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A selection of the application of Pinus sylvestris L. from Puszcza Notecka by chemical analysis

Zborowska M., Prądzyński W., Kusiak W., Stachowiak-Wencek A., Roszyk E., Moliński W.

Drewno : prace naukowe, doniesienia, komunikaty

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2018

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vol. 61, nr 202

39--51

EN

Pinus sylvestris L. is the most popular wood material used in building construction and pulp technology. However, it can be also applied for other, more economically beneficial purposes like ethanol, commercial quantities of xylose or glucose as well as substrates for chemical synthesis. The selection of an optimal conversion path of wood should be based on its chemical composition and physical properties. The overall aim of this research was to determine the chemical composition and features of cellulose and lignin structure on a molecular level of Pinus sylvestris L. wood from a primeval forest: Puszcza Notecka was chosen because of its valorisation. The trees from four stands: two from the primeval forest and for comparison two from stands out of the primeval forest were used in the research. The percentage of chemical components of the wood: holocellulose, cellulose, pentosans and lignin as well as components soluble in ethanol and ash were determined. The chemical analysis provided information on the number of wood components. Their variations at a molecular level were investigated by Py-GC/MS, highlighting how the growth place of trees can affect the formation of wood pyrolysis products. The differences between the structures of cellulose and lignin, amidst certain feedstocks were also analysed by FTIR. It was shown that a percentage of the chemical composition of material from the stands in the primeval forest is more homogeneous in comparison to material from other investigated stands. There was a lower content of extractives in wood from the primeval forest which facilitates the gluing and finishing of wood-based materials. A low content of ash in this material gives possibilities to consider using investigated feedstock for energy purposes. The highest content of holocellulose, 77.5%, was found in the wood gained from the primeval forest and this feedstock is the best for obtaining carbohydrate derivatives. Both the low content of lignin and the low content of extractives in wood from Puszcza Notecka allowed them to be applied in the fermentation process. The evaluation of the relative amounts of pyrolysis products deriving from holocellulose and lignin and FTIR analysis highlighted differences between feedstock growing in the compared areas. The results obtained indicated that the trees from Puszcza Notecka are an attractive feedstock for technological branches due to the homogeneous chemical and physical features and they can potentially be used for countless economically-viable applications.

2

Healing rate of logging wounds on broadleaf trees in Hyrcanian forest with some technological implications

Tavankar F., Picchio R., Nikooy M., Lo Monaco A., Venanzi R., Iranparast Bodaghi A.

Drewno : prace naukowe, doniesienia, komunikaty

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2017

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vol. 60, nr 199

65--80

EN

The wound healing rate (WHR) was investigated in 234 wounded trees in Iranian forests and was found to range from 6.4 to 24.0 mm·yr-1. Tree species, slope aspect, elevation, wound age, and wound type had significant effects on the WHR. The mean of the WHR in the Fraxinus excelsior (24 mm·yr-1), Alnus subcordata (18.9 mm·yr-1) and in the Fagus orientalis (17.9 mm·yr-1) were significantly higher than in the Acer insigne (15.7 mm·yr-1), Acer cappadocicum (14.6 mm·yr-1), Carpinus betulus (13.7 mm·yr-1), and Tilia begonifolia (6.4 mm·yr-1). In addition, the mean of the WHR on northern slopes (17.5 mm·yr-1) was significantly higher than on southern slopes. Moreover, the parameters that positively influenced tree growth showed a similar effect on the wound healing rate. The WHRs of 5-, 10- and 15-year-old wounds were 19.3, 16.9 and 10 mm·yr-1, respectively. The WHR increased the higher the wound from ground level. The WHR for horizontal wounds (18.4 mm·yr-1) was significantly higher than for vertical wounds. The highest WHR was estimated in a stand with a canopy closure of 60-80%. The WHR decreased according to increasing wound width. Wounds affect future income, lowering the number of trees that potentially provide a higher quality of saw and veneer logs.

3

Damage caused by harvester head feed rollers to alder, pine and spruce

Karaszewski Z., Łacka A., Mederski P. S., Noskowiak A., Bembenek M.

Drewno : prace naukowe, doniesienia, komunikaty

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2016

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vol. 59, nr 197

77--88

EN

The harvester head causes damage to the bark and wood on the lateral surface of the processed assortment. The severity of the damage may be influenced by the construction of the harvester head and tree species characteristics, such as bark thickness and wood hardness. The study aimed to recognise and compare damage caused to hardwood and softwood. Wood from alder, pine and spruce was harvested using a Valmet 911.4 harvester equipped with a 360.2 head. Logs measuring 2.40 and 2.50 m in length were used in this study. The depth of the damage caused by the feed roller spikes was measured using a digital caliper. Comparison of these defects across the three species revealed that as bark thickness increased so the depth of damage to the timber decreased. Damage to the alder logs in the form of dents and gouged timber fibres was shallow: from 1.7 to 3.7 mm, and significantly less than that to the softwood logs: in the pine from 5.9 to 7.8 mm, and in the spruce from 3.9 to 5.6 mm. Damage to the middle and top logs for each species was similar and depth varied little along the entire length of the processed assortment. Such damage only slightly lowered the quality of the alder wood, which had the thickest bark. Application of the Valmet 911.4 harvester caused less damage to the alder wood than to the softwood (pine and spruce).

