Omorika Digital repository of the Faculty of Forestry, University of Belgrad
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Doubling genome size of energy willow affects woody stem cell wall structure, chemistry, and biogas yield
No full textEffectiveness in woody biomass utilization is highly dependent on its genetics and physiology. We performed morpho-anatomical, chemical, and biomethane productivity characterizations of one-year-old woody stems in three shrub Salix viminalis genotypes: a diploid (Energo) and its two autotetraploid derivatives (PP-E7 and PP-E13). Tetraploidization affected changes in stem morpho-anatomy and corresponding improved chemical features and biomethane productivity, considerably more pronounced in tetraploid PP-E13, while PP-E7 was more similar to diploid Energo. Compared to diploid Energo, in tetraploid PP-E13 morphometric analysis showed increased stem diameter and higher wood fiber radial double wall thickness, while microscopic analysis suggested higher syringyl to guaiacyl (S:G) ratio of the wood fiber cell wall. Presented changes in stem morpho-anatomy of tetraploid PP-E13 compared to diploid Energo correspond to the improved chemical features: the lower Klason lignin content and higher S:G ratio, the higher cellulose and xylan content, and lower cellulose crystallinity (Crl). Presented improved chemical features, along with the increase in ash content, resulted in a 7.3% (10.3 CH4 mL/g VS) increase in biomethane productivity in tetraploid PP-E13, compared to diploid Energo, suggesting tetraploid PP-E13 as an optimal raw material for fermentation technologies. In addition, besides the well-known chemical markers of willow biomass quality, the presented results highlight key stem morpho-anatomical parameters, which can serve as additional markers in energy willow improvement
Soil moisture regime in lowland forests - quantity and availability of water
No full textWater is one of the key ecological factors that has a great impact to development and productivity of lowland species such as Quercus robur. This paper deals with water regime influence to site conditions of these species and how actually changeable soil moisture affects Q. robur. Studied area includes a protective embankment built on the river bank in order to eliminate flooding effect, which means that all needs for water these associations provide from rainfalls and groundwater. Water regime was monitored during two critical years (extremely dry and extremely wet) on four soil types - Planosol, Fluvisol and Gleysol that belong to hydromorphic (three experimental plots) and Chernozem which belongs to automorphic soils (three experimental plots), respectively. It was studied the distribution of rainfalls and groundwater during the growing seasons and how it affects total and available water amount in the soil. The main focus should be given to available water, because it is located in capillary pores and plants can utilize it. Bearing in mind rainfalls makes just 15-20% of the total water amount in the soil it is much more significant to evaluate its proportion in available water. Based on obtained results, we can deduce that much more suitable site conditions for Q. robur are present on hydromorphic soils due to much greater proportion of groundwater
Pre-Remediation Characterization of petroleum Fractions and Ecotoxicity at the Heating Plant Site
No full textPetroleum is a complex mixture of liquid, gaseous, and solid hydrocarbons,typically found in a liquid state under normal conditions. It is lighter andmore viscous than water, and both flammable and combustible with a highheat of combustion. Today, crude oil poses a significant globalenvironmental hazard. Proper characterization of petroleumcontamination before the remediation process is crucial for understandingthe nature of the contaminants, including the specific types ofhydrocarbons, their concentrations, and their distribution within theaffected area. Without this initial characterization, the remediation processmay be inefficient, ineffective, or even counterproductive, potentiallyleading to incomplete cleanup or further environmental damage
The influence of rainfall factors on soil resistance to erosion
No full textFor the purposes of researching the influence of rainfall factors on soil shear strength, i.e. soil erosion resistance, research was conducted on plots measuring 1.0x0.3 m at a slope of 15°, with equally prepared soil. It’s been carried out 12 rainfall simulations with different values of rainfall factors (rainfall intensity and drops diameter). These simulations were carried out with a modified rain simulator with sprayers by Živanović et. al (2021). The analysis of the uniformity of the prepared soil, as well as the examination of the influence of simulated rainfall factors on soil erosion, was carried out by measuring with a pocket vane tester (Eijkelkamp M1.14.10.E). The measurement was carried out at 30 regularly spaced locations on every plot, immediately after the simulation was completed. Also, the measurement was carried out after 24 hours in three places (upper, middle and lower third of the plot). Spatial distribution of measured values was assessed by Christians' coefficient of uniformity CU. The measured shear strength values of the prepared soil range from 2.1 to 6.9 kN/m2. The shear strength values immediately after the simulation range from 0.4 to 5.4 kN/m2, while after 24 hours they range from 2.4 to 8.1 kN/m2. The CU values of the prepared soil range from 68% to 81% (average 75%). Immediately after the simulation, Cu values range from 73% to 83%, while after 24 hours, from 69% to 91%. In general, there is a clear trend of decreasing values measured with the pocket vane tester from the top to the bottom of the plots. Also, the influence of the change in soil moisture on the values of soil shear strength was observed. The change in rainfall factors affects the change in soil resistance to erosion
Productivity of john deere 1470 g harvester in white Willow plantations
No full textResearch on the productivity of the harvester in white willow plantations was conducted
in PE Vojvodinšume, FE Sombor at three locations. The operation of the John Deere
1470G harvester was recorded. The operating conditions varied depending on the
preparation of the terrain. At two locations, the undergrowth was less pronounced, while
at the third location it was much more pronounced. In the area not prepared for
harvesters, the undergrowth was of medium density and the height of the shrub
vegetation was up to 2 metres. The weather conditions during the harvester operation
were very good. The average diameter at breast height of the trees was between 31 and
42 cm, depending on the location. The average logging time for willows was 1.65
min/tree, i.e. the delimbing time was 0.97 min/tree, the time of positioning 0.18 min/tree
and the cutting time was 24 min/tree. The average transition time (from one tree to
another tree) was 0.28 min/tree. The felling and undercutting time increases as the
diameter at breast height of the tree increases, as does the delimbing time. The average
fuel consumption per working hour was between 25.5 l and 34.4 l, depending on the
operating conditions. The downtime amounts to 17 to 20 % of the harvester's operating
time without the preparatory-final time
The Role Of Nwfps In The Development Of Entrepreneurship In Southeastern Serbia
No full textIn the social context, forests have a significant role for many inhabitants, either in the form of livelihood, or income generated from a wide range of wood
and non-wood forest products (NWFPs). In this research, NWFPs were analyzed as a component of rural entrepreneurship in southeastern Serbia. In this
regard, 11 companies dealing with the purchase, processing, and marketing
of mushrooms, forest fruits, and medicinal herbs were surveyed. The period
considered is 2008-2017. The aim of the research was to familiarize with the
elements of business related to the marketing mix (product, price, promotion,
and distribution) in these companies, as well as to assess the possibilities
for their improvement. In this way, it aimed to recognize the potential for
the development of primarily small entrepreneurship in Southeastern Serbia
through the use of NWFPs for commercial purposes
Sistemi agrošumarstva
No full textАгрошумарство представља интеграцију пољопривреде и шумарства
ради остваривања вишеструких користи, укључујући економске, еколошке и друштвене користи. Данас агрошумарство добија све већи значај, јер
је препознато као решење блиско природи (nature-based solution) за бројне глобалне изазове попут климатских промена, губитка биодиверзитета
и одрживог коришћења ресурса. Истовремено, агрошумарство је засновано на традиционалним начинима коришћења земљишног простора, што
може допринети да га различити корисници лакше прихвате
Prisustvo invazivnih vrsta drveća u drvoredima opštine Stari grad u Beogradu
No full textTokom poslednjih decenija problem pojave, kretanja i širenja invazivnih vrsta
biljaka postao je jedan od značajnijih tema kojom se danas bavi naučna i stručna javnost
širom sveta. Neke od negativnih posledica pojave invazivnih vrsta biljaka u nekom
ekosistemu su zauzimanje staništa za autohtone vrste usled njihovog nekontrolisanog
širenja, prenošenja patogena, kao i ekonomskih šteta koje stvaraju zbog primene često
skupih mera njihovog suzbijanj
The Spaces of Ultradistributions Over ℝ+d and the Weyl Calculus of Pseudo-Differential Operators
No full textIn this paper we introduce classes of ultradifferentiable functions and the corresponding ultradistributions on ℝ+d, i.e. Gαβ(ℝ+d) and (Gαβ(ℝ+d))′, α,β gt 0, respectively. We give their characterisation through the Laguerre coefficients estimate. Furthermore, we define the modified fractional power of the partial Hankel-Clifford transform and show that this transformation is a topological isomorphism on Gαα(ℝ+d), α≥1. We also investigate the boundedness of the Weyl pseudo-differential operators with symbols from the previously introduced spaces
New Ophiostoma species associated with Dryocoetes himalayensis and decline of Juglans regia in Czechia
No full textA new ophiostomatoid fungus involved in the decline of walnuts was discovered in Czechia. The fungus was isolated from necrotic wood surrounding the larval galleries of Dryocoetes himalayensis, the alien bark beetle attacking walnut trees. This insect species is rather unique within hardwood-associated bark beetle species for its aggressiveness and ability to attack apparently healthy trees. The isolated fungus, associated with an exotic insect vector is described as a new species, Ophiostoma juglandis sp. nov., based on its unique morphology and phylogenetic position. The pathogenicity tests confirmed the aggressiveness of the species to both Juglans regia and J. nigra plants, manifested by formation of extensive bleeding and necrotic lesions. The symbiotic relationship between O. juglandis and D. himalayensis is expected due to massive presence of the fungal spores on surface of adult beetles in pits forming the elytral striae. In the case of hardwood-associated ophiostomatoid fungal species, phytopathogenicity is very rarely observed. The described species is exceptional in this ability, which corresponds to the aggressive behaviour of its vector. The role of the fungus in walnut tree mortality caused by D. himalayensis is discussed