanja i stupanj raspadanja prikazan je u tablici 5, a s obzirom na debljinsku strukturu volumena u tablici 6. Na osnovi jednostavnog uzorka od 242 probne plohe utvrđeno je da je raspored mrtvog drveta iznad zemlje po hektaru jako pozitivno asimetričan i jako izdužen u odnosu na normalni raspored. Koeficijent varijacije je 108 %. Relativna greÅ”ka uzorka (p = 0,95) je +/ā€“ 13,61 %. Primjenom stratifikacijskog uzorka dobivena je relativna greÅ”ka uzorka +/ā€“ 13,01 %. Na osnovi stratifikacijskog uzorka, interval povjerenja (p = 0,95, n-4 =238) za prosječan volumen mrtvog drveta je 16,74ā€“21,74 m3/ha. Prosječna suha biomasa mrtvog drveta i zaliha ugljika po hektaru u istraživanim sastojinama bukve prikazana je u tablici 7. Biomsa istraživanih sastojina zajedno iznad zemlje je 6,06 t haā€“1, a ispod zemlje 17,34 t haā€“1, odnosno ukupno 23,40 t haā€“1. Zaliha vezanog ugljika u ukupno procijenjenoj suhoj biomasi mrtvog drveta iznad zemlje je 3,03 t C haā€“1 a ispod zemlje 8,67 t C haā€“1, odnosno ukupno 11,70 t C haā€“1.Gospodarene visoke sastojine bukve u Srbiji imaju veći volumen, biomasu i zalihu vezanog ugljika u mrtvom drvetu po hektaru u odnosu na intenzivno gospodarene sastojine bukve u Europi. SadaÅ”nje stanje je posljedica dugogodiÅ”njeg provođenja neurednog gospodarenja i česte promjene načina gospodarenja bukovim Å”umama (preborni, grupimični, naplodni i sl.). Na bazi provedenog istraživanja procijenjeno je (p= 0,95, n-1 = 241) da se u visokim gospodarenim bukovim Å”umama na području Srbije (350.000 ha) nalazi 6,73+/ā€“ 0,92 milijuna m3 mrtvog drveta iznad zemlje, čija je suha biomasa 2,12 +/ā€“ 0,29 milijuna tona a uskladiÅ”teni ugljik u ovoj biomasi 1,06 +/ā€“ 0,14 milijun tona. Biomasa mrtvog drveta ispod zemlje je 6,07 +/ā€“ 0,73 milijuna tona, a uskladiÅ”teni ugljika u ovoj biomasi 3,03 +/ā€“ 0,36 milijuna tona. Prema tomu, ukupna procijenjena biomasa mrtvog drveta iznad i ispod zemlje je 8,19 +/ā€“ 0,82 milijuna tona, a uskladiÅ”teni ugljik 4,10 +/ā€“ 0,41 milijuna tona
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