4

Value of merchantable timber in Scots pine stands of different densities

Bembenek M., Karaszewski Z., Kondracki K., Łacka A., Mederski P. S., Skorupski M., Strzeliński P., Sułkowski S., Wegiel A.

Drewno : prace naukowe, doniesienia, komunikaty

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2014

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vol. 57, nr 192

133--142

EN

Differences in the intensity of silvicultural treatments, as well as natural tree mort- ality, insect damage and fungal disease can eventually lead to variable stand density even on sites of the same quality. In addition, the bigger the initial stand density, the smaller the crown and trunk volume of single trees. The objective of the research was a detailed analysis of the impact of stand density on the total stand volume and value of merchantable timber. The area studied was in Drawno Forest District, north-west Poland, on sites with sandy soil conditions typical for Scots pine (Pinus sylvestris L.). The total volume of merchantable roundwood was measured on 20 sample plots (each covering an area of 0.5 ha) of which 19 were in 82-year-old stands and one in an 87-year-old stand. The stands were divided into three stand density groups (SDG), where the average number of trees growing per group was as follows: 547 (SDG I), 651 (SDG II) and 765 (SDG III). The volume of a single tree was calculated using diameter (DBH) and height measurement. A quality classification of all 6432 tree stems was carried out in accordance with the Polish Standard. Statistical analysis did not indicate that density influenced the total timber volume of the stands studied, which was recorded as an average of 323 m3∙ha-1. However, statistically significant differences in the value of merchantable timber were observed: the highest value of 100 m3 of merchantable timber was recorded in SDG I (€ 5118.87), 6 and 12% higher than in SDGs II and III (€ 4842.09 and € 4565.80, respectively). The results obtained suggest that in the final phase (the last two age classes), pine stands growing in Polish conditions should be maintained at a lower stand density.

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Strip road impact on selected wood defects of norway spruce (Picea Abies (L.) H. Karst)

Bembenek M., Giefing D. F., Karaszewski Z., Łacka A., Mederski P. S.

Drewno : prace naukowe, doniesienia, komunikaty

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2013

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vol. 56, nr 190

63--76

EN

Creating strip roads in second age class stands is an indispensible operation for carrying out thinning. It is especially important in places where there is an intention to do a first thinning using mechanised thinning operations. Felling trees to create strip roads results in altered conditions for the tree growth of neighbouring trees. In particular, this is due to an increase in exposure to sunlight. This can lead to changes in the growth of trees and consequently changes in the morphology of the trunk and the development of defects. The objective of this paper was to analyse the frequency of the presence of particular defects in the structure and shape of spruce in a five-year period after the creation of a strip road. The research was carried out in an artificially regenerated spruce stand within the spruce’s natural, northern habitat in Poland. A 34-year-old stand underwent a systematic thinning scheme which involved the removal of every eighth tree row. The analysis was carried out on trees growing both adjacent to the strip roads (which had a greater growing area around them and greater access to sunlight) as well as trees from further within the stand. Diameter growth was taken in three places: at breast height, in the middle of the trunk between breast height and the base of the crown, as well as at the base of the crown. The average incremental growth, pith eccentricity taper and ovality were calculated. No statistically significant difference in defects between the trees growing by the strip road and those growing further in the stand was observed. Greater taper on mid-tree logs in comparison to butt logs was observed. Insignificant changes in the morphology of the trunks, supports the validity of cutting strip roads in second age class stands.

PL

Zakładanie szlaków operacyjnych staje się niezbędne przy stosowaniu współczesnych technologii w gospodarce leśnej. Ich obecność to również zwiększony dostęp do światła dla drzew rosnących na ich skraju, co z kolei może wpływać na różnice we wzroście tych drzew w porównaniu z drzewami wewnątrz drzewostanu. Celem pracy była analiza częstości występowania niektórych wad budowy i kształtu mogących wpływać na jakość surowca drzewnego w 5 lat po wykonaniu zabiegu. Drzewostan świerkowy w wieku 34 lat został poddany trzebieży schematycznej poprzez wycięcie co 8. rzędu drzew. Analizie poddano drzewa rosnące przy szlaku PS (z asymetrycznie większymi stoiskami i dostępem do światła) oraz drzewa wewnątrz drzewostanu ( WD 5–10 m od osi szlaku). Badano przyrosty na wysokości pierśnicy, w połowie długości między pierśnicą a podstawą korony i u podstawy korony oraz obliczono przeciętny przyrost, mimośrodowość rdzenia i zbieżystość. Nie zaobserwowano występowania statystycznie istotnych różnic pomiędzy analizowanymi cechami drzew PS i WD, jednakże u drzew rosnących PS zaobserwowano istotnie większą zbieżystość kłód środkowych w porównaniu z odziomkowymi. W krótkim okresie (5 lat) po założeniu szlaków w drzewostanie świerkowym II klasy wieku nie stwierdzono zatem statystycznie istotnych różnic w morfologii pni drzew rosnących przy szlaku i w drzewostanie. Niemniej jednak zaobserwowano: 1) tendencje do zwiększonych przyrostów u drzew PS (szczególnie w połowie pnia) w 5. roku po wykonaniu zabiegu oraz 2) wzrost zbieżystości kłód środkowych wyrobionych z drzew PS. Wyniki te sugerują przeprowadzenie podobnych badań w dłuższym odstępie czasowym (niż 5-letni) od założenia szlaków.

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Drewno na konstrukcję więźby dachowej

Gęsiński Z.

Warstwy, Dachy i Ściany

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2008

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nr 2

36-